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SynC · Editorial revision

Ductile Iron Process Piping

Revision1
EditedOct 12, 2026
StatusCurrent
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Current revision. This is editorial revision 1, the current text of this standard. Read it on the standard's page.

SynC Standards Team — Specifier (Platform Standards) ✓ OfficialDiscloses employment SynC (SynC Platform Team)
Initial publication

1 Scope

NOTE This standard governs ductile iron pipe, fittings, joints, linings, coatings, couplings, and wall pipes for the process piping of a treatment plant, pump station, or industrial process facility, from the first joint inside the plant fence to the connection at each item of process equipment, tank, channel, or structure. (1.1)
NOTE Process piping is the piping that carries the plant's own fluids between its structures and equipment: raw water, settled and filtered water, finished water, plant utility water, raw sewage, screened and settled sewage, mixed liquor, return and waste activated sludge, primary and digested sludge, scum, plant drain, and treatment chemicals. It is distinguished from the site mains that bring water to the plant or carry sewage to it, which run under the site piping standards, and from building service piping, which runs under the plumbing and mechanical standards. (1.2)
NOTE The boundary with the site piping standards is the plant fence, not the ground. Yard piping that runs buried between plant structures inside the fence is process piping and is governed here; a distribution main that leaves the plant site is governed by Water Distribution PipingSite Water Distribution PipingResolves to the current adopted revision.sync/water-distribution-piping, and a sewer or force main that enters the plant from the collection system is governed by Sanitary Sewer SystemsSanitary Sewer Systems (Site)Resolves to the current adopted revision.sync/sanitary-sewer-systems up to the plant headworks connection shown on the drawings. (1.3)
NOTE This standard governs ductile iron only. Where the piping schedule assigns a run to steel, stainless steel, or a plastic, that run is governed by the sibling standard for that material named in the exclusions below, and the two are connected at the flange, coupling, or adapter shown on the drawings. (1.4)
NOTE The administrative provisions shared by every process standard on the project, including the code basis, submittal procedures, trade coordination, and startup sequence, are stated once in Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process and are not restated here. (1.5)
1.6 The service, nominal size, design working pressure, surge allowance, and pressure class of each line shall be as indicated on the piping schedule.
NOTE The following are outside this scope and are governed by the standards named. (1.7)
  • Steel and stainless steel process piping, including the piping of blowers, digester gas, and high-pressure chemical feed: Steel And Stainless Process PipingSteel and Stainless Steel Process PipingResolves to the current adopted revision.sync/steel-and-stainless-process-piping
  • Thermoplastic, thermoset, and fiberglass process piping, including most chemical feed and solution piping: Plastic Process PipingPlastic Process PipingResolves to the current adopted revision.sync/plastic-process-piping
  • Butterfly valves: Butterfly ValvesButterfly ValvesResolves to the current adopted revision.sync/butterfly-valves; eccentric plug valves: Eccentric Plug ValvesEccentric Plug ValvesResolves to the current adopted revision.sync/eccentric-plug-valves
  • Resilient-seated gate valves: Resilient Seated Gate ValvesResilient-Seated Gate ValvesResolves to the current adopted revision.sync/resilient-seated-gate-valves; process check valves: Process Check ValvesProcess Check ValvesResolves to the current adopted revision.sync/process-check-valves; air release and vacuum valves: Air Release And Vacuum ValvesAir Release and Vacuum ValvesResolves to the current adopted revision.sync/air-release-and-vacuum-valves; actuators, extension stems, and floor stands: Valve And Gate ActuatorsValve and Gate ActuatorsResolves to the current adopted revision.sync/valve-and-gate-actuators; slide gates and stop logs: Slide Gates And Stop LogsSlide Gates and Stop LogsResolves to the current adopted revision.sync/slide-gates-and-stop-logs
  • Process pumps: Horizontal Centrifugal Process PumpsHorizontal Centrifugal Process PumpsResolves to the current adopted revision.sync/horizontal-centrifugal-process-pumps, Vertical Turbine PumpsVertical Turbine PumpsResolves to the current adopted revision.sync/vertical-turbine-pumps, Submersible Solids Handling PumpsSubmersible Solids-Handling PumpsResolves to the current adopted revision.sync/submersible-solids-handling-pumps, and Positive Displacement PumpsPositive Displacement PumpsResolves to the current adopted revision.sync/positive-displacement-pumps; the piping connection to each pump is within this standard
  • Hanger, support, anchor, and structural attachment hardware: Hangers And SupportsHangers and Supports for Mechanical Piping and EquipmentResolves to the current adopted revision.sync/hangers-and-supports
  • Field-applied finish painting of exposed piping: High Performance CoatingsHigh-Performance CoatingsResolves to the current adopted revision.sync/high-performance-coatings
  • Pipe markers, flow arrows, and valve tags: Mechanical IdentificationMechanical IdentificationResolves to the current adopted revision.sync/mechanical-identification
  • Electric heat tracing of exposed outdoor piping: Electric Heat TracingElectric Heat TracingResolves to the current adopted revision.sync/electric-heat-tracing
  • Excavation, construction dewatering, and backfill above the pipe zone: EarthworkEarthworkResolves to the current adopted revision.sync/earthwork
  • Firestop systems at penetrations of rated assemblies: FirestoppingFirestoppingResolves to the current adopted revision.sync/firestopping
  • Water-retaining concrete structures: Water Retaining Concrete StructuresWater-Retaining Concrete StructuresResolves to the current adopted revision.sync/water-retaining-concrete-structures; the wall pipe cast into such a structure is within this standard

2 Referenced Standards

2.1 Materials, fabrication, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2 Where the Contract Documents, the adopted codes, and a referenced standard differ on the same matter, the most stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
Standard Title
AWWA C104/A21.4 Cement-Mortar Lining for Ductile-Iron Pipe and Fittings
AWWA C105/A21.5 Polyethylene Encasement for Ductile-Iron Pipe Systems
AWWA C110/A21.10 Ductile-Iron and Gray-Iron Fittings
AWWA C111/A21.11 Rubber-Gasket Joints for Ductile-Iron Pressure Pipe and Fittings
AWWA C115/A21.15 Flanged Ductile-Iron Pipe With Ductile-Iron or Gray-Iron Threaded Flanges
AWWA C116/A21.16 Protective Fusion-Bonded Coatings for the Interior and Exterior Surfaces of Ductile-Iron and Gray-Iron Fittings
AWWA C150/A21.50 Thickness Design of Ductile-Iron Pipe
AWWA C151/A21.51 Ductile-Iron Pipe, Centrifugally Cast
AWWA C153/A21.53 Ductile-Iron Compact Fittings
AWWA C219 Bolted, Sleeve-Type Couplings for Plain-End Pipe
AWWA C222 Polyurethane Coatings and Linings for the Interior and Exterior of Ductile-Iron Pipe and Fittings
AWWA C600 Installation of Ductile-Iron Mains and Their Appurtenances
AWWA C606 Grooved and Shouldered Joints
AWWA C651 Disinfecting Water Mains
AWWA M41 Ductile-Iron Pipe and Fittings
ASME A13.1 Scheme for the Identification of Piping Systems
ASME B16.1 Gray Iron Pipe Flanges and Flanged Fittings: Classes 25, 125, and 250
ASME B1.20.1 Pipe Threads, General Purpose (Inch)
ASTM A126 Gray Iron Castings for Valves, Flanges, and Pipe Fittings
ASTM A193/A193M Alloy-Steel and Stainless Steel Bolting for High Temperature or High Pressure Service and Other Special Purpose Applications
ASTM A194/A194M Carbon Steel, Alloy Steel, and Stainless Steel Nuts for Bolts for High Pressure or High Temperature Service, or Both
ASTM A307 Carbon Steel Bolts, Studs, and Threaded Rod 60 000 PSI Tensile Strength
ASTM A536 Ductile Iron Castings
ASTM A563 Carbon and Alloy Steel Nuts
ASTM F593 Stainless Steel Bolts, Hex Cap Screws, and Studs
ASTM F594 Stainless Steel Nuts
NSF/ANSI/CAN 61 Drinking Water System Components: Health Effects
NSF/ANSI/CAN 372 Drinking Water System Components: Lead Content
SSPC-SP 10 / NACE No. 2 Near-White Metal Blast Cleaning
GLUMRB Recommended Standards for Water Works and Recommended Standards for Wastewater Facilities (Ten States Standards)
NOTE The AWWA C-series standards for ductile iron are published jointly with the American National Standards Institute under the A21 designations shown, and the two numbers name the same document. The Ten States Standards are cited as the design reference most state reviewers hold a treatment plant to, not as a product standard. (2.3)

3 Submittals

3.1 Action Submittals

3.1.1 The Contractor shall submit the following for the Engineer of Record's review and return before any ductile iron pipe, fitting, or joint component is released for manufacture:
  • Pipe product data for each line service, identifying the nominal size, the pressure class or special thickness class, the joint type, the lining, the exterior coating, and the laying length
  • Flanged pipe product data identifying the thickness class, the flange material and drilling, and the facing
  • Fitting product data identifying the governing AWWA standard, the body material, the joint configuration, the pressure rating, the lining, and the exterior coating
  • Flange gasket and bolting product data for each service and exposure, identifying the gasket elastomer, style, and thickness and the bolt, nut, and washer material and grade
  • Restrained joint and restraint gland product data with the manufacturer's published pressure rating for each size
  • Thrust restraint design for buried piping, showing the restrained length at each fitting, valve, and dead end, the soil parameters and depth of cover used, and the test pressure the design resists
  • Grooved coupling system product data covering couplings, grooved fittings, gaskets, and the groove dimensions for ductile iron pipe
  • Dismantling joint, flanged coupling adapter, and sleeve coupling product data with the restraint method and pressure rating for each location
  • Wall pipe and wall sleeve shop drawings showing the collar type and location, the end connections, the wall thickness, and the embedment
  • Lining and coating product data for each service, with the manufacturer's statement of suitability for that service and the applied thickness
  • Polyethylene encasement product data and the soil corrosivity evaluation on which the encasement determination rests, where encasement is derived from that evaluation
  • Piping layout drawings for each gallery, building, vault, and yard area, showing routing, elevations, joint types and locations, supports, wall penetrations, removal joints, and equipment connections
  • A pressure test plan identifying each test section, its boundaries and isolation, the test pressure, the hold duration, the leakage acceptance criterion, and the sequence that tests buried piping before backfill above the pipe zone and exposed piping before painting or insulation
Action Submittals Requiredcheckbox
☑ Pipe product data by line service
☑ Flanged pipe product data
☑ Fitting product data
☑ Flange gasket and bolting product data
☑ Restrained joint and restraint gland product data
☑ Thrust restraint design for buried piping
☐ Grooved coupling system product data
☑ Dismantling joint, coupling adapter, and sleeve coupling product data
☑ Wall pipe and wall sleeve shop drawings
☑ Lining and coating product data by service
☐ Polyethylene encasement data and soil corrosivity evaluation
☑ Piping layout drawings
☑ Pressure test plan
3.1.2 Pipe, fittings, and wall pipes shall not be released for manufacture until the submittals covering them have been returned by the Engineer of Record.
3.1.3 Each submittal shall be internally consistent across pipe, fittings, flanges, gaskets, and bolting for a given line, and the Contractor shall bear the cost of resubmission caused by inconsistency within its own submittal.
3.1.4 The wall pipe shop drawings shall be returned before the concrete trade closes the formwork in which the wall pipes are to be cast, and the Contractor shall deliver the wall pipes to the site in time to be set in that formwork.
NOTE A wall pipe cast into a water-retaining wall cannot be moved after the concrete is placed. The shop drawing review is the only point at which its elevation, its collar, and its end connection can be checked against the piping on both sides of the wall, which is why it is held ahead of the concrete rather than with the rest of the piping submittal. (3.1.5)

3.2 Closeout Submittals

3.2.1 The Contractor shall submit the following at substantial completion, before the ductile iron process piping is accepted:
  • Manufacturer's certification per AWWA C151 and AWWA C110 or C153 that the pipe and fittings furnished meet the standard, including the factory hydrostatic proof test
  • Signed and dated pressure and leakage test reports for every test section, recording the pressure, hold duration, measured leakage or pressure change, the acceptance criterion, and the pass determination
  • Disinfection and bacteriological test records for every finished-water or potable line, where disinfection is required by this standard
  • Record drawings showing the installed routing, elevations, joint types, restrained lengths, wall pipe locations, removal joints, and the location of every buried fitting and valve referenced to permanent surface features
  • Lining and coating inspection records, including holiday test results where required, and the field touch-up record
  • The thrust restraint design as installed, with any restrained length that differs from the accepted submittal identified
Closeout Submittals Requiredcheckbox
☑ Manufacturer's certifications and factory test records
☑ Signed pressure and leakage test reports
☑ Disinfection and bacteriological test records
☑ Record drawings with buried fitting locations
☑ Lining and coating inspection records
☐ Thrust restraint design as installed
3.2.2 Buried fitting and valve locations on the record drawings shall be measured from permanent surface features after installation, not transcribed from the layout drawings.

4 Quality Assurance

4.1 Manufacturer Qualification and Certification

4.1.1 Ductile iron pipe shall be produced by a manufacturer that has produced centrifugally cast ductile iron pipe to AWWA C151 for not less than five years.
4.1.2 Fittings shall be produced by a manufacturer that has produced ductile iron fittings to AWWA C110 or AWWA C153 for not less than five years.
4.1.3 Each pipe length shall be hydrostatically proof tested at the factory in accordance with AWWA C151 before lining or coating is applied.
4.1.4 The manufacturer shall certify in writing that the pipe, fittings, linings, and coatings furnished comply with the AWWA standards named in the accepted submittals.
4.1.5 Pipe and fittings shall bear the markings required by their governing AWWA standard, including the manufacturer's mark, the year of casting, the nominal size, the pressure class or thickness class, and the material designation.
4.1.6 Domestic manufacture of pipe and fittings shall be required where indicated in the datasheet.
Domestic Manufacture of Pipe and Fittingsradio
○ Required for all pipe and fittings
○ Required where a funding condition applies
○ Not required
NOTE Many treatment plant projects carry a federal or state funding condition that requires domestic iron and steel, and the condition reaches ductile iron pipe and fittings directly. Where it applies, the requirement is settled at bid rather than at submittal; where no funding condition applies, the field is a project preference that narrows the supply of fittings more than the supply of pipe. (4.1.7)

4.2 Installer Qualification

4.2.1 The contractor installing ductile iron process piping shall have completed at least three treatment plant or pump station piping installations of comparable size and joint types within the preceding five years, and shall submit those project references on request.
4.2.2 Where the parties disagree whether a submitted reference project is comparable, the Engineer of Record shall make the initial determination.
4.2.3 Personnel assembling restrained joints, grooved joints, and mechanical joints shall have been trained by the joint manufacturer or shall demonstrate assembly of each joint type to the Engineer of Record before production assembly begins.

4.3 Potable-Water Contact Certification

4.3.1 Pipe, fittings, linings, gaskets, lubricants, and coatings in contact with finished water, potable water, or water that will become potable shall be certified to NSF/ANSI/CAN 61.
4.3.2 Components in contact with potable water shall comply with the lead-content limit of NSF/ANSI/CAN 372.
NOTE The certification covers the lining and the gasket as much as the iron, and a pipe certified with cement mortar lining is not certified with a different lining substituted at the factory. A submittal that names the lining and gasket by product is what lets the certification be checked. (4.3.3)

4.4 Grooved Joint Single-Source Responsibility

4.4.1 Where grooved joints are used, the couplings, grooved fittings, gaskets, and the groove dimensions for a given pipe size shall be the products and published dimensions of a single coupling manufacturer.
4.4.2 Grooved coupling components from different manufacturers shall not be combined in one joint.

5 Service Conditions

5.1 Line Services and Design Pressures

5.1.1 Every component on a line shall be rated for the design working pressure and surge allowance of that line at the operating temperature of the fluid it carries.
NOTE Pressure class, flange rating, restraint design, gasket selection, and the test pressure all take their input from the design working pressure of the line, which is set by the hydraulic design and recorded on the piping schedule. The schedule carries one value per line because a plant runs many pressures at once: a gravity-flow settled water line, a high-service discharge header, and a sludge line to a dewatering press are three different design conditions on the same project. (5.1.2)
NOTE The service classes used by this standard to select linings, gaskets, and coatings are the following, and each line shall be assigned to one of them on the piping schedule: (5.1.3)
  • Water services: raw water, settled and filtered water, finished water, plant utility and non-potable water, backwash supply and waste, and sample water
  • Wastewater services: raw sewage, screened and degritted sewage, primary and secondary effluent, mixed liquor, plant drain, and filtrate or centrate return
  • Sludge and scum services: primary, waste activated, return activated, thickened, and digested sludge, scum, and grease
  • Chemical services: treatment chemical feed and solution lines assigned to ductile iron on the piping schedule
  • Air and gas services: process air and gas lines assigned to ductile iron on the piping schedule
5.1.4 The design operating temperature of each line, where it exceeds 120°F, shall be as indicated on the piping schedule.
NOTE Ductile iron pipe itself is not limited by the temperatures a treatment plant produces, but its linings, gaskets, and polyethylene encasement are. Cement mortar lining and the standard gasket elastomers are rated for ordinary water and wastewater temperatures; a heated sludge line from a digester heat exchanger, or a hot chemical dilution line, is the case the schedule flags so that the lining and gasket rating can be checked against it. (5.1.5)

5.2 Site Conditions

5.2.1 Buried piping shall be installed with the top of the pipe below Frost DepthFrost DepthParameterEach project supplies its own value.frost-depth unless the piping is designed to be drained or heat traced through the winter and is so indicated on the drawings.
5.2.2 The thrust restraint design for buried piping shall use the soil parameters of the geotechnical report and shall account for the saturated condition where the pipe zone lies below Seasonal High Groundwater ElevationSeasonal High Groundwater ElevationParameterEach project supplies its own value.seasonal-high-groundwater-elevation.
5.2.3 Exposed piping, its supports, and its anchorage shall be designed and restrained for Seismic Design CategorySeismic Design CategoryParameterEach project supplies its own value.seismic-design-category in accordance with Adopted Building CodeAdopted Building CodeParameterEach project supplies its own value.adopted-building-code, and the restraint provisions shall be shown on the piping layout drawings.
5.2.4 Exposed piping outdoors, and piping in unheated structures, shall be protected from freezing where Site Ambient Temperature MinimumSite Ambient Temperature MinimumParameterEach project supplies its own value.site-ambient-temperature-minimum is below 32°F, by the drain provisions shown on the drawings, by heat tracing under Electric Heat TracingElectric Heat TracingResolves to the current adopted revision.sync/electric-heat-tracing, or by both as indicated on the process mechanical plans.
NOTE A restrained-joint system is designed against the friction and bearing of the soil along the restrained length, and saturated soil develops less of both. The seasonal high groundwater is the design condition rather than the water level on the day of the test, because the thrust is permanent and the groundwater is seasonal. (5.2.5)

6 Ductile Iron Pipe

6.1 Pipe Standard and Wall Designation

6.1.1 Ductile iron pipe shall conform to AWWA C151, centrifugally cast, with a wall thickness determined in accordance with AWWA C150 for the pressure class or special thickness class indicated on the piping schedule.
6.1.2 The wall designation system for pipe with push-on and mechanical joints shall be as indicated in the datasheet.
Wall Designation for Push-On and Mechanical-Joint Piperadio
● Pressure class per AWWA C150 and C151
○ Special thickness class per AWWA C151
NOTE Pressure class is the designation AWWA C151 has used since the thickness design method of AWWA C150 was adopted, and it names what the engineer actually designs for: the pressure the wall resists with the standard surge and safety allowances. Special thickness class is the older ladder of nominal walls, Class 50 through Class 56, and it persists where an owner's standards were written in those terms or where a wall heavier than the pressure requires is wanted for handling, tapping, or grooving. The two systems overlap, and a submittal that states both for the same pipe is acceptable so long as the heavier wall governs. (6.1.3)
6.1.4 Pipe for any line shall not be furnished in a pressure class lower than the class indicated on the piping schedule for that line, and shall not be lower than Pressure Class 350 for sizes 12 in. and smaller.
NOTE Pressure Class 350 is the lightest wall AWWA C151 lists for 12 in. and smaller, so the clause above is a floor the manufacturer cannot fall below rather than a project selection. Larger sizes are made in Pressure Class 150 through 350, and the schedule selects among them per line. (6.1.5)
6.1.6 Pipe to be cut, tapped, or grooved in the field shall have a wall not thinner than the minimum the manufacturer publishes for that operation at that size.

6.2 Flanged Pipe

6.2.1 Flanged ductile iron pipe shall conform to AWWA C115, with ductile iron threaded flanges, faced after assembly, and with the flange and pipe thread conforming to that standard.
6.2.2 The pipe wall thickness class for flanged pipe shall be not less than the special thickness class indicated in the datasheet.
Thickness Class for Flanged Piperange
53545556
Default: Not less than 53
NOTE AWWA C115 sets special thickness Class 53 as the minimum wall on which a threaded flange is permitted, because the thread is cut into the pipe wall and the remaining wall at the root has to carry the pressure. Class 53 is the wall nearly every plant flanged-pipe specification names; a heavier class is selected where the pipe is also to be field tapped or where the owner's standards call for it. (6.2.3)
6.2.4 Flanges on flanged pipe shall be flat-faced, and no raised-face flange shall be used anywhere in the ductile iron piping.
NOTE A raised-face flange bolted to a flat-faced ductile iron flange bears only on the raised ring, and as the bolts are drawn up it bends the iron flange over the edge of the ring. Ductile iron tolerates this better than gray iron, but the joint is still being loaded in a way neither flange was designed for, and the fix at a mating steel valve or pump is to specify the steel flange flat-faced rather than to accept the mismatch. (6.2.5)
6.2.6 Threaded flanges shall be assembled at the factory, and field threading and flanging of ductile iron pipe shall not be performed unless the Engineer of Record approves it in writing for a specific location.
6.2.7 Flanged pipe shall be furnished in the lengths shown on the piping layout drawings, with the laying length measured face to face of the flanges.
6.2.8 Threaded flanges on flanged pipe shall be of the material indicated in the datasheet, and gray iron flanges, where permitted, shall conform to ASTM A126 Class B and AWWA C115.
Threaded Flange Material on Flanged Piperadio
● Ductile iron only
○ Ductile iron or gray iron

6.3 Pipe Marking and Factory Testing

6.3.1 Each pipe length shall be marked in accordance with AWWA C151 with the manufacturer's mark, the year of casting, the nominal size, the pressure class or thickness class, and the letters DI or the word DUCTILE.
6.3.2 Each flanged pipe length shall additionally bear the thickness class and the AWWA C115 marking.
6.3.3 The factory hydrostatic proof test of AWWA C151 shall be performed on each length, and the manufacturer's certification shall state the test pressure and duration.

7 Fittings

7.1 Fitting Standard and Body

7.1.1 Fittings for flanged piping shall conform to the standard indicated in the datasheet.
Flanged Fitting Standardradio
● Full-body fittings per AWWA C110
○ Compact fittings per AWWA C153
7.1.2 Fittings for push-on and mechanical-joint piping shall conform to the standard indicated in the datasheet.
Push-On and Mechanical-Joint Fitting Standardradio
● Compact fittings per AWWA C153
○ Full-body fittings per AWWA C110
NOTE AWWA C110 fittings are the full-body pattern, available in every joint configuration and in the larger sizes, and they are the fittings nearly every flanged plant installation is built from because the flanged pattern is standard and the body length matches the layout tables engineers draw from. AWWA C153 compact fittings carry the same pressure rating in a shorter, lighter body and have become the ordinary mechanical-joint and push-on fitting of buried work, where the shorter body eases handling in a trench and reduces the restrained length. The flanged compact pattern is made in fewer sizes and configurations than the full-body pattern, which is the condition that keeps full-body as the flanged baseline. (7.1.3)
7.1.4 Fitting body material shall be as indicated in the datasheet.
Fitting Body Materialradio
● Ductile iron per ASTM A536
○ Gray iron per ASTM A126
7.1.5 Fittings shall be rated for a working pressure not less than the design working pressure and surge allowance of the line in which they are installed, and not less than 250 psi for sizes 24 in. and smaller.
7.1.6 Fittings shall bear the markings required by AWWA C110 or AWWA C153, including the manufacturer's mark, the size, the pressure rating, and the material designation.
7.1.7 Fittings shall be lined and coated with the same lining and exterior coating specified for the pipe of the same service and exposure, and the lining shall extend over the full interior surface including the bell and the flange face inside the gasket seat.
7.1.8 Bends in the piping shall be made with fittings, and no ductile iron pipe shall be bent, heated, or mitered.

7.2 Outlets and Taps

7.2.1 Branch connections larger than 2 in. shall be made with tee or cross fittings, and no branch larger than 2 in. shall be made by tapping the pipe or fitting wall.
7.2.2 Outlets 2 in. and smaller, for gauges, sample lines, drains, vents, chemical injection points, and instrument connections, shall be made by the method indicated in the datasheet.
Small Outlets 2 in. and Smallerselect
Tapped bosses cast on fittings per AWWA C110 or C153
Threaded outlets drilled and tapped in the pipe wall
Service saddles with a double stainless steel strap
Flanged outlets on fabricated flanged tees
NOTE A tapped boss on a fitting is the outlet the fitting standard provides for, cast with the wall to take the thread, and it is the cleanest outlet where a fitting is already at the location. A direct tap into the pipe wall is permitted by AWWA C151 only where the wall is thick enough to carry the full thread engagement at that size, which the manufacturer publishes by pressure class, and it is the outlet that gets drilled wherever a gauge is wanted on a straight run. A service saddle carries the thread in its own body and is used where the wall is too thin for a direct tap or where the outlet is added after the pipe is in service. A flanged outlet is a small branch made as a fitting and is the only one of the four that takes a flanged instrument or valve directly. (7.2.3)
7.2.4 Direct taps in the pipe wall shall be made only where the pipe wall provides the full thread engagement AWWA C151 requires for the tap size and pressure class, and shall be made with a tapping machine, not by hand.
7.2.5 Pipe threads for tapped outlets shall conform to ASME B1.20.1.
7.2.6 Live taps on an existing line under pressure shall be made with a tapping sleeve and valve of the size and at the location shown on the process mechanical plans.

8 Joints

8.1 Joint Type by Location

8.1.1 The joint type for exposed piping in galleries, buildings, vaults, and wet wells shall be as indicated in the datasheet.
Joint Type, Exposed Pipingselect
Flanged
Grooved per AWWA C606
Restrained push-on
Mechanical joint with restraint glands
NOTE Flanged joints are self-restraining, take apart at any flange for maintenance, hold the pipe rigidly in line, and are the joint nearly every exposed plant installation is built with; they are also the heaviest and the slowest to assemble, and they transmit every load and misalignment straight into the next flange. Grooved joints assemble in a fraction of the time and admit a small deflection at each flexible coupling, which is what makes them attractive on long exposed runs and at equipment, at the cost of a gasket in the pressure boundary at every joint and a groove cut into the wall. Restrained push-on joints in exposed work bring the economy of the buried joint indoors, with a joint that cannot be taken apart without pulling the pipe. Mechanical joints with restraint glands are the common exposed joint in older plants and in vaults, where the adjustability of the gland helps the fit-up. (8.1.2)
8.1.3 The joint type for buried yard piping shall be as indicated in the datasheet.
Joint Type, Buried Yard Pipingselect
Push-on, with restrained joints where thrust restraint requires
Restrained push-on throughout
Mechanical joint, with restraint glands where thrust restraint requires
Restrained mechanical joint throughout
Flanged
NOTE A push-on joint is the fastest and least costly buried joint and seals by a gasket compressed in the bell, so it carries no thrust; the restrained lengths at fittings carry the thrust and the plain push-on joints run between them. Restraining every buried joint costs more per joint and removes the thrust restraint calculation from the field entirely, which is what a plant with congested yard piping and many fittings often chooses. Mechanical joints bolt up with a gland and admit field deflection and disassembly, and they are the joint a valve or fitting in a vault is usually furnished with. Flanged buried piping is uncommon because the bolts are buried and the joint cannot deflect, and it is used where a short buried run connects two flanged vault assemblies. (8.1.4)
8.1.5 Joints within a structure, vault, or wet well and joints within 5 ft of a wall pipe shall be the exposed joint type regardless of whether the adjacent piping is buried.
8.1.6 Joints of different types shall be combined only at a fitting, flange, or adapter made for both, and the transition component shall be rated for the design working pressure of the line.

8.2 Flanged Joints

8.2.1 Flanges on pipe, fittings, and flanged accessories shall be drilled to the ASME B16.1 class indicated in the datasheet.
Flange Drillingradio
● Class 125
○ Class 250
NOTE AWWA C110 and C115 flanges are Class 125 drilled and rated for 250 psi working pressure with the gasket and bolting of those standards, which covers the design pressure of nearly every treatment plant line. Class 250 drilling is selected for a high-service or high-lift discharge whose design pressure and surge exceed the Class 125 rating, and it has to be carried through every mating valve, pump flange, and accessory on that line. (8.2.2)
8.2.3 Flanges shall be flat-faced with the gasket seat machined after the flange is threaded onto the pipe.
8.2.4 Flange gaskets shall be full-face or ring style as indicated in the datasheet.
Flange Gasket Styleradio
● Full-face
○ Ring
8.2.5 Flange gaskets shall be 1/8 in. thick unless the gasket manufacturer publishes a different thickness for the gasket material and flange class.
8.2.6 The flange gasket material for water services shall be as indicated in the datasheet.
Flange Gasket Material, Water Servicesselect
Styrene-butadiene rubber (SBR)
Ethylene propylene diene monomer (EPDM)
Nitrile
Neoprene
8.2.7 The flange gasket material for wastewater, sludge, and scum services shall be as indicated in the datasheet.
Flange Gasket Material, Wastewater, Sludge, and Scum Servicesselect
Nitrile
Ethylene propylene diene monomer (EPDM)
Styrene-butadiene rubber (SBR)
Neoprene
8.2.8 The flange gasket material for chemical services shall be as indicated in the datasheet.
Flange Gasket Material, Chemical Servicesselect
Ethylene propylene diene monomer (EPDM)
Fluoroelastomer
Polytetrafluoroethylene-bonded elastomer
Nitrile
Derived — the chemical and concentration assigned to the line on the piping schedule, per the gasket manufacturer's published chemical compatibility (by default)
NOTE SBR is the gasket AWWA C111 and C115 are written around, holds up in cold and ambient water for decades, and is the lowest-cost elastomer; it swells in oil and grease and is attacked by ozone and by sustained chloramine exposure. EPDM resists chloramine, ozone, and heat better than SBR and is the gasket many potable-water specifications have moved to for that reason, and it fails quickly in oil and grease. Nitrile resists oil, grease, and the hydrocarbons that scum and sludge carry, which is why it is the common sludge and scum gasket, and it has a lower temperature limit and less ozone resistance than EPDM. Neoprene sits between the others on oil resistance and on cost. For a chemical line the elastomer follows the chemical alone: fluoroelastomer and bonded PTFE cover the oxidizers and acids that destroy the hydrocarbon rubbers. (8.2.9)
8.2.10 Flange gaskets in contact with potable water shall be certified to NSF/ANSI/CAN 61.
8.2.11 Flange bolting for exposed piping in dry, indoor locations shall be of the material indicated in the datasheet.
Flange Bolt Material, Exposed Dry Locationsselect
Zinc-plated carbon steel per ASTM A307 Grade B with ASTM A563 nuts
Hot-dip galvanized carbon steel per ASTM A307 Grade B with ASTM A563 nuts
Type 304 stainless steel per ASTM F593 with ASTM F594 nuts
Type 316 stainless steel per ASTM F593 with ASTM F594 nuts
8.2.12 Flange bolting for buried, submerged, wet well, and outdoor locations, and for any location subject to washdown or chemical splash, shall be of the material indicated in the datasheet.
Flange Bolt Material, Buried, Submerged, and Wet or Corrosive Locationsselect
Type 316 stainless steel per ASTM F593 with ASTM F594 nuts
Type 304 stainless steel per ASTM F593 with ASTM F594 nuts
Stainless steel per ASTM A193 Grade B8M with ASTM A194 Grade 8M nuts
Hot-dip galvanized carbon steel per ASTM A307 Grade B with ASTM A563 nuts
8.2.14 Stainless steel bolts shall be assembled with an anti-seize compound on the threads, and nuts shall be of a different hardness grade from the bolt or shall be of a galling-resistant alloy where the bolt manufacturer so requires.
8.2.15 Flange bolts shall be of a length that leaves not less than one full thread and not more than one-half in. projecting beyond the nut after tightening.
8.2.16 Flange bolts shall be tightened in a crossing pattern in at least three passes to the torque published by the gasket manufacturer for the gasket material and flange class.
8.2.17 Flanges shall be aligned and brought parallel before any bolt is tightened, and bolts shall not be used to pull misaligned flanges together.
8.2.18 Where a ductile iron flange mates to a steel flange on a valve, pump, or accessory, the steel flange shall be flat-faced, or the Contractor shall furnish a flat-faced flange adapter between them.

8.3 Push-On and Mechanical Joints

8.3.1 Push-on and mechanical joints shall conform to AWWA C111, with gaskets of the elastomer indicated for the service of the line in the Flanged Joints article of this standard.
8.3.2 Mechanical-joint bolts and nuts shall be of the material indicated in the datasheet.
Mechanical-Joint Bolt Materialselect
High-strength low-alloy steel per AWWA C111
Type 304 stainless steel per ASTM F593 with ASTM F594 nuts
Type 316 stainless steel per ASTM F593 with ASTM F594 nuts
NOTE The low-alloy T-bolt of AWWA C111 is the bolt the mechanical joint was designed around, forms a protective oxide in soil, and is what nearly every buried mechanical joint is assembled with, especially under polyethylene encasement. Stainless steel is selected where the joint is exposed in a wet well or vault, where it is submerged, or where the soil is corrosive enough that the owner wants the bolt removed from the corrosion cell, and it is assembled with anti-seize to prevent galling. (8.3.3)
8.3.4 Push-on joints shall be assembled with the gasket seated in the bell groove, the spigot lubricated with the lubricant furnished by the pipe manufacturer, and the spigot inserted to the depth mark.
8.3.5 Mechanical-joint bolts shall be tightened alternately around the joint to the torque range of AWWA C111 for the bolt size, and the gland shall bear evenly on the gasket around its full circumference.
8.3.6 Joint deflection at any push-on or mechanical joint shall not exceed the deflection published by the pipe manufacturer for the joint type and size, and where a change of direction exceeds the available deflection, a fitting shall be used.
8.3.7 Lubricant for push-on joints in potable service shall be certified to NSF/ANSI/CAN 61, and no petroleum product shall be used as a joint lubricant.

8.4 Grooved Joints

8.4.1 Grooved joints shall conform to AWWA C606, with grooves cut to the radius-cut groove dimensions that standard specifies for ductile iron pipe, and with couplings and grooved fittings of ductile iron per ASTM A536.
8.4.2 Grooves in ductile iron pipe shall be cut, not rolled, and the pipe wall shall be of a thickness class for which the coupling manufacturer publishes a cut-groove pressure rating at that size.
NOTE A roll groove displaces wall and depends on a ductile, thin-walled pipe to form around the roll, which is why it belongs to steel pipe; ductile iron is cut-grooved, and the groove depth comes out of the wall, which is why the wall class matters and why the coupling manufacturer rates the joint by wall as well as by size. (8.4.3)
8.4.4 The grooved coupling gasket compound shall be as indicated in the datasheet.
Grooved Coupling Gasket Compoundselect
Ethylene propylene diene monomer (EPDM)
Nitrile
Fluoroelastomer
Not applicable, no grooved joints
NOTE The gasket is the pressure boundary of a grooved joint, so its compound follows the line service exactly as a flange gasket does: EPDM for water, nitrile for wastewater, sludge, and scum, and fluoroelastomer where a chemical attacks both. A grooved gasket is compressed by the housing rather than by bolts through a flange, so its temperature rating is reached sooner than a flange gasket of the same compound. (8.4.5)
8.4.6 The grooved coupling type on straight runs shall be as indicated in the datasheet.
Grooved Coupling Type on Straight Runsradio
● Rigid
○ Flexible
NOTE A rigid coupling grips the groove and holds the pipe in line as a flange would, so a run of rigid couplings is supported like flanged pipe. A flexible coupling permits a small angular and axial movement at every joint, which is useful at a defined location to absorb vibration, differential settlement between structures, or thermal movement, and which turns a long run into a chain of hinges if used throughout. Where flexible couplings are used, they are placed at the locations the layout drawings designate and the pipe on each side is supported and guided as the movement requires. (8.4.7)
8.4.8 Unless the datasheet selects flexible couplings on straight runs, flexible grooved couplings shall be used only at the locations designated on the piping layout drawings for movement or vibration.
8.4.9 Grooved couplings used where thrust restraint is required shall be of a type rated by the manufacturer to carry the full thrust at the test pressure.

8.5 Thrust Restraint of Buried Piping

8.5.1 Every fitting, valve, reducer, dead end, and change in direction in buried piping shall be restrained against the thrust developed at the hydrostatic test pressure by the method indicated in the datasheet.
Buried Thrust Restraint Methodselect
Restrained joints for the calculated restrained length each side of the fitting
Mechanical-joint wedge-action restraint glands for the calculated restrained length
Concrete thrust blocks bearing on undisturbed soil
Restrained joints, with concrete thrust blocks at selected fittings
NOTE Restrained joints carry the thrust into the pipe string, where the friction and bearing of the soil along a calculated length resists it; the pipe can then be excavated and worked on without disturbing a block, which is why restrained joints are the common choice inside a plant where yard piping is dense and every fitting is near another line. Wedge-action restraint glands do the same on mechanical joints and are the restraint most buried valves and vault connections are made with. Concrete thrust blocks are the lowest-cost restraint where the soil bears well and the fitting has room behind it, and they are the choice that puts a block of concrete against the next trade's excavation and against the adjacent pipe; where blocks are used in a plant they are drawn individually rather than left to a table. (8.5.2)
8.5.3 The restrained length at each fitting shall be calculated for the test pressure, the pipe size, the depth of cover, and the soil type, using the method of AWWA M41, and the calculation shall be submitted as the thrust restraint design.
8.5.4 Where polyethylene encasement is applied to restrained piping, the restrained length shall be calculated with the reduced friction coefficient for encased pipe that AWWA M41 states.
NOTE Polyethylene film between the pipe and the soil is a slip plane, and a restrained length calculated for bare iron is too short on an encased pipe. The encasement decision and the restraint design are made by different people on most projects, which is why the dependency is written here. (8.5.5)
8.5.6 Thrust blocks shall bear against undisturbed soil, shall be sized for the bearing capacity of the soil at that location as stated in the geotechnical report, and shall not cover any joint, bolt, or gland.
8.5.7 Restrained joints and restraint glands shall be rated by their manufacturer for a working pressure not less than the design working pressure of the line and for the full thrust at the test pressure.

8.6 Restraint of Exposed Piping

8.6.1 Every exposed joint that is not self-restraining shall be restrained against the thrust developed at the hydrostatic test pressure, by a restrained joint, a harnessed coupling, or an anchor shown on the piping layout drawings.
NOTE A flanged joint is self-restraining and a rigid grooved coupling rated for the thrust is self-restraining; a push-on joint, a mechanical joint without a restraint gland, a flexible grooved coupling, and a plain sleeve coupling are not, and each of them separates under pressure if nothing else holds the pipe. Exposed piping has no soil to lean on, so every one of those joints needs a restraint that can be seen and checked, and the equipment nozzle at the end of the run is not that restraint. (8.6.2)
8.6.3 Thrust at an exposed fitting shall not be carried by a pump, valve, or equipment nozzle, and the anchorage that carries it shall be shown on the piping layout drawings.

9 Couplings, Dismantling Joints, and Flexible Connectors

9.1 Removal Joints at Equipment and Valves

9.1.1 A removal joint shall be provided in the piping at each pump, each flanged valve 4 in. and larger, each flow meter, and each other item of equipment, located so that the item can be removed without cutting pipe or springing the adjacent piping, and of the type indicated in the datasheet.
Removal Joint at Equipment and Valvesselect
Dismantling joint
Flanged coupling adapter
Sleeve-type coupling per AWWA C219 with harness
Flexible grooved coupling
NOTE A dismantling joint is a flanged coupling adapter and a flanged spool built as one restrained unit, with tie rods that take the thrust and an adjustment range that lets the joint be collapsed to free the equipment; it is the removal joint nearly every plant now specifies at pumps and large valves because it is restrained as furnished and needs no separate harness. A flanged coupling adapter does the same on one side only and takes an external harness or tie rods to restrain it. A sleeve-type coupling joins two plain ends, admits some misalignment, and is restrained by tie rods or harness lugs across it. A flexible grooved coupling is the removal joint of a grooved system, and it is restrained by its own grip in the groove when rated for the thrust. (9.1.2)
9.1.3 Dismantling joints, flanged coupling adapters, and sleeve-type couplings shall be rated for a working pressure not less than the design working pressure of the line and shall be restrained against the full thrust at the test pressure.
9.1.4 Flanged coupling adapters and sleeve-type couplings shall conform to AWWA C219, with ductile iron or carbon steel bodies, and shall be lined and coated with the same system specified for the adjoining pipe.
9.1.5 Sleeve-type couplings and flanged coupling adapters that are not of a self-restraining type shall be restrained with tie rods or a harness across the coupling, of the same bolt material specified for flanges in that location, sized for the thrust at the test pressure.
NOTE An unrestrained sleeve coupling holds the pipe by the friction of its gaskets, and that friction is small compared with the thrust on a closed valve at test pressure. The coupling was bought to let the pipe be taken apart, and it will do exactly that under pressure unless something else holds the ends together. (9.1.6)
9.1.7 Dismantling joints and couplings shall be located so that their bolts and tie rods are accessible for tightening and removal after the adjacent piping, supports, and equipment are installed.

9.2 Flexible Connectors at Equipment

9.2.1 Where the drawings designate a flexible connector at an item of equipment to isolate vibration or accommodate movement, the connector shall be of the type indicated in the datasheet.
Flexible Connector Type at Equipmentselect
Elastomeric spherical expansion joint with control rods
Sleeve-type coupling with harness
Flexible grooved coupling
Not applicable, no flexible connectors designated
NOTE An elastomeric expansion joint absorbs vibration and misalignment in three axes and needs control rods to keep it from extending under pressure; it is the connector at a vibrating pump where the piping is rigid flanged iron. A harnessed sleeve coupling admits a small angular offset and no vibration isolation, and it is the connector where the concern is settlement between a structure and the yard piping rather than vibration. A flexible grooved coupling gives a small movement at low cost and is the connector of a grooved system. (9.2.2)
9.2.3 Flexible connectors shall be rated for the design working pressure and the fluid of the line, and elastomeric connectors shall be of an elastomer selected for the service in the same way as the flange gasket for that service.
9.2.4 Flexible connectors shall not be used as the thrust restraint for the piping, and the piping on each side shall be anchored or restrained independently of the connector.

10 Wall Pipes and Wall Penetrations

10.1 Penetrations Through Water-Retaining Walls

10.1.1 Each pipe passing through a water-retaining wall or slab shall pass through a wall pipe or a wall sleeve of the type indicated in the datasheet, cast into the concrete as the wall is placed.
Penetration Through Water-Retaining Wallsselect
Ductile iron wall pipe with a waterstop collar
Wall sleeve with a waterstop collar and a modular mechanical seal
Wall sleeve with a modular mechanical seal, no collar
10.1.3 Wall pipes shall be ductile iron conforming to AWWA C151 or AWWA C115 for the ends furnished, with a collar integrally cast or attached by the manufacturer's qualified procedure, of a thickness class not less than the flanged pipe class, and with the end connections shown on the wall penetration details.
10.1.4 Collars shall be located at the center of the wall thickness unless the wall penetration details show otherwise, and no collar shall be within 2 in. of either face of the wall.
10.1.5 Wall pipes shall be lined and coated inside and out with the lining and coating specified for the service and exposure on each side of the wall, with the portion embedded in concrete left uncoated or coated as the wall penetration details require.
10.1.6 A tapped boss or a flange shall not be located within the embedded length of a wall pipe.
10.1.7 Wall pipes shall be set in the formwork at the elevation and alignment shown, braced so that concrete placement does not move them, and their open ends shall be closed with a cover until the piping is connected.
10.1.8 Where a wall pipe is set in an existing wall by core drilling, the annular space shall be filled with a non-shrink grout and the collar requirement shall be met by a wall sleeve with a modular mechanical seal and a hydrophilic waterstop around the sleeve, as shown on the wall penetration details.

10.2 Penetrations Through Dry Walls and Floors

10.2.1 Pipe passing through a building wall, floor, or partition that does not retain water shall pass through a sleeve with an annular clearance not less than 1 in. around the pipe, and the annular space shall be sealed at each face.
10.2.2 Sleeves through below-grade building walls and through floors subject to wetting shall be steel or ductile iron pipe, and the annular space shall be closed with a modular mechanical seal rated for the hydrostatic head at the penetration.
10.2.3 Penetrations of fire-resistance-rated assemblies shall be firestopped under FirestoppingFirestoppingResolves to the current adopted revision.sync/firestopping with a system listed for the assembly, the penetrant, and the annular dimension.
10.2.4 Pipe shall not bear on a sleeve, and the pipe shall be supported independently on each side of the penetration.

11 Linings by Service

11.1 Lining Selection

11.1.1 The interior lining of pipe, fittings, wall pipes, and couplings shall be selected per the service class assigned to the line on the piping schedule, as indicated in the datasheets of this article, and shall be applied at the factory.
11.1.2 The interior lining for water services shall be as indicated in the datasheet.
Interior Lining, Water Servicesselect
Cement mortar per AWWA C104
Ceramic-filled amine-cured novolac epoxy
Fusion-bonded epoxy per AWWA C116
Polyurethane per AWWA C222
Unlined
11.1.3 The interior lining for wastewater services shall be as indicated in the datasheet.
Interior Lining, Wastewater Servicesselect
Ceramic-filled amine-cured novolac epoxy
Cement mortar per AWWA C104
Polyurethane per AWWA C222
Fusion-bonded epoxy per AWWA C116
Glass lining
11.1.4 The interior lining for sludge and scum services shall be as indicated in the datasheet.
Interior Lining, Sludge and Scum Servicesselect
Ceramic-filled amine-cured novolac epoxy
Glass lining
Polyurethane per AWWA C222
Cement mortar per AWWA C104
11.1.5 The interior lining for chemical services shall be as indicated in the datasheet.
Interior Lining, Chemical Servicesselect
Ceramic-filled amine-cured novolac epoxy
Polyurethane per AWWA C222
Fusion-bonded epoxy per AWWA C116
Glass lining
Derived — the chemical and concentration assigned to the line on the piping schedule, per the lining manufacturer's published chemical resistance (by default)
11.1.6 The interior lining for air and gas services shall be as indicated in the datasheet.
Interior Lining, Air and Gas Servicesselect
Unlined
Cement mortar per AWWA C104
Fusion-bonded epoxy per AWWA C116
NOTE Cement mortar lining is the lining AWWA C104 provides and the one ductile iron pipe is shipped with unless another is ordered; it protects the iron, keeps the carrying capacity of a water line for the life of the pipe, and costs the least, and it is attacked by soft or aggressive water, by the sulfuric acid that hydrogen sulfide forms above the liquid in a partly full sewage line, and by the acids and solvents of chemical service. Ceramic-filled novolac epoxy is a thick, hard, abrasion- and acid-resistant lining applied to a blasted substrate, and it has become the usual sludge, scum, and raw sewage lining because it holds up where mortar is eaten and it survives the grit that sludge carries; it is applied to pipe only up to the sizes and lengths the applicator can blast and coat, and its price is several times that of mortar. Fusion-bonded epoxy is the AWWA C116 lining of fittings and is a thinner film than the ceramic epoxy, suited to water and to wastewater where abrasion is not the concern. Polyurethane under AWWA C222 is a thick, fast-curing elastomeric lining with good abrasion and chemical resistance, applied to pipe and fittings alike. Glass lining is a fused vitreous enamel, the smoothest and most grease-resistant surface available, and the lining for digested sludge and scum where grease accumulation would otherwise choke the line; it is made in a limited size range, its price is the highest, and it is damaged by impact and by field cutting. Unlined pipe is selected for process air, where there is no water to protect the iron from and a lining would add nothing. (11.1.7)
NOTE Lining selection is tied to the service and not to the plant, because one plant carries every service: a filter plant's finished water, its spent backwash, and its sludge are three linings on three lines, and a wastewater plant's raw sewage, its digested sludge, and its ferric chloride feed are three more. A single plant-wide lining is either overbuilt for the water or underbuilt for the sludge. (11.1.8)
11.1.9 Where a line carries water that will become potable, the lining shall be certified to NSF/ANSI/CAN 61 for that use.
11.1.10 Cement mortar lining for lines in water service shall be of the thickness indicated in the datasheet.
Cement Mortar Lining Thicknessradio
● Standard thickness per AWWA C104
○ Double thickness per AWWA C104
11.1.11 Cement mortar lining shall be seal-coated in accordance with AWWA C104 where the lining is in a potable or finished-water line, unless the datasheet or the water purveyor directs otherwise.

11.2 Lining Application and Field Protection

11.2.1 Linings other than cement mortar shall be applied at the factory to a substrate blast-cleaned to SSPC-SP 10 or to the cleanliness the lining manufacturer requires, to the dry film thickness the manufacturer publishes for the service, and shall be holiday tested after cure.
11.2.2 Ceramic-filled epoxy, polyurethane, and fusion-bonded epoxy linings shall be applied to a nominal thickness not less than the value indicated in the datasheet, measured as dry film thickness.
Dry Film Thickness of Applied Liningsrange
mils
81216202530405060
Default: Not less than 40 mils
NOTE Forty mils is the nominal thickness at which the ceramic-filled epoxy is applied and qualified by its manufacturers for sludge and sewage, and the thickness nearly every specification that names that lining calls for. The thinner setpoints belong to fusion-bonded epoxy, which is a thin-film lining by design, and to polyurethane at its lower range; the thicker setpoints are selected for a grit-laden or highly abrasive line where the lining is expected to wear. (11.2.3)
11.2.4 Cut ends, field-cut pipe, and damaged lining shall be repaired in the field with the repair material the lining manufacturer furnishes for that purpose, applied to the manufacturer's written procedure, before the joint is made.
11.2.5 Glass-lined pipe shall not be cut in the field, and the Contractor shall order glass-lined pipe in the exact lengths the piping layout drawings require.
11.2.6 The Contractor shall bear the cost of replacing lined pipe or fittings whose lining is damaged beyond the manufacturer's published repair limits.

12 Exterior Coatings and Corrosion Protection

12.1 Exposed Piping

12.1.1 The exterior surface of exposed pipe, fittings, and accessories in galleries, buildings, vaults, and outdoor locations above grade shall be prepared and coated at the factory as indicated in the datasheet.
Exterior Coating, Exposed Pipingselect
Shop-applied primer compatible with the field finish system, no asphaltic coating
Asphaltic seal coat per AWWA C151, for field preparation and painting
Shop-applied full coating system, field touch-up only
Bare, blast-cleaned, for field priming and painting
12.1.3 The finish painting of exposed ductile iron piping, including the surface preparation, the coating system, and the color, shall be in accordance with High Performance CoatingsHigh-Performance CoatingsResolves to the current adopted revision.sync/high-performance-coatings.
12.1.4 Shop primers shall be of a type the manufacturer of the field finish system states is compatible with that system, and the Contractor shall submit the compatibility statement with the coating product data.
12.1.5 Exposed flanges, bolts, couplings, and wall pipe faces shall be coated with the same system as the adjoining pipe after the joint is assembled and tested.

12.2 Buried Piping

12.2.1 The exterior coating of buried pipe and fittings shall be as indicated in the datasheet.
Exterior Coating, Buried Pipingselect
Asphaltic seal coat per AWWA C151
Polyurethane per AWWA C222
Fusion-bonded epoxy per AWWA C116
Zinc coating with asphaltic topcoat
NOTE The asphaltic seal coat is the exterior coating AWWA C151 applies to all ductile iron pipe, and it is the buried coating of nearly every installation because the corrosion protection of buried ductile iron is provided by polyethylene encasement where the soil requires it rather than by the coating. A bonded coating, polyurethane or fusion-bonded epoxy, is selected where the owner's corrosion program calls for a coated pipe, where the pipe will be cathodically protected and a low-current-demand surface is wanted, or where the pipe is to be installed by a trenchless method that would strip encasement. A zinc coating under the asphaltic topcoat gives sacrificial protection at coating holidays and is a growing choice in corrosive soils as an alternative to or a companion of encasement. (12.2.2)
12.2.3 Polyethylene encasement of buried piping shall be provided as indicated in the datasheet, in accordance with AWWA C105.
Polyethylene Encasement of Buried Pipingradio
○ Required for all buried piping
○ Required where the soil evaluation indicates corrosive soil
○ Not required
Derived — the soil resistivity and corrosivity evaluation of the geotechnical report, scored per AWWA C105 Appendix A (by default)
NOTE AWWA C105 carries in its Appendix A a ten-point soil evaluation that scores resistivity, pH, redox potential, sulfides, and moisture, and the encasement determination follows from that score; where the geotechnical report supplies the inputs, the determination is objective, which is why the field starts derived. Encasing all buried piping regardless of the score is the position of owners who have had a failure or who would rather not depend on a soil survey of a site that will be regraded, and it costs the project the film and the labor on every length. (12.2.4)
12.2.5 Polyethylene encasement shall be of the film and thickness AWWA C105 specifies, installed by one of the methods that standard describes, with all overlaps taped and all joints, fittings, valves, and appurtenances wrapped.
12.2.6 Encasement damaged during installation or backfill shall be repaired in accordance with AWWA C105 before the trench is backfilled above the pipe zone.
12.2.7 Buried bolts, glands, and restraint devices shall be coated with a bituminous or petrolatum coating before encasement or backfill, and shall be wrapped within the encasement where encasement is provided.
12.2.8 Where the drawings show cathodic protection, bonding, or test stations for buried piping, the joint bonding and test leads shall be installed as shown on the corrosion protection details and as Cathodic ProtectionCathodic ProtectionResolves to the current adopted revision.sync/cathodic-protection requires.

12.3 Submerged Piping

12.3.1 The exterior surface of pipe, fittings, and accessories submerged in a tank, channel, wet well, or basin, and of piping in the vapor space above the liquid, shall be protected as indicated in the datasheet.
Exterior Protection, Submerged Pipingselect
Same lining material as the interior, shop-applied inside and out
Immersion-grade coating system under the high-performance coatings standard, field-applied
Fusion-bonded epoxy per AWWA C116, shop-applied
NOTE A submerged pipe sees the tank contents on its outside exactly as the interior sees the line contents, and the vapor space above a wastewater liquid is worse than the liquid; the simplest protection is to line the pipe inside and out at the factory with the lining already selected for the service. A field-applied immersion system is used where the pipe arrives with the standard asphaltic coating or where the submerged assembly is fabricated on site, and it depends on field blasting and on a cure before the tank is filled. Fusion-bonded epoxy is the shop-applied option for fittings and short pieces. (12.3.2)
12.3.3 Submerged bolts, nuts, and washers shall be stainless steel of the grade selected for submerged locations in the Flanged Joints article of this standard.

12.4 Dissimilar-Metal Isolation

12.4.1 Where ductile iron piping connects to stainless steel, copper, brass, or bronze piping or to the stainless steel nozzle of an item of equipment, the connection shall be made through an insulating flange kit comprising an insulating gasket, insulating sleeves on every bolt, and insulating washers under every nut and bolt head on one side of the joint, unless the drawings designate the connection as uninsulated.
12.4.2 Insulating flange kits shall be rated for the design working pressure of the line and for the fluid in it, and the insulating gasket shall be of a material selected for the service in the same way as the flange gasket for that service.
12.4.3 Buried piping that is electrically continuous with exposed piping through a wall pipe shall be isolated from the exposed piping with an insulating flange kit where the corrosion protection details so require, as shown on the corrosion protection details.
NOTE Ductile iron is the anode in every couple it forms with stainless steel, copper, and bronze, and in a conductive fluid the couple consumes the iron at the joint. The insulating kit is cheap and invisible after installation, and a kit that omits the bolt sleeves is electrically continuous through every bolt and isolates nothing, which is why the sleeve count is written into the requirement. (12.4.4)

13 Delivery, Storage, and Handling

13.1 Pipe, fittings, and accessories shall be delivered with the manufacturer's markings legible and with the lining, coating, and bell and spigot surfaces undamaged.
13.2 Pipe shall be handled with wide fabric slings or padded forks, and no hook, chain, or cable shall be passed through the bore or over a flange face, lining, or spigot end.
13.3 Pipe shall be stored off the ground on timbers or cradles, blocked against rolling, with the bells and spigots clear of the ground and with no pipe stacked higher than the manufacturer's published stacking height for that size.
13.4 Gaskets, lubricants, and polyethylene encasement shall be stored out of direct sunlight and within the temperature range their manufacturer publishes, and no gasket shall be used after the date its manufacturer marks.
13.5 Lined pipe and fittings shall be stored with the ends covered, and ceramic epoxy, polyurethane, and glass linings shall be protected from impact, from direct sunlight where the lining manufacturer requires it, and from freezing where the manufacturer so requires.
13.6 Open ends of installed piping shall be closed with a cap, plug, or cover at the end of each work period and whenever work on that run is not in progress.
NOTE An open pipe in a treatment plant under construction fills with the same grit, timber, and tools that every other open pipe does, and the plant's first flush delivers it to the pump impeller or the chemical injector downstream. The cap costs less than the first strainer cleaning. (13.7)
13.8 The Contractor shall bear the cost of repairing or replacing pipe, fittings, linings, coatings, and gaskets damaged in delivery, storage, or handling.

14 Installation of Exposed Piping

14.1 Routing, Alignment, and Supports

14.1.1 Exposed piping shall be installed along the routing and at the elevations shown on the process mechanical plans and sections and on the accepted piping layout drawings.
14.1.2 Piping shall be installed plumb, level, and parallel to the structure, with flanges aligned and parallel before bolting, and no pipe shall be sprung, forced, or pulled into position to meet a flange, a support, or an equipment nozzle.
14.1.3 Hanger, support, anchor, and structural attachment hardware shall be furnished and installed in accordance with Hangers And SupportsHangers and Supports for Mechanical Piping and EquipmentResolves to the current adopted revision.sync/hangers-and-supports.
14.1.4 Exposed horizontal piping shall be supported at intervals not greater than the value indicated in the datasheet, and in any case not greater than one pipe length, with a support within 2 ft of each change in direction and each non-rigid joint.
Support Spacing, Exposed Horizontal Pipingrange
ft
581012151820
NOTE Ductile iron pipe is stiff enough to span its full laying length between supports at any size, so a support per length at the joint is structurally sufficient on a straight flanged run; a closer spacing is selected where the run carries valves and fittings that concentrate weight, where the pipe is to be grooved with flexible couplings, or where the owner's standards set a spacing for all piping regardless of material. The hanger standard carries no ductile iron spacing table, which is why the value is a project selection here rather than a reference to it. (14.1.5)
14.1.6 Each valve, flow meter, dismantling joint, and item of equipment shall be supported independently of the adjoining pipe, so that no joint carries the weight of the item and no item carries the weight of the pipe.
14.1.7 Vertical risers shall be supported at their base on a concrete pier or a riser clamp bearing on the structure, and shall be guided at intervals not greater than the horizontal support spacing.
14.1.8 Where exposed piping rests on concrete, the pipe shall bear on a saddle or stand of the material shown on the piping layout drawings, and no ductile iron pipe shall bear directly on concrete.
14.1.9 Where the parties disagree whether a support arrangement is adequate for a concentrated load, the Engineer of Record shall make the initial determination.

14.2 Equipment Connections

14.2.1 Piping at each equipment connection shall be aligned to the equipment nozzle with the bolts free in their holes and the flange faces parallel within the gasket manufacturer's tolerance before the gasket is placed, and the equipment shall not be used to draw the piping into alignment.
14.2.2 The removal joint required by this standard shall be installed between the equipment and the first fixed point in the piping, and its tie rods shall be loose until the adjacent flanges are bolted.
14.2.3 Piping shall be supported so that no weight, thrust, or thermal load is carried by a pump, valve, or equipment nozzle, and the manufacturer's published allowable nozzle load shall not be exceeded.
NOTE A pump volute is a casting with a published allowable nozzle load that is small compared with the weight of a length of flanged iron pipe, and a pipe pulled into alignment at the pump keeps pulling for the life of the plant. The misalignment shows up as a bearing or seal failure that the pump supplier attributes, correctly, to the piping. (14.2.4)
14.2.5 Connections to equipment shall be made in the sequence and with the isolation arrangement shown on the process mechanical plans and sections.

14.3 Expansion and Movement

14.3.1 Where exposed piping crosses an expansion joint in the structure or spans between two structures that can settle independently, a flexible joint capable of the movement shown on the piping layout drawings shall be provided at the crossing.
14.3.2 Thermal movement of long exposed runs shall be accommodated by the flexible couplings, expansion joints, or anchors shown on the piping layout drawings, and no flanged run longer than 100 ft shall be anchored at both ends without a provision for movement between them.
NOTE Ductile iron grows about 0.007 in. per foot per 100°F, which on a 200 ft outdoor header between a summer afternoon and a winter night is close to an inch. A flanged run clamped at both ends has nowhere to put that inch except into the flanges and the anchors, and the first thing that moves is the anchor bolt. (14.3.3)

14.4 Cleaning and Identification

14.4.1 The interior of exposed piping shall be kept clean during installation, and each run shall be flushed clean of debris before it is connected to equipment and before the pressure test.
14.4.2 Pipe markers, flow arrows, and valve tags shall be furnished and installed in accordance with Mechanical IdentificationMechanical IdentificationResolves to the current adopted revision.sync/mechanical-identification and ASME A13.1, after painting is complete.
14.4.3 The color scheme for process piping shall be as indicated on the piping color schedule.
NOTE State reviewers in most jurisdictions hold a water treatment plant to the pipe color scheme of the Ten States Standards, which assigns a color to each water, chemical, sludge, and gas service, and many owners have a scheme of their own; the schedule records which one the project follows, and the identification standard carries how the markers are made and placed. (14.4.4)

15 Installation of Buried Yard Piping

15.1 Trench and Laying Condition

15.1.1 Buried yard piping shall be installed in accordance with AWWA C600, in a trench excavated under EarthworkEarthworkResolves to the current adopted revision.sync/earthwork to the width and depth the laying condition and the depth of cover require.
15.1.2 The laying condition for the bedding and embedment of buried piping shall be as indicated in the datasheet, and the pipe wall design on the piping schedule shall be consistent with it.
Laying Condition per AWWA C150 and C600select
Type 1, flat-bottom trench, loose backfill
Type 2, flat-bottom trench, backfill lightly consolidated to the centerline
Type 3, pipe bedded in 4 in. of loose soil, backfill lightly consolidated to the top of the pipe
Type 4, pipe bedded in sand or gravel to the centerline, backfill compacted to the top of the pipe
Type 5, pipe bedded in compacted granular material to the centerline, backfill compacted to the top of the pipe
NOTE The laying condition is one of the two inputs to the wall thickness design of AWWA C150, the other being the depth of cover; the better the bedding supports the pipe, the thinner the wall the same cover requires. Type 2 is the condition most buried ductile iron has historically been designed for, and Type 4 and Type 5 are the conditions a plant with heavy traffic over its yard piping, deep cover, or poor native soil selects, at the cost of imported bedding. Type 1 is listed because the standard lists it; a wall designed for it is thick enough that nothing in the trench matters, and the condition is rarely specified on purpose. (15.1.3)
15.1.4 The depth of cover over each buried line shall be as shown on the yard piping plans and profiles, and the pipe wall on the piping schedule shall be designed for the maximum cover and surface load along that line.
15.1.5 The pipe zone, from the trench bottom to 12 in. above the top of the pipe, shall be bedded and backfilled under this standard, and backfill above the pipe zone shall be placed under EarthworkEarthworkResolves to the current adopted revision.sync/earthwork.
15.1.6 Bedding and pipe zone material shall be free of stones larger than 1-1/2 in., frozen material, and debris, placed and compacted in lifts not exceeding 6 in. to the laying condition selected.
15.1.7 Bell holes shall be excavated at each joint so that the pipe barrel bears on the bedding along its full length and the joint carries no load.
NOTE A pipe that rests on its bells is a beam supported at its ends, and the bending puts the joint in tension on the bottom and the barrel in bending it was never designed for. The bell hole is the difference between a pipe that bears on its length and one that bears on its joints. (15.1.8)
15.1.9 No pipe shall be laid in water or on a frozen trench bottom, and the trench shall be dewatered under EarthworkEarthworkResolves to the current adopted revision.sync/earthwork until the pipe zone is backfilled.

15.2 Laying, Deflection, and Protection

15.2.1 Pipe shall be laid with the bells facing the direction of laying, with the interior swabbed clean before each joint is made, and with the open end closed whenever laying is not in progress.
15.2.2 The alignment and grade of each line shall be held so that no unintended high point is created in a pressure line and so that the deflection at any joint does not exceed the manufacturer's published value for that joint and size.
15.2.3 Where the pipe wall is lined with a lining other than cement mortar, field cutting shall be done with a saw or a cutter that does not shatter the lining, and the cut end shall be beveled and the lining repaired before the joint is made.
15.2.4 Buried piping shall be installed with a detectable warning tape in the backfill 12 in. above the top of the pipe, and with a tracer wire where indicated on the yard piping plans.
NOTE Ductile iron pipe is located by a metal detector without a tracer wire, but polyethylene encasement and depth both weaken the signal, and a plant yard that will be excavated repeatedly for the life of the plant is the place a tracer wire pays for itself. The warning tape is the protection against the excavator that does not stop to locate anything. (15.2.5)
15.2.6 Buried valves shall be installed with a valve box or vault as shown on the yard piping plans, with the valve supported on a concrete pad so that the pipe does not carry the valve weight.
15.2.7 Backfill above the pipe zone shall not be placed over a buried fitting or thrust block until the restraint at that fitting is complete and, where a thrust block is used, until the concrete has reached the strength the thrust restraint design states.
15.2.8 The joints of buried piping shall be left exposed until the pressure test of that section is complete, unless the Engineer of Record approves in writing a test after backfill with the joints covered.
NOTE A buried joint that leaks under test is found by the water at the surface if the trench is open and by nothing at all if it is closed. Where the schedule demands backfill before the test, the test runs longer and the acceptance criterion is the measured leakage alone, which is the condition the approval records. (15.2.9)

16 Pressure and Leakage Testing

16.1 Test Sections and Pressure

16.1.1 Every line shall be hydrostatically tested in sections before buried piping is backfilled above the pipe zone, before exposed piping is painted or insulated, and before any line is placed in service.
16.1.2 The hydrostatic test pressure for each section shall be the multiple of the design working pressure indicated in the datasheet, measured at the lowest point of the section, and not less than the minimum test pressure indicated in the datasheet.
Hydrostatic Test Pressure, Multiple of Design Working Pressurerange
1.251.52
Hydrostatic Test Pressurerange
psi
50100125150200250300
Default: Not less than 150 psi
NOTE AWWA C600 sets the test at not less than 1.25 times the working pressure at the highest point of the section, and most plant specifications test at 1.5 times the design working pressure with a floor of 150 psi, which proves the joints and the restraint with a margin above the surge the design allows for. A test at twice the working pressure is selected for a high-service or high-lift discharge where the surge analysis shows transients approaching the design pressure. The floor is what keeps the test on a low-pressure gravity line, a plant drain or a settled water line, high enough to find a leaking joint at all. (16.1.3)
16.1.4 No section shall be tested at a pressure exceeding the pressure rating of the lowest-rated component within it, and a component rated below the calculated test pressure shall be isolated from the section and tested separately at its own rating.
16.1.5 Test sections and their boundaries shall be as recorded on the accepted pressure test plan, and a valve shall not be used as a test boundary unless it is rated for the test pressure as a closed valve with the differential across it.
16.1.6 Each section shall be filled slowly from its lowest point with potable water, with air vented from every high point, and shall stand filled for not less than 24 hours before the test pressure is applied where the section contains cement mortar lining.
NOTE A cement mortar lining absorbs water for the first day it is wet, and a section tested the hour it is filled shows a pressure drop that is the lining drinking, not a leak. The soak is what makes the measured leakage mean something. (16.1.7)
16.1.8 Thrust restraint for a section shall be complete, and where thrust blocks are used the concrete shall have reached the strength the restraint design states, before the test pressure is applied.

16.2 Hold Duration and Acceptance

16.2.1 The test pressure shall be held for not less than the duration indicated in the datasheet, during which the Contractor shall measure the volume of water added to maintain the test pressure within 5 psi of the specified pressure.
Test Hold Durationrange
hours
1248
Default: Not less than 2 hours
16.2.2 The leakage acceptance criterion for exposed piping shall be as indicated in the datasheet.
Leakage Acceptance, Exposed Pipingradio
● No visible leakage and no measurable makeup
○ Allowable leakage per AWWA C600
16.2.3 The leakage acceptance criterion for buried piping shall be as indicated in the datasheet.
Leakage Acceptance, Buried Pipingradio
● Allowable leakage per AWWA C600
○ No visible leakage and no measurable makeup
NOTE AWWA C600 allows a small makeup volume on a buried section, calculated from the length, the diameter, and the test pressure, because a gasketed joint under soil seeps slightly as it seats and because a long buried section cannot be inspected joint by joint. An exposed section can be inspected at every flange, so a zero criterion is both achievable and the only one that proves the flanges were made up correctly; a visible drip at a flange fails the test on an exposed run regardless of the measured volume. (16.2.4)
16.2.5 Where the allowable leakage of AWWA C600 is the criterion, the measured makeup volume shall not exceed the allowable leakage computed by the formula of that standard for the section tested, and visible leakage at any flanged joint shall fail the test regardless of the measured volume.
16.2.6 A section that fails shall be repaired, the cause corrected, and the complete test repeated from the beginning, and the Contractor shall bear the cost of the repair, the retest, the test water, and the repair of other work damaged by the failure or the water released.
16.2.7 Test gauges shall be calibrated within the preceding twelve months, shall have a range of 1.5 to 2 times the test pressure, and shall be graduated to resolve a change of 2 psi.
16.2.8 The pressure test shall be witnessed by the party indicated in the datasheet, and the Contractor shall give that party not less than three business days notice of each test.
Pressure Test Witnessselect
Engineer of Record or the Engineer's representative
Owner's representative
Authority Having Jurisdiction inspector
Contractor's quality control representative
NOTE The Engineer of Record is the witness on most plant projects because the test is the acceptance of the piping against the design the Engineer prepared. An owner's representative witnesses where the owner operates the plant and has its own inspection staff. The Authority Having Jurisdiction witnesses where the state health or environmental agency requires it before a potable line is placed in service, which is a condition of the permit rather than a project preference. The Contractor's own quality control representative is the witness only where the Contract Documents establish a quality control program the Engineer audits rather than attends. (16.2.9)
16.2.10 A signed and dated test report shall be prepared for every section, recording the section, the test pressure, the hold duration, the makeup volume or pressure change, the allowable leakage where applicable, the ambient and water temperatures, and the names and signatures of the Contractor's representative and the witness.
16.2.11 A test report shall not record a conditional or qualified pass, and a section in which a repair was made shall be recorded on a new report covering the complete repeat test.

17 Disinfection of Finished-Water Piping

17.1 Lines carrying finished water, potable water, or water that will become potable shall be disinfected in accordance with AWWA C651 after the pressure test and before the line is placed in service.
17.2 The disinfection method shall be as indicated in the datasheet.
Disinfection Methodselect
Continuous feed of chlorinated water
Tablet method
Slug method
NOTE The continuous-feed method fills the line with water chlorinated to a measured concentration and holds it, and it is the method of a plant line that can be filled from a chlorinated source and isolated, which most can. The tablet method places hypochlorite tablets in the pipe as it is laid and fills slowly, which suits a new line laid dry and cannot be used where the line is flushed before it is filled. The slug method passes a high-concentration slug through a long line and is the method of a main too long to hold full of chlorinated water, which is rare inside a plant. (17.3)
17.4 The disinfected line shall be flushed, the chlorinated water shall be dechlorinated or disposed of as the discharge permit requires, and bacteriological samples shall be collected and analyzed in accordance with AWWA C651 before the line is placed in service.
17.5 A line that fails the bacteriological test shall be re-disinfected and re-sampled at the Contractor's cost until two consecutive samples collected 24 hours apart pass.
17.6 Chlorinated water shall not be discharged to a receiving water, a storm drain, or a process unit without dechlorination and without the written acceptance of the party responsible for the discharge permit.
NOTE Lines carrying raw water, wastewater, sludge, scum, or chemicals require no disinfection, and the requirement is confined to the lines whose water reaches the distribution system. (17.7)

18 Warranty

18.1 The Contractor shall warrant the ductile iron process piping, including pipe, fittings, joints, gaskets, bolting, linings, coatings, couplings, wall pipes, and restraint, against defects in materials and workmanship for the period indicated in the datasheet, measured from the date of substantial completion.
Contractor Installation Warranty Periodrange
years
1235
Default: Not less than 1 years
18.2 Where the contract General Conditions specify a longer warranty period than the datasheet, the longer period shall govern.
18.3 Any leak, joint separation, lining failure, coating failure, or restraint failure attributable to the materials or the installation and discovered within the warranty period shall be repaired by the Contractor at no cost to the Owner.
18.4 The Contractor shall bear the cost of excavation, dewatering, backfill, paving, and finish work required to reach a warranted repair, and the cost of repairing damage caused by the failure or by the repair itself.
NOTE A warranted repair in buried yard piping is reached through the pavement, the backfill, and the groundwater between the surface and the joint, and that excavation is the cost the warranty is about. Naming it here is what keeps the repair from becoming a negotiation. (18.5)
18.6 A repaired or replaced portion of the piping shall carry a warranty running for a full new term from the date the repair is accepted, or for the remainder of the original term, whichever ends later.
18.7 The Contractor shall pressure test any repaired section in accordance with this standard before the repair is accepted.

19 Spare Parts

19.1 The Contractor shall furnish the spare parts indicated in the datasheet, delivered to the Owner before substantial completion, packaged, labeled by size and service, and listed on a receipt signed by the Owner's representative.
Spare Parts Furnishedcheckbox
☑ Flange gaskets, one set per size and service
☐ Flange bolt sets, one set per size and material
☐ Grooved coupling gaskets, one per size and compound
☐ Dismantling joint and coupling gaskets, one set per size
☑ Lining repair material, one kit per lining type
NOTE A gasket set and a lining repair kit are what an operator reaches for the first time a flange is opened or a lined pipe is cut, and neither is stocked locally in the elastomer and lining the project selected. The bolt sets and coupling gaskets are selected where the plant has no stores of its own or where the bolting material is a stainless grade the local supply does not carry. (19.2)