Ductile Iron Castings
Ductile Iron Castings
Ductile Iron Castings
STANDARD SPECIFICATIONS
SECTION 15056
PART 1 - GENERAL
A. Description
This section includes materials, installation, and testing of ductile-iron pipe and fittings.
All related work specified elsewhere, or in other codes or standards, will be as last revised, unless a
specific date of issuance is called out in opposition to later revision date(s).
Other sections of the technical specifications, not referenced below, shall also apply to the extent
required for proper performance of this work.
2. Concrete: 03300
C. Approved Manufacturers
1. Fittings
Per VWD Approved Material List, latest edition.
2. Pipe
Per VWD Approved Material List, latest edition.
3. Gaskets
Per VWD Approved Material List, latest edition.
PART 2 - MATERIALS
A. Ductile-Iron Pipe
1. Pressure class or thickness class of DIP shall be determined by the design method detailed
in AWWA C150 the "Thickness Design Method."
3. All ductile-iron pipe shall be pressure class shown on the plans for bell and spigot pipe,
pressure class 350 for plain end pipe and thickness Class 53 for flanged spools unless
indicated otherwise.
4. All domestic water ductile-iron pipe shall be cement-mortar lined in accordance with
AWWA C104. Lining thickness shall be the double thickness listed in AWWA C104,
Section 4.8.
5. Unless otherwise called out on the plans, a "push-on" type joint shall be used. The joint
dimensions and gasket shall be as specified in AWWA C111.
6. Where restrained joints are called for on 8-inches in diameter and smaller pipe, push-on
joints shall be restrained with locking gasket rated for 250 psi operating pressure. Joint
restraint shall be push-on joint with "Field-Lok" gaskets as manufactured by U.S. Pipe,
Perma-Lock Joint as manufactured by Pacific States Cast Iron Pipe Company or
approved equal. "TR-Flex" restrained joint pipe as manufactured by U.S. Pipe or
approved equal is also an acceptable option for restraint of push-on joints.
Where restrained joints are called for on 10-inches in diameter and larger pipe, use a
“TR-Flex” restrained joint pipe as manufactured by U.S. Pipe or approved equal. The
restrained joint shall be a boltless restrained push-on joint design and shall contain a
positive axial locking restrained system and be capable of deflection after assembly.
Restraint of field cut pipe by using U.S. Pipe’s “TR Flex Gripper Ring” or approved
equal will be permitted as long as the “TR Flex” pipe field weldments are not required.
Any restrained joint fitting which will require a pipe field weldment will not be permitted
under any circumstances. Restraint of field cut pipe shall be kept to a minimum.
7. Flanges for ductile-iron pipe shall be the "screwed-on" type in accordance with AWWA
C115.
9. All field cutburied ductile iron pipe for domestic water use shall have a factory applied
bituminous coating of not less than 1 mil. Thickness per approved material list
10. All ductile iron pipe and fittings approved for use in sewer applications shall be
polyurethane or polyethylene lined.
B. Ductile-Iron Fittings
2. All domestic water fittings shall be cement-mortar lined in accordance with AWWA C104.
Lining thickness shall be the double thickness listed in AWWA C104, Section 4.8.
3. All fittings shall be made with "push-on" or MJ joints designed for use with the type of
pipe to be joined unless noted otherwise.
4. Restrained push-on joint fittings shall be used only as shown on the plans. For pipe sizes
8-inches in diameter and smaller, push-on joint fittings shall be restrained with locking
gasket rated for 250 psi operating pressure. Joint restraint shall be push-on joint with
"Field-Lok" gaskets as manufactured by U.S. Pipe, Perma-Lock Joint as manufactured by
Pacific States Cast Iron Pipe Company or approved equal. "TR-Flex" restrained joint
fitting as manufactured by U.S. Pipe or approved equal is also an acceptable option for
restraint of push-on joint fittings in this size.
For pipe sizes 10-inches in diameter and larger, restrained joint fittings shall either be
“TR-Flex” restrained joint fitting as manufactured by U.S. Pipe or approved equal, or
mechanical joint ductile iron fittings fitted with joint restraints. Mechanical joint restraint
shall be incorporated with the design of the follower gland and shall include a restraining
mechanism which, when activated, imparts multiple wedging action against the pipe,
increasing its resistance as the pressure increases. The joint shall maintain flexibility
after burial. Follower glands shall be manufactured of ductile iron conforming to ASTM
A536-80. The mechanical joint restraint shall be EBBA IRON, Inc., MEGALUG,
UNIFLANGE Series 1400, The Ford Meter Box Co., Inc. or approved equal. Any
restrained joint fitting which will require a pipe field weldment will not be permitted.
5. Unless otherwise indicated on the drawings, all fittings with flanged ends shall be ductile
iron class 150. The gasket surface shall have a serrated finish of approximately 16
serrations per inch, approximately 1/32-inch deep, with serrations in either a concentric or
spiral pattern. All flanges shall be flat faced. In addition, all flanges shall meet the
following tolerances:
C. Gaskets
Rubber gaskets for push-on joints shall be synthetic or natural rubber manufactured in
accordance with AWWA C111.
1. All bolts and nuts shall conform to ASTM A 307, zinc plated.
2. The length of each bolt or stud shall be such that between 1/4 inch and 3/8 inch will project
through the nut when drawn tight.
E. Polyethylene Lining
1. Lining material for ductile iron pipe and fittings (sewer applications) shall be polyethylene
complying with ASTM D1248 and bonded to the interior of the pipe fittings by heat
process. The lining material shall be compounded with inert filler and a compound which
resists ultraviolet light.
2. The lining shall cover the interior surface of the pipe/fitting from the lain or beveled end to
the rear of the gasket socket. The lining thickness shall be not less than 20 mils. The lining
may taper at the ends, starting at 4 inches from the edge of the pipe. The minimum
thickness at the end of the taper shall be 10 mils.
3. Each pipe shall be guaranteed against separation of the lining from the pipe. Random
checks for operation will be made during construction and any indication of separation
shall be cause for rejection. The test method shall be mutually agreed upon by the
contractor and the District.
2. In order to minimize potential dimensional and assembly problems, the coating thickness
on sealing areas in the bell socket interior and on the spigot end of the pipe exterior shall
be 8 mils (0.008 inch) nominal with a maximum of 10 mils (0.010 inch). Thicker
coatings in these areas are acceptable if it is demonstrated that joint dimensions are
within allowable tolerances after coatings.
3. The lining material shall be applied to the pipe and fittings by a certified applicator only.
The coating shall be holiday tested with a high voltage tester at 50 volts/mil of material
thickness. The material shall be applied and repaired to the pipes and fittings in strict
accordance with the manufacturer’s requirements with no exceptions. District shall be
notified five (5) days in advance of the coating installation for factory inspection during
the application of the material.
4. All field cut ends shall be repaired and sealed prior to installation per the manufacturer’s
recommendations.
G. Lubricants
PART 3 - EXECUTION
A. General
Ductile-iron pipe and ductile iron fittings shall be installed in accordance with the applicable
Sections of AWWA C600 and as specified herein.
1. Trenching, backfilling, and compacting shall be in accordance with Section 02223 and as
specified herein.
2. Backfill within the pipe zone, including the pipe base, shall be imported sand placed and
compacted in accordance with Section 02223.
3. Backfill within the trench zone within VWD easement shall be native earth backfill placed
and compacted in accordance with Section 02223 or governing agency requirements.
2. The radius of curvature of the trench shall determine the maximum length of pipe section
that can be used without exceeding the allowable deflection at a joint. Combined
deflections at rubber gasket, restrained joint, deflection coupling or flexible coupling joints
shall not exceed 2 degrees.
3. The pipe shall be laid true to the line and grade shown on the plans.
All ductile-iron pipe and fittings buried underground shall be double wrapped based. with
plastic film wrap in accordance with AWWA C105, unless noted otherwise below. Wrap
shall be a loose 8-mil-thick clear polyethylene tube. All joints between plastic tubes shall
be wrapped with 2-inch-wide polyethylene adhesive tape, Polyken 900, Scotch wrap 50, or
approved equal.
6. Until thrust blocks and supports are poured, fittings shall be temporarily supported by
placing wooden skids under the bells so that the pipe is not subjected to the weight of the
fitting. Temporary supports to be removed just prior to pouring of thrust blocks.
7. All exposed flanges and other metal surfaces and all damaged coatings shall be coated after
assembly with a mastic, Minnesota Mining and Manufacturing EC 244, Koppers (Super-
Tank) 505, or an approved equal.
Concrete anchors and thrust blocks shall be poured against wetted undisturbed soil in accordance
with Section 03300 and VWD standard drawing W-15.
E. Flanged Connections
1. Bolt holes of flanges shall straddle the horizontal and vertical centerlines of the pipe run.
3. Clean flange bolts and nuts by wire brushing, lubricate threads with anti-seize compound,
and tighten nuts uniformly and progressively. Between 1/4 inch and 3/8 inch shall project
through the nut when drawn tight.
4. If flanges leak under pressure testing, loosen or remove the nuts and bolts, reseat or replace
the gasket, reinstall or retighten the bolts and nuts, and retest the joints. Joints shall be
watertight.
F. Pipe Support
G. Disinfection
All domestic water piping shall be disinfected by chlorination in accordance with Section 15041.
H. Testing
All domestic water piping shall be hydrostatically pressure tested in accordance with Section 15042.
I. Bonding
Bonding of joints to provide continuity for cathodic protection shall be as specifically shown on the
project plans, or directed by the District representative.
END OF SECTION