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Restrained Joint Pipe

Grooved and Shouldered Joints

The AMERICAN grooved joint, furnished in sizes 4" to 36", and the AMERICAN shouldered joint, furnished in sizes 18" to 64", are fabricated joints most often used in plant piping installations.

These joints are sometimes alternatives to the flanged joint, and they are suitable for all specified applications, such as those found in treatment plants and pump stations.

Both joints meet all applicable requirements of AWWA C606.

Available in both flexible and rigid designs, grooved and shouldered joints offer quick assembly. If a field-grooving machine is available, the field adaptability of grooved pipe may be advantageous.

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Standards

Summary of Standards

for Ductile Iron Pipe and Ductile Iron Fittings

Most of the standards covering pipe and fittings manufactured by American Cast Iron Pipe Company have been prepared by the American Water Works Association Standards Committee A21. Other applicable standards generally cover specialties or refer to ANSI standards.

In order to take advantage of modern metallurgical science, better testing methods, improved production control, materials with better physical properties, and improvements in manufacturing methods, the A21 Committee has a continuing program for keeping its standards revised to include the latest proven developments.

Development of Standards

The AWWA Standards Committee A21 on Ductile and Gray Iron Pipe and Fittings was organized in 1926 under the procedures of the American Engineering Standards Committee. It was reorganized under American Standards Association Procedures in 1955, and in 1984 it became a member of the AWWA committee structure.

The Committee is responsible for the development of standards and manuals for ductile iron pressure pipe for water and other liquids and for fittings used with such pipe. The Committee’s membership is comprised of representatives from consumer groups, producer groups and general interest groups, including a number of professionals from AMERICAN.

A standard, manual or revision is developed by a subcommittee assigned to that task. The subcommittee prepares and submits the document to the Standards Committee for approval. After approval it is then submitted to the AWWA Standards Council for approval. After all approvals have been received, including a public review by both AWWA and ANSI, the standard, manual or revision is published and made available to the public.

Abbreviations of Organizations

AASHTO

American Association of State Highway and Transportation Officials

ACI

Alloy Casting Institute

AISI

American Iron and Steel Institute

ANSI

American National Standards Institute

API

American Petroleum Institute

ASCE

American Society of Civil Engineers

ASME

American Society of Mechanical Engineers

ASTM

American Society for Testing and Materials

AWWA

American Water Works Association

BSI

British Standards Institute

DIPRA

Ductile Iron Pipe Research Association

DIS

Ductile Iron Society

FM

FM Global

ISO

International Organization for Standardization

MIL

United States Military

NEWWA

New England Water Works Association

NSF

NSF International

UL

Underwriters Laboratories

WEF

Water Environment Federation

Specification History

A brief review of the older specifications in chronological order may help define their usefulness, as well as help in the appreciation of the improved modern standards.

The basis for design in almost all specifications to date is the Barlow formula, or “Hoop Stress” formula. It embodies the basic principle for design of a cylinder for internal pressure. The formula may be stated as:

in which t is the thickness of the pipe in inches; P is the internal pressure in pounds per square inch (psi); D is the outside diameter in inches; and S is the allowable working stress of the metal in pounds per square inch.

In the development of the design of cast iron pipe, this formula has been modified in several ways by prominent water works engineers such as Allen Hazen, Thomas H. Wiggin, James T. Fanning, Dexter Brackett, I. J. Fairchild and James P. Kirkwood. Mr. Kirkwood, as chief engineer for the Brooklyn Water Works, developed a design for cast iron pipe which was a variant of the Barlow formula. Kirkwood’s calculations took into consideration casting imperfection, strength of the metal and other factors affecting the life of the pipe. In the late 1880s, a formula by Dexter Brackett, distribution engineer for the City of Boston, was adopted by the New England Water Works Association as their standard.

Although the 1902 NEWWA standards did not provide a formula for pipe thicknesses, the Brackett formula was used in determining the thicknesses recommended.

The AWWA in 1908 adopted a standard covering bell and spigot pipe produced in 12-foot laying lengths by the pit casting method. Prior to 1908, at least two unofficial documents dealing with pipe design were acknowledged by AWWA. The first of these used thicknesses for pipe determined by averaging the thicknesses used in a large number of American cities. The second dealt with actual design of pipe based on Brackett’s method with variations.

The 1908 AWWA standards employed a system of class designations applied to specific wall thicknesses in diameters 4" through 84" inclusive for a range of hydraulic heads. The most common of these classes were A, B, C and D for 100-, 200-, 300- and 400-feet hydraulic head, respectively. The design was based on a variation of the Brackett formula by J. T. Fanning and included a variation in the outside diameter for the different classes of pipe. The basic design of pipe with a different outside diameter for each class was followed in modern specifications until the 1961 revisions. The general acceptance by the water works industry of the standardized mechanical joint necessitated a universal outside diameter for cast iron pipe.

AWWA ;revised their standards in 1939 to incorporate a new method of designing cast iron pressure pipe. This new method was published as ANSI A21.1. The A21.1 method of determining the required thickness of cast iron pipe took into consideration trench load and internal pressure in combination. Trench load consists of the earth load on the pipe plus any transient load resulting from traffic over the trench; internal pressure consists of the design working pressure plus an additional allowance for surge pressure. Laying conditions and properties of the iron in the pipe are also factors involved in the design. Additions for casting tolerance are included in the design thickness. With the advent of ductile iron pipe and its flexibility, this additive method of design became obsolete. As noted in the following paragraph, ductile iron design employs flexible conduit principles since the internal pressure relieves the external load.

Actually, the first standard covering centrifugally cast pipe was issued by the U.S. government in 1927, and was known as the Federal Specification No. 537. In July 1931, the specification was revised to include pipe cast centrifugally in sand-lined molds, pipe cast centrifugally in metal molds, and pit cast pipe. This specification has been modified several times and is now basically the same as ANSI/AWWA Standards.

Development of ductile iron in the 1950s initiated research into design of ductile iron pipe to take advantage of the superior flexibility, strength, toughness, impact resistance and corrosion resistance of this new metal. The A21 Committee issued the ANSI A21.50 (AWWA H3-65) and ANSI A21.51 (AWWA C151) Standards for ductile iron pipe in 1965. The work of Prof. M. G. Spangler and others at Iowa State University on flexible conduit is the basis for principles that have been applied extensively by the designers of flexible underground pipe. The design principles and procedures for ductile iron pipe that were included in the ANSI Standard A21.50 (AWWA C150) were verified by actual trench tests at AMERICAN and by tests conducted by various researchers. AMERICAN’s technical director, Dr. Ed Sears, was instrumental in these developments.

Continued research on ductile iron pipe reflects through these updated standards the advancements in metallurgical technology and manufacturing skills. Furthermore, the quality of AMERICAN’s products and conformance to appropriate specifications are assured by the British Standards Institute’s certification that AMERICAN’s quality system complies with ISO 9001 Quality Management System Standard.

AMERICAN also subscribes to NSF’s listing program for products under ANSI/NSF Standard 61—Drinking Water System Components—Health Effects. Check with AMERICAN for current listing of our products.

Standards Applicable to AMERICAN Pipe and Fittings

Ductile Iron Pipe for Water and Other Liquids

Standards

4" through 64"

ANSI/AWWA C150/A21.50
ANSI/AWWA C151/A21.51

Ductile Iron Gravity Sewer Pipe

Standards

4" through 64"

ASTM A746

Ductile Iron Culvert Pipe

Standards

14" through 64"

ASTM A716

Ductile and Gray Iron Fittings for Water and Other Liquids

Standards

4" through 48"

ANSI/AWWA
C110/A21.10

Ductile Iron Compact Fittings

Standards

4" through 64"

ANSI/AWWA C153/A21.53

Flanged Pipe

Standards

4" through 64"

ANSI/AWWA C115/A21.15

Coatings and Linings

Standards

Asphaltic

ANSI/AWWA C110/A21.10
ANSI/AWWA C115/A21.15
ANSI/AWWA C151/A21.51
ANSI/AWWA C153/A21.53

Cement Lining

ANSI/AWWA C104/A21.4

Fusion-Bonded Epoxy

ANSI/AWWA C116/A21.16

Ceramic Epoxy Lining

ASTM A716/A746

Coal Tar Epoxy Lining

Contact AMERICAN

Polyethylene Encasement

ANSI/AWWA C105/A21.5
ASTM A674

Joints — Pipe and Fittings

Standards

Fastite

ANSI/AWWA C111/A21.11

Mechanical

ANSI/AWWA C111/A21.11

Flanged

ANSI/AWWA C110/A21.10
ANSI/AWWA C115/A21.15
ANSI/AWWA C153/A21.53

Grooved and Shouldered

AWWA C606

Other joints shown in this section are AMERICAN design.

All Products1

ANSI/NSF Standard 61

NOTE: Many AMERICAN joints, classes of pipe, fittings and specials are listed by Underwriters Laboratories Inc. and FM Global. The quality of AMERICAN’s products and conformance to appropriate specifications are assured by the British Standards Institute’s certification that AMERICAN’s quality system complies with ISO 9001 Quality Management System Standard.

Standards for the Design, Manufacture, Installation and Certification of Ductile Iron Pipe and Ductile Iron Fittings

Standard Designation

Subject

ANSI/AWWA C104/A21.4

Cement-Mortar Lining for Ductile-Iron Pipe and Fittings for Water

ANSI/AWWA C105/A21.5

Polyethylene Encasement for Ductile-Iron Pipe Systems

ANSI/AWWA C110/A21.10

Ductile-Iron and Gray-Iron Fittings, 3 in. through 48 in., for Water

ANSI/AWWA C111/A21.11

Rubber-Gasket Joints for Ductile-Iron Pressure Pipe and Fittings

ANSI/AWWA C115/A21.15

Flanged Ductile-Iron Pipe with Ductile-Iron or Gray-Iron Threaded Flanges

ANSI/AWWA C116/A21.16

Protective Fusion-Bonded Epoxy Coatings for the Interior and Exterior Surfaces of Ductile-Iron and Gray-Iron Fittings for Water Supply Service

ANSI/AWWA C150/A21.50

Thickness Design of Ductile-Iron Pipe

ANSI/AWWA C151/A21.51

Ductile-Iron Pipe, Centrifugally Cast for Water

ANSI/AWWA C153/A21.53

Ductile-Iron Compact Fittings, for Water Service

ANSI/AWWA C600

Installation of Ductile-Iron Water Mains and Their Appurtenances

ANSI/AWWA C606

Grooved and Shouldered Joints

ASTM A674

Polyethylene Encasement for Ductile Iron Pipe for Water or Other Liquids

ASTM A716

Ductile Iron Culvert Pipe

ASTM A746

Ductile Iron Gravity Sewer Pipe

ANSI/NSF 61

Drinking Water System Components—Health Effects

ASTM G62

Standard Test Methods for Holiday Detection in Pipeline Coatings

Miscellaneous Standards

The following standards are related to ductile iron and gray iron piping and other products, but are generally not directly applicable to the manufacture of AMERICAN pipe and fittings.

Standard Designation

Subject

ANSI A40.5

Threaded Cast-Iron Pipe for Drainage, Vent, and Waste Services

ANSI/ASME B1.1

Unified Inch Screw Threads (UN and UNR Thread Form)

ANSI/ASME B16.1

Cast Iron Pipe Flanges and Flanged Fittings, Class 25, 125, 250 and 800

ANSI/ASME B16.3

Malleable-Iron Threaded Fittings, 150 and 300 lb.

ANSI/ASME B16.4

Cast-Iron Screwed Fittings, 125 and 250 lb.

ANSI/ASME B16.5

Pipe Flanges and Flanged Fittings

ANSI B16.12

Cast Iron Threaded Drainage Fittings

ANSI B16.14

Ferrous Pipe Plugs, Bushings, and Lock-nuts with Pipe Threads

ANSI B16.21

Nonmetallic Flat Gaskets for Pipe Flanges

ASME/ANSI B16.42

Ductile Iron Pipe Flanges and Flanged Fittings

ANSI B18.2.1

Square and Hex Bolts and Screws (Inch Series)

ANSI/ASME B18.2.2

Square and Hex Nuts (Inch Series)

ANSI B31.1

Power Piping

ANSI/ASME B31.8

Gas Transmission and Distribution Piping Systems

ANSI/ASME B1.20.1

General Purpose Pipe Threads

ANSI/AWWA C207

Steel Pipe Flanges for Waterworks Service, 4” through 144”

ANSI/AWWA C500

Gate Valves, 3” through 48” NPS for Water and Sewage Systems

ANSI/AWWA C501

Sluice Gates

ANSI/AWWA C502

Dry-Barrel Fire Hydrants

ANSI/AWWA C503

Wet-Barrel Fire Hydrants

ANSI/AWWA C504

Rubber-Seated Butterfly Valves

ANSI/AWWA C508

Swing-Check Valves for Ordinary Waterworks Service

ANSI/AWWA C509

Resilient-Seated Gate Valves for Water and Sewage Systems

ANSI/AWWA C550

Protective Interior Coatings for Valves and Hydrants

ASTM A48

Gray Iron Castings

ASTM A74

Cast Iron Soil Pipe and Fittings

ASTM A126

Gray Iron Castings for Valves, Flanges, and Pipe Fittings

ASTM A278

Gray Iron Castings for Pressure-Containing Parts for Temperatures Up to 650°F (345°C)

ASTM A319

Gray Iron Castings for Elevated Temperatures for Non-Pressure Containing Parts

ASTM A377

Standard Index of Specifications for Ductile Iron Pressure Pipe

ASTM A395

Ferritic Ductile Iron Pressure Retaining Castings for Use at Elevated Temperatures

ASTM A438

Transverse Testing of Gray Cast Iron

ASTM A476

Ductile Iron Castings for Paper Mill Dryer Rolls

ASTM A518

Corrosion-Resistant High-Silicon Iron Castings

ASTM A536

Ductile Iron Castings

ASTM A571

Austenitic Ductile Iron Castings for Pressure Containing Parts Suitable for Low-Temperature Service

ASTM C150

Portland Cement

ASTM D1248

Polyethylene Plastic Molding and Extrusion Materials

ASTM E8

Tension Testing of Metallic Materials

AASHTO M64

Cast Iron Culvert Pipe

AASHTO M105

Gray Iron Castings

AWWA D100

AWWA Standard for Welded Steel Tanks for Water Storage

1.) Check with AMERICAN for current NSF listing of AMERICAN products.

Product Line Information

Domestic Certification
Submittals
Pipe Manual
Project Mgt/customer Service
Standards
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