AWWA C515 STANDARD / AWWA C509 STANDARD

Many engineers question the difference between AWWA C509 Standard for resilient seated gate

valves, and AWWA C515 Standard. Their concern is that the AWWA C515 Standard is

somehow for a “Thin Wall” or cheaper version of the valve. Sort of like the old axiom, “more is

better”. This simply is not the case.

Gate valves were first covered by the AWWA in Standard C500 in 1952. This Standard was for

metal-to-metal seated gate valves, commonly called “double disc”. These were cumbersome

valves and one can only imagine the problems caused with forcing two metal discs against a

metal seat.

AWWA Standard C509 first covered resilient Seated gate valves in 1985. The predominant

metal used to cast valves at that time was “Gray Cast Iron”. Therefore, the Standard was written

around this gray cast iron material, which has a tensile strength of 31,000 psi, no yield strength

whatsoever, and no capability for elongation.

AWWA C515 utilizes the far superior ductile iron as its design basis. To compare the two

materials briefly:

Material Tensile Strength Yield Strength Elongation

Gray Cast Iron 31,000 psi 31,000 psi 0%

Ductile Iron 65,000 psi 45,000 psi 12%

As ductile iron is more than 2x stronger than gray cast iron, the wall thickness of the valves does

not need to be anywhere near as thick to produce equal or superior performance of the valve in

all aspects.

Nom. Size (in.) AWWA C509 Wall Thickness (in.) AWWA C515 Wall Thickness (in.)*

3 .37 .30

4 .40 .31

6 .43 .32

8 .50 .34

10 .63 .36

12 .68 .38

16 .85 .50

*Thicker than AWWA C151 Class 52 Ductile Iron Pipe.

AWWA C515 also better defines the rubber materials used to obtain the resilient seat, including

the vulcanizing process. In addition, it recognizes the use of split thrust collars, and stainless

steel stems / bolting material.

2113 West 30th Street, Jacksonville, FL 32209 Tel: 877-766-4459 Fax: 877-766-4458 Cell: 904-910-3902

pgray@unitedwaterproducts.com

To summarize, AWWA C509 is a Standard for valves that is approaching a quarter century since

its inception, and was adopted for valves made out of gray cast iron, a material rarely used

nowadays in pressure fittings and vessels for AWWA applications. AWWA C515 was adopted

to recognize the superior performance characteristics and strength of ductile iron, and is a better

defined Standard, referencing more modern technology.

An analogy can be made between AWWA ductile iron resilient seated valves and AWWA water

main fittings. The “old style” “full body” AWWA C110 fitting, made from gray cast iron, is

virtually a thing of the past in the waterworks industry. It has been replaced by “Compact

Ductile Iron Fittings” made to AWWA C153 Standard. The same can be said for resilient seated

valves. AWWA C515 valves of a more efficient design are replacing the “Old Style” gray cast

iron AWWA C509 valves.

With regard to the UNITED MODEL 2010 AWWA C515 RESILIENT SEATED GATE

VALVE, the proof is in the design and independent test results. It is the only AWWA C509 or

C515 valve that is UL Listed at 300 psi and FM Approved at 250 psi (4”-12” sizes). Further

advantages include:

Stainless Steel Stem as Standard

Stainless Steel Studs / Bonnet Fasteners, no exposed nuts.

EPDM Rubber Seat Bonded to Wedge / Disc

DuPont Fusion Bonded Epoxy Coating (AWWA C550), NSF-61

All surfaces Fusion Bonded Epoxy Coated after machining. No exposed metal surface.

Triple O-Ring Seal (Bonnet, Cap, Stem)

SPECIFY THE LATEST IN VALVE PERFORMANCE AND TECHNOLOGY – THE

UNITED MODEL 2010 AWWA C515 RESILIENT SEATED GATE VALVE.