Storm Water: Cast Iron Soil Pipe

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Storm water drainage systems are networks of pipes and culverts designed to transport surface...

Cast iron soil pipe and fittings are used for gravity flow systems, primarily for drain, waste,...

Benefit of Material to Systems Application

Cast iron soil pipe is one of the most common materials for storm systems and provides several key benefits. One of its most important features is its strength. A hubless cast iron pipe 4” in diameter will support 4,877 pounds per linear foot without breaking. Cast iron pipe is also rigid, so deflection of the pipe wall is almost nonexistent. This piping system is also completely fireproof and will not support a fire or burn away.

Cast iron has also been shown to be the longest lasting pipe. It has been in use since the 1500’s so it has a long track record. Cast iron also has been shown to transmit the lowest amount of noise compared to other piping systems, making it the quietest pipe.  Cast iron soil pipe is priced relatively higher than other materials, such as ABS/DWV plastic pipe. However, the slightly high cost reference to cast iron soil pipe compared to other materials might be justified by the noise reduction when using cast iron.

System Application and Material Usage

Cast iron pipe and fittings are available in sizes ranging from 1 ½” to 15”. Hub and spigot or SV pipe is joined together by inserting an SV gasket into the hub and pushing a plain end piece of pipe into the hub. No Hub pipe is joined together by clamping the pipe together using a neoprene gasket housed inside a corrugated stainless steel shield. Stainless clamps surround the shield to provide the sealing force. Code requires that for above ground pipe there must be a support on either side of each coupling.  

In highly acidic situations, cast iron soil pipe may be a liability. According to the Cast Iron Soil Pipe Institute, strong acids (below pH 4.3) can cause internal corrosion of cast iron soil pipe if left in contact for an extended period of time without being diluted. An example of this would be a movie theater where a large amount of soda pop is poured down the waste line.

Manufacturers and Suppliers Participating in OPUS

AB&I Foundry

AB&I Foundry has been producing quality cast iron pipe and fittings for DWV plumbing......
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Charlotte Pipe & Foundry

Charlotte Pipe and Foundry Company has been a part of the plumbing industry for over 100 years.......
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F.W. Webb Company

F.W. Webb Company is a multi-faceted distributor of plumbing and heating, HVAC and controls,......
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Ferguson specializes in providing PVF, Plumbing, HVAC and Related Specialty Products and......
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Galloup Company

J.O. Galloup Company is a premier distributor of commercial and industrial piping products,......
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Hajoca Corporation

Founded in 1858, the Hajoca Corporation is the largest privately owned wholesale distributor of......
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Jomar Valve

Founded in 1966 by former Navy Commander Joseph Martin, Jomar Valve set out to change the way......
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MORSCO is a leading U.S. distributor of commercial and residential plumbing, HVAC, and PVF, with......
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The Commonwealth Group

The Commonwealth Group is the industry’s newest, 100-percent member owned, $8.5......
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Tyler Pipe & Coupling

 Tyler Pipe Company is a manufacturer of cast iron soil pipe, fittings, gaskets for hub and......
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Wade Drainage Products

Wade Drains is the oldest drain company in the United States. Founded in 1865 by J.J. Wade, it......
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Weldbend Corporation

Weldbend Corporation is a manufacturer of carbon steel welding fittings and forged steel......
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Applicable Joining Methods

Hubless Coupling

Also known as no-hub, hubless couplings connect hubless cast iron pipe with a rubber sleeve and...
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Special Topics

Green Construction

Cast iron pipe is typically made of 100% recycled materials. LEED credits may be available for recycled materials as well as use of regional products, depending on the project site's proximity to where the piping is manufactured.