Process Piping: Stainless Steel Pipe

Image provided by Victaulic

Process piping involves non-hydronic piping systems, generally used to convey chemicals. When...

Stainless steel defines a class of ferrous metals with high alloy content to enhance certain...

Benefit of Material to Systems Application

Stainless steel pipe is attractive for process piping systems primarily for its cleanliness and corrosion resistant properties. It is the material of choice for various food conveying applications which require conformance to FDA requirements. An inherent benefit of the stainless steel family of materials is that it covers materials of many different chemistries, permitting economical alternatives to higher end alloys and providing greater corrosion resistance to a wide variety of chemical services and environments, as well as providing increased material strength. 

The versatility and internal pressure capabilities make stainless steel pipe suitable for use in structures from one story to high rise buildings and industrial applications. In systems where corrosion resistance is not required, carbon steel is a less expensive option.

System Application and Material Usage

Process piping fluids cover a wide range of applications from water to chemical services.  For high pressure applications or highly corrosive environments, it may be necessary to utilize a duplex or super duplex stainless steel because of its increased physical properties and greater corrosion resistance.

Duplex stainless steel differs from austenitic stainless steel in chemical make-up; it has higher quantities of chromium and molybdenum and lower quantities of nickel. Duplex stainless steel can be referred to as 2205, and super duplex 2507 because of the percentages of chromium and nickel in their composition. All stainless steels contain a varying percentage of chromium, molybdenum and nickel.

The most common "family" of stainless steel is austenitic, which includes the stainless steel pipes made to the specifications of ASTM A312 in Types 304/304L and 316/316L. Types 304/304L are for general corrosion applications such as process cooling water. Types 316/316L have a higher corrosion resistance to chlorides and may be desired based upon the chemical composition of the process fluid. The “L” designation means that the stainless steel contains less than 0.03% carbon. This is beneficial if the pipe needs to be welded.

Stainless steel pipe is generally available in diameters up to 36 inches with dimensions ranging from Schedule 5S to 160S with Schedule 10S being the most common. Schedule designations indicate the pressure capacity the pipe. When specifying the Schedule of stainless steel pipe, an “S” is added after the Schedule number to differentiate stainless steel from other steel pipe.

The system working pressure and pipe joining method will determine the required pipe wall thickness for each application.

Stainless steel pipe may be installed using a variety of joining methods including grooved, welded, flanged, threaded and other mechanical joining methods. Ductile iron couplings may be used for process piping applications because the gasket material prevents any contact of the fluid to the coupling to maintain a sanitary environment.

An additional source for general information on stainless steel is http://www.stainless-steel-world.net/.

Manufacturers and Suppliers Participating in OPUS

F.W. Webb Company

F.W. Webb Company is a multi-faceted distributor of plumbing and heating, HVAC and controls,......
(click for details)


Ferguson specializes in providing PVF, Plumbing, HVAC and Related Specialty Products and......
(click for details)

Galloup Company

J.O. Galloup Company is a premier distributor of commercial and industrial piping products,......
(click for details)

Hajoca Corporation

Founded in 1858, the Hajoca Corporation is the largest privately owned wholesale distributor of......
(click for details)

Jomar Valve

Founded in 1966 by former Navy Commander Joseph Martin, Jomar Valve set out to change the way......
(click for details)

Metraflex Company

For over 55years Metraflex has met the needs of the contractor. The MetraLoop, a flexible pipe......
(click for details)


MORSCO is a leading U.S. distributor of commercial and residential plumbing, HVAC, and PVF, with......
(click for details)

Team Industries, Inc.

Team Industries, Inc. offers a 3000# Generation III and 3000# Generation IV (hydraulically......
(click for details)

The Commonwealth Group

The Commonwealth Group is the industry’s newest, 100-percent member owned, $8.5......
(click for details)

Tri Tool Inc.

Tri Tool Inc. designs and manufactures cutting and prepping tools for pipe and tube from .12 to......
(click for details)


Victaulic is the world's leading manufacturer of mechanical pipe joining products. For over 80......
(click for details)


Founded in 1899, Viega manufactures and distributes the highest quality plumbing, heating and......
(click for details)

Weldbend Corporation

Weldbend Corporation is a manufacturer of carbon steel welding fittings and forged steel......
(click for details)


WinWholesale, Inc. is comprised of over 525 wholesale distribution locations. Along with Noland......
(click for details)

Applicable Joining Methods


 Flanging may be used for threaded or plain-end pipe. After a flange component is installed...
(click for details)


Grooved pipe joints consist of two grooved pipe ends (typically roll grooved) connected with a...
(click for details)


Press joining is a form of mechanical connection for copper and steel tubing which uses a press...
(click for details)


 A threaded pipe connection involves an internal threaded fitting and an external threaded...
(click for details)


Welding is generally defined as the act of joining together two or more components by heating...
(click for details)