What material should a check valve be for chemicals?

316 stainless steel or PVC, with a Viton (FKM) or PTFE seal. Brass is not suitable for aggressive chemicals or high-chloride water.

Brass or stainless check valve?

Brass for water, air, oil, and general plumbing where it is economical. 316 stainless for chemicals, marine and high-chloride service, high purity, and higher temperatures and pressures.

When should I use a PVC check valve?

For water treatment, chlorine and sodium hypochlorite, acids, and other corrosive service where metal would corrode, as long as temperature and pressure stay within PVC limits.

Check Valve Material Selection

Two choices decide whether a check valve survives your system: the body material and the seal (seat) material. Get the body right for pressure, temperature, and corrosion; get the seal right for your specific fluid.

Body materials

Material	Best for	Avoid for
Brass	Water, air, oil, fuel, general plumbing. Economical and durable.	Aggressive chemicals, high-chloride or salt water, deionized water.
316 stainless	Chemicals, marine and high-chloride, high purity, higher temperature and pressure.	Mainly ruled out by cost when brass would do.
PVC	Water treatment, chlorine and sodium hypochlorite, acids, corrosive service.	Hot fluids and high pressure; PVC has lower limits.
Ductile iron	Large water mains, fire protection, HVAC, municipal lines.	Small-parcel jobs and aggressive chemicals; ships as freight.

Seal (seat) materials

Buna-N (NBR) - water, oil, air, fuel. The economical default for non-aggressive media.
Viton (FKM) - aggressive chemicals, fuels, and higher temperatures. The go-to for chemical service.
EPDM - hot water, steam, and many acids and bases; not for petroleum oils.
PTFE - the broadest chemical resistance, for the harshest media.

Full detail in the Valve Seat Material Guide.

How to choose in three questions

1. What is the fluid? Water, air, or oil points to brass with a Buna-N seal. Chemicals, chlorine, or salt water points to 316 stainless or PVC with a Viton or PTFE seal.

2. How hot and how much pressure? Higher temperature and pressure favor stainless or brass over PVC.

3. How big is the line? Small-parcel threaded and inline sizes come in brass, stainless, and PVC. Large lines move to ductile iron, which ships as freight.

Shop by material

Browse brass check valves, stainless steel check valves, or PVC check valves, or start from the check valve selection guide.

Technical data disclaimer: Specifications, dimensions, pressure/temperature ratings, and compatibility information on this page are compiled from manufacturer publications and are provided for reference only. Always verify suitability for your application against the manufacturer’s current documentation before purchase or installation. Apex Flow Solutions assumes no liability for errors, omissions, or misapplication of this information.