Valves
Strainers and flame arrestors
Strainers protect pumps, meters and control valves from debris; flame arrestors stop a flame front travelling through a vent or pipeline into a tank or process system. CRS PLUS sources Y-type, basket and temporary strainers and end-of-line and in-line flame arrestors, quoted by size, rating, screen or element, gas group and material.
Items we quote
Sourced through the qualified supplier base. Sizes, ratings and grades are shown as ranges; send your bill of materials and every line is quoted against its exact specification.
| Product | Standard | Sizes | Rating | Materials |
|---|---|---|---|---|
| Y-type strainer, flanged or socket-weld | ASME B16.34 / manufacturer | NPS ½ to 24 | Class 150 to 1500 | A216 WCB, A105N, A351 CF8M; SS316 screen |
| Simplex basket strainer | ASME B16.34 / manufacturer | NPS 1 to 24 | Class 150 to 600 | A216 WCB, fabricated CS, SS316 |
| Duplex basket strainer (switchable) | ASME B16.34 / manufacturer | NPS 1 to 16 | Class 150 to 300 | A216 WCB, fabricated CS, SS316 |
| Temporary cone / T-type strainer | Manufacturer | NPS 2 to 36 | To suit flange class | SS304 / SS316 perforated plate and mesh |
| End-of-line flame arrestor (tank vent) | ISO 16852 | NPS 2 to 12 | Atmospheric; gas groups IIA to IIC | Aluminium, carbon steel, SS316 element |
| In-line deflagration / detonation flame arrestor | ISO 16852 | NPS ½ to 24 | Class 150 to 300 flanges | Carbon steel, SS316 body and element |
How a strainer is specified
A strainer line gives size, class, type, end connection, body material and screen — mesh or perforation size and screen material — for example "4 in class 150 Y strainer, RF flanged, A216 WCB, SS316 screen 40 mesh". Y strainers suit lower debris loads and can be installed horizontally or in downward vertical flow; basket strainers hold more debris and are used ahead of pumps and meters; duplex basket strainers allow one basket to be cleaned while the other stays in service. Temporary cone strainers are fitted between flanges during commissioning and removed afterwards.
How a flame arrestor is specified
A flame arrestor is selected by its application (end-of-line on a vent, or in-line within a pipe), the type of flame it must stop (deflagration or detonation), the explosion group of the gas (IIA, IIB or IIC), the operating temperature and the flow capacity — for example "6 in class 150 end-of-line flame arrestor, group IIA, for a hydrocarbon storage tank vent". Flame arrestors are tested and certified to ISO 16852, and are frequently combined with a pressure-vacuum relief valve on atmospheric storage tanks.
Documentation and supply terms
- Mill test certificate
- EN 10204 3.1 certificate for every line, traceable to the heat number marked on the item. EN 10204 3.2 with third-party witness on request.
- Marking
- Material grade, size, rating and heat number marked on each item to the governing standard (MSS SP-25 for valves, flanges and fittings).
- Inspection
- Positive material identification, dimensional checks and third-party inspection arranged where the project specifies them.
- Sour and low-temperature service
- NACE MR0175 / ISO 15156 hardness limits and impact testing applied where the piping class calls for them, and stated on the certificate.
- Quotation
- Each line states the standard, grade, origin, lead time and certification before you commit. Listing does not indicate stock held by CRS PLUS.
Frequently asked questions
What is a flame arrestor?
A flame arrestor is a device with a metal element of narrow passages that absorbs heat from a flame front and extinguishes it, while allowing gas to flow. It prevents an external ignition travelling back into a tank or a flammable process system.
What is the difference between a deflagration and a detonation flame arrestor?
A deflagration arrestor stops a subsonic flame, typical at a vent opening or close to the ignition source. A detonation arrestor is built to stop a supersonic, high-pressure flame front that can develop in long pipe runs. The installation position and pipe length decide which is required.
What does gas group IIA, IIB or IIC mean?
It classifies gases by how easily a flame passes through narrow gaps. Group IIA includes most hydrocarbons such as propane and gasoline vapour; IIB includes ethylene; IIC includes hydrogen and acetylene. The arrestor must be certified for the group of the gas it protects.
Y strainer or basket strainer?
A Y strainer is compact and suits clean fluids and steam with low debris loading. A basket strainer has a larger screen area and debris capacity and is preferred on pump suctions and liquid lines where cleaning frequency matters.
What documentation comes with these items?
Material certificates for pressure-containing parts and pressure test certificates; for flame arrestors, the ISO 16852 type-test certificate and marking showing gas group and application.
Request a strainer or flame arrestor quotation
A structured offer follows within 72 hours.
Manufacturer and brand names, where mentioned, are used for identification only. CRS PLUS sources these products through its qualified supplier base and holds no distributor, reseller or agency appointment from any manufacturer.