Dual Plate Check Valve
The name describes the internals: two plates, hinged at the centre and held closed by a spring, sitting in a short wafer body. The plates open with forward flow and close together when flow reverses.
The same wafer-style, spring-assisted, soft-seated valve answers both terms buyers use: a dual plate check valve manufacturer datasheet and a double door check valve manufacturer purchase order are quoted against one DN40–DN600, PN16 (0–16 bar) build, API 598 tested.
Buyers often meet both terms on the same enquiry. In this range they describe the same wafer-style, spring-assisted, soft-seated two-plate check valve — so a datasheet written for "dual plate" and a purchase order printed as "double door" can be quoted against one product.
The name describes the internals: two plates, hinged at the centre and held closed by a spring, sitting in a short wafer body. The plates open with forward flow and close together when flow reverses.
The same construction described from the outside. The two plates are also called "doors", so a double door valve is a dual plate valve — identical in function, sizing and application.
Some older catalogue text for single-disc or swing check valves describes a valve with a single moving part that swings clear of the flow path. That description belongs to a different valve type. The PN16 double door valve supplied here is built around two plates with spring assistance, which is why the body can stay short and the seat can stay soft.
Two plates, spring assisted, wafer body, short face-to-face, soft seat. Suits tight pipe runs and fast closure duties such as pump discharge protection.
One disc swinging on a hinge, usually in a longer body with higher flow resistance. Often specified where the line layout already allows the extra face-to-face length.
Valve sourcing decisions usually come down to paperwork that matches the pipe spec, a design basis that inspectors accept, and a supplier that answers a technical question with a document. These are the standards behind the double door check valve PN16 range.
API 609, ASME B16.34 and ASME Section VIII form the stated design basis, so the valve can be reviewed against the same codes as the rest of the line.
ASME/ANSI Class 125LB & 150LB, EN/DIN PN6–16, BS 10 Table D/E, AS 2129 Table D/E and JIS 5K / 10K (JIS B2220) flange standards are supported for cross-market projects.
Dimensions follow API 609, ISO 5752, EN 558-1, ASME B16.10 and MSS SP-68, which helps the valve drop into an existing pipe gap during a retrofit.
Pressure testing is carried out to API 598, with EN 12266-1, ISO 5208 and BS 6755-1 listed as the testing and inspection standards for the range.
The valve is offered with an ISO 9001 quality management system and CE marking under the PED, giving purchasing teams a documented route to conformity.
Check valves, butterfly valves and related pipeline products sit under one factory contact, so a project package can be quoted with consistent documentation.
The PN16 double door check valve is the reference configuration for this page: wafer connected, spring assisted, soft seated, and built for water, oil and air lines across the DN40 to DN600 size range.
The short face-to-face dimension lets the valve sit between flanges where a longer body will not fit, and the two plates leave very little obstruction for the media to pass. Spring assistance improves dynamic response, so the plates close faster when flow reverses instead of waiting for backflow to build.
| Connection | Wafer type |
| Size range | DN40 – DN600 (1 1/2 in – 24 in) |
| Pressure rating | PN16 · 0 – 16 bar (0 – 1.6 MPa) |
| Media | Water / oil / air |
| Medium temperature | −25 °C to 180 °C |
| Testing pressure | Shell 1.5 × rated; seat 1.1 × rated, acc. to API 598 |
| Design basis | API 609, ASME B16.34, ASME Section VIII |
| Face-to-face | API 609, ISO 5752, EN 558-1, ASME B16.10, MSS SP-68 |
See the full specification for the Double Door Check Valve PN16 →
Body, disc, stem and seat are selected as a set rather than one at a time: the body carries the pressure rating, the disc handles the flow and wear, and the seat compound decides how the valve seals in your media.
| Component | Material options |
|---|---|
| Body | Ductile iron; carbon steel (WCB, WCC); low-temperature carbon steel (LCB, LCC, LC1) |
| Disc | Ductile iron; SS304; SS316; Duplex 2205; Super Duplex 2507; aluminum bronze |
| Stem | SS420; SS304; SS316; 17-4PH (SS630); Duplex 2205; Super Duplex 2507 |
| Seat | EPDM; HTEPDM; NBR (Buna-N); SIL (VMQ); FKM (VITON™); HYPALON™ |
| Coating | Epoxy resin, 200 µm – 250 µm |
Rated pressure spans 0 – 16 bar (0 – 1.6 MPa) across the DN40 – DN600 range, with a medium temperature window of −25 °C to 180 °C for water, oil and air service.
Six seat compounds are offered, and the seat is the component that sits against the medium. Confirm the compound against your fluid, cleaning regime and operating temperature before the body material is fixed.
Every unit follows the same route from material selection to inspection release, with the pressure test values fixed by API 598 rather than set per order.
Body, disc, stem and seat are picked to the requested specification before castings enter the line.
Seat faces and flange interfaces are machined to the face-to-face and flange standard on the drawing.
Plates, spring and seat are fitted into the wafer body, then the assembly is set for the specified size.
Shell and seat tests are carried out at the API 598 multipliers listed in the table below.
Test results and inspection records are prepared, then the valve is packed for dispatch.
| Test / standard | Requirement |
|---|---|
| Shell test (API 598) | 1.5 × rated pressure |
| Seat test (API 598) | 1.1 × rated pressure |
| Testing & inspection standards | API 598; EN 12266-1; ISO 5208; BS 6755-1 |
| Design basis | API 609; ASME B16.34; ASME Section VIII |
| Face-to-face conformity | API 609; ISO 5752; EN 558-1; ASME B16.10; MSS SP-68 |
Find the line you are working on below, check the product fact that decides the configuration, then act on the buyer decision before the enquiry goes out.
Distributors, importers and project buyers can take the double door check valve under their own brand and their own documentation set. Each point below is a customisation the factory can discuss against your specification.
Your brand on the body marking and nameplate, with tag numbers aligned to the project valve list.
Match the line standard across ASME/ANSI Class 125LB & 150LB, EN/DIN PN6–16, BS 10 Table D/E, AS 2129 Table D/E and JIS 5K / 10K, at a pressure rating up to PN16.
Pressure test records to API 598 and inspection documents prepared to match the submittal requirements of your project.
Export packing and order scheduling are agreed per project — send your size list and delivery windows so MOQ and lead time can be confirmed against the final configuration.
Send the line data and the factory will come back with the matching double door check valve configuration, material set and test documentation.
Size (DN40 – DN600), rated pressure within 0 – 16 bar, flange standard and required quantity.
Water, oil or air, plus continuous and peak temperature within the −25 °C to 180 °C range.
Body, disc, stem and seat are proposed together with testing to API 598 and the documents you require.
Keep adjacent product options together for a faster catalog comparison.
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View productyes. both names describe the same wafer-style check valve, which uses two spring-assisted plates — also called doors — instead of one swinging disc.
the pn16 valve covers dn40 to dn600 (1 1/2 in to 24 in) at a rated pressure of 0 to 16 bar (0 to 1.6 mpa). flange standards include asme/ansi class 125lb & 150lb, en/din pn6–16, bs 10 table d/e, as 2129 table d/e and jis 5k / 10k.
bodies are offered in ductile iron, wcb/wcc carbon steel and low-temperature carbon steel (lcb, lcc, lc1). discs can be ductile iron, ss304, ss316, duplex 2205, super duplex 2507 or aluminum bronze, with stems in ss420, ss304, ss316, 17-4ph, duplex 2205 or super duplex 2507, and seats in epdm, htepdm, nbr, sil, fkm or hypalon™. body coating is epoxy resin at 200 – 250 µm.
testing follows api 598: a shell test at 1.5 × rated pressure and a seat test at 1.1 × rated pressure. en 12266-1, iso 5208 and bs 6755-1 are also listed as testing and inspection standards for the range.
the valve is specified for water, oil and air service with a medium temperature range of −25 °c to 180 °c. confirm your continuous and peak temperatures, and the seat compound, before ordering.
send the line size, pressure rating, flange standard, media and temperature through the contact page. oem and project requests can cover private label marking, nameplate details, packaging and documentation.
