Chat with us, powered by LiveChat
Filter by Brands

Marlin Wafer Check Valves


What is a Wafer Check Valve? 

A Wafer Check Valve is a general-purpose or high-performance check valve, with a short face-to-face design. Unlike swing check valves, the Wafer Check Valve is typically flangeless but is also made in a retainer less lug design, or double flanged retainer less design. Marlin is now owned by Crane Energy. The Marlin catalog is viewable on Authorized Parts, Inc. website. See:


Marlin Wafer Check Valve Types

Commonly known as dual disc check valves, or duo-chek valves, universal features of wafer check valves are that they are spring-loaded and operate equally well in horizontal or vertical positions. Spring tension can be customized to accommodate low, minimum, standard, or high torque springs. Additionally, seating surfaces can be specified to meet service demands. Valves manufactured by Marlin Valve Company, Houston, Texas conform to API 594, API 598, API 6D, API 6A, and ANSI B16.34 specifications.

The most basic Marlin Wafer Check Valve is Style M. The Style M valve is Cast Iron body, Aluminum Bronze spring-loaded double, with Buna-N seat and it mates between 125# and 150# flanges. It is suitable for frequent cycling of flow, but not for solids or slurries. The size range is from 2” to 72” diameters.

Beyond the Style M, is Style MP retainer less, Style ML lugged retainer less, Style MLP double-flanged retainer less, and Style ME extended body. All styles of Marlin Wafer Check Valves are assembled with different material combinations, depending upon the service conditions. Body materials in Alloy 20, Cast Iron, Ductile Iron, WCB Cast Steel, 316 Stainless Steel, Bronze, Monel, Hastelloy C, WC6 Chrome-Moly alloy steel, Duplex stainless steel, and low-temperature LCB.  Seat material options are metal-to-metal seats, Buna-N, Viton, Teflon, Neoprene, EPDM, and Hypalon, for bubble-tight seating. Spring material options are Inconel 600, Inconel x-750, 316 stainless steel, or Monel. Request a material recommendation based on the service media. 

High-performance valve bodies are cast in finishes of a flat face, raised face, ring joint, or butt weld end in Pressure classes 125, 150, 175 UL/FM, 250, 300, 600, 900, 1500, and 2500 in pipe sizes 2” thru 88”. 


What is a Retainerless Wafer Check Valve Design? 

For critical applications, Style MP retainer less, Style ML lugged retainer less, and Style MLP double-flanged retainer less Duo-Chek valves feature a one-piece body with no pin retainer

penetration through the body. The internal design is the same as the Style M Duo-Chek valve but offers no leak path due to the unique retainer-less feature. Special service valves for hazardous or lethal service applications are most suitable for the retainer less design to prevent a possible leak through the valve body into the atmosphere. The design utilizes a one-piece body without pipe plugs, pin retainers, or outside bolting.


Typical applications for Marlin retainer less valves are Bleaching Lines, Black Liquor, Chemical Recovery, Chlorine Service, Aromatics, Acids, and Caustics. 


Marlin Wafer Check Valve Replacement Parts

Parts for Marlin Valves can be quoted if the valve size is specified, the figure number, and serial number. Submit an RFQ with a list of parts that may include the Valve Body, Plates, Stop Pins, Hinge Pin, Springs, Pin Insert, Snap Ring, Body Bearing, Plate Bearing, and Spring Bearing. 

Use Authorized Parts RFQ form at:

How to Order Marlin Wafer Check Valves

Marlin Wafer Check Valves employ a smart Figure Number System that allows for custom combinations of sizes and materials, or existing popular Figure Numbers. The first designation specifies Size, then Design Style, Pressure Class, Body & Plate material, Seat or Seal selection, Spring Alloy, and End Connection. 


For example: 18M300CSPSR = 18” Style M, Class 300, CS Body, SS Plates, SS Spring, Raised Face

See the figure number system at


Specify the valve size and figure number if possible. Include the serial number if available, then submit a list of parts: Valve Body, Plates, Stop Pins, Hinge Pin, Springs, Pin Insert, Snap Ring, Body Bearing, Plate Bearing, and Spring Bearing can normally be supplied.

Yes. Other manufacturer’s valves cross-reference to Marlin Valves. Stockham Valve, Gulf 

Valve Company, Davis Valve Company, Mission Valve Company, Crane Valve Company, Goodwin Valve Company and Crane Duo-Chek are examples of manufacturers with equivalent products. However, not all design features are the same, so care should be taken when evaluating. Be especially careful when reviewing the face-to-face dimensions when making comparisons.

Yes. All valve testing requirements can be made available for Rockwell Valves, including  MTR’s, NDE , Pressure Testing, Radiography Testing, Magnetic Particle, Dye Penetrant, PMI, Positive Material Identification, Hardness Testing, and Failure Analysis, including a Certificate of Compliance, if requested.

Scroll to Top