Cast Flow Retainerless Dual Plate Check Valve
The Cast Flow retainerless dual plate check valve is designed without external shaft retention penetrations in the body, minimizing potential leakage paths to atmosphere. This construction is specified for oil & gas, steam, and process vapor applications where fugitive emissions must be controlled. Discs open via differential pressure and close with springs; no actuator is required.
Technical Data
- Retainerless series range: DN50–DN600
- Available types: wafer, flanged, solid lugged
- Materials: ductile iron, carbon steel, stainless steel, superduplex, aluminium bronze
- Design standards: EN 14341 / EN 12516, API 594 / ASME B16.34
- Face-to-face: EN 558 series 16 or API 594
- Connections: PN6 to PN100 and ANSI 125# to 600#, depending on configuration
- Testing: EN 12266 / ISO 5208 or API 598
- Minimum backpressure for tightness: 0.3–0.5 bar
Seat and Internal Materials
Standard configurations include discs in EN-GJS-400-15 or WCB, shafts in AISI 304, springs in AISI 302, and Buna-N / NBR seats. For demanding services, options include stainless, duplex, bronze-aluminium, AISI 316 or Inconel springs, and seats in EPDM, Viton, Neoprene, Klingerit, or metal-to-metal.
Applications
Suitable for pump stations, potable water distribution, fire protection, low-pressure air compressors, oil & gas, steam, and process vapor lines. Material selection is based on pressure, temperature, corrosion, and seat leakage requirements.
Selection Considerations
DN selection should be based on flow rate, pressure drop, flow velocity, and minimum backpressure. For seawater or brine, PREN, chloride content, and temperature must be evaluated for duplex or superduplex selection.
FAQ
When is a retainerless body specified? When project specifications require elimination of external shaft or bolt leakage paths.
Is it the same as a standard dual plate? No. While operation is similar, internal retention is achieved without external body penetrations.
Description
Certificates
CHECK VALVES MANUFACTURER
WATER TECHNOLOGIES – IN HOUSE MANUFACTURING
CASTFLOW VALVES S.L., is formed by technicians that have been developing valves for many years.
Counting on this experience we created new patterns for castings, including the improvements that
have been necessary to obtain a longer durability and better hydraulic features.
CASTFLOW VALVES S.L. is a ISO 9001:2015
ISO 14001:2015 – ANNEX III MODULE H approved company for design and production.
We produce valves based on our own design and we can offer to our clients all
TECHNICAL SUPPORT related to our valves.
We require maximum quality on prime materials. The foundries we work with, are highly specialised in
materials and posses a very important knowledge in casting our products. Our department for investigation and development is orientated to the technical requests of
our customers, adapting our development to these requests. The structure of CASTFLOW VALVES S.L.is oriented to serve our customers technical requests.
ISO 9001:2015
ISO 14001:2015
ANNEX III MODULE H

- CERTIFICATE OF THE QUALITY ASSURANCE SYSTEM EUROPEAN DIRECTIVE 2014/68/EU
- ISO 14001:2015
- ISO 9001:2015
Quality assurance plans
PROVIDING HIGH QUALITY PRODUCTS
Based on the customers requirements CASTFLOW VALVES S.L. can proceed with testing methods
according to a quality assurance plan and test and inspection schedules.
Receiving inspection
In process Control
Non destructive testing
US-testing-magetic
particle-dye
penetrant tests Porotest Dk30
Output control
pressure test of each valve
output documents
termination control
marking and packaging control
