- Swing Check Valves: Valve disc is provided with anti-rotations pin. Full opening swing check valves to API 6D or API 6A suitable for pig passage are also available.
- Piston Check Valves: Normally up to sizes 2à, (larger sizes are also available) both T-Pattern and Y-Pattern are available.
- Dual Plate Check Valves: Valves provided with double disc and spring. They are available with metal to metal seats and soft seats. This design reduces substantially the weight of the valve as well as the face to face dimension.
- Tilting Disc Check Valves: When the check valve must be operated by a very small pressure drop this design is used. Valve disc is balanced in such a way that very small variations of pressure open/close the valve. This reduces substantially the pressure drop across the valve.
- Emergency Assisted Check Valves: Used in the turbine steam extractions of power plants. Valve is provided with a pneumatic piston and solenoid valve in such a way that when a closing signal is received in the solenoid valve the air in the pneumatic piston is released starting the closing stroke of valve disc and ensuring fast valve closing by fluid-media.
- Testable Check Valves: In those cases when indication of check valve position is required the valve is provided with a position indicator and limit switches. Also an operating lever is available in case proper rotation of hinge shaft must be checked.
- Butterfly Check Valves: Normally used in the outlet of large size pumps or inlet of hydro power plant turbines. Valve can operate like a butterfly valve but also like a check valve by fluid-media.
The Ringo Check Valves are offered in various versions to meet the application specifications. These Ringo Check Valve versions include swing check valves, piston check valves, dual plate check valves, butterfly check valves, emergency assisted check valves, testable check valves, and tilting disc check valves.
Check valves are designed to meet requirements of ANSI B16.34, BS-1868, ANSI B16.5, ANSI B16.10, API 602, API 6D and/or API 6A. For nuclear service ASME III, AD-Mekblatter and RCC-M are available. These control valves can be equipped with SAMSON GROUP actuators, manual operators, and valve accessories.