Stop check valves are self-automated valves and they do not require any external control or human intervention, instead it relies completely on the flow of liquid to open and close.

These valves typically have two openings, one for media to enter in the valve and other for the liquid to leave. In simple words, stop check valves allow a media to flow only in one direction and prevents fluid to flow in opposite direction. These valves are basically used everywhere, including household uses and in every industry. Like other types of valves, Check type valves can be used with different types of fluids like air, gases, liquid etc.
The check valves are manufactured to open at very low differential pressure, allow fluent flow conditions and are very easy to disassemble for service and inspection. The (MSCA) stop check valve is embedded with vented cap and also has internal back-seating enabling the spindle seal to replace the valve still under pressure. Laser cut V-ports ensure excellent opening and closing characteristics to check valves (check valve (MCHV) 50-125/ Stop check valve (MSCA)). The Maniks check valve cone has built-in flexibility to provide a tight and precise closing towards the valve seat.
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Check Valve Feature:
1) Applicable to HFC, HCFC, R717 (Ammonia) and R744 (CO2).
2) Can be used in all chemical as well as petro-chemical applications.
3) Easy and Fast valve overhaul service. It is easy to replace the top part and no welding is needed.
4) Designed to open at a very low differential pressure of 0.04 bar (0.58 psig).
5) Designed with built-in damping chamber which prevents valve flutter, in case of lower refrigerant velocity and/or low level density.
6) Easy to disassemble for service and inspection.
7) Internal back seating of the valve enables replacement of the spindle seal when the valve is active (under pressure).
8) Optimal flow characteristics that provides quick opening to completely open position.
9) Protection against pulsation by built-in damping facility.
10) Housing and bonnet material is low temperature steel according to requirements of the Pressure Equipment Directive and other international classification authorities.
11) Temperature range: –60/+150°C (–76/+302°F)
12) Each valve is clearly marked with type, size and performance range.
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Check Valve Installation:
The check valve must be mounted vertically with the cone downwards. The valve is designed to resist very high internal pressure. However, the piping system in general should be designed to avoid liquid traps and reduce the risk of hydraulic pressure caused by thermal expansion.
For further information about check valves refer to installation instructions for MSCHV-X/ MSCA-X. If cold refrigeration oil having low viscosity enters and settles in the damping chamber, problems with the check valve may arise. Consequently, it may be necessary to modify the valve for more viscous liquids by enlarging the hole to the damping chamber.

Technical Data for Check Valves:

• Refrigerants: Applicable to HCFC, HFC, R744 (CO2) and R717 (Ammonia). For further details refer to product instruction for MSCHV-X/ MSCA-X.
• It looks same as a globe valve on the outside, however, it is essentially a lift check valve provides with a manual control to regulate continuous opening and closing, and to be completely stopped. These valves are basically applied in power plants, in applications like steam generator, starter water, boiler circulation, turbine cooling, boiler feed water, and safety systems.
Why Maniks Stop Check Valves?
Maniks
Stop check valves are like having two valves in one 1) as a globe type valve, they isolate or regulate flow the flow of liquid and 2) stop check valve can be modified as a check valve, to prevent reverse flow. They provide a comparatively efficient and economic solution where regulation, isolation and prevention of backflow of fluid are required as performance characteristics for a piping system.