Check valve installation position instructions

1. check valve is also known as a check valve or check valve, its role is to prevent the backflow of media in the pipeline.

2.the bottom valve of the pump suction pipe also belongs to the check valve category. Check valve according to the structure, can be divided into lift check valve, swing check valve and butterfly check valve three.

3. lift check valve can be divided into vertical and horizontal two. Swing check valve is divided into single valve, double valve and multi-flap type. Butterfly check valve for straight-through, the above types of check valve in the form of connection can be divided into threaded connection, flange connection and welding three. The opening and closing parts rely on media flow and force to open or close the valve to prevent the backflow of media called check valve. Check valve belongs to the automatic valve category, mainly used for one-way flow of the medium on the pipeline, allowing the medium to flow in one direction only, in order to prevent accidents.  
Pump valve network experts say, check valve (Check Valve): according to the structure, can be divided into lift check valve, swing check valve and butterfly check valve three. Lift check valve can be divided into vertical and straight two.
Swing check valve is divided into single valve, double valve and multi-flap type. Butterfly check valve for the disc type double valve, disc type single valve, the above check valve in the form of connection can be divided into threaded connection, flange connection, welding and butt-weld connection four kinds.  
Check valve is also known as a one-way valve or check valve, its role is to prevent the backflow of media in the pipeline. Water pump suction bottom valve also belongs to the check valve category.  
    

4.the opening and closing parts rely on the media flow and force to open or close, to prevent the backflow of media valves called check valves. Check valve belongs to the automatic valve category, mainly used for one-way flow of media on the pipeline, only allow the media to flow in one direction to prevent accidents.

Check valve selection:     

    1.check valve is generally suitable for clean media, should not be used for containing solid particles and viscosity of the larger media.
     

    2.for DN50mm low-pressure check valve, it is appropriate to use butterfly check valve, vertical lift check valve and diaphragm check valve; for DN greater than 200mm, less than 1200mm low-pressure check valve, it is appropriate to use non-abrasive ball check valve; for DN greater than 50mm, less than 2000mm low-pressure check valve, it is appropriate to use butterfly check valve and diaphragm check valve.
    

    3.diaphragm check valve is suitable for easy to produce water on the pipeline, diaphragm can be very good to eliminate the water generated by the media backflow, but subject to temperature and pressure restrictions, generally used in low-pressure room temperature pipeline.                        For the requirement to close when the water impact is relatively small or no water pipeline, it is appropriate to use slow-closing swing check valve and slow-closing butterfly check valve.    

    4.for the pump inlet pipeline, it is appropriate to use bottom valve, bottom valve is generally installed only in the pump inlet vertical pipeline, and the media flow from the bottom up.   
  

    5.lift type than swing type sealing, fluid resistance, horizontal should be installed in the horizontal pipeline, vertical installed in the vertical pipeline.     

    6.swing check valve installation location is not restricted, it can be installed in the horizontal, vertical or inclined pipeline, such as installed in the vertical pipeline, the media flow direction from the bottom up.  
   

    7.swing check valve should not be made into a small diameter valve, can be made into a very high working pressure, nominal pressure can reach 42MPa, and nominal diameter can also be very large, the maximum can reach more than 2000mm. According to the shell and seal materials can be applied to any working medium and any working temperature range. The medium is water, steam, gas, corrosive medium, oil, medicine, etc. The medium working temperature range is between -196--800℃.     

Construction and installation of check valve:

    1.installation location, height, import and export direction must meet the design requirements, pay attention to the direction of media flow should be consistent with the direction of the arrow marked on the valve body, the connection should be solid and tight;
      

    2.the valve must be installed before the appearance of inspection, the valve nameplate should comply with the current national standard "General Valve Marking" GB 12220 provisions. For working pressure greater than 1.0 MPa and in the main pipe to play a cutting role in the valve, the strength and tightness test should be conducted before installation, qualified before use. Strength test, the test pressure for the nominal pressure of 1.5 times the duration of not less than 5min, the valve shell, packing should be no leakage for qualified. Tightness test, the test pressure of 1.1 times the nominal pressure; test duration in accordance with the requirements of GB 50243;
     

    3. in the pipeline do not make the check valve to bear the weight, large check valve should be independently supported so that it is not affected by the pressure generated by the pipe system.

The installation of check valves note top:

    1. in the pipeline do not make the check valve to bear the weight, large check valve should be independently supported, so that it is not affected by the pressure generated by the pipe system.    
  

    2. the installation of the direction of media flow should be consistent with the direction of the arrow in the valve body ticket.     

    3. lift type vertical flap check valve should be installed in the vertical pipeline.     

    4. lift type horizontal flap check valve should be installed in the horizontal pipeline.  In short, check valve in the selection and installation process, to pay attention to the above issues, to avoid unnecessary losses caused by human error.