Check Valve Selection Guide

The following are key criteria and factors to consider when selecting check valves to ensure their proper application in a variety of piping and equipment:
Prevention of backflow: To ensure that the medium does not flow backwards, check valves must be installed on equipment, devices and pipelines.
Media suitability: check valves are usually suitable for clean media, and is not recommended for media containing solid particles or high viscosity.
Vertical lift check valve application: in the nominal diameter of up to 50 mm horizontal pipeline, it is recommended to choose vertical lift check valve.
Flexibility of straight-through lift check valves: this type of check valve can be installed on both horizontal and vertical pipelines.
Choice of pump inlet: for the pump inlet piping, the bottom valve is a good choice, it is usually installed only on the vertical piping of the pump inlet, and to ensure that the medium flows from the bottom up.
Comparison of lift and swing type: Lift check valve performs better in terms of sealing, but the fluid resistance is larger. Horizontal type should be installed on horizontal pipeline, while vertical type is suitable for vertical pipeline. The installation position of swing check valve is relatively flexible, and it can be installed on horizontal, vertical or inclined pipelines.
Wide range of applications for swing check valves: these check valves can withstand very high working pressures (up to 42MPa) and can be made in very large sizes (maximum diameter of more than 2,000mm). They are suitable for a wide range of media and operating temperature ranges.
Selection for specific applications: For low-pressure, large-diameter and restricted installation space, special attention needs to be paid to the selection of suitable check valves.
Flexibility of butterfly check valves: butterfly check valves can be installed on pipelines in any direction, including horizontal, vertical or inclined.
Specific application of diaphragm check valve: this type of check valve is especially suitable for pipelines prone to water shock, it can effectively eliminate the water shock generated when the medium backflow. It is usually used for low-pressure normal temperature pipelines, especially water pipelines.
The applicability of ball check valve: ball check valve is suitable for low-pressure pipeline, and can be made into a large diameter. Its shell can be made of stainless steel, and the seals can be wrapped with PTFE engineering plastics, so it is also suitable for corrosive media.
Selection of incompressible fluids: in the selection of check valves for incompressible fluids, the first to assess the required closing speed, and then select the type of check valve to meet this requirement.
Selection of compressible fluids: For compressible fluids, the selection of check valves is similar to that for incompressible fluids. If the media flow category is very large, can use the check valve with speed reduction device. If the media flow frequent rapid stop and start (such as compressor outlet), then it is recommended to use lift check valve.
Determine the size of the check valve: The valve supplier must provide information data on the selected size in order to find the appropriate size of the valve when fully open at a given flow rate.
Selection for different diameters and pressures:
For high and medium pressure check valves up to DN50 mm, it is recommended to select vertical lift check valves and straight-through lift check valves.
For low pressure check valves below DN50 mm, butterfly check valves, vertical lift check valves and diaphragm check valves are good choices.
For high and medium pressure check valves with DN greater than 50 mm and less than 600 mm, swing check valves are the recommended choice.
For low and medium pressure check valves with DN greater than 200 mm and less than 1200 mm, non-wearing ball check valves are a good choice.
For low pressure check valves with DN greater than 50 mm and less than 2000 mm, butterfly check valves and diaphragm check valves are good choices.
Reduced water shock: For pipelines that require less or no water shock when closing, slow-closing swing check valves and slow-closing butterfly check valves are ideal.
We hope this guide will help you better understand and select the right check valve for your needs.