Check valve applicable occasions

The purpose of using the check valve is to prevent the reverse flow of the medium, and the check valve is generally installed at the outlet of the pump. In addition, check valves should also be installed at the outlet of the compressor. In short, in order to prevent media counterflow, check valves should be installed on equipment, devices or pipelines.

Generally, vertical lift check valves are used on horizontal pipes with nominal diameter of 50mm. Straight-through lift check valves can be installed on both horizontal and vertical lines. The bottom valve is generally only installed on the vertical pipe at the pump inlet, and the medium flows from bottom to bottom.

Swing check valves can be made of very high working pressure, PN up to 42MPa, and DN can also be very large, up to 2000mm or more. Depending on the material of the shell and seal, it can be applied to any working medium and any working temperature range. The medium is water, steam, gas, corrosive media, oil, food, medicine, etc. The operating temperature of the medium is between -196 and 800℃.

Swing check valves can be installed in an unlimited position and are usually installed in horizontal pipelines, but can also be installed in vertical pipelines or inclined pipelines.

The application of butterfly check valve is low pressure and large diameter, and the installation occasion is limited. Because the working pressure of the butterfly check valve can not be very high, but the nominal diameter can be very large, can reach more than 2000mm, but the nominal pressure is below 6.4MPa. The butterfly check valve can be made into a clamp type, which is generally installed between the two flanges of the pipeline and adopts the form of a clamp connection.
The butterfly check valve can be installed in an unlimited position and can be installed in a horizontal pipe, a vertical pipe or a inclined pipe.

Diaphragm check valve is suitable for the pipeline prone to water shock, the diaphragm can be very good to eliminate the water shock generated when the medium countercurrent. Because the working temperature and use pressure of the diaphragm check valve are limited by the diaphragm material, they are generally used in low-pressure normal temperature pipelines, especially for water pipes. The general working temperature of the medium is between -20 and 120 ° C, and the working pressure is less than 1.6MPa, but the diaphragm check valve can achieve a larger caliber, and the maximum DN can be more than 2000mm.

Diaphragm check valve is widely used in recent years because of its excellent waterproof performance, simple structure and low manufacturing cost.

Because the sealing parts of the spherical check valve are rubber coated spheres, it has good sealing performance, reliable operation and good water shock resistance. And because the seal can be a single ball, but also can be made into multiple balls,
so it can be made into large caliber. However, its seal is a rubber coated hollow sphere, which is not suitable for high pressure pipelines, only suitable for medium and low pressure pipelines.

Because the shell material of the spherical check valve can be made of stainless steel, and the hollow sphere of the seal can be covered with polytetrafluoroethylene engineering plastic, it can also be applied in the pipeline of general corrosive media.

The operating temperature of this type of check valve is between -101 and 150℃, its nominal pressure is less than 4.0MPa, and the nominal diameter range is between 200 and 1200mm