Another point is the material of flue check valve. The materials of flue check valves sold in the market are mainly plastic or metal.
Among them, plastic check valves can be divided into many kinds, and the order of materials from poor to good is PE, PP, ABS and PC. The best is PC, but its manufacturing cost and raw material price are relatively high. ABS materials are mostly used in the industry, with high strength and good toughness.
It is not recommended that you buy a metal check valve, because the metal check valve is limited by the process and has no sealing rubber gasket. The baffle is heavy, the flue smokes upwards, and the wind resistance is large. The sealing surface of the baffle is large, which is easy to stick when it is greasy and needs to be cleaned frequently.
So I suggest you start with the plastic check valve made of ABS or PC. You can buy it on Taobao or Tmall, and the price ranges from tens to one hundred, mainly depending on the materials and workmanship.
Extended data
Check valve installation should pay attention to the following items:
1, don't let the check valve bear the weight in the pipeline. Large check valves should be supported independently to avoid being affected by the pressure generated by the pipeline system.
2. Pay attention to the flow direction of the medium during installation, which should be consistent with the direction of the arrow on the valve body.
3. The lifting vertical flap check valve shall be installed on the vertical pipeline.
4. The lifting horizontal disc check valve shall be installed on the horizontal pipeline.
Refer to Baidu Encyclopedia-Flue Check Valve