4. Hard seal pneumatic ball valve shall be used as far as possible for pneumatic cut-off valve
The lower the leakage of the emergency cut-off valve, the higher the leakage. The leakage of the soft sealing valve is the least. The actual disconnection effect may be good, but it is not abrasion resistant and has poor credibility. Seen from the double standards of small leakage and reliable sealing, soft sealing disconnection is not better than hard sealing disconnection. For example, the multi-functional ultra light regulating valve has high reliability and high leakage rate of 10-7, which can already meet the requirements of emergency cut-off valve.

The baffle plate is corrosion resistant, wear-resistant, and has the function of guiding and maintaining the thermal insulation layer. In order to make the non-metallic contraction joint can reach the application effect in the pipeline, its various mechanical properties can really play a role, and extend its service life, please install the device according to the following requirements:
1. When non-metallic contraction joints are installed in the pipeline, they should be kept in a natural state as far as possible. Do not artificially deform the product during installation, so as to prevent early damage of the product and weakening of the application effect.
2. When the non-metallic contraction joint is connected with the flange, the screw rod of the bolt shall extend to the outside of the flange to avoid the scratch of the thread tip on the rubber (fabric) sphere of the joint during the contraction deformation. The bolts on each flange end face shall be evenly pressurized and tightened one by one. It is required that the tightness of all bolts can be different as far as possible. In places with poor application conditions, spring washers can be added in addition to flat pads, To prevent the nut from loosening.
3. There is a support frame in the middle of the joint. The support frame should be kept in place before the device. After the bolts are tightened, all of them should be knocked off to ensure that the device is reasonable and that its physical and mechanical properties really play a role.