Routine maintenance and maintenance during grease injection of all welded pneumatic ball valve Professional maintenance of all welded pneumatic ball valve before and after production before welding plays a vital role in the normal production and operation of the valve. Correct, orderly and effective maintenance will protect the valve, make the valve function normally and extend the service life of the valve. Daily grease injection maintenance is an important routine maintenance link, and there are often neglected aspects in the work.

Reliability of PTFE compensator and application of contraction joint
The reliability of compensator is composed of design, manufacturing, device and operation management. Reliability should also stop thinking from these aspects. For the selection of materials for bellows used in heat supply network, in addition to the working medium, working temperature and external environment, the possibility of stress corrosion, the impact of water treatment agent and pipeline cleaning agent on the materials should also be considered. On this basis, the welding and forming of bellows materials, as well as the performance cost ratio of the materials should be separated to select the economic and applicable bellows manufacturing materials. Under normal conditions, the data of bellows selection shall meet the following conditions
(1) High elastic limit, tensile strength and fatigue strength ensure normal operation of bellows.
(2) Good plasticity, convenient for processing and forming of bellows, and sufficient hardness and strength can be obtained through subsequent treatment processes (cold work hardening, heat treatment, etc.).
(3) Good corrosion resistance, meeting the working requirements of bellows in different environments.
(4) Good welding performance, meeting the welding process requirements of bellows in the manufacturing process. For the heat pipe network laid in the trench, when the pipeline where the compensator is located is in a low terrain, the corrugated pipe will be soaked by rainwater or accidental sewage. Therefore, the data with stronger corrosion resistance, such as iron nickel alloy and high nickel alloy, should be considered. Due to the high price of such materials, the PTFE compensator can only add a layer of corrosion resistant alloy on the surface contacting with corrosive media when manufacturing bellows. The fatigue life design can be seen from the failure type and cause analysis of the bellows compensator that the planar stability, circumferential stability and corrosion resistance of the bellows are related to its displacement, i.e. fatigue life. Low fatigue life will cause the stability and corrosion resistance of metal bellows to decline. 1. Product characteristics:
Compensator thermal shrinkage: non-metallic shrinkage can provide larger multi-dimensional compensation in a smaller size range.
Compensating device error: because system error is unavoidable in pipeline connection, non-metallic compensator can better eliminate device error.
No reverse thrust: as the main material is fiber fabric, the transmission is weak, and the use of non-metallic compensator can simplify the design.
High temperature and corrosion resistance: Fluoroplastics and organosilicon materials used have good performance of high temperature and corrosion resistance.
Sound attenuation and vibration isolation: fiber fabrics and insulation cotton can absorb sound and isolate vibration transmission, which can effectively reduce the noise and vibration of boiler, fan and other systems. Good sealing performance: the PTFE compensator has good sealing performance under the action of various media.
Low price: 1/2~1/3 of imported similar products.
The device is easy to maintain.
2、 Other service items:
According to the user's special request (corrosion resistance and high temperature resistance), we can design and manufacture various specifications of non-metallic contraction joint products and other products, repair or replace various damaged and invalid non-metallic contraction joints for users (including the replacement and maintenance of imported non-metallic contraction joint parts), and provide free non-metallic contraction joint selection of engineering piping and on-site device technical guidance.
3、 Scope of application
1. Boiler factory; 2. Cement plant; 3. Iron and steel plants, melting furnaces, combustion furnaces; 4. Thermal power plants and nuclear power plants; 5. Air conditioning air supply system; 6. Glass and mineral wool industry; 7. Petrochemical enterprises; 8. Air and gas cleaner; 9. Fan factory, and all in the industry with high flexibility and sensitivity to pressure and request, must be equipped with the center of the compensator contraction joint.
4、 Main technical parameters:
Pressure: vacuum~0.1MPa
Temperature: - 20 ℃~1000 ℃
Round: DN50~DN5000
Rectangles: arbitrary sections