Positive action of valve positioner: when the input current signal increases, the air pressure output to the diaphragm head increases;

Due to different application purposes, the expansion joints of non-metallic contraction joints can be locally made of different materials, usually rubber fabric. When non-metallic contraction joints are used in high temperature environment, their expansion joints generally use silicone rubber. Because the molecular structure of silicone rubber determines that it has high thermal stability, its temperature resistance is much better than other types of rubber except fluororubber, and the price is not expensive. It is widely used in different fields in China; Therefore, it is more appropriate to use silicone rubber tape in non-metallic expansion joints of cold air ducts with hot air as the medium.
The flue gas environment of the power plant contains a large amount of acidic substances such as SO2, SO3, HCl and HF, and the performance of silicone rubber drops rapidly under the action of a small amount of acidic substances. Even if the anti-corrosion coating is set inside, leakage is likely to occur during operation, leading to a rapid decline in the performance of expansion joints, and the products will be damaged quickly. Therefore, it is not appropriate to select silicone rubber for non-metallic expansion joints in the flue.
We use fluororubber tape in non-metallic expansion joints with flue as the medium. Fluoroelastomer is a kind of synthetic polymer elastomer containing fluorine atoms on the carbon atoms of the main chain or side chain. It has the characteristics of high temperature resistance, oil resistance and corrosion resistance of various chemicals.
Fluoroelastomer can work at 200 ℃ for a long time, which is the rubber material with the best corrosion resistance. The acid gas contained in the flue gas of the power plant is almost non corrosive to the Fluoroelaster. Therefore, Fluoroelaster is the preferred material for expansion joints in non-metallic contraction joints in the flue gas environment of the power plant. Although the price is a little expensive, it ensures the quality, which seems appropriate and necessary in the long run.
Pressure bearing single wave body and multi wave body compensators play an irreplaceable role in some special working conditions. The electronic weighing scale used in the desulfurization and powder injection system of a steel plant was originally used to compensate equipment and pipelines with metal compensators. Due to the large reverse thrust, the electronic weighing scale was not accurately debugged and could not return to zero and weigh correctly. This kind of compensator with rectangular diameter and large displacement can only reach the application request by using non-metallic data. Through special structural design and data design, the working condition requirements are met.