5、 With the development of air separation units to super large scale, the requirements for the diameter of GLOBE valves will be very large. Generally, GLOBE valves with a diameter greater than DN250 are difficult to find in the market, and the price will be much higher. If the butterfly valve is selected, the adjustment performance will be relatively poor, and the small opening cannot be adjusted. Therefore, it is considered to use two pipelines and two valves in parallel at this time. The advantage of this use is that the coordinated control of the two valves has a better light adjustment when the opening is small. At the initial stage of equipment start-up, use one valve for adjustment; Under normal working conditions, one valve is fully opened and regulated by the other valve.

The working medium and applicable conditions of the compensator meet the relevant specifications and rules
The connection mode is flange connection, and the flange shall meet the requirements of process piping specification. The pneumatic butterfly valve of compensator shall have a bright appearance without oxidation
The main alloy components of stainless steel for compensator are FE, CR, NI, MN, TI, SI, etc. Within the annealing temperature range, the oxidation of FE and NI is not the main problem, but the oxidation range of CR, MN, SI, TI is precisely within the heating temperature range. It is the oxidation of these alloy elements that affects the external brightness of stainless steel. Especially, the oxidation of chromium removes chromium from the surface of stainless steel, which will reduce the corrosion resistance of stainless steel, When the CR content is about 17% and the TI content is 0,5%, the dew point of H2 must be lower than - 60 ℃ to prevent CR. The bright and continuous solution treatment process of oxidized metal compensator hose in the heating range of 800-1150 ℃ for TI is stopped under the H2 maintenance atmosphere, and only the gas purity meets the requirements, After H2 restoration, the stainless steel metal surface can be completely restored to a bright, oxidation free metal surface How to obtain a satisfactory compensator Metallographic structure compensator
In order to obtain satisfactory metallographic structure, the bright continuous solution treatment furnace needs to set three cooling stages and be able to stop conditioning independently. Another key problem is to request that the temperature of each part should ensure the average difference. The muffle type bright continuous solution treatment furnace is to stop heating from the outside of the muffle tube on an average basis, so that the pneumatic butterfly valve compensator is heated on an average when passing by, In order to ensure the average organization of the pneumatic butterfly valve along the moving direction, the linear speed of the pneumatic butterfly valve in the heating furnace should be kept constant. According to the inherent characteristics of different data, the cooling speed can be effectively controlled through the control of the cooling phase of the pneumatic butterfly valve bright solution treatment furnace, so that a satisfactory metallographic tissue compensator bright solution treatment principle compensator can be obtained
Bright heat treatment is the heat treatment process in which the workpiece is not oxidized at all during the heat treatment process, and the surface adheres to bright heat treatment. The workpiece in the solution treatment room is heated to the appropriate temperature and kept warm, so that the surplus phase is fully dissolved, and then rapidly cooled to obtain supersaturated solid solution. The typical heat treatment process of austenitic stainless steel enables solution treatment. When the workpiece is heated to 1050 ℃, Properly hold one end of the heat for a time so that all carbides are dissolved in austenite, and then rapidly cool to below 350 ℃ to obtain supersaturated solid solution, that is, the average unidirectional austenite structure. The key of this heat treatment process is rapid cooling. The cooling speed is required to reach 55 ℃ per second, and the carbides quickly pass through the precipitation temperature zone after solution. The holding time should be as short as possible, Otherwise, it is easy to show coarse grains, affecting the performance and surface brightness. Austenitic stainless steel will show black oxide skin if air enters the surface during heating and insulation. In order to ensure the brightness of the substrate, nitrogen and hydrogen synthesized from ammonia are used as the maintenance atmosphere in the furnace of the heat treatment furnace. Nitrogen is a neutral gas and will not be oxidized during high temperature maintenance, Analysis of bright solution treatment process for flexible pipe of bright metal compensator without decarburization