Air separation plant maintenance

According to a DEAR air separation user, during the operation of a set of air separation plant that has been in operation for 5 years, it is found that under the condition that the inlet guide vane does not change, the expansion air volume of the expander gradually decreases, and the rotation speed of the expander gradually decreases, the outlet pressure of the booster end of the expander rises from 0.76MPa to 0.8MPa, the inlet temperature rises from - 110 ° C to - 95 ° C, and the working condition of the chilled water pump is poor.

There must be enough smooth straight pipe sections before and after the flow orifice plate. The distance is 10 times of pipe diameter in front of the orifice plate and 5 times of the pipe diameter behind the orifice plate, and no factors affecting the measurement accuracy (such as pipe joint, etc.) are allowed. The inner surface of the pipe weld should also be ground smooth, and the gasket should not extend into the inner diameter of the pipe. And carefully check the installation direction of the orifice plate, do not install it in reverse. (judgment method: the small exit is the entrance, and the large exit is the outlet)