Mechanical seal friction torque of the testing technology is currently the main support reaction force method and delivery method.
 Support reaction force method is based on power machinery under the action of the torque reaction force generated by the change to measure the friction torque. The advantage is no rotating parts to stationary parts stored in the signal transmission problems, and determine the bearing reaction force method is simple and easy to implement. EMayer, Li Kun and other support reaction force method using the mechanical seal face friction torque was measured. In the sealed chamber can be set on the rotating rod force, and make it act on the force sensor, which measured torque. However, the sealed chamber will affect the rotation friction bearing precision, so the rotating support demanding, Li Kun use of aerostatic bearings.
 Transfer method is based on when the elastic element in the transmission of torque generated by the change of physical parameters to measure the torque. Measuring torque transfer method uses small, lightweight instruments, torque sensors can be directly connected in series to the transmission system, without changing the mechanical system structure. JASilvaggo, Song Pengyun, Zhao Zengshun other in the spindle motor and the seal is installed between the torque sensor to measure shaft torque, the torque measured by subtracting the no-load running torque of the main bearings and rotating components of friction in a medium mixing Torque can be obtained by mechanical seal friction torque. However, the method is not direct, and due to run during normal operation and when the load is not the same conditions, leading to possible large deviation results, accuracy is more difficult to ensure.
 Accurate measurement of in-service mechanical seal friction torque, is conducive to the improvement of working life of mechanical seals and the leak rate control. However, normal operation, smaller mechanical seal face friction torque sensor output was smaller, and in particular the high parameters (high-speed, high pressure, high temperature), the mechanical seal face friction torque signal is often measured even during the other signals Are overwhelmed by interference. Thus the actual conditions, it is difficult or by turning the seal chamber and seal the motor shaft torque sensor installed between the mechanical seal faces to test the friction torque. To avoid the consumption of power equipment and the main bearing friction torque of the mechanical seal Measurement of friction torque, Sun Jianjun, etc. in the ring after a set of static torque sensors, to improve the measurement accuracy.