Method for monitoring wearing capacity of shaft housing of submerged roller

The invention discloses a method for monitoring wearing capacity of a shaft housing of a submerged roller. By the method, a grate arranged above a coating boiler is provided with a displacement sensor for detecting the horizontal position of some a point of band steel, then a signal is converted into a measured value D of the horizontal displacement value of a measured point of the band steel through a displacement changing and transmitting device, then the measured value D of the horizontal displacement value is transmitted to a computer system, and finally the computer system outputs the measured value D of the horizontal displacement value in real time and compares the measured value D of the horizontal displacement value with a set value in the computer system, the set value is a theoretical value y of the horizontal displacement value of the measured point of the band steel, the theoretical value corresponds to some a value of the wearing capacity A of the shaft housing, and when the horizontal displacem