1, the pump violent vibration or noise: Reason: pump installation is not strong or the pump is installed too high; motor ball bearings damaged; pump spindle bending or spindle with the motor is not heart, not parallel and so on. Treatment: install a steady pump or reduce the installation height of the pump; replace the motor ball bearings; correct the bending of the pump shaft or adjust the relative position of the pump and the motor. 2, drive shaft or motor bearing overheating: the causes: the lack of oil or bearing rupture. Approach: add oil or replace the bearing. Valve import pump industrial washing machine 3, the pump is not water: causes: pump and suction pipe did not fill the diversion; moving water level lower than the pump drainage pipe; suction pipe rupture. The sealing surface between the screw and the housing is a curved surface. There are unsealed areas such as ab or de on this surface and a number of triangular notches abc, def with the groove portion of the screw. The notches of these triangles form a passage for the liquid, allowing the drive screw groove A to communicate with the grooves B, C in the driven screw. The grooves B, C, along with their spiral around the back, respectively, and the back of the grooves D, E communicated. Since there are also triangular notches a'b'c 'similar to the front face on the sealing surfaces where the grooves D, E engage with the groove F (which belongs to the other thread), D, F, E will also communicate. In this way, the groove ABCDEA also form a "∞" -shaped sealing space (such as the use of single-head thread, the groove will be along the axial disk Rao screw, the suction port through, can not form a seal). Not hard to imagine, in such a screw, will form a number of independent "∞" -shaped sealed space, each sealed space occupies the axial length exactly equal to the lead of the tired rod t. Therefore, in order to make the suction and discharge of the screw, the length of the screw thread should be longer than one lead.