After assembling the hub of the pump on the shaft, the verticality and concentricity of the hub and the shaft should be carefully checked. Generally, two dial indicators are arranged on the end surface and the outer circumference of the hub. When the disk drive rotates the shaft, the value of the full run-up (including the end runout and the radial runout) of the hub is observed to determine the perpendicularity between the hub and the shaft and the coaxiality Degree of the situation. Different speeds of the coupling requirements of full beating different, different types of coupling requirements for full beating also vary, but after the assembly of the hub in the shaft, you must make the hub full runout deviation in the Within the design tolerances, this is one of the major quality requirements for coupling assembly.
Submersible pump assembly caused by the wheel full run-out value does not meet the requirements for many reasons, first of all may occur in the manufacturing process due to the error for the field assembly, mainly due to improper handling of the hub hole surface modification, the hub and shaft concentric Degree of deviation. Another reason is that when a keyed shaft coupling is assembled, the hub and the shaft are not coaxial due to incorrect key assembly. The correct installation of the key should make both sides of the key and the keyway closely fit the wall, usually with the paint color inspection assembly, with the bad file can be used to repair the file or blade to meet the requirements. The upper part of the key generally gap, about 0.1-0.2mm or so. High-speed rotating machinery requires high concentricity between the hub and the shaft. High concentricity can not be obtained by a single-key connection. Concentricity can be improved by using a double-key connection or a spline connection.