150 Technical Questions And Answers About Pumps To Help You Fully Understand Pumps

121.455 How to install a radial ball bearing on a shaft if the knocking method is used?

Answer: Use a steel sleeve, copper sleeve or copper rod to knock the bearing ring symmetrically and evenly into the designated position. It is forbidden to knock the outer ring of the bearing to avoid damaging the bearing. After installation, check that the outer ring of the bearing should be flexible and free to rotate without blocking.

122. What are the common methods for disassembling rolling bearings?

Answer: Knocking method, pulling method, pushing method, and thermal disassembly method.

123. What should be paid attention to when using the knocking method and pulling method to disassemble rolling bearings (bearings on the shaft)?

Answer: 1) The knocking force should generally act on the inner ring of the bearing, and should not be knocked on the rolling element and the cage, and knocking on the outer ring of the bearing is not allowed. 2) When using the pull-out method, the inner ring of the bearing should be pulled, and the outer ring of the bearing should not be pulled only to avoid excessive loosening or damage to the bearing.

124. How should the dial indicator be installed when the clearance of the sliding bearing is measured by the lifting shaft method?

Answer: Install the bearing, do not tighten the bolts, set a dial gauge on the upper bearing back, set a dial gauge on the shaft diameter, gently lift the shaft but not too high, until the upper bearing back dial gauge pointer moves.

125. What are the assembly requirements for split radial sliding bearings, bearing caps, and bearing seats?

Answer: During assembly, the bearing back should be in good contact with the cap and seat hole. The contact area should not be less than 40%-50% of the entire area, and no gaps are allowed. Otherwise, it will need to be repaired. The fixed pins and screws that fix the sliding bearing should have their ends buried 1-2mm in the bearing body. The various gaskets should be the same as the shape of the bearing mouth surface, and their width should be less than 1mm on the inner side of the bearing. The gaskets should be flat and free of thorns, and the thickness of the gaskets on both sides of the bearing mouth should be consistent.

126. How to adjust the clearance of split radial sliding bearings?

Answer: 1) Adjust the gaskets at the joint surface so that the top clearance and side clearance of the shaft and bearing meet the requirements. In the absence of regulations, based on experience, one thousandth to two thousandths of the journal can be taken, and it should be selected within this range according to the speed, load and lubrication conditions.

2) The side clearance is generally one-half of the top clearance.

3) If the structure does not allow the addition of gaskets, the clearance must be adjusted by grinding the upper bearing shell. While grinding the adjustment clearance of the shell shell, it is also necessary to ensure that the lower and upper shell shells should fit tightly and should not exceed 0.05mm.

127. What are the main forms of rolling bearing damage?

Answer: 1) fatigue pitting, 2) abrasion, 3) burns, 4) electrolytic corrosion, 5) cage damage, 6) inner and outer ring fracture, 7) ball out of roundness, 8) raceway surface peeling.

128. What are the characteristics of key connection?

Answer: Relying on the side of the key to transmit torque, the parts on the shaft are only fixed circumferentially, and cannot withstand axial force. If axial fixation is required, fastening screws or locating rings and other positioning parts are required.

129. What are the assembly requirements for loose key connection?

Answer: For ordinary flat keys, semicircular keys and guide keys, after assembly, there should be some interference on both sides of the key, a certain gap should be left on the top surface of the key, and the bottom surface of the key should contact the bottom surface of the shaft groove. For the sliding key, the side key contacts the bottom surface of the wheel groove, while there is a gap between the key and the bottom surface of the shaft groove.

130. What are the steps for preparing a loose key connection?

Answer: 1) Clean the burrs on the key and keyway. 2) File the key length, and there should be a gap of about 0.1mm between the key head and the shaft groove. 3) Use the key head and keyway for trial matching. For ordinary flat keys, flat round keys and guide keys, the key can be embedded in the shaft groove only, while the sliding key should be embedded in the wheel groove. 4) Add engine oil to the mating surface, and install the key on the shaft with a copper rod or a soft cushion of a hand hammer.