The piston rod is a key part of the refrigeration compressor, and its parallelism and surface strength are very high. For example, a certain piston rod has a diameter of 63.5 mm and a length of 630 mm, and the cylindricity is specified as φ0.018 mm. The surface of the cylinder is specified to be abrasion resistant, and the strength of the surface is specified to be ≥50HRC. Generally, high-frequency quenching is used to solve the processing technology.
The following editor introduces the straightening method for the slight deformation of the piston rod.
1. Use 2 pieces of V-shaped iron to support both sides of the piston rod, and rotate the piston rod with the dial indicator on the inner diameter of the middle frame, record the shaking value of the piston rod, and mark the high and bottom points on the rod.
2. Use the pin and anchor bolt to press down the height by 5 to 11mm, keep it still, and hit the shaft with a copper rod several times to stabilize the stress. The strength of the copper rod is 130-160HB, and the strength of the piston rod is 280-300HB. Because the copper rod is softer than the piston rod, the surface of the piston rod is not easily deformed when hit.
3. Remove the pin and check the vibration of the piston rod again according to Figure 1. If the vibration exceeds the standard, it can be adjusted again until it reaches the standard. Good care and work experience are required during the period.
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