The inspection of crankshaft mainly includes the inspection of crack, deformation and wear.
(1) Repair of cracks. After the crankshaft is cleaned, it should first be checked for cracks. The crack can be inspected by magnetic flaw detector or dye penetrant. If the crankshaft is inspected for cracks, it should generally be scrapped and replaced.
(2) Maintenance of crankshaft bending. The common axis of the spindle neck at both ends should be used as the basis to check the radial circular runout error of the middle spindle neck. During the test, the crankshaft spindle necks at both ends are placed on the V-shaped block of the test plate, the dial indicator contacts are vertically placed on the middle spindle neck, and the crankshaft is slowly turned one circle. If the maximum swing difference shown by the dial indicator pointer, that is, the radial circular runout error value of the middle spindle neck, is greater than 0.15mm, the pressure should be corrected. Below this limit, it can be corrected in conjunction with the grinding spindle neck.
(3) Maintenance of crankshaft distortion. The test of crankshaft distortion is to turn the connecting rod journal to the horizontal position, and use the dial indicator to determine the height difference between the two journals on the same orientation. This height difference is the amount of distortion.
(4) Maintenance of crankshaft journal wear. For the crankshaft that is allowed to be repaired after inspection, it is necessary to check the wear amount of the journal: first check the journal for wear marks and damage, and then measure the roundness error and cylindricity error of the spindle journal and connecting rod journal. The roundness error is the main test for the wear of the short crankshaft journal, and the roundness and cylindricity error must be tested for the long crankshaft journal.
fold