Traction Frame and Lifter Unit: mm Serial No. Action 1 Adjustment 2 Adjustment 20-139 Items to be inspected Judgment Wear of traction ball hinge joint Standard Dimension Tolerance Standard Clearance Clearance Limit Axle Hole 120 -0.120 -0.297 +0.180 0 0.120 0.447 - Clearance between gear ring and traction frame Standard Clearance Clearance Limit 1.5 1.0-2.0