SCREW FASTENING METHOD, MANUFACTURING METHOD FOR WHEEL AND ITS SHAFT FOR RAILROAD, AND WHEEL AND ITS SHAFT FOR RAILROAD

摘要

PROBLEM TO BE SOLVED: To suppress a drop in the fastening thrust force even in the case where a thermal expansion and contraction are applied by fastening a member to be fastened having a greater coefficient of thermal expansion than the fastening member by means of driving a screw. SOLUTION: One to five pieces of initially coned disc spring washer are installed on at least either of the seat faces of a bolt and nut, wherein the stress generated in the inside surface lower part is equal to or below the allowable value in the relationship between the stress generated in the inside surface lower part of the washer when it is compressed and the plate thickness of the washer, and the total thickness generates the required deflection in the relation between the deflection of the washer and the plate thickness of the washer. This requires the use of a smaller number of washers for generating the same deflection amount, and the stress generated in the inside surface lower part owing to a thermal expansion is lessened, and it is possible to suppress the drop in the mounting thrust force likely to be caused by a thermal expansion or contraction. COPYRIGHT: (C)2004,JPO