Mechanical processing method of axle bridge for rail vehicle

Abstract

The invention relates to a mechanical processing method of an axle bridge for a rail vehicle. The method comprises the following steps: (1) treating the bottom surface of an axle bridge blank as a positioning surface, and clamping; drilling central holes in the end surfaces of two shaft necks; (2) ejecting ejector pins into the central holes in the shaft necks; roughly turning the outer circumferences of the rotating shaft necks; roughly milling the bottom surface of each mounting seat and the bottom surface of each shaft head, and drilling holes in the bottom surfaces; roughly milling the top parts of the shaft heads and the upper end of each mounting seat; (3) modifying the central holes in the two ends of the shaft necks after stress-relieving treatment; (4) positioning and clamping in central holes in the two ends of a semi-finished axle bridge through the ejector pins on a machine tool; performing fine turning for outer circles of the shaft necks; performing fine milling for the planes of the bottom parts of the mounting seats, and reaming; (5) clamping the semi-finished axle bridge on the mounting seats of the machine tool; driving two coaxial grinding cutting tools to rotate through an output shaft of the machine tool so as to enable an empty chamber of a forward-moving barrel-shaped tool body to gradually sleeve the corresponding shaft neck; cutting the outer circle of each shaft neck through a blade until the specified size is reached, so as to obtain the finished axle bridge. With the adoption of the method, the axle bridge processing precision can be improved, and the processing efficiency and product qualification ratio can be improved.

Description

technical field [0001] The invention relates to a machining method for a rail vehicle axle bridge, which belongs to the technical field of rail transportation. Background technique [0002] New modern low-floor rail vehicles require the use of axle and bridge components in order to lower the vehicle floor to around 350 mm. As an important part of the bogie of a low-floor vehicle, the axle bridge supports the weight of the entire car body. The independent wheels connected at both ends of the axle bridge rotate independently under the drive of the motor to drive the vehicle. In order to ensure the safety and comfort of vehicle operation, there are high requirements on the structural performance of the axle bridge and the assembly accuracy with the independent wheels. See figure 1 The shaft bridge 1 (or called a bent shaft) with an integrated structure as shown includes a shaft body, a shaft head 1-2 arranged vertically at both ends of the shaft body, and a shaft journal 1-1 ...

AI Technical Summary

Problems solved by technology

Due to the irregular shape of the shaft bridge structure, it is difficult to process

Especially when rough turning, finishing turning and grinding are used to process the journal of the axle bridge, since the axle bridge is a large crankshaft part, the center of gravity is not on the center line of the journal, and the journals on both sides of the axle bridge When turning and grinding, it is necessary to rotate the shaft and bridge, so it is easy to generate a large centrifugal force, resulting in poor machining accuracy of the journal surface, and the coaxiality does not meet the requirements

Although most of the centrifugal force can be offset by the counterweight method, it is difficult to grasp the size and position of the counterweight due to the irregular structure of the axle bridge. The machining allowance is large, not only the tool consumption is large, especially the grinding amount usually needs to exceed 1mm, which reduces the processing efficiency

However, a large machining allowance cannot solve the influence of centrifugal force on machining accuracy, and the eccentric rotation will cause large deviations in the size and shape and position tolerances of the machined products, which makes the qualified rate of machined products not high.

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