Double-tile-back structured brake shoe and manufacturing process thereof

Abstract

The invention discloses a double-tile-back structured brake shoe and a manufacturing process thereof, and belongs to the technical field of brakes. The double-tile-back structured brake shoe comprises tile backs, stoppers, brake shoe noses, steel backs, friction bodies and a welding line b, wherein the stoppers are welded at the two ends of the outer arc surfaces of the tile backs; the brake shoe noses are positioned in middle of the outer arc surfaces of the tile backs to form tile back components; the steel backs and the friction bodies are sintered to obtain brake block components; secondary tile backs are arranged between the tile back components and the brake block components; the tile back components and the brake block components are fixedly connected with the outer arc surfaces and the inner arc surfaces of the secondary tile backs; the adjacent end surfaces of the steel backs of all the brake block components are contacted in a gapless manner; and such steps as pressing of the friction bodies, sintering of the brake blocks and welding of the tile back components are used for machining. As the secondary tile backs are arranged between the tile back components and the brake block components, the thickness of the tile backs is increased, the bending deformation resistance of the tile backs is improved, the serviced life of the brake shoe is prolonged, and effects of preventing the looseness or the falling of the brake blocks and eliminating the potential safety hazards of vehicle driving and braking are achieved.

Description

technical field [0001] The invention belongs to the technical field of brakes, and relates to a brake shoe on a rail transit brake block, in particular to a double-back structure brake shoe and a manufacturing process thereof. Background technique [0002] Brake shoe is an important part that produces braking torque when the friction surface of brake shoe is pressed against the wheel tread under the action of brake thrust when railway locomotives and vehicles are braking. In the existing powder metallurgy brake shoe, the friction body 5 and the steel back 4 are sintered to form an integral brake block, and then the brake block is welded to the inner arc surface of the tile back 1 at equal intervals. [0003] Due to the limitation of the design of the friction area of ​​the brake block, and the length of the brake shoe must meet the requirements of relevant standards, the length of the friction body 5 cannot be too small. When welding the brake pads, since the three brake pa...

AI Technical Summary

Problems solved by technology

When welding the brake pads, since the three brake pads are equidistantly arranged on the inner arc of the tile back 1, the distance between the brake pad friction body 5 in the middle and the brake pad friction bodies 5 on the left and right sides is narrow, When welding, the welding rod or nozzle cannot be inserted into the gap between the two brake blocks to weld the steel back side between the two brake blocks and the brake shoe back 1, so when welding the middle brake block, only the brake block can be welded against the tile On both sides of the side of the back 1, the edge between the two brake blocks is not welded, so that the welding seams of the three brake blocks on the back 1 of the tile are disconnected and not continuous, such as figure 1 shown

[0004] Manual welding or automatic welding is usually used for brake block welding. Manual welding requires higher personal skills of the operator, while automatic welding needs to pause in the middle, sometimes there will be 8 virtual welds in the weld, and even cause the middle brake block and tile back The welding depth and thickness of 1 is small, resulting in low welding strength. During frequent braking, the tile back 1 is deformed by force, and the tile back 1 returns to its original shape after the brake is released. Horizontal cracks appear in the welds 8 on both sides of the block, and gradually expand, which will eventually cause the brake block in the middle to fall off, causing the brake shoe to fail; at the same time, because the tile back 1 between the two brake blocks has the smallest thickness and is the weakest, it is subjected to bending stress Stress concentration is easy to occur when the tile back 1 is deformed. As the number of deformations of the tile back 1 increases, cracks are prone to appear on both sides of the tile back 1 between the two brake blocks, and gradually extend to the inner side of the tile back 1 until the tile back 1 breaks, causing the brake shoe to fail. ; The above two failure modes will affect the driving safety of the vehicle and bring great safety hazards to driving

[0005] Since there is a through hole for welding the brake shoe nose 3 on the outer arc surface of the tile back 1, and the size of the through hole is limited by the plate thickness of the brake shoe nose 3 and the width of the brake shoe nose 3, if the original tile back 1 is directly added The material thickness of the thick tile back 1 will not be conducive to the punching and forming of the through hole for welding the brake shoe nose 3 on the tile back 1, and the later machining method will increase the production cost of the tile back 1 and reduce the overall production efficiency of the brake shoe

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