Freight car compartment powder metallurgy brake block

Abstract

The invention relates to a powder metallurgy brake block for a boxcar, composed of a brake shoe back (4) and a shoe block (3) which are connected with each other, wherein, the brake shoe back (4) adopts the material of QT400-18 and is shaped by casting once; the shoe block and the brake shoe back adopt the connection structure of welding or riveting; a powder metallurgy friction block (6) on the shoe block (3) adopts powder metallurgy friction materials, takes iron as matrix, is added with lead, graphite, supramoly, copper and aluminium sesquioxide and so on, all of which are mixed uniformly pro rata, and is formed by chill pressing and compression sintering. The invention is characterized by reliable structure, stable drag friction performance, low surface temperature rise, small relative dispersion and good wearing resistance, etc., and is suited to starting or towing a car on a railway with speed at or below 160km / h.

Description

technical field [0001] The invention relates to a brake shoe for a railway vehicle, in particular to a powder metallurgy brake shoe for a carriage of a freight car. Background technique [0002] With the continuous development of the railway science and technology industry, the operating speed of railway trains is constantly increasing, and railway freight cars are developing in the direction of speed-up and heavy load. Therefore, the requirements for braking performance of brake shoes are also getting higher and higher. Not only brake shoes are required to have good Braking performance, and it is required that the brake shoes do not cause abnormal wear and damage to the wheel tread, no material transfer during braking, no harmful substances, and no pollution to the environment. [0003] At present, the braking materials of railway freight cars are mostly high-phosphorus cast iron tiles and synthetic brake shoes. During the operation of railway freight cars after the speed i...

AI Technical Summary

Problems solved by technology

[0003] At present, the braking materials of railway freight cars are mostly high-phosphorus cast iron tiles and synthetic brake shoes. During the operation of railway freight cars after the speed is increased, their defects are gradually exposed. For example, the temperature of the friction surface of cast iron tiles increases during use. , the friction coefficient decreases, resulting in extended braking distance, because the cast iron tile has a large specific gravity and hardness and directly brakes on the train wheel, it is easy to cause damage to the wheel tread; and the synthetic brake shoe is easy to cause damage to the wheel tread due to poor heat dissipation. Scratches or even surface peeling, changes in the metallographic structure of the wheel

At the same time, the friction coefficient of the above two brake shoes is also very unstable in rainy and snowy weather conditions, and the friction coefficient decreases sharply during braking, which leads to a significant extension of the braking distance

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