Stainless steel tube for brake system of rail vehicle and method for producing same

Abstract

The invention provides a stainless steel tube for a brake system of a rail vehicle and a method for producing the same. The stainless steel tube comprises the following components in weight percentage: less than 0.030 percent of C, more than 0 percent or less than 1.00 percent of Si, more than 0 percent or less than 1.50 percent of Mn, less than 0.40 percent of P, less than 0.015 percent of S, 10.5 to 12.50 percent of Cr, 0.30 to 1.00 percent of Ni, less than 0.030 percent of N, more than 0 percent or less than 0.10 percent of Cu, 6*(C+N) to 0.75 percent of Ti and Nb, and the balance of Fe and inevitable impurities. The method for producing the stainless steel tube comprises the following steps of: smelting, continuous casting, hot rolling, punching or extruding, and deep processing of the steel tube; the method is characterized in that molten iron is made into molten steel according to the components of the stainless steel tube; at the hot rolling step, the start-rolling temperature is between 1,080 and 1,150 DEG C, and the end-rolling temperature is between 850 and 900 DEG C; and the punching or extruding deformation temperature is controlled to be between 850 and 1,100 DEG C. The stainless steel tube produced by the method has the advantages of good corrosion resistance, good welding, mechanical and cold processing properties, and low price.

Description

technical field [0001] The invention relates to a stainless steel pipe for a railway vehicle braking system and a manufacturing method thereof, in particular to a stainless steel pipe for a railway passenger car braking system and a manufacturing method thereof. Background technique [0002] Now, in the braking system of railway vehicles, seamless steel pipes are used for pneumatic / hydraulic pressure transmission of braking force to provide safe and reliable braking and transmit large braking force. Seamless steel tubes made of low carbon steel are usually used in brake systems. Due to the relatively large differences in the operating environment of railway vehicles, the temperature, temperature, salt, corrosive gas and pressure experienced by the same vehicle in a short period of time are affected by factors such as, and these factors vary greatly. During long-term use, these factors have caused corrosion to the brake system exposed to the air. Corrosion products or valve ...

AI Technical Summary

Problems solved by technology

During long-term use, these factors have caused corrosion to the brake system exposed to the air. Corrosion products or valve rust cause brake failure, valve blockage or brake power drop, which become hidden dangers of the brake system, reducing the risk of damage to the brake system. Service life of the brake system, increased maintenance work and repair costs

In recent years, the "stainless steel pipe for liquid transportation" made of 1Cr18Ni9Ti in GB / T14976 has been widely used in the braking system of railway freight cars, gradually replacing Q235, and better solving the problems and hidden dangers existing in the use of Q235. The price of Ni continues to rise, and the price of 1Cr18Ni9Ti stainless steel pipes is also rising, which greatly increases the cost of purchased parts in the railway wagon manufacturing industry

For the braking system of railway passenger cars, since the connection between steel pipe and steel pipe, steel pipe and valve is threaded connection, this connection method is different from the welding connection method used in the railway freight car brake system, especially the thread processing of 1Cr18Ni9Ti steel pipe is difficult. The processed brake system has the defects of non-standard thread type and poor air tightness. Up to now, 1Cr18Ni9Ti steel pipe has not been widely used in the brake system of passenger cars. Therefore, imported carbon steel welded steel pipes with internal and external phosphating treatment are used to make the brake system of passenger cars. , this kind of steel pipe is not only expensive, but also brings high procurement and maintenance costs to the railway passenger car manufacturing industry

[0003] Since the performance of Q235 steel cannot meet the requirements, and the thread processing of 1Cr18Ni9Ti steel pipe is difficult and expensive, it is necessary to invent a stainless steel pipe with good performance and low price for the braking system of railway vehicles