Rail transit industry helps machine tool industry development

In 2011, China's rail transit has completed eight accelerations, and the track transit has undergone a rapid development. Take Shanghai to Nanjing as an example. Before the speed increase, it takes 4 to 5 hours. The fastest time is only 1 hour, and the speed has exceeded 350 kilometers per hour. It takes only 5 hours from Shanghai to Beijing.

In 2012, SCI Verkehr, a well-known consulting firm in Germany, published a research report that announced the top ten in the world of rail transit equipment manufacturer's new manufacturing in 2010, and China's CSR ranks first in the world. CSR Qishuyan Locomotive Co., Ltd. is a modern large-scale enterprise that produces main-rail railway diesel locomotives as its main products. The main models include Dongfeng 8, Dongfeng 8B, Dongfeng 11, Dongfeng 11G and HXN5 series diesel locomotives.

The locomotives for the first six times of China's railway speed increase are mainly DF11G diesel locomotives, which are mainly based on CSR vehicles. In the past two years, the speed of railways has been dominated by electric locomotives. However, diesel locomotives still have an irreplaceable position, especially in speeding freight locomotives. From the overall perspective, the demand for diesel locomotives is still quite large. There are currently more than 19,000 diesel locomotives in the whole country. In addition, large-capacity locomotive locomotives are currently in short supply in major locomotives, coal mines, and petroleum companies. According to preliminary estimates, the total number of locomotives to be updated every year is more than 600 (not Including about a few thousand repair vehicles each year).

A brief explanation of the processing difficulty of main parts of rail transit involves rail transit machining. The main parts that are relatively difficult to machine are the bogie sections of bogies and air-core axle bushes, and the key components of diesel engines. Locomotive diesel engine main parts have complex structure, manufacturing precision, shape and position tolerances and surface roughness requirements (the accuracy index is mostly in the 5 to 7 grade, roughness Ra0.4 or so), requiring good interchangeability, such as the body, the crankshaft The main purpose of the connecting rod and cylinder head is to ensure that the locomotive has good reliability, high durability and high safety factor in high-speed operation.

In terms of diesel engine key components, the relative dimensional accuracy of many components is in the μm class, which was previously unimaginable and cannot be achieved at all.