Introduction of P65/R65 steel rails
GOST R 51685 is the state standard of the Russian Federation for railway steel rails.This standard is effective for railway rails,used for joined and continuous welded rail tracks of railways and for production of point switches.There are four type of train rails with the steel grades of M76T,K76T,M76,K76 produced according to this standard,they are P50/R50,P65/R65,P65K,P75.Among them,P65 is widely used in railroad construction projects.Baotou Steel is an experienced train rail manufacturer who can produce P65 steel rails in large quantity.
P65 steel rail section diagram
Advantages of Baotou Steel on – line heat treatment train rail
At present, Baotou Steel has two world advanced 100-meter universal rolling production lines, with a total design capacity of 2.1 million tons a year. It is one of the main manufacturers of steel rails in China.The steel rails produced by Baotou Steel have been exported to many countries such as Canada, the United States, Mexico, Brazil, Argentina, Uruguay, Bolivia, South Korea, Indonesia, Malaysia, Thailand, the Philippines, Bangladesh, Saudi Arabia, Pakistan, Iran, Kenya, Australia, Spain, Angola, Mongolia, Laos, north Korea, Vietnam and other countries.
China’s domestic online heat treatment rail manufacturers mainly adopt the online water mist cooling process and the online pure air cooling process.The stability of water mist cooling process is poor, the adjustment of process is difficult, the structure stability of rail is difficult to control, the performance index is low, which affects the comprehensive service life of rail.In view of the limitations of the on-line water mist cooling process, Baotou Steel has optimized and upgraded the 100-meter rail waste heat quenching production line, and realized the on-line pure air cooling process of rail through length. This process has high recognition in the industry and good process stability, which can effectively guarantee the safety of rail organization and greatly improve the internal performance index of rail.
Comparison of GOST R 51685 76T steel rail and TB/T 2344 U75V steel rail
With optimization and upgrading, the TB/T 2344 standard H340 U75V online heat treatment rail structure and performance indexes produced by Baotou Steel have reached the industry’s advanced level, as follows:
|Main performance index of U75V online heat treatment rail|
|Tensile properties||Surface hardness HBW||The section hardness HRC|
|Tensile strength Mpa||Elongation %||Test number||Average number||Volatility number||First||Last|
|Our actual production||1250-1300||11-14||355-380||≥355||0-8||37-42||35-40|
|Chemical Composition of TB/T 2344 U75V and GOST R 51685 76T|
|TB2344||U75V H340||0.71-0.8||0.5-0.8||0.75-1.05||≤0.03||≤0.025||—||0.04-0.12||≤0.01||0.007- 0.025|
|Range of dimensional deviation|
|Types||Gost R 51685 P65 rail||Chinese standard 60kg/m-75kg/m rails|
|Head width b||±0.5||±0.5|
|Foot width B||+1.0,-0.5||+1.0,-0.5|
|Web thickness e||+0.8,-0.5||+1.0,-0.5|
|Rail height H||±0.8||±0.6|
|Point height m||+1.0,-0.5||+0.75,-0.5|
|Web height h||+0.3,-0.7||+0.6,-0.5|
Compared with the water mist process, the tensile strength of the rail increased by about 50MPa, the hardness of the tread increased by about 10HBW, the hardness fluctuation value of the tread decreased by about 10HBW, and the hardness of the cross section increased by 1-2HRC as a whole.So Baotou Steel can produce TB/T 2344 steel rails equals to GOST R 51685 P65 steel rails and the rails have better performance than the standard specified.
Other kinds of hot sale steel rails
The 50 kg/m, 60 kg/m (60, 60 N), 75 kg/m (75, 75 N), 60AT1, 60AT2 steel rails produced according to TB/T 2344 standard with the steel grades of U71Mn and U75V mainly supply domestic railway line section and have been exported to Vietnam,Kenya and other countries.Baotou Steel also produce the European standard EN 13674-1 54E1, 60E1 and 60E2 steel rails as well as UIC860 standard UIC54 and UIC 60 steel rails with the steel grade of 900A.