LIAO Mahong, DAI Hong, YANG Han, et al. Research on gas pressure welding quality of 75N U95Cr hypereutectoid rail for heavy haul railways[J]. Eletric Welding Machine2021, 51(9): 91-94.DOI: 10.7512/j.issn.1001-2303.2021.09.17.
Research on gas pressure welding quality of 75N U95Cr hypereutectoid rail for heavy haul railways
In order to better meet the requirements of rails with high wear resistance on heavy haul railways such as Daqin and Shuohuang
Panzhihua Iron and Steel Group has developed 1330 MPa high-wear-resistant U95Cr hypereutectoid rails.Reliable
stable and efficient welding technology is urgently needed in site rail welding construction. In this paper
experimental studies on welding and normalizing process of 75N U95Cr rails were carried out by the GPW-1200 digital control gas pressure welding machine. The results show that the hardness of U95Cr welded joints with this set of process parameters(The first stage: Acetylene/oxygen 111/107 SLM
welding heating for 270 s; the second stage: Acetylene/oxygen 92/87 SLM
welding heating for 90 s) meets the requirements of "Technical Conditions for Gas Pressure Welding of High-Wear-Resistance
High-Strength-Toughness Hypereutectoid Rails for Trial Laying Tests"
and the drop weight
static bending
fatigue
tensile
impact
metallographic and grain size meet the requirements of TB/T1632.4 "Gas Pressure Welding". The performance of the gas pressure welding joints is stable and reliable
which is equivalent to the performance of the flash welding joints.