“To date, our depot has completed the welding of 706 km of 500m-long rails for China-Laos railway. Every rail produced by us is absolutely qualified”, said Hou Mingkun, head of Kunming Track Maintenance and Machinery Depot, on 21 May.
The rail welding of China-Laos Railway is the primary task of the depot in this year. Although China-Laos Railway is a conventional speed railway with a speed of 160 km/h, the depot still strictly controlled the rail welding in accordance with the technical standards of HSR.
They have controlled the source quality of 100m rails, arranged special staff to conduct regular equipment inspection, data analysis and equipment debugging, and established a special equipment management inventory to ensure the normal function of production equipment.
They have strictly controlled the process standards, implement processes according to HSR standard, and uniformly applied standard customized 100m rails, which were tempered and processed into 500m long rails after 17 processes, to ensure that the welding heads are 100% qualified.
The depot has carefully selected the welders with work experience of at least five years and arranged them with six months of pre-job training. For ultrasonic flaw detection, the depot applied a two-person and double-flaw detection operation mode, where two operators respectively use a full-section flaw detector to carry out ultrasonic penetration scanning on the rail head, rail web and rail base of the welding heads, check whether the rail welding head is damaged or not by observing the corrugation diagram indicated on the instrument, and form their own independent judgment results. The welding head is allowed to be delivered only when it is accepted in the two person flaw detection.