Welded rail joint order is bottom-up, after the end of the first rail waist rail, rail head, rail crane factory in Hefei, layer by layer by road surfacing, patching around final. Range two ends of each track is 40mm, while preheating, manufacturers design the crane rail, preheat and interpass temperature controlled at 300 ℃ ~ 350 ℃. The first layer of weld (base): Current 120A ~ 130A, in order to prevent permanent steel plate copper plate will burn and melt, thereby reducing the difficulty of removing copper pad, air cooling time shorten the track to facilitate maintaining interlayer temperature, crane rail factory sale, prevent hardening; later layers can be used (130 ± 15) A, each finished welding slag must be cleaned to continue welding; welding rail waist: Current 130 ~ 140A, applying upward from the lower back welding slag attention. Rail usually carbonaceous, high manganese steel (C = 015% ~ 018%, Mn = 016% ~ 115%) from rolling. Typical materials for U71Mn steel crane rail. Square steel main square with the Q275 steel or steel crane rails are special cross-section of the rail and the car used by Crane, the standard length of 9,915,10,1015,11,1115,12,1215 etc. eight kinds. Common specifications for QU70, QU80, QU100, QU120, QU behind the numbers that track width of the head. Railway heavy rail and light rail sub-2 crane rail factory business, exhibition of Commerce Bo (certification), Hefei rail crane manufacturers to provide the Hefei exhibition Bo Trading Company. Hefei Show Bo Trading Company (www.hfzhanbo.com) (www.hfzhanbo.com) is Hefei, steel leaders, over the years, the company implement the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customers needs. In the exhibition of Commerce Bo leadership with the staff warmly welcome all inquiries negotiations to create the exhibition of Commerce Bo better future.