The frame of mast derrick that is designed for hydraulic wheel tractor hoist adopt welding of armor plate,its section is oblong armor plate,and its material is HG60.是什么意思_The frame of mast derrick that is designed for hydraulic wheel tractor hoist adopt welding of armor plate,its section is oblong armor plate,and its material is HG60.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句