我厂煤场用MQ5／40装卸桥，起重量为5t，跨度40m，结构形式为构架式。该设备系散件到货，现场拼装、焊接。其中桥架拼装焊接完成后，检测发现小车轨距严重超标，桥架备节点内立杆由上到下向内均匀收缩。为此，有关单位进行了相应处理，但未能奏效。一、形变量测量为直观表达， I plant coal yard with MQ5 / 40 loading and unloading bridge, lifting capacity of 5t, span 40m, the structure of the framework for the type. The equipment is delivered in pieces, on-site assembly, welding. After assembling and welding the bridge, the test found that the gauge of the car was seriously over-standard, and the pole inside the bridge prepared node shrank uniformly from top to bottom. To this end, the relevant units were dealt with, but failed to work. First, the deformation measurement for the intuitive expression,