The early eighties have successfully developed a set of cranecolumn Arm, Arm type cranes, and achieved a national utility model patent.
八十年代初先后研制成功了定柱式旋臂起重机、壁柱式旋臂起重机，并取得了国家实用新型专利证书。
2
The fatigue of steel columns indirectly subjected to crane loading is generally not taken into account. But fatigue failure occurred at the column cap in some workshops.
间接承受吊车荷载的厂房钢柱，一般不考虑疲劳问题，但是在一些车间的钢柱上却出现了疲劳破坏。
3
Several attaching points are usually provided on the column of self-elevating tower crane in connection with the building under construction.