5.6　Tower Crane

5.6.1　Construction method statement shall be developed for installation of tower crane，and shall comply with the requirements defined in Article 4.2.2 herein.

5.6.2　Whenever crane boom luffs，the tonnage of the overload limit device shall be adjusted timely depending on the working radius and the weight of the workpiece.

5.6.3　While tower crane is lifting/lowering a workpiece，its boom shall not luff.Additionally，luffing shall not take place in pace with any of the other three actions（traveling，swiveling and lifting/lowering）.

5.6.4　Rail clamping device shall be tightly engaged when tower crane is taken out of service.

5.6.5　Where two tower cranes are operated on the same track or on two adjacent tracks，a minimum distance of 5m shall be maintained between any adjacent components of these two tower cranes（including the workpiece to be lifted）.

5.6.6　Where two or more tower cranes are used to lift one workpiece，the lifting load for each tower crane shall not exceed 75% of its rated capacity.