The failure analysis of the drilling rig hoisting steel wire rope

Drilling rigs belong to the lowest-safety level of hoisting rope systems. The valid regulation for drilling permits the usage of steel ropes on condition that their permanent safety does not decrease under the value 2.5. Considerable dynamic and cyclic stresses, abrasion and corrosive environment generated during the operation cause rapid fatigue and rope damage. The stress of the rope in operation leads to the specific precautions ensuring the safety rope work. The specific precautions include monitoring of the rope tractive work measured in tonne-kilometres (ton-kilometres services). The working part of the hoisting ropes of the drilling rigs - after the stated number of tonne kilometres was worked off - is slipped and a regular non-destructive rope test (NDT) is recommended. Rope under sizing, failing in rope slipping program and non- implementation of NDT controls led to the situations endangering the drilling crew safety. After the critical situations the operator decided to perform the analysis of the condition of all ropes.