Alert 11 – 20 Drill Line Pulls Through Wire Rope Snake While Stringing Blocks
WHAT HAPPENED:
While in the process of stringing the travelling blocks with brand new drill line, the 1-3/8 inch drill line came free from the Wire Rope Wire Mesh Snake Grip and dropped to the rig floor from approximately 20 meters. The line and snake grip had been reeved through all three sheaves on the off driller’s side and had passed through the first two sheaves on the driller’s side of the travelling block. There was one last sheave on the travelling block to spool.
The snake grip was in good condition and was the correct type for the line. The drill line had been fully inserted into the 1 inch – 1-1/2 inch snake grip right to the rubber boot and then 3 x hose clamps were used to secure the snake grip. The clamps were then covered with tape for about 6 inches on each. The snake grip was then attached to a 3/8 inch wire rope line by back splicing the line’s dead end through the snake grip’s soft eye. The 3/8 inch wire rope is used to pull the drill line through the crown and travelling block sheaves.
There were four essential people involved in the job on the rig floor but none were near the drop zone. The pre job held emphasized the need for the rig floor to be clear. There was no potential for injury.