Our good friend Dave Grafton sent us this important information on rotary rig wire rope to share with our audience.
“From our friends at the British Drilling Association, we have the attached safety alert regarding wire rope.
Some key take – aways are:
- Ensure the hoist drum line pull rating is known.
- Ensure the WLL (Working Load Limit) – in the alert they use the term SWL (Safe Working Limit) – of the hoist rope is known.
- Ensure the WLL of the hoist rope is equal to or greater than the line pull of the hoist drum.
Additionally, if using wire rope clips (clamps): ensure the clip is correct for type of rope and sized for its diameter, ensure that they are installed with the correct number of clips (based on rope diameter), saddle on the “live” end of the rope (https://www.youtube.com/watch?v=audmZA4RCMI), equally spaced along the required turnback length(per manufacturer), tightened to the correct torque value(per manufacturer), and inspected pre-shift. It never hurts to check them on a frequent basis to ensure the rope clips remain tight, but not over-tightened.
If the drill rig is not equipped with an anti-two block device on the hoist line(s), then mark the hoist line with high visibility paint that can be seen from the ground to serve as a warning to prevent a two-block condition. You should also mark the hoist line where the operator can see it from the operating station, as it winds on the drum. Educate and train your employees to constantly watch for a two-block condition. Remember when sitting in a crane, the operator cannot see the tip of the boom. This goes for most piling rigs as well – they can’t see the top of the mast. The employees on the ground must constantly look up to ensure a two block condition is prevented.
If the drill rig is equipped with an anti-two block device, then inspect it pre shift to ensure it is functioning correctly.
And remember, the UK has different requirements then we do here in the US and Canada.”