drill head blocked not stuck!, page-9

It's a mechanical issue with the air hammer, hence the term blockage. Most likely with 1 of the 2 flow valves in the air hammer, behind the bit (visualise a piston).

Pulling out/running back in the hole are referred to as a Trip. For a 1266m hole, this could b 18-24 hrs + the inspection & replacement of the valves. They can switch back to the rotary table instead of using the air hammer, was working allright b4. Only bonus with air hammer drilling is the faster rate of drilling.

Since we have a kinked section (actual term is 'dogleg' or a 30-40 degree angle hole from 488m to 1266m), tripping out will b slow for the lower portion & faster for the vertical hole. Don't think the crew will worry much about a wet rigfloor, should have anti-slip mats.

Nothing major, just another day in the oil patch.

Meanwhile refer this brochure frm Weatherford.