Strap-welding 36" bit

Dear members

We'd value your opinions (and experience) associated with strap-welding 36" bits.

Based on a failure many years ago, it would seem to have become custom-and-practice with some Drilling Supervisors in this region. The wells are being drilled from jack-ups to accommodate 30" conductor.  High vibration is seen and effective ROP (incl. connection and hole conditioning whilst drilling) is 11 ft/hr.

Not only does it consume valuable rig time doing this strap-welding, but the Drilling Contractor (who is contracted to provide the bit subs and cross-overs) won't allow their subs to be welded across and so the operator has the additional expense of providing bit subs.

Please can you let us know what you're doing in your operations (strap-welding or not) and also advise if you know whether this is an acceptable practice.  Furthermore, what alternatives are there?

It would also be good to know if anyone has any ideas to improve effective ROP.

Thanks

Dave

11 Answer(s)

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