Drilling Formula Guide now available on ebay

Now published on waterproof paper (resistant to sweat and Drilling Mud!). As requested by users of the guide.

This A6 sized pocket guide will fit in your top pocket for easy reference for any drilling formula you might need.

Waterproof pocket guide will cost AU$40.00 + P&P.

All formulae have worked examples.

Buy it now on ebay - https://www.ebay.com.au/itm/Drilling-Well-Control-Formula-Handbook/29241...