ABSTRACT
The British Standards Institute have set out rules on water-well drilling equipment, but that august body, the American Petroleum Institute (API) is probably the most famous and deservedly so—long may they reign. Drilling threads are almost always of the API type so, while there are some odd differences with some manufacturers, they are in the minority in the water well industry. Drill collars are the most frustrating, cantankerous, useless, difficult to handle pieces of equipment out of the hole, but in the hole they make money. Drill collars separate the men from the boys. Some drillers like to have a little track and trolley for tool handling. Drill collars tighten onto the thread shoulders whereas drill-pipe tightens onto the thread. A few tips on keeping the well-site tidy, with special reference to the drill string.
