In the application of drilling machinery, the air-leg rock drillcan only drill small-aperture, medium-shallow blast holes; the heavy-duty rail-type rock drill can also drill deep blast holes through the post, but the en.
[pdf] The rotary drilling hose (API7K) is the flexible connector between the top of the standpipe and the swivel that allows for vertical travel. Its lengths are in the range of 45 ft (13.7 m) and over. We generally use rotar.
[pdf] Keep hands off the stump of pipe in the rotary or mouse hole. Only place hands on tong handles. Keep hands off of the tong latch except to open the tongs. Keep an eye on swinging tongs at all times. Stand clear of the spinning chain. Never put your hand on top of the drill pipe or collar box at any time.
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