Drill pipe with tool joints can be determined by their configuration or upset on both ends. The upset of the drill pipe allows welding of the tool joints and can be categorized as: 1. Internal Upset (IU): The dril.
[pdf] DTH is short for “down-the-hole”. Since the DTH method was originally developed to drill large-diameter holes downwards in surface-drilling applications, its name originated from the fact that the percussion mechanism followed the bit down into the hole. Applications were later found for the DTH method underground, where the direction of drilling is generally upwards instead of downwards.
[pdf] There is dirt stuck in the wind flap or other rotating parts 1. Send the minor repair station in time to remove or replace the necessary parts. 3. If you use the air duct to refuel, do not add too much fuel at a time, but you must work hard.
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