The DTH drilling rig (down-the-hole drilling machine) is a kind of drilling machine, which is mainly used for drilling in rock formations. The down-the-hole drilling rig uses the impactor and the DTH drill bit.
[pdf] Precision is equipping its U.S. rig fleet with upgrades to handle the increasing demand for ERL wells, particularly in plays like the Permian Basin, Eagle Ford, and Haynesville. These investments include: Higher torque top drives for better drilling power.
[pdf] Before starting casing, the drilling supervisor should hold a pre-job safety meeting and confirm the following with the crew: 1. Remove unnecessary tools. 2. Good Housekeeping before the job 3. Rig up Casing handling equipment: Using appropriate hand. .
A circulation sub, fitting the casing thread, equipped with a WECO connection, shall be readily available on the rig floor at all times during casing running.
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