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] Federal and state authorities are investigating the cause of the deadly explosion and fire at a natural gas drilling rig in southeastern Oklahoma on Monday. Five workers died in what appears to be one of the country’s deadliest onshore drilling accidents.
[pdf] The bodies of five workers, including one Texan, were recovered Tuesday after an explosion ripped through a drilling rig in Oklahoma, triggering what appears to be the nation's deadliest oil and gas accident since the 2010 Deepwater Horizon disaster in the Gulf of Mexico.
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