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] On April 20, 2010, an explosion and fire occurred on the Deepwater Horizon semi-submersible mobile offshore drilling unit, which was owned and operated by Transocean and drilling for BP in the Macondo Prospect oil field about 40 miles (64 km) southeast off the Louisiana coast. The explosion and subsequent fire resulted in the sinking of the Deepwater Horizon and the deaths of 11 workers;. BackgroundDeepwater Horizon was a floating —a fifth-generation, ultra-deepwater, , column-stabilized drilling rig owned by and built in South Korea. The platform wa. .
The fire aboard the Deepwater Horizon reportedly started at 9:56 p.m. on April 20. Transocean employees on the vessel stated that the electric lights flickered, followed b.
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