chapter  10
79 Pages

ROTARY DRILLING

Up until the beginning of the 20th century, the drilling of oil wells was done using bits of various fishtail designs. One such design is shown in Figure 10.1.

As force is applied during bit rotation, the rock is literally scrapped away from the bottom of the hole. As one can imagine, this practice could and did work well in soft formations but in the harder, more abrasive formations the wear was high and the penetration rate low. In 1907, Walter Benona Sharp and Howard R. Hughes, Sr. were involved with drilling two test oil wells at Goose Creek and Pierce Junction, Texas. According to the Handbook of Texas (2012), both wells had to be abandoned because of the hard rock encountered. As a result, the two men began to consider the possibility of developing a roller rock bit. It was eventually arranged for Hughes to proceed with the design and construction of a bit with capital provided equally by Sharp and J.S. Cullinan. The result was the Sharp-Hughes rock bit (see Figs 10.2 through 10.4). In 1908, the Sharp-Hughes Tool Company was formed to manufacture the bit and a factory was built at Houston, Texas. Hughes received 50 percent of the stock for his development of the bit and the other 50 percent was divided between Sharp and Cullinan. In 1912, at the time of Sharp’s death, Hughes was given controlling interest. Not long afterward, the company name was changed to the Hughes Tool Company.