Key Energy Services Inc. has agreed to buy certain assets of OFS Energy Services LLC in a cash-and-stock deal valued at $222 million. The deal will expand the Houston-based onshore well service rigs providerâ¿¿s total fleet of coiled tubing units by 78 percent and double its shale market presence since the beginning of the year, according to Dick Alario, president and chief executive officer of Key Energy (NYSE: KEG). As part of the agreement, the company will pay $75.6 million in cash and offer 15.8 million shares of its stock to Boston-based ArcLight Capital Partners LLC, the parent company of privately held OFS Energy, which was founded in 2006. The shares are worth about $146.8 million based on the July 23 closing price of $9.29. Key Energy expects to close on the deal in the third quarter. At that time, OFS will own about 11 percent of its 125 million shares outstanding. The Houston-based OFS Energy assets being acquired include oilfield services companies Davis Energy Services, based in Marshall; Swan Energy Services, based in Jacksboro; and Quail Energy Services, based in Midland. Combined, the subsidiaries employ about 880 people and operate in the Haynesville Shale, Barnett Shale, Woodford Shale, and Permian Basin markets. All three generated about $81 million in revenue for the first six months of the year. Also included in the purchase are eight coiled tubing units (with two additional units scheduled for delivery this year), 34 workover rigs, 123 vacuum trucks, 10 salt water disposal wells, three drilling rigs and a well-site construction business. Research firm Jefferies & Co. wrote in a research note Monday that Key Energy represents "one of the best plays on the re-emergence of oil drilling activity in the U.S." The firm went on to say that Key Energy's international growth initiatives set it apart from other North American companies.