Exterran Partners LP is buying some Fayetteville Shale-based natural gas compression units from a Chesapeake Energy Corp. subsidiary for $135 million. The purchase from MidCon Compression LLC includes 162 compression units with 110,000 hp that primarily serve BHP Billiton Petroleum Ltd. properties in Arkansas. A five-year contract with BHP would be assigned to Exterran at closing. Exterran Holdings services customers in about 30 countries; Exterran Holdings Inc. owns an equity interest. For Chesapeake, the transaction continues an ongoing plan to sell noncore assets.