• Core Laboratories , Amsterdam, Netherlands, has acquired privately held Promore Engineering Inc. The combined companies plan to enter the market in Mexico. • Dover Corp., New York City, has sold its A-C Compressor business to GE Power Systems, a subsidiary of General Electric Corp. A-C Compressor is comprised of three operating companies: A-C Compressors in Appleton, Wis.; Conmec Turbomachinery Engineering in Bethlehem, Pa.; and Preco Turbine and Compressor Services in Houston. • Input/Output Inc., Stafford, Texas, has acquired all of the outstanding equity investments of Geophysical Instruments AS . • National-Oilwell Inc. , Houston, has acquired Rye Supply Co. Inc., which operates eight distribution locations in west Texas and New Mexico. • Nabors Industries Inc., Houston, has purchased two jackups to be upgraded and used for long-term contracts with Saudi Aramco Mobil Refinery Co., from Santa Fe International Corp., Dallas, for $27.5 million, cash. • Superior Energy Services Inc., Harvey, La., has acquired Power Offshore Service LLC and Reeled Tubing LLC for $80.5 million. Assets include eight liftboats and 21 coiled-tubing units and related equipment. • Varco International , Houston, has acquired capital stock of Albin's Enterprises Inc., a coiled-tubing/wireline- products business. It will operate as Hydra Rig. • NQL Drilling Tools Inc., Nisku, Alberta, has merged with NorthStar Drilling Systems Inc. for 0.2 NQL share per NorthStar.