HOUSTON—A machine-tending robot has improved productivity and saved jobs at a manufacturer of oil- and gas-drilling equipment here.

WEIRTON, WV—Pietro Fiorentini USA, a manufacturer of oil and gas control systems, plans to open a $9 million assembly plant here. The plant could employ 150 when fully operational.

PEARLAND, TX—CapRock Oil Tools, a manufacturer of drilling bits and other equipment for oil rigs, has moved to a new assembly plant here.

GRAY, LA—Standard Crane and Hoist has opened a new plant here to build equipment for the oil and gas industry.

BYNUM, MT—Yates Constructors is building an assembly plant here to make equipment for processing Canadian oil sands. The facility will hire 75 to 100 workers beginning in April.