Milwaukee-based mining-equipment manufacturer Joy Global Inc. is looking to expand its offerings by inking a deal to buy LeTourneau Technologies Inc., Houston, for $1.1 billion in cash. Owned by Rowan Cos. Inc., LeTourneau produces oil-and-gas and mining equipment, including the world's largest wheel loaders and the only machines of that type to run exclusively on electricity. The deal is subject to regulatory approval, which the firms expect to receive in two months.