Emerson Electric Co. agreed to buy Pentair Plc’s valves and controls business for $3.15 billion in cash, broadening its focus on industrial automation under a year-old plan to overhaul operations.

Emerson Electric Co. agreed to buy Pentair Plc’s valves and controls business for $3.15 billion in cash, broadening its focus on industrial automation under a year-old plan to overhaul operations. The ...