A 10-inch, 600-pound gate on a 660 psig, 720°F superheated steam system could not be operated. Steam was blowing to atmosphere at the rate of 100,000 lb./hr.

Besides costing the company valuable time and energy loss, the dangerous leak was causing noise pollution and was threatening to shut down the plant. The valve had to be replaced on-stream.

A 10-inch hi-stop fitting, taken from Team stock, was sent to the plant after the call came in. Team personnel installed the fitting quickly, and the line was tapped. A special high-stop plug was inserted to stop the steam flow.

Maintenance crews were then able to remove and replace the defective valve without shutting down the system.