The branch line for the desuperheater leakage test sample cooler is located between which components?

• A. Between the outlet of the motor operated gate valve and the inlet of the manually operated stop-check valve to the 600 PSI steam main
• B. Between boiler and main steam line
• C. In the feedwater line after the pump
• D. In the exhaust line of the boiler

Answer: (A)

The branch line for the desuperheater leakage test sample cooler is placed on the outlet side of the motor‑operated gate valve and before the manually operated stop‑check valve that feeds the 600 PSI steam main. This position isolates the desuperheater sampling path from the rest of the steam system while still allowing steam to flow into the main when the valves are aligned for normal operation. The gate valve provides clean isolation for testing, and the stop‑check valve prevents backflow from the high‑pressure steam main into the branch, ensuring an accurate leakage test of the desuperheater circuit.

If the branch were located elsewhere, such as in the boiler-to-main line, in the feedwater line after the pump, or in the boiler exhaust line, the test wouldn’t accurately isolate and sample the desuperheater area, leading to improper readings or unsafe conditions.