Question 404General Subjects - Assistant Engineer

The correct answer is D) fully opened. Spur gear pumps should be operated with the discharge valves fully opened to allow for maximum flow and pressure. Throttling or partially opening the discharge valves can lead to excessive back pressure and heat buildup, which can damage the pump components. Fully opening the discharge valves ensures the pump is operating within its designed parameters and prevents potential issues. The other options are incorrect because partially opening the valves (A and B) or throttling them (C) would restrict the flow and create unnecessary back pressure, which is not the recommended practice for spur gear pump operation.