Question 263General Subjects - Assistant Engineer70% to pass
Assuming that the flow is from left to right on the illustrated pneumatically operated diaphragm actuated control valve, what statement is true? Illustration GS-0051
AI Explanation
The correct answer is B) Inlet pressure acts on the lower surface of the top disc and the upper surface of the bottom disc for the purpose of achieving hydraulic balance so that inlet pressure does not influence the valve position.
This is correct because in a pneumatically operated diaphragm actuated control valve, the inlet pressure is designed to act on the opposing surfaces of the top and bottom discs. This creates a hydraulic balance, ensuring that the inlet pressure does not impact the positioning of the valve. The other answer choices do not accurately describe the inlet pressure acting on the disc surfaces to achieve this hydraulic balance.
Related Questions
#261 Suppose the illustrated pneumatically operated diaphragm actuated control valve is used to control the fuel oil outlet temperature of a steam-heated heavy fuel oil heater by controlling the steam flow. What would be the result if the stem packing was over-tightened and the stem was unable to vertically move in either direction? Illustration GS-0051 #262 Suppose the pilot controller for the illustrated pneumatically operated diaphragm actuated control valve is supplied with 20 psig control air and is designed to operate the valve with a pilot pressure ranging from 3 to 15 psig. What would be the indication of a properly adjusted spring #264 In the illustrated pneumatically operated, diaphragm actuated control valve, what statement is true concerning the opening and closing forces acting upon the control diaphragm? Illustration GS-0051 #265 Referring to the illustrated pneumatically operated diaphragm actuated control valve, what statement is true? Illustration GS-0051 #266 Suppose the illustrated pneumatically operated diaphragm actuated control valve is used to control the fuel oil outlet temperature of a steam-heated heavy fuel oil heater by controlling the steam flow. What would be the result if there was a complete loss of pilot air being delivered to the valve actuator? Illustration GS-0051