Question 28General Subjects - QMED70% to pass
When reading a pressure that fluctuates severely on a direct reading pressure gauge, what should be done?
AI Explanation
The correct answer is B) The pulsation dampening needle valve should be throttled down (without closing) until the fluctuation ceases.
When reading a pressure gauge with severe fluctuations, this indicates that there is excessive pulsation in the system. Throttling down the pulsation dampening needle valve will help to stabilize the pressure reading by restricting the pulsations. This is the proper procedure to obtain a more accurate and stable pressure reading.
Option A is incorrect because simply averaging the maximum and minimum pressures does not address the root cause of the pulsations. Option C is also incorrect for the same reason. Option D, opening the needle valve wider, would have the opposite effect and would likely increase the pulsations, making the pressure reading less stable.
Related Questions
#26 Which of the following direct reading pressure gauges is capable of measuring two pressures and displaying the difference between the two? #27 Which of the following system applications would require the use of a siphon tube (pigtail) to prevent gauge damage? #29 If a standard bourdon tube type pressure gauge that is designed to measure and display gauge pressure reads 43.8 psig, what would be the equivalent absolute pressure? #30 When determining the level of a potable water hydro-pneumatic header tank fitted with a tubular sight glass, what must be taken into consideration? #31 What statement best represents the characteristics of innage and ullage tank soundings?