Line D Regulators Flashcards
In order to increase regulator accuracy, the pitot tube senses pressure at what point?
Lowest outlet pressure point
Which regulator will have the least amount of droop under flow conditions?
A pilot operated regulator
Critical flow in a regulator occurs when the velocity of the gas reaches what threshold?
Sonic Velocity
What does a double-ported balance regulator use to sense downstream pressure?
A downstream sense line
Where is the sense line connected on a proportional regulator?
To the top of the diaphragm
When zero governor regulators are used for burners that are to be operated under positive or negative combustion chamber conditions, how can the combustion chamber pressure be counterbalanced?Connecting a pressure reference line from the combustion chamber to the top diaphragm chamber of the zero governor
Connecting a pressure reference line from the combustion chamber to the top diaphragm chamber of the zero governor
What type of regulator is pictured below?
Double-ported balanced regulator
In the above image what is the purpose of connecting the sense line?
To sense outlet pressure
In the above image at what point is the sense line connected to the main supply piping?
Downstream to the top of the piping
What type of regulator is pictured below?
Atmospheric regulator
What would happen if the regulator shown below was installed backwards?
It will pass no flow
What would happen if the above regulator was installed upside down?
It would provide lower downstream pressure
When selecting a regulator for a gas piping system, what regulator inlet pressure should you assume there to be when the system is under no flow?
Static pressure (system setting)
For a direct-operated regulator, what amount of droop can be expected?
10-20%, but by code should be no more than 10%
When you need extreme accuracy in high-pressure gas system applications, what type of regulator is best suited for this application?
Pilot-operated
If two or more available regulator springs have published pressure ranges that include the desired pressure setting, for more accuracy you would select the spring with the lower pressure range.
TRUE / FALSE
TRUE
What factors make it beneficial to select a regulator orifice size in the smallest diameter that will handle the desired flow?
Avoids instability and premature wear, Allows for smaller relief valves, Reduces lockup pressure
What is used to determine the required flow of relief valves for a gas system?
The wide-open flow rates of the upstream regulator
What is the maximum droop allowed from a regulator in a gas piping system?
10%
What type of regulator is pictured below?
Pilot operated regulator
