Line D Regulators

Question 1

In order to increase regulator accuracy, the pitot tube senses pressure at what point?

Answer 1

Lowest outlet pressure point

Question 2

Which regulator will have the least amount of droop under flow conditions?

Answer 2

A pilot operated regulator

Question 3

Critical flow in a regulator occurs when the velocity of the gas reaches what threshold?

Answer 3

Sonic Velocity

Question 4

What does a double-ported balance regulator use to sense downstream pressure?

Answer 4

A downstream sense line

Question 5

Where is the sense line connected on a proportional regulator?

Answer 5

To the top of the diaphragm

Question 6

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

Answer 6

Connecting a pressure reference line from the combustion chamber to the top diaphragm chamber of the zero governor

Question 7

What type of regulator is pictured below?

Answer 7

Double-ported balanced regulator

Question 8

In the above image what is the purpose of connecting the sense line?

Answer 8

To sense outlet pressure

Question 9

In the above image at what point is the sense line connected to the main supply piping?

Answer 9

Downstream to the top of the piping

Question 10

What type of regulator is pictured below?

Answer 10

Atmospheric regulator

Question 11

What type of regulator is pictured below?

Answer 11

Pilot operated regulator

Question 11

What would happen if the regulator shown below was installed backwards?

Answer 11

It will pass no flow

Question 12

What would happen if the above regulator was installed upside down?

Answer 12

It would provide lower downstream pressure

Question 13

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?

Answer 13

Static pressure (system setting)

Question 14

For a direct-operated regulator, what amount of droop can be expected?

Answer 14

10-20%, but by code should be no more than 10%

Question 15

When you need extreme accuracy in high-pressure gas system applications, what type of regulator is best suited for this application?

Answer 15

Pilot-operated

Question 16

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

Answer 16

TRUE

Question 17

What factors make it beneficial to select a regulator orifice size in the smallest diameter that will handle the desired flow?

Answer 17

Avoids instability and premature wear, Allows for smaller relief valves, Reduces lockup pressure

Question 18

What is used to determine the required flow of relief valves for a gas system?

Answer 18

The wide-open flow rates of the upstream regulator

Question 19

What is the maximum droop allowed from a regulator in a gas piping system?

Answer 19

10%