Regulator Assignment 1 + 2

Question 2

What are the two main purposes of gas pressure regulators?

Answer 2

1. Reduce and maintain pressure downstream
2. Regulate and adjust pressure

Question 3

What are the four categories of gas pressure regulators?

Answer 3

1. Service
2. Line
3. Appliance
4. Two-stage

Question 4

What is “lock-up pressure” and how do you check it?

Answer 4

Pressure above set-point that shuts regulator down

Close the valve and measure downstream pressure

Question 5

Where is the hydrostatic relief valve used?

Answer 5

Liquid propane system for when propane is tapped between two shut off valves

Question 6

What must be the size of the vent piping from a relief device?

Answer 6

Same size as the vent opening

Question 7

What are the three elements of a direct operated regulator?

Answer 7

loading, measuring, restricting

Question 8

When flow rate increases through a regulator, what happens to the downstream pressure?

Answer 8

IT decreases.

Question 9

What is the maximum allowable propane pressure in a building?

Answer 9

20-25psig

Question 10

What controls the downstream pressure in a regulator?

Answer 10

Loading element/spring

Question 11

What is the difference between a zero-governor and an air/gas ratio regulator?

Answer 11

Zero gov keeps downstream pressure at 0 and only allows flow through negative pressure signal & air/gas keeps ratio constant even during air pressure changes

Question 12

What type of regulator arrangement is required in all permanent propane installations?

Answer 12

Two-stage

Question 13

Will gas Flo be interrupted by changing a propane cylinder if an automatic changeover regulator is used on the installation?

Answer 13

No. Auto-changeovers allow no interruption

Question 14

What 5 factors need to be considered before selecting a regulator?

Answer 14

1. inlet pressure
2. outlet pressure
3. pipe size
4. gas type
5. btuh

Question 15

Under what conditions can a leak limiter be used?

Answer 15

Ventilated space only

Question 16

Maximum allowable leakage rate for leak limiter installed on a natural gas regulator?

Answer 16

2.5ft3

Question 17

Maximum allowable leakage rate for leak limiter installed on a propane regulator?

Answer 17

1ft3

Question 18

Should the arrow on a regulator body point upstream?

Answer 18

NO

Question 19

What is the minimum clearance allowed between the vent termination of natural gas regulator and a building opening?

Answer 19

36”

Question 20

What is the maximum allowable pressure downstream of a pressure controlling device?

Answer 20

Max allowable inlet pressure of appliance furthest downstream

Question 21

What are the most commonly used overprotection devices?

Answer 21

Relief valves

Question 22

Does a relief valve decrease a regulators capacity?

Answer 22

No

Question 23

What measures the system pressure when using a direct operated relief valve?

Answer 23

diaphragm senses upstream pressure via a sensing line

Question 24

What types of overpressure protection incorporates a restricting element?

Answer 24

All relief types

Question 25

if the type of system and the pressure ranges safely handled by the system are known, how should a relief valve be chosen? (3)

Answer 25

1. continuity - can flow be interrupted
2. safe discharge - where will gas go
3. detectability of failure - how does it

Question 26

Does an overpressure shut-off (OPSO) automatically reset?

Answer 26

NO, manual

Question 27

What would happen if a regulator vent became blocked with the regulator in the open position?

Answer 27

It can not close

Question 28

Which type of monitor, wide-open or working, is less likely to have operating problems? Why?

Answer 28

Working, because it is being exercised

Question 29

What are the min and max allowed set pressures for a line relief device installed on a 2psi piping system?

Answer 29

We do not need a relief