Line K Self-Quiz: Regulators

Question 1

2If the orifice in the restricting element of a pressure regulator is too small, the :

a) pressure on the downstream side of the regulator will become too high
b) regulator will hunt
c) regulator will close rapidly
d) restricting element will fully open and not maintain required downstream pressure

Answer 1

d)

Question 2

When selecting the components of a service regulator, the required downstream pressure will be determined by the selection of the:

a) proper body size
b) loading element (spring)
c) measuring element (diaphragm)
d) restricting element

Answer 2

b) loading element (spring)

Question 3

An appliance regulator is allowing gas pressure to fluctuate above and below its set point. This can be caused by

a) completely plugged pilot tube
b) pinhole in the diaphragm
c) too large of a vent opening
d) a partially plugged vent opening

Answer 3

d) partially plugged vent opening

Question 4

All appliance regulators require a vent to allow

a) the diaphragm to move up and down freely
b) gas to escape when the diaphragm ruptures
c) gas to escape if the relief valve opens

Answer 4

a) diaphragm to move up and down freely

Question 5

The maximum pressure in a natural gas piping system extending from the termination of the utility inside a building shall not be higher than ____ for a single family dwelling

a) 1/2 psig
b) 1psig
c) 2psig
d) 5psig

Answer 5

c) 2psig

Question 6

A moisture exhaust duct from a domestic clothes dryer shall terminate at least _____ from a service regulator vent

a) 3 feet
b) 5 feet
c) 7 feet

Answer 6

a) 3 feet

Question 7

A propane service regulator vent should terminate a minimum of _____ from appliance air intake

a) 3 feet
b) 5 feet
c) 7 feet
d) 10 feet

Answer 7

10 feet

Question 8

Which of the following terms describes the pressure needed to fully close the regulator?

a) offset
b) equilibrium
c) lock up
d) set point

Answer 8

c) lock up

Question 9

When discussing gas regulators, the term droop is used to describe the

a) gas pressure at lockup
b) gas pressure below set point
c) gas pressure above set point

Answer 9

b) gas pressure below set point

Question 10

The K factor of a gas regulator loading spring is the

a) spring rate
b) coefficient of expansion
c) lockup range
d) percentage of kanthol in the spring

Answer 10

a) spring rate

Question 11

Which of the following is the best selection of the regulator components that will provide stable control over a specified range?

a) largest orifice, lightest spring range, largest diaphragm
b) smallest orifice, largest diaphragm, lightest spring range
c) heaviest spring range, largest orifice, largest diaphragm

Answer 11

b) smallest orifice, largest diaphragm, lightest spring range

Question 12

The area inside a regulator known as the vena contracta is an area made of

a) lower than downstream pressure
b) higher than downstream pressure
c) slow gas flow

Answer 12

a) slower than downstream pressure

Question 13

In the discussion of regulator performance, boost is a term that describes

a) critical flow
b) stopper affect
c) the pressure at the vena contracta
d) pressure above set point

Answer 13

d) pressure above set point

Question 14

An integral twin-stage regulator should only be used when piping lengths do not exceed a maximum of ___ feet

Answer 14

30 feet

Question 15

The B149.1 Code requires a shut off valve to be installed:

a) upstream of every regulator
b) downstream of every regulator
c) both upstream and downstream of every regulator

Answer 15

a) upstream of every regulator