Level 1

Question 1

1ft cubed = how many gallons?

Answer 1

7.48gal

Question 2

F* to C*

Answer 2

F* = (1.8 × C) + 32

Question 3

Absolute zero F/C

Answer 3

-460/-273

Question 4

Density of water

Answer 4

62.4 lb/ftcubed

Question 5

1 psi = ?inHg

Answer 5

2.04inHg (29.92÷14.696)

Question 6

Y=
O=
C=
G=
R=
W=
Aux=

Answer 6

Y= compressor
O= Reversing valve
C= common
G= Fan
R= 24v power
W= call for heat
Aux= aux heat

Question 7

Weight =

Answer 7

Mass x gravity

Question 8

Specific gravity =

Answer 8

Density of substance/ density of water

Question 9

Specific volumn of air

Answer 9

13.33ft3/lb

Question 10

Specific volumn (ft3/lb) is the inverse of

Answer 10

Density (lb/ft3)

Question 11

Boules law equasion

Answer 11

V2 = p1 x v1 / p2

Question 12

Charles law equation

Answer 12

V2 = v1 x t2/ t1 or p2 = p1xt2/t1

Question 13

What do you need to do before calculating gas laws?

Answer 13

Change the temp and pressure to absolute values (psia/R)

Question 14

General law of perfect gas

Answer 14

P1xv1/t1 = p2xv2/t2
Eg p2= p1xv1xt2/ v2xt1

Question 15

Work calculation

Answer 15

Force(lb) x distance (lb)

Question 16

1hp = x watts

Answer 16

746 watts

Question 17

1 hp = x ft-lb/min

Answer 17

33,000 ft-lb/min

Question 18

1 hp = x btu/hr

Answer 18

3413 btu/h

Question 19

What temp is soldering done?

Answer 19

Under 840*F

Question 20

What temp is brazing done at?

Answer 20

Above 840*F

Question 21

Backfire

Answer 21

Flame extinguisher with a loud cracking sound.
Caused by low flow pressure

Question 22

Flashback

Answer 22

Flame begins to burn inside the tip
Shrill hissing or squealing
Caused by incorrect pressures

Question 23

Carburizing flame

Answer 23

Excess acetylene
Deposits carbon on base metal
Blue inner core
Yellow white feather
Outer flame

Question 24

Neutral flame

Answer 24

Equal amount of O2 and acetylene
Use for brazing
Slightly rounded, blue white inner cone
Outer flame

Question 25

Oxidizing flame

Answer 25

Excess oxygen
Sharp pale blue inner cone
Shorter, ragged outer flame

Question 26

Order to start oxyacetylene torch

Answer 26

Acetylene first
To close, oxygen first

Question 27

Heat and torches tip relationship

Answer 27

Smaller tip for lower heat and smaller tubing
Larger tip for higher heat and larger tubing

Question 28

Usable plug at the bottom of an acetylene tank will melt at ___*F

Answer 28

212F (100C)

Question 29

The weight if a cylinder before refrigerant us added is called:

Answer 29

Tare weight

Question 30

An acetylene cylinder is pressurized to ___ psi at 70*F

Answer 30

250 psi

Question 31

A _____ is used to reduce cylinder pressure to working pressure

Answer 31

Pressure regulator

Question 32

The working pressure that is considered normal for soldering (psi)

Answer 32

5 psi

Question 33

The outle hose on an acetylene regulator has a special _____ threaded male fitting

Answer 33

Left-handed

Question 34

An air-acetylene torch will reach a max temp of . . .

Answer 34

3600*F

Question 35

High velocity tips (for brazing) require _____ psi work pressure

Answer 35

15 psi

Question 36

A type of check valve with a built in flame arrestor that is installed in the supply hose of a torch to prevent the flame from traveling inside the hose to the supply tank

Answer 36

Flashback arrestor

Question 37

The hardening of soft copper due to repeated bending or happering

Answer 37

Work hardening

Question 38

Oxygen cylinders are charged to ___ psi at 70*F

Answer 38

2200 psi

Question 39

Backfire

Answer 39

Improper operation of the torch tip may cause the flame to extinguish with a,loud cracking sound