section one work place safety tools & materials Flashcards
list 4 angles of importance & amount on sharpened point of drill bit
1) cutting edge or point angle 59degree
2) included angle 118degree
3) lip clearance 12-15degree
4) dead center angle 120- 130 degree
degree of general cutting edge on a chisel
60-70 degree
chisel use for cleaning up square keyways
cape chisel
Graduations on imperial dial indicators are in how much of an inch?
thousands of an inch
When heavy loads are transmitted between the shaft and the pulley what kind of key is used?
A gib Head key is used.
Which of the following types of portable fire extinguishers is classified as the best type of extinguisher to use on a diesel fuel fire?
Class B
properties of oxygen are
colorless, tasteless, greatly speeds up combustion. (if oil or grease is exposed to pure o2 under pressure, it can explode without flame or spark
o2 used in oxyacetylene system is what % of pure O2
99.5% pure O2
true or false: when a cylinder runs out of gas, you must leave cylinder open
false
how much pressure dose an O2 cylinder take when filled
2175psi or 15000kpa at room temp or 21*C
true or false: the color of cylinder corresponds to content
false whims indicates content
what way would you know if a tank is empty
mt written on tank
when do you remove metal cap on cylinders
when cylinder is on cart & ready to use
what threads would you see on O2 cylinder
r.h thread
what safety component is used on a O2 tank if there would be a fire, or if exposed to high pressure
frangible disk
what pressure will the frangible disk on O2 tank rupture
3200 psi
true or false: when opening an O2 tank you want to open valve all the way
true ( back seat O2 valve)
what’s back seating on O2 tank
when valve is open all the way when in use
at what pressure dose acetylene become unstable
15psi
what are some properties of acetylene
colorless with a garlic like odor & can be smelled at concentration of 1%
acetylene is the same weight as air, what can this cause?
the gasses will collect in pockets & can be considered explosive
why is acetone use when filling acetylene tank
acetylene tank is filled with 40% acetone. acetylene is mixed with acetone for storing past 15psi
what is draw limit referring too on acetylene tank
the maximum amount of acetylene that can be take from acetone
a cylinder must be emptied no faster than____?
a cylinder must be emptied no faster than 1/7th of capacity per hour or less than 7 hours
the maximum safe pressure for acetylene is ___
15psi
how will you be able to tell when acetone is being drawn?
the flame will be cooler & with pale blue color with orange flecks in flame
why is it so bad to draw acetone?
the acetone being solvent will cause damage to tips, plastics, rubber parts of regulator, hoses & torch assembly
why do they use porous filler on acetylene tanks?
the porous filler is used to mix the acetylene & acetone together for safe storage
what safety component is used on a acetylene tank if there would be a fire, or if exposed to high pressure?
fusible metal plug that will melt out at 100*C & allowed a controlled release
true or false: you can exceed draw limit if torch tip is too big
true, if tank is too small and torch tip is too big, you can easily exceed draw limits, see manufacture for consumption spec
common locations for fusible plugs are:
1) on concave bottom of the cylinder
2) a filled passage on the back side if the cylinder valve
3) on the reinforcing collar or neck ring
4) the shoulders of the cylinder
what kind of threads would you see on an acetylene cylinder?
L.H threads would be used
what 2 types of valves are commonly used?
1) recessed valve
2) exposed valve
what would the difference be between 2 valves used?
1) recessed valve dose not need metal cap for storage or transportation & uses t-wrench
2) exposed valve needs the use of metal cap for storage & transportation
when opening valve on acetylene cylinder, how much do you need to open valve
just enough flow for heating & cutting, usually one turn this way in event of a fire can turn tank off quickly
what would another name for propane be?
LPG, or liquid petroleum gas
how much will a LPG tank be filled?
a LPG tank will never be filled more than 80% of max volume
what is recommended speed at witch to use hacksaw
40 to 50 strokes per min
what is the boiling point for propane
-42.2*C
is propane heavier or lighter than air?
propane is heavier
liquid propane when exposed to atmospheric pressures will expand ____ times its volume in gas
270 times its volume in gas
as outside temperatures lower what will happen to LPG?
vapor pressures will lower as temps lower till -42*C then there will be no vapor pressure in cylinder
what is rang of flammability referring to?
rang of flammability is referring to the rang of fuel/air mixtures through witch fuel will burn
what rang of flammability will LPG burn?
LPG will burn if gas in air is between 2.4%-9.5%
true or false: LPG will still burn if range of flammability excides 9.5%?
true, the outer edges of the main body of gas will still be able to ignite & burn & will cause air movement mixing gasses further
is LPG toxic?
no, but can still be deadly by displace oxygen in blood stream. large amounts will cause asphyxiation
what two way would a cylinder or tank be filled?
1) volume
2) weight
what level is the maximum level must a cylinder be filled?
80% to allow the room for expansion
what is the 2 purposes of a regulator?
1) maintain constant pressure as cylinders being used
2) lower tank pressure to a working pressure
what are the 4 different kinds of flames
1)carbonizing flame
2) neutral flame
3) oxidizing flame
$) acetylene flame
what flame do you look for when cutting or heating?
neutral flame
what pressure to use when purging oxyacetylene systems?
5psi on both acetylene & O2
what is minim burst pressure of hose to be used on oxyacetylene
400psi
good tips to prevent flash backs
1) purge each hose individually
2) install 1 way check valves
3) adhere to recommended set-ups & procedures
4) keep equipment in good repair
5) balance gas pressures when heating
what goggles should be used when using oxyacetylene?
4 or #5
what angle would you cut with a cutting torch?
inclined more for thinner materials
