HVAC/R Unit 23 Soldering and Brazing
What is the difference between soldering and brazing? - Answer-The difference is the temperature.
Soldering takes place at a lower temp than brazing. But both processes are the same.
What materials are best to wear while soldering, brazing, or welding? - Answer-One hundred percent
cotton treated for flame resistance, leather, or Kevlar clothing are the best materials to wear.
What should NEVER be worn when soldering, brazing or welding? - Answer-Synthetic materials such as
nylon, polyester should NEVER be worn when soldering, brazing, or welding.
What type of pants are ideal for working with torches? - Answer-One hundred percent cotton blue jeans
HVACR techs typically wear gloves when soldering or brazing. What is best for welding? - Answer-
Leather, gauntlet-type welding gloves are preferred.
What is worn when using a torch to protect the technician from harmful radiant energy, flying sparks,
and molten metal? - Answer-Safety Glasses.
_______________ produces very little UV light, whereas welding produces a great deal of _________
___________. This is why a welder's __________ ____________ must be worn over the face at all times
when arc welding. - Answer-Soldering, UV Light; Safety shield
_________________ ______________ produce a hotter and more concentrated flame than air-
acetylene torches because they use pure oxygen to burn the fuel. - Answer-Oxyacetylene Torches
, Oxyacetylene torches use an acetylene cylinder, an oxygen cylinder, a _____________ for each cylinder,
connecting hoses, and a torch handle that mixes the acetylene and oxygen. - Answer-Regulater
_____________ gas is unstable under high pressure an can explode just from being struck or jarred
severely. For this reason, the ______________ gas must be stabilized in the cylinder with liquid acetone.
- Answer-Acetylene; Acetylene
_______________ ____________ can be dissolved in water, forming a carbonated beverage. As the
pressure on a carbonated drink bottle is slowly released, you can observe bubbles being formed within
the liquid. - Answer-Carbon Dioxide
The ___________ in an acetylene bottle works the same way. - Answer-Acetone
It is very important that you NEVER allow ___________ to come in contact with oxygen and acetylene
equipment - Answer-Oil
________________ can become unstable and explode at pressures above 15 psig. Because of
acetylene's instability, it is against ___________ regulations to operate a torch with an acetylene
pressure greater than 15 psi. - Answer-Acetylene; OSHA
Acetylene cylinders must be used only in the ___________ position to prevent the acetone from being
pulled out of the cylinder with the acetylene. - Answer-Upright
Oxygen cylinders should always be stored and transported with their ________________
______________ in place. - Answer-Safety caps
Use no oil or thread sealant on the threads of the ______________ _____________. Go to extreme
measures to keep the oxygen-delivery system clean. - Answer-Oxygen Regulator
What is the difference between soldering and brazing? - Answer-The difference is the temperature.
Soldering takes place at a lower temp than brazing. But both processes are the same.
What materials are best to wear while soldering, brazing, or welding? - Answer-One hundred percent
cotton treated for flame resistance, leather, or Kevlar clothing are the best materials to wear.
What should NEVER be worn when soldering, brazing or welding? - Answer-Synthetic materials such as
nylon, polyester should NEVER be worn when soldering, brazing, or welding.
What type of pants are ideal for working with torches? - Answer-One hundred percent cotton blue jeans
HVACR techs typically wear gloves when soldering or brazing. What is best for welding? - Answer-
Leather, gauntlet-type welding gloves are preferred.
What is worn when using a torch to protect the technician from harmful radiant energy, flying sparks,
and molten metal? - Answer-Safety Glasses.
_______________ produces very little UV light, whereas welding produces a great deal of _________
___________. This is why a welder's __________ ____________ must be worn over the face at all times
when arc welding. - Answer-Soldering, UV Light; Safety shield
_________________ ______________ produce a hotter and more concentrated flame than air-
acetylene torches because they use pure oxygen to burn the fuel. - Answer-Oxyacetylene Torches
, Oxyacetylene torches use an acetylene cylinder, an oxygen cylinder, a _____________ for each cylinder,
connecting hoses, and a torch handle that mixes the acetylene and oxygen. - Answer-Regulater
_____________ gas is unstable under high pressure an can explode just from being struck or jarred
severely. For this reason, the ______________ gas must be stabilized in the cylinder with liquid acetone.
- Answer-Acetylene; Acetylene
_______________ ____________ can be dissolved in water, forming a carbonated beverage. As the
pressure on a carbonated drink bottle is slowly released, you can observe bubbles being formed within
the liquid. - Answer-Carbon Dioxide
The ___________ in an acetylene bottle works the same way. - Answer-Acetone
It is very important that you NEVER allow ___________ to come in contact with oxygen and acetylene
equipment - Answer-Oil
________________ can become unstable and explode at pressures above 15 psig. Because of
acetylene's instability, it is against ___________ regulations to operate a torch with an acetylene
pressure greater than 15 psi. - Answer-Acetylene; OSHA
Acetylene cylinders must be used only in the ___________ position to prevent the acetone from being
pulled out of the cylinder with the acetylene. - Answer-Upright
Oxygen cylinders should always be stored and transported with their ________________
______________ in place. - Answer-Safety caps
Use no oil or thread sealant on the threads of the ______________ _____________. Go to extreme
measures to keep the oxygen-delivery system clean. - Answer-Oxygen Regulator
