back hand welding is when you pull the welding rod or whatever it is that you are using and forehand is when you push it ahead
what is the difference between ultrasonic welding & radiographic welding
"Automotive" means that such a person is specialized in cars.
SAW welding is a type of arc welding while ERW welding is spot or seam welding. SAW stand for submerged arc welding while ERW stands for electric resistance welding.
EFW: Electric Fusion Welding is a more general term which includes Electric resistance welding (ERW) and other types of welding such as Arc welding.
The only difference between the two is that projection welding requires preparation of the joint members in the way of adding a preformed dimple or projection. Spot welding is used without such preparation to the joint members. it's just heat and pressure.
what is the difference between ultrasonic welding & radiographic welding
The prehaet temperature is taken before welding starts. The interpass temperature is taken between welding passes.
"Automotive" means that such a person is specialized in cars.
in arc welding only heat is used to weld metal. but in resistance welding pressure will also be used along with heat.
SAW welding is a type of arc welding while ERW welding is spot or seam welding. SAW stand for submerged arc welding while ERW stands for electric resistance welding.
There's some information on welding at http://www.WeldingFun.com .. should have the answer your looking for. Sorry for being to lazy to look it up
The main difference between these two types of welding is that GTAW uses gases to create the weld whilst SMAW uses an an electrical current. Both are very popular welding processes.
If by gas welding you mean-oxyacetylene welding. The difference is just that arc welding requires a darker shade of lens. When oxyfuel gas welding (OFW) usually a shade 5 lens is recommended. When arc welding, a minimum of shade 10 lens should be used (actually shade should be determined by amount of current used).
Shielded welding needs a gas to shield the weld from the atmoshere air. Unshielded uses a flux the burns when welding to shield the weld from the atmoshere air.
what is the difference between 7018 and 7018-1
EFW: Electric Fusion Welding is a more general term which includes Electric resistance welding (ERW) and other types of welding such as Arc welding.
The only difference between the two is that projection welding requires preparation of the joint members in the way of adding a preformed dimple or projection. Spot welding is used without such preparation to the joint members. it's just heat and pressure.