Electro-Slag Welding Flashcards
In electro-slag welding, where is the pool of molten metal located?
How does it stay there?
Where does it move to?
In this process, a pool of molten metal is contained between two water-cooled copper shoes, which travel upwards as the weld metal solidifies.
List the steps of the Electro-slag welding process (4)
- A large gap between two thick vertical plates is filled with flux.
- An electric arc melts the flux forming molten slag, electric current keeps it molten.
- Molten slag melts the continuously-fed filler wire and the plate edges.
- Water-cooled shoes on either side prevent the molten metal escaping and cool it.
What type of electrode is fed into the weld pool?
A bare metal electrode is fed into the weld pool.
How and where is the arc struck?
An arc is struck on the piece of scrap plate attached to the bottom of the joint.
What does the arc do to the flux?
Grains of flux, which have been added, is melted by the arc.
When is the arc extinguished?
When the joint is full with molten flux the arc is extinguished.
What causes resistance heating?
The high resistance of the molten slag to the current flow causes resistance heating
Is Electro-slag welding fully automatic?
It is fully automatic.
What does resistance heating cause?
It melts the electrode and the sides of the joint, fusing them together.
Name some applications of Electro-slag welding
Used to join thick steel plates, e.g. tank walls, ship plates
Name some pros and cons of electro-slag welding
Pros: Fast, unlimited thickness of workpiece, low distortion
Cons: Plates must be vertical, expensive
What must be labelled on a diagram for electro-slag welding?
Label electrode wire feed, guide tube, power supply, weld, starting plate, welded pieces, molten slag, weld pool,
