What is meant by spot welding?
What is meant by spot welding?
Spot welding (also known as resistance spot welding) is a resistance welding process. This welding process is used primarily for welding two or more metal sheets together by applying pressure and heat from an electric current to the weld area.
When would you use spot welding?
Spot welding is typically used when welding particular types of sheet metal, welded wire mesh or wire mesh. Thicker stock is more difficult to spot weld because the heat flows into the surrounding metal more easily. Spot welding can be easily identified on many sheet metal goods, such as metal buckets.
What are the types of spot welding?
The types are: 1. ‘Pedestal Type’ Machine 2. Resistance Butt or Upset Welding 3. Flash-Butt Weld 4.
What is the procedure for spot welding?
Spot Welding
- Electrodes seated in a weld head are brought to the surface of the parts to be joined and force (pressure) is applied.
- Current is applied through the electrodes to the workpiece to melt the material.
- Current is removed but electrodes remain in place at force to allow the material to cool and solidify.
Why is spot welding important?
Spot welding is considered to be one of the most efficient welding processes and is typically used to merge two or more metal sheets into one. To make this possible, the welder has to apply not only immense pressure and heat but also an electrical current through the sheets to eliminate resistance and make them fuse.
What are the advantages of spot welding?
The main advantages of spot welding are that it does not require any filler metals and gases for joining the metal pieces. It is easy to join the metals using this type of welding process and does not require any high skilled labours or technicians.
What are the 3 stages of spot welding?
Spot Welds Parameter
- Electrode Force. The electrode force is required to squeeze the metal sheets to be weld and joint together.
- Squeeze Time. Squeeze Time is the time interval between the initial application of the electrode force on the work and the first application of current.
- Weld or Heat Time.
- Hold Time.
- Weld Current.
What is the difference between arc welding and spot welding?
What is the difference between Arc welding and spot welding? Arc welding uses an electric arc – a big spark – to heat and fuse metal, including filler metal. Spot welding uses electric resistance – current flow – to join pieces with no filler.
Which one is a disadvantage of spot welding?
Joining two pieces of metal together by spot welding can be quick and efficient, but the resulting join will not be adequate for all purposes. It can be weak or deformed, particularly if the method is not used correctly.
What are the defects of spot welding?
Common Causes of Resistance Spot Welding Defects
- Weld Current Low.
- Weld Current High.
- Weld Force Low.
- Weld Force High.
- Weld Time Short.
- Weld Time Long.
- Squeeze Time Short.
- Hold Time Short.
Which type of power source is used in spot welding?
Because DC power supplies offer the best low energy control, it is the best choice for welding fine wires and thin foils. High frequency inverter technology utilizes pulse width modulation circuitry to control the weld energy.