Seam Welding Process
Seam Welding is a type of welding in which the electrodes are in disc form unlike stationary rods & are driven through the motor in the presence of current.
Basic Principle of Seam Welding
Two electrodes made from copper & in circular form are used. An impulse current is applied through one of the discs & pressure through the other on the materials that are being joined.
When the material passes between electrodes they rotate. In this way, the electrode remains in contact with the material for a long time & forms a weld joint progressively unlike spot welding which forms an entire joint at once.
Seam welding core principles are similar to that of the Resistance spot welding. Time, pressure & electricity are used to weld metals together. It is a type of electric resistance welding.
If the current is quickly turned OFF & ON a continuous fusion zone of overlapping nuggets is formed then this process is called as STICH WELDING PROCESS.
The process of seam welding can be controlled to create a variety of welds like
- Spot Welds
- Overlapping Welds
- Continuous Welds
Seam welding machine images
A transformer is used to provide energy to the welding joint in the form of low voltage, high current AC power.
How Current Flows?
The electric current flows in pulses to produce a row of welds along the travel path.
Types of Electrodes
Copper electrodes in discs form are used in this welding. The purpose of the copper electrodes is to keep the heat MINIMUM at the contact surface.
Types of Seam Welding
There are two types of this welding
Forms of Seam Welding
- Standard Seam
- Mash Seam
- Roll spot Welding
When electrode wheels are rotated along the workpieces & continuous series of current pulses are fired then a series of overlapping weld nuggets are formed. Continuous, leak-tight joint is formed as a result of this welding.
In mash welding a small sheets overlap occurs, that is one to two times the thickness of the sheets. When current is applied then sheets are then mashed together which forms a solid-state joint. The thickness of the welded joint is 110-150% of the original sheet thickness. This joint thickness can be reduced at the end by post welding planishing.
Roll spot Welding
In roll spot welding current pulses as the wheel travel across the workpieces to form a separate line of spot welds. The joint formed due to this welding is not a leak tight joint.
Types of Seam Welding Joints
Seam Welding Diagram
Download Seam Welding PDF FromHERE
Seam Welding Symbol/Drawing
Seam Welding Equipment
Download Seam Welding PPT FromHERE
Seam Welding Advantages and Disadvantages
SEAM WELDING APPLICATIONS
Seam Welding Machine Specifications
- Mostly available in circumferential, longitudinal & universal types
- Wide range from 50 KVA to 200 KVA
- Variety of models available i.e. 55-A, 55-B, 55-C
What is Resistance Spot Welding?
The type of welding in which the two contacting surfaces are joined from the resistance obtained from the electric current is known as Resistance Spot Welding. It is a type of electric resistance welding.
What is the difference between seam and spot welding?
There are Lot of similarities in seam welding & spot welding like both techniques make individual welds. The heating principle is the same in both which is OHM’s law. But the main difference is both use different types of electrodes. This welding uses wheel electrodes while spot welding uses point electrode. Seam welds are closer together & produce liquid-tight seals. While spot welds are not close together & are not water-tight. While spot welds are not close together & are not water-tight. Seam welding wheels are not stationary while spot welding wheels are stationary.
Read more about Welding
Read more about Magnetic Pulse Welding
Read more about Types of Welding Joints
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