Spot welding is used in multiple industries, to join two or more sheet metal components in a lap joint formation. Common applications of spot welding, ordered from greatest to least frequency, include.
- Automotive Industry
- Consumer Goods Industry
- Electrical Industry
- Aerospace Industry
- Manufacturing Construction Industry
- Furniture Industry
- Artistic Applications
The automotive industry has moved on from mild steel in the pursuit of more fuel-efficient and safer vehicles. Using the latest generation of steel alloys such as AHSS/UHSS, which often have a corrosion-resistant layer of zinc to aid in corrosion resistance, which further complicates the welding process choices.
Automotive Spot Welding.
The sheet metal manufacturers have specialized pinch welding procedures that allow for a quality weld. They produce the welding procedure as a recommendation for the auto industry. With the advent of the latest steel alloys incorrect welding processes can weaken the steel from excessive localized heat input. Making resistance spot welding the clear choice.
Extensively used in the assembly of vehicle bodies, in both body-on-frame/ cab over chassis and the unibody/monocoque design that has structural integrity while keeping the weight to a minimum.
The outer panels such as doors, fenders, hoods, and the trunk also use the pinch welding process. The average vehicle can have 3000-5000 pinch welds.
The vehicle repair industry uses for a spot welder are accident and restoration work. If the panel is too badly damaged it is more cost-effective to replace the panel with a replacement part for a quality repair. Smaller in size and not robotic but it is still the same form of resistance welding. The repairers use special spot weld cutters to minimize damage in the removal to the vehicle in the spot weld removal process.
Consumer Goods Industry
Spot welding is used in the production of consumer goods, appliances, and toys. Even spot welding jewelry.
The consumer goods industry is a vast and diverse sector that includes the production of a wide range of products that are used by people in their daily lives. Spot welding is a commonly used manufacturing process in this industry.
Home Appliances: Resistance spot welding is widely used for home appliances, such as refrigerators, washing machines, and air conditioners. These appliances typically consist of metal components either the outer structure or internal bracketry or shelving to hold electrical components.
Automotive: While not explicitly a consumer good, automotive parts that go into the aftermarket are consumer goods. Spot welding is widely used in the manufacturing of automotive parts, such as exhaust systems, replacement panels, oil pans, and fuel tank baffles. These parts need to be joined together securely to ensure safety and reliability on the road.
A Spot welder is also used in the electrical industry to join various components, including lithium-ion battery terminals. Spot welding is also commonly used in the manufacturing of electrical contacts, such as those used in switches and relays.
In the production of batteries for electric vehicles and cordless tool batteries, spot welding is used to join the individual cells together to form a complete battery pack. This process involves welding the positive and negative terminals of adjacent cells together to create a strong and reliable electrical connection.
In the manufacturing of electrical devices and equipment, spot welding is used to connect wires and terminals to printed circuit boards, switches, and other electrical components. This ensures that the connections are strong, which is critical for ensuring the safe and efficient operation of these devices.
These contacts are typically made of a thin strip of metal that is welded to a thicker support material. The resistance welding process ensures a strong and consistent bond between the two materials, which is essential for reliable operation.
The types of welding used in aircraft vary from MIG welding to TIG but it also employs spot welding to assemble various metal parts, including airplane panels, engine components, and internal structures.
The aerospace industry is a highly specialized field that involves the design, development, manufacturing, and maintenance of aircraft, and their associated systems.
Aircraft panels are typically made of thin sheets of aluminum and must be joined together in a way that provides a strong and lightweight structure. Spot welding is ideal for this application, as it can create a high-strength bond between the metal sheets without adding excessive weight and cost.
HVAC ducting and the light industry are two important areas where the application of spot welding plays a significant role in the industry.
Manufacturing of ventilation ducting systems. Ventilation ducts are typically made of thin sheets of metal, such as galvanized steel or aluminum, that are joined together to form a network of channels for air to flow through.
The resulting seam is not only strong and leak-proof, helping to maintain the airflow efficiency of the system. Spot welding can also be used to join the metal frames and brackets that support the ductwork, ensuring a stable and secure installation.
Commonly used in the manufacturing of various metal products for the light industry. This includes products such as framing for the latest metal framed housing, shelving, storage racks, and metal electrical cabinets, as well as smaller items like brackets, hinges, and handles.
The production of metal furniture, such as chairs, tables, and Beds. Metal furniture is popular due to its durability and strength, and spot welding is an ideal process for rapidly joining metal components together.
Spot welding has also found its way into art, allowing artists to create intricate and unique metal sculptures and installations. Here are some examples of how spot welding applications are implemented by artists
Artists have created large metal sculptures made up of multiple smaller components that are spot welded together. To form metal installations for exhibitions and public spaces. These installations can range from small-scale wall art to large-scale public sculptures and architectural features.
Considerations For Where Is Spot Welding Used?
With each of the above use cases for resistance spot welding, a cost analysis will need to be conducted to see if it is the best welding process to implement. I have a few bullet points below for the pros and cons of pinch welds.
Advantages Of Resistance Spot Welding.
- Low heat-affected zone: can be used in applications of the latest steel alloys that are subject to becoming brittle if heat input is excessive.
- The process is very quick, joining metal pieces in just a few seconds.
- The spot weld process has minimal variation and is easily repeatable, for high-quality consistent welds.
- Relatively inexpensive compared to other welding techniques, requires minimal material and equipment
- Energy efficiency in production operations.
- The process relies on the workpieces to fuse together. A filler material or shielding gas is not required.
- The ability to weld a vast array of materials and alloys.
- Less Arc radiation. The stop welder electrodes clamp onto the metal reducing the visible arc.
- Fewer fumes than other welding processes with the elimination of shielding gases and any flux from welding electrodes.
- Minimal welding sparks, providing quicker cleaning of the welds, and minimal impact on assembly line infrastructure.
Disadvantages Of Resistance Spot Welding
- Not the best process to weld dissimilar metals together.
- Limited to lap or joint configurations.
- Not as strong as other types of welds, calculations on the number of welds to material thickness are required.
- Welding aluminum is only optimal when a specialized machine is employed.
- Harder for non-welding professionals to identify a poor weld.
- Weaker weld joint when dissimilar materials are used, due to individual melting points of the two materials.
- The initial cost of the portable medium-duty spot welders. This is only a factor for smaller collision repair facilities and the serious DIYer.
- An experienced welder needs to have a sound understanding of the machine to diagnose faults and correct them.
- Special surface preparation is required for some metals.
- Not ideal for thick sheet metal with multiple layers.
- Leaves a distorted weld nugget on the surface due to heat and pressure applied.
Industries That Benefit from resistance spot welding.
Resistance spot welding is a versatile and widely used process, including automotive, electrical, aerospace, manufacturing, and consumer goods. It offers several advantages, such as a low heat-affected zone, quick process, high-quality and consistent welds, and cost-effectiveness. From the assembly of vehicle bodies to the creation of intricate metal sculptures, resistance spot welding plays an essential role in many applications.
However, as with any welding process, cost and a suitability analysis must be conducted to determine whether it is the best welding technique for the specific application. I hope you now have a better understanding of where a spot welder can be used.