What is CAD Welding ( Exothermic welding) ? Definition, Types & Benefits

CAD welding is another name for the exothermic welding technique. This technique is utilized when you have to make strong bonds on those metals that cannot withstand the hotness of arc welding. Moreover, the exothermic welding process is not well known among the masses because its major application is to weld large electrical cables of copper and aluminum.

The thing to notice about CAD welds is they are very strong; that’s why electrical lines endure long. A significant advantage of CAD welding over other welding techniques is it does not decrease the conductivity type of the joints. Copper is a sort of metal that gets hit in its conductivity capability when it gets mixed with other metals.

Related: TIG welding of copper 


How to perform CAD welds?

This process is named as an exothermic welding process, so the earth conductors are perfectly connected with each other. To join uneven metals, this process is also very handy. Most importantly, this technique does not require an outward heart source, rather than that it works by utilizing an exothermic chemical reaction.

Making an exothermic weld is very simple as it involves molding, welding powder, handling clamps, and CAD welder. Apart from that, the connections made are highly resistive to corrosion, have excellent conductivity, and resist recurrent fault current.


How to create an exothermic connection?

Creating an exothermic weld is very easy if you follow the below-given steps:

  1. After drying, place the clean conductors on the exothermic mold. You can achieve that by preheating.
  2. Ensure that the position of the metal retaining disk and the handling clamp is at the base of the exothermic vertex mold.
  3. Now, put the welding power on the mold and make sure that you are applying it properly.
  4. Use a flint gun to spark the initial powder
  5. For stabilizing before opening the mold, wait for a while and let their exothermic reaction take place.
  6. Clean the seal, weld wipe mold properly before making the next connection.

What are CAD welding types and uses?

Types of CAD welds:

There are typically two types of CAD welds:

  • Rail welding
  • Cadweld

Uses of CAD welding:

The use of CAD welding is in the following areas:

  • Galvanized cables
  • Electronics and its equipment
  • Copper

What are the advantages and disadvantages of CAD welding?


  • It does not demand spending too much time to master this skill
  • Most of the time it comes with pre-packaged thermite
  • Everlasting connections
  • Enhanced connectivity of cables and wires


  • Some environmental conditions do not suit this technique
  • It can be very dangerous, which depends on the applications


Q.1 Do CADweld shots expire?

Ans: Basically, the CADweld shot is a pre-packaged filler that is put into the mold. The shots will never expire if you follow the manufacturer’s recommended procedure.

Q.2 Is it okay to CAD weld in the rain?

Ans: We don’t suggest you do CADweld in the rain as there will be a chance that the rainwater may go inside the chamber. But if you still want to make CAD welds, then make sure that the weld’s surrounding area must be dry.

Q.3 What is the temperature of CAD welding?

Ans: The temperature necessary to make CAD welds is 4000 degrees Fahrenheit. Moreover, this temperature is 7000 degrees Fahrenheit, less than I had expected. But it is still very hot to make welds.