Permanent, Welded Connections
CADWELD connections are made with a semi-permanent graphite mold, which holds the conductors to be welded. Weld metal (a mixture of copper oxide and aluminum) is loaded into the top of the mold. The mold is covered and the weld metal ignited. The exothermic reaction produces molten copper, which produces a permanent, high conductivity connection.
Cathodic Protection Connections
- CADWELD connections are the accepted method of attaching cathodic protection cables to pipes (steel or cast iron), tanks and many other steel structures structures.
- CADWELD connections weld conductors to the object to be protected. Therefore, no galvanic corrosion can occur at the interface. With mechanical connections, surface contacts are present, which can corrode, resulting in an ineffective connection and current path.
- CADWELD connections for cathodic protection use a special alloy to provide minimum heat effect on the steel, especially important on thin wall, high stress pipes.
- CADWELD connections are also used for header cable taps, conductor splices and terminations, and ground rod connections.
A CADWELD Connection...
- Has current carrying capacity equal to that of the conductor.
- Is permanent aand cannot loosen or corrode to cause a high resistance connection.
- Uses lightweight, inexpensive equipment.
- Requires no external source of power or heat.
- Requires no special skills.
- Can be easily checked for quality.
CADWELD Welders and Molds
When making a CADWELD connection, an accurate control of the CADWELD process is accomplished by using a semi-permanent graphite mold. With the mold, control is exercised over the direction and speed of the molten CADWELD weld metal flow and final shape. The graphite used in a CADWELD mold is a high temperature type that lasts for an average of 50 to 100 CADWELD connections under normal usage.
Welder Price Key "CAA" is a solid graphite block with a hold-down handle used for horizontal welding. If a mold only is needed, (without handle), add an "M" to the end of the part number. Example: CAHAA-1G-M
Welder Price Keys CAT, CAP and CAN are split molds and use the Mini E-Z handle. All welders uder these price keys includes the handle or "mold frame".
Refer to the "Welder Price" column on the charts in the "Welder" tab on this page.
When making a CADWELD connection, be sure to use all proper PPE including eye protection, gloves and proper clothing. The CADWELD process is a "hot process" utilzing a molten compound and safety precautions are very important
CADWELD Exothermic Welding Manual