The welding copper nozzle is a key component of the welding gun. It is responsible for conducting current, transporting the welding wire and stabilizing the arc. Its production process requires strict control of material purity and processing accuracy. Even an error of 0.1mm may affect the welding stability. The following is a breakdown of the standardized steps from raw materials to finished products based on the actual industrial production. Each link needs to take into account the thermal conductivity and structural strength of copper.
The first step is raw material screening and preprocessing. It is preferred to use T2 copper (copper content ≥99.9%) as the base material. This copper has high purity and good conductivity, and can reduce resistance heating during welding. First cut the copper rod into blanks with a diameter of 15-20mm and a length of 30-50mm (the specific size is determined by the welding gun model), and then use sandpaper to polish the surface of the blank to remove the oxide layer and oil stains - if the oxide layer remains, surface cracks will appear in subsequent processing, which will affect the sealing of the finished product.
The second step is preliminary forming processing. Use a CNC lathe to perform cylindrical cutting on the copper blank. First, carve out the main cylindrical structure of the copper nozzle, and then carve out the thread for connecting the welding gun at one end (usually M10 or M12 specifications, which need to match the welding gun interface). In this step, the cutting speed should be controlled at 800-1000r/min. If the speed is too fast, it will easily cause the copper blank to heat up and deform. If the speed is too slow, it will leave rough knife marks, which will require additional polishing later.

The third step is to drill the core tunnel. The center hole of the copper nozzle is the key to conveying the welding wire. A twist drill is required to drill a hole with a diameter that matches the welding wire (for example, for a copper nozzle suitable for 1.0mm welding wire, the hole diameter needs to be controlled at 1.05-1.1mm, leaving space for the welding wire to move). When drilling, the drill bit and the copper blank must be kept coaxial, and the deviation must be ≤0.05mm, otherwise the welding wire will get stuck during transportation, causing welding arc breakage.
The fourth step is surface treatment and strengthening. First put the copper nozzle into an ultrasonic cleaning machine, and use a neutral cleaning agent to remove the remaining copper chips and cutting fluid; then perform nickel plating - plating a 5-8μm thick layer of nickel on the surface of the copper nozzle can not only improve the wear resistance (to avoid the enlargement of the pores caused by long-term friction of the welding wire), but also prevent the copper from oxidizing and blackening, extending the service life. After nickel plating, it needs to be dried with hot air and the temperature is controlled at 80-100℃ to avoid the high temperature causing the coating to fall off.
The fifth step is accuracy testing. Use a micrometer to measure the outer diameter, hole diameter and length of the copper nozzle to ensure that the dimensions meet the requirements of the drawing; then use an air tightness tester to test the sealing of the hole - pass in 0.3MPa compressed air. If the air pressure does not drop within 5 minutes, it means that the hole is not blocked or leaking, and you can go to the next step; if the test fails, you need to return to the lathe and correct it again until it meets the standard.

The final step is inspection of the finished product before assembly. The copper nozzles are manually inspected one by one for thread integrity (no slip threads, missing teeth) and surface finish (no scratches, coating defects). Qualified finished products are packaged according to model and are waiting to be assembled with the welding gun. In the entire process, raw material purity, hole channel accuracy and surface coating are key control points, which directly determine the use effect and lifespan of the copper nozzle. Omissions in any link may lead to a decrease in welding quality.