1. scope of application of cold welding repair machine:
cold welding repair machine is a professional precision repair welding equipment for pinholes, sand holes, air holes, cracks, bumps, scratches, pits, surface wear of mechanical parts, die wear and other small defects of castings. Widely used in mold industry, foundry industry, electrical appliance manufacturing industry, medical equipment, automobile, shipbuilding, boiler, construction, bridge construction and other industries.
2. Suitable material for cold welding repair machine:
The cold welding repair machine uses ordinary welding wire as the supplementary material, and the range of clamping welding wire is between 1.mm and 3.2mm.. The materials that can be repaired by welding are: gray, ductile iron, stainless steel, carbon steel, die steel, aluminum, aluminum alloy, and other conductive metals can be repaired.
3. Working principle of the cold welding repair machine:
(1) The principle of the cold welding repair machine is to use the charging capacitor to discharge in a period of 1/1 ~ 3/1 seconds and in an ultra-short time of 5/1 ~ 6/1 seconds, and the contact part between the electrode material and the workpiece will be instantly heated to 8℃ ~ 1℃, and the molten metal in the plasma state will be discharged. Because of the alloying with the base metal, it diffuses and infiltrates into the workpiece, forming a diffusion layer and obtaining a high-strength bond.
(2) principle of realizing cold welding (low heat input): why can cold welding be realized? Because the discharge time is very short compared with the next discharge interval, the machine has enough relative stop time, and the heat will spread to the outside through the basic body of the workpiece, so there will be no heat accumulation in the machined part of the workpiece. Although the temperature rise of the workpiece almost stays at room temperature, the temperature of the electrode tip can reach about 1℃ due to instantaneous melting.
(3) the bonding strength is high: when repairing and surfacing by using numerical control intelligent cold welding repairer, the heat input is low, so why is the bonding strength still high? This is because the welding wire instantly produces metal droplets and transits to the contact part with the base metal. At the same time, due to the high temperature of plasma arc, a strong diffusion layer like rooting is formed in the depth of the surface layer, showing high adhesion and will not fall off.
4. Repair characteristics of cold welding repair machine:
(1) Low temperature and normal temperature welding repair, no heat generation or thermal deformation of the matrix, no change in metallographic structure near the welding repair point, no stress, no crack and no hard spot hardening, and no influence on machining performance.
(2) the operation is simple, and one machine has multiple functions. In addition to surfacing repair function, it can also strengthen the surface coating of cemented carbide such as tungsten carbide.
(3) argon gas has good protective adhesion, high welding strength, metallurgical bonding, and solid, dense and non-dropping bonding after the filler and the matrix are melted at the same time. After welding repair, various mechanical processing such as turning, milling, planing and grinding can be carried out.
(4) The welding wire is widely available, economical and practical, and the whole machine is about 3KG, which can be repaired online.
(5) rotary self-destructive electrode deposition surfacing is easy to operate and has high working efficiency.
(6) Environmental protection and no pollution. No harmful gas is generated, and it can be directly held by hand, visually and accurately welded, with small welding repair points and small post-welding finishing amount.
(7) The welding repair process is repeated melting and accumulation of high-frequency welding repair points. No matter the size of the defect, it can be repaired wherever the pen tip can touch it.
(8) pure metal repair, no welding repair trace, welding repair effect meets the quality inspection standards.