Such joint of metal parts at which between them interatomic connection is established, as a rule, at local heating is called welded. One of types of welding – dot. Spot welding demands availability of welding machine or special welding pincers. It is possible to make the device for spot welding if desired the hands.
It is required to you
- Spot welder
1. Before starting creation of the unit for spot welding, understand for yourself that it has to be rather powerful and easy-to-work. The good unit allows to combine qualitative sheet steel up to 3 mm thick.
2. One of the main constructive parts of the unit for welding – the basic transformer. Use as the transformer the serial device, for example, of OSM-1. Leave the primary winding of the transformer without changes, it has to contain 200 rounds of wire of PEV2-1.9. Replace secondary winding with more powerful, having used for it electrical wire of PVZ-50. The secondary winding has to consist of two three-turn shares with the general section of 100 quarter of mm.
3. Adjustment of size of current in the unit is not obligatory. During welding be guided by time of heating and control visually (on coloring) or by means of time relay with endurance range up to 5 pages.
4. Holders of electrodes execute from dural rod with a diameter about 30 mm. Make the lower electrode motionless and isolate from cheeks and fastening bolts washers from textolite or adhesive tape on cotton basis. Pick up spot welding electrodes copper, with a diameter of 12 mm. Fix electrodes in holders by means of brass washer and two bolts.
5. In starting position holders with electrodes part with spring (for example, from unnecessary "folding bed"). At the same time trace that the spring did not lead to short circuit on conclusions of secondary winding during the operation of the transformer. The possible decision is to use the plastic sleeve, having attached it to face of the motionless holder the screw.
6. Connect the welding machine to network via the time cut-out calculated on 20 A. For control of the unit use the magnetic actuator which has to turn on pedal, it is desirable with key in the form of "fungus". Ground secondary winding and the body of the transformer.
7. For welding of parts clamp them in electrodes of the welding unit. After that between electrodes the current warming metal in the place of contact up to the metal melting temperature will proceed. After that current is disconnected and peculiar pro-forging by increase in force of compression of electrodes is made. At compression of electrodes, metal crystallizes, the welded joint is formed.