Chain rigging is wear-resistant, heat-resistant, has low ductility, and will not elongate under stress. It has excellent applications in multiple lifting and hoisting fields. Below, we will introduce a flash butt welding process for chain rigging.

The principle of flash butt welding is to use a butt welding machine to make contact between the two ends of the metal. After the metal is heated to a certain temperature and softened, it is subjected to axial pressure forging to form a butt welded joint. There are three types of specific subdivisions.

1. Continuous flash welding

The process of continuous flash butt welding includes: continuous flash and top forging process. When welding, first close the circuit to make slight contact between the end faces of the two steel bars. At this time, sparks of melted metal particles - flash - will be sprayed from the gap between the end faces. Then slowly move the steel bars to maintain slight contact between the two end faces, forming a connection flash. When the flash reaches the predetermined length and heats the end of the steel bar to near the melting point, forging is quickly carried out with a certain pressure. First, perform electric forging, then use electric forging to a certain length, and the welded joint is completed.

2. Preheating flash welding

Preheating flash welding is an additional preheating process before continuous flash welding to expand the welding heat affected zone. The process includes preheating, flashing, and forging. When welding, first turn on the power supply, and then alternate the contact and separation of the two steel bar end faces. At this time, intermittent flashes of light are emitted in the gap between the steel bar end faces, forming a preheating process. When the steel bars reach the preheating temperature, they enter the flashing stage and are subsequently forged.

3. Flash Preheating Flash Welding

Flash preheating flash welding is a process of adding a flash before preheating flash welding, with the aim of making the uneven steel end face burn flat and ensuring uniform preheating. The process includes: primary flash, preheating, secondary flash, and forging process. During welding, the first step is to flash continuously to flatten the end of the steel bar, followed by preheating flash welding.