Spreaders for lifting and unloading bundless of reinforcing bars are devices designed for lifting and unloading bundless of reinforcing bars, and may vary in type and design depending on the specific requirements of the lifting and site conditions.
Acommon type of spreader consists of a combination of four parts: the main wire rope, the shackle, the secondary wire rope and the fastening clamp. A single fastening fixture consists of two L-shaped hooks cut from 18mm steel plates and a 3.5t shackle. This kind of spreader is easy to operate and can effectively improve the efficiency of crane use, reduce labor input and lower the safety risk of lifting operation. In the process of using, the raw steel transportation vehicle first parked in the designated position, do inloading before the preparatory work; and then need to unload the upper part of the bundle of raw steel clamping fixture card tight grip; then the crane through the tightening fixture temporary bundles of raw steel in situ lifting uo to a certain height, the formation of the main steel wire rope through the gap; finally, the operator inserted wooden square, and in the reasonable lifting point with the main steel wire rope and the carabiner completed! The spreader is fixed before the rebar is formally lifted.
Another kind of spreader includes L-type fastening fixture, lifting buckle, main wire rope, secondary wire rope and other parts. Among them, the L-type fastening fixture is linked with the secondary wire rope, the lifting buckle is connected with the main wire rope, and the main wire rope and the secondary wire rope are connected with the hook of the crane. In addition, the spreader also includes a lifting and stretching mechanism, the lifting and stretching mechanism includes a flexible connector and a hook, the upper end of the flexible connector is connected to the lower part of the lugs, and the lower end is connected to the hook; at the same time, the upper part of the lugs has a lifting hole, the middle part of the lugs has a waist-shaped hole, and the connecting pins are set in the waist-shaped holes of the lugs, and can be moved up and down along the waist-shaped holes.
When the crane lifts the rebar, it usually uses a specialized spreader to ensure the safety and efficiency of the operation. A common type of spreader is a chain rigger with hooks specially designed to catch the links of the chain. These American-style big-bend or ramshorn-wing hooks are able to freely adjust the length range in which the chain is secured as needed. The other is a spreader for lifting rebar tendons, which consists of a lifting base, a multi-heeled lifting post fixed on the lifting base, two lifting lugs mounted on the lifting base, and a lifting rope connected to the two lifting lugs. Reinforcing bars of the same specification are set on the same lifting post and lifted by crane.
