Lift the nose wheel and bottom wheel shaft installation errors likely to cause the hopper with a deviation, the main manifestations are: head round and bottom round of the drive shaft without parallel in the same vertical plane; two drive shafts are mounted in a horizontal position and not in the same vertical plane; two parallel drive shafts, not the level in the same vertical plane.
The above situation, the hopper with a deviation could easily cause a crash hopper and barrel, hopper with a tear. Also hoist head to withstand greater dynamic pressure, up to 100 tons, due to the inevitable emergence of long-term operation in the squeeze bearing bit worn.
Traditional methods to brush after machining or welding repair, but there are some drawbacks both: high temperature welding thermal stress generated can not be completely eliminated, could easily lead to material damage, leading members appear bent or broken; and painted by brush plating layer thickness restrictions, easy to peel off, and the above two methods are used to repair metal metal, you can not change the "hard-on-hard" with the relationship, under the combined effect of all forces, will cause wear again.
In response to these problems, major European companies are using a method of repairing a polymer composite material, which is the most mature of the United States is the world blessing blue technology system. Polymer material with superior adhesion, excellent mechanical properties, can avoid demolition of Free machining. Neither welding thermal stress on the repair thickness is not limited, while products with metallic materials do not have a concession, can absorb impact shock hoist, to avoid further possibility of wear, and greatly extend the life of equipment components, save a lot of down time, creating significant economic value.