Maintenance and Adjustment about Square Bar Crane Rail
The square bar crane rail for the crane and the trolley to travel vertically and horizontally is the basis for the good operation of the crane. Besides the quality of the square bar crane rail itself, the installation quality of the square bar crane rail is the basic condition for ensuring the smooth operation of the crane. Cranes, especially double-girder overhead cranes used in workshops, have been used for many years, and various problems often occur in the rail, such as loose rail joint splint, track wear, track displacement, deformation, and parallelism of the amount of track parallelism, plant subsidence, etc. The orbital flatness is out of tolerance. These problems have a great impact on the operation of the bridge crane. Usually, rail gnawing will occur for the bridge crane during operation, abnormal noise will be generated during operation, and the walking wheels of the large and small vehicles will be eccentric, and the tread of the crane wheel will not be touched. This phenomenon often causes the swaying of the crane, which will cause unstable operation. Unstable operation is not obvious with the heavy load, but the operation is especially abnormal with ligh load. With the square bar crane rail that meets the requirements of the standard specification as a support, some problems in the operation of the crane will be solved.
The standard is used to determine the deviation of the dimensions resulting from the assembly of the crane and its square bar crane rail during the new installation, modification, reassembly or repair of the assembled crane before the crane is put into operation. This applies to newly installed or serviced cranes and their rails. This magnitude can be expressed either by the absolute value of the extreme dimensional deviation or by the geometric tolerance. The span refers to the distance between two parallel tracks on which the crane walks. The span of the crane is generally 1.5m smaller than the span of the workshop, and its span is one level every 3 meters. The lateral curvature of the rail is ≤1.5 mm per meter and the total bending is ≤8 mm. The total bending of the rail in the upper and lower directions should be ≤6mm. The end of the rail should be ≤1mm within 0.5m. For crane rails due to the ability of the straightening equipment, the degree of curvature should be agreed by the supplier and the buyer. The rail torsion shall not be greater than 1/10000 of the total length of the square bar crane rail. The symmetry of the rail cross section and the vertical axis, the bottom of the rail should be ≤ 2mm, and the rail head should be ≤ 0.6mm. The bottom of the rail should not be recessed. The center of the bottom of the rail should be ≤0.5mm from the two sides. The longitudinal inclination should also meet the tolerance standards of the wheel and the cart and trolley. There should be no cracks in the square bar crane rail. The wear of the rail top and the side of the rail head should be <3mm. For the crane rails used in the workshop, the joints are not recommended for welding because of the inconvenience of adjustment and maintenance, especially the wear of some parts of the rail. It is even more difficult to be replaced after the tolerance. It is also appropriate to use a connecting platen and a bolt to connect the rail joint. If a section of rail deformation and tolerance is encountered and it is not easy to update, the piece is repaired by thermal correction. Correction treatment is recommended when the lateral bending of the rail is >10 mm. At this point, the rail should be unloaded from the road beam to the ground and the rail floor placed freely. We should check if the connecting bolts are loose or come off, and the connecting plate and the pad have no odor, defects or falling off. We should also check the weld for cracks. For new rails, the corresponding position offset of the two rail joints should be >600mm.
The crane rail is a key component of the crane stability. The adjustment method is also different due to the actual situation. Paying much attention to the maintenance of the crane rail and can reduce the occurrence of many crane failures. The crane rails always according to the standard requirements not only can assist the crane to run stably, but also extend the service life of the crane wheels.
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