Part of the contents of "YB/T 5055-2014 Crane Rail" are as follows:
Scope
This standard specifies the size, shape, weight and allowable deviation, technical requirements, test methods, inspection rules, marking, packaging, transportation, storage, etc. of crane rails. This standard applies to special section rails for crane trolley and trolley tracks.
Dimensions, shape and allowable deviation
Length: The standard length of the rail is 9m, 9.5m, 10m, 10.5m, 11m, 11.5m, 12m, 12.5m. With the agreement between the supplier and the buyer and specified in the contract, a certain proportion of irregular length rails with a length of 4m to 8.9m can be supplied, but the weight is calculated by 100mm. The allowable deviation of the rail length is + 500mm.
Bending: The lateral bending of the rail shall not exceed 1.5mm per meter, and the total bending shall not exceed 8mm. The total bending of the rail in the upper and lower directions shall not exceed 6mm. The bending of the rail end shall not exceed 1mm within 0.5m. Due to the capacity limitation of the straightening equipment, the bending of the QU120 crane rail is agreed by the supplier and the buyer.
Torsion: The torsion of the rail shall not exceed 1/10000 of the total length of the rail.
Cross-sectional asymmetry: The asymmetry between the cross-sectional area of the rail and the vertical axis shall not exceed 2mm at the bottom of the rail and 0.6mm at the head of the rail.
Grade and chemical composition
The grade of the crane rail is U71Mn, and its chemical composition (melting analysis) shall comply with the regulations, with a C content of 0.65% to 0.76%, a Si content of 0.15% to 0.58%, a Mn content of 1.10% to 1.40%, a P content of ≤0.035%, and a S content of ≤0.030%.
Mechanical properties
The tensile strength of the rail shall not be less than 90kg/mm² (883MPa).
Surface quality
Indentations, pits and scratches with a depth not greater than the allowable negative deviation value of the rail size and hairlines with a depth not greater than 1mm are allowed.
Technical requirements
Metallurgical method: The rail is made of killed steel smelted in an open-hearth furnace, converter or electric furnace. The production process that does not produce white spots in the rails should be adopted.
Surface quality:
There shall be no cracks, folds, scars, bubbles and inclusions on the rail surface. Indentations, pits and scratches with a depth not greater than the allowable negative deviation of the rail size and hairlines with a depth not greater than 1mm are allowed.
There shall be no cracks, delamination and shrinkage residues on the rail end face.
The rail end face should be cut straight, and the end face skewness shall not exceed 5mm in any direction. The rail surface defects are allowed to be cleaned longitudinally with a pneumatic shovel, and the cleaning depth (calculated on one side) shall not exceed the allowable negative deviation of the size. Welding or filling of rail surface defects is not allowed.
Test method
The sampling quantity, location and test method of each batch of rails shall comply with relevant regulations. For example, chemical composition analysis is carried out in accordance with a series of standards such as GB/T 222, GB/T 223.11, GB/T 223.12, etc.; tensile test is carried out in accordance with the provisions of GB/T 228.1, and transverse specimens are taken, one each from the rail head and rail bottom.
Inspection rules
Inspection and acceptance: The inspection and acceptance of rails shall be carried out by the supplier's technical supervision department, and the buyer has the right to conduct inspections in accordance with the provisions of this standard.
Batch rules: Rails shall be inspected in batches, and each batch shall consist of rails of the same brand, furnace number, specification, and delivery status.
Marking, packaging, transportation, storage
Marking: On the waist of each rail, there is a raised mark every 4m, including the manufacturer, model, brand, year and month of manufacture (last two digits), and furnace number.
Packaging: The packaging of rails shall comply with relevant regulations to prevent damage during transportation and storage.
Transportation: Appropriate measures should be taken during transportation to prevent rail deformation, damage and corrosion.
Storage: Rails should be stored in a dry, well-ventilated place to avoid moisture and corrosion.