Drive in rack is composed of upright frames, Guide Rail beam, top beam, back beam, top brace, back brace and so on. This kind of rack is suitable for the storage mode with relatively few varieties and integral whole. Because the forklift truck can drive into the storage area only by arranging the aisle, the warehouse utilization rate is high, and it is mostly used in cold chain logistics, beverages, food, dairy products and other fields.
Drive in rack system has the typical characteristics of FILO. Forklift trucks are usually operated in the mode of continuous “lifting and hitting” with a high center of gravity after lifting. Forklift trucks are prone to sway into the racks with the unevenness of the ground in the corridor, which will affect the stability and safety of the rack structure. The technical requirements are relatively high, and the turnover speed and efficiency of goods are also affected to a certain extent.
The structure design of the drive in racks is the key factor to determine the quality of the racks. In addition, the material, production technology, production equipment, fixtures and powder coating, etc. will directly affect the quality and grade of the racks. The main structure of the rack is a space steel structure. It is very complicated to calculate its strength, stiffness and stability by the traditional classical mechanics method or dynamic method. Simplified calculation model can be used to analyze and optimize the structure in combination with domestic and foreign standards and test data. At present, most of the finite element structural strength analysis and stability analysis are used for auxiliary design and full-scale load test verification.
In order to ensure its stability, the slenderness ratio of uprights should not be too high. Generally, it should be controlled within 10 meters and more than 4 layers and 3 to 5 rows. Compared with the same kind of pallet racks, in addition to the steel section specifications to be larger, but also need to install tensile fasteners. The main fittings of the drive in rack include frame, top beam, top bracing, back bracing, guide rail, upright protector or frame protector and so on.
In the design process of the drive in rack, first of all, the standardization of the pallet unit should be carried out to determine the size, stack height and rated load of the pallet. Then the overall structure of the drive in rack and the key dimensions of the storage unit, such as span, depth, spacing and height, can be planned to carry out the structure and components of the rack. In design, the key parameters should be verified by design or test, the simplified mechanical model should be established according to the case structure, and the strength, stiffness and stability should be set up according to the actual force (including seismic load) and load distribution of the rack, and the geometric parameters and mass characteristics of the corresponding components. If necessary, can be verified through experiments to ensure that the design results are in line with the actual situation.