When using galvanized steel pallets in a low-temperature cold storage environment, we must first pay attention to the performance changes of the steel itself at low temperatures. Ordinary steel will experience "cold brittleness" in a low-temperature environment, that is, as the temperature decreases, the toughness and ductility of the steel decrease, the brittleness increases, and it is easy to break. Although the surface of the galvanized steel pallet is covered with a zinc layer, the cold brittleness problem of the internal steel still exists. When the temperature of the cold storage is as low as -20℃ or even lower, if the pallet material is not specially treated, it may cause cracks in the pallet frame and supporting structure when it is hit or impacted during transportation, affecting the safety of use. Therefore, the galvanized steel pallet used in low-temperature cold storage should use steel with good low-temperature toughness, such as alloy steel with added alloy elements such as nickel and manganese, to improve its ability to resist brittle fracture in a low-temperature environment.
The low-temperature resistance of the galvanized layer is also a key consideration. Although the galvanizing process can effectively improve the corrosion resistance of steel pallets, the physical properties of the galvanized layer will change in a low-temperature environment. Low temperature may cause the zinc layer to shrink. If the bonding strength between the galvanized layer and the steel substrate is insufficient, the zinc layer is prone to cracking and peeling, exposing the internal steel to a humid environment and accelerating corrosion. The hot-dip galvanized layer is relatively thick and tightly bonded to the steel. It is more stable at low temperatures than the cold-dip galvanized layer, but attention should still be paid to the uniformity and density of the zinc layer. In addition, if there is a defrosting operation in the cold storage, the alternation of hot and cold will cause the galvanized layer to repeatedly expand and contract, further increasing the risk of damage to the zinc layer. Therefore, when choosing a galvanized steel pallet, it is necessary to ensure that the thickness of the galvanized layer meets the standard (the thickness of the hot-dip galvanized layer is generally not less than 80μm), and check the integrity of the zinc layer regularly during use.
The humidity in the low-temperature cold storage is high, and water vapor is easy to condense into frost or water droplets on the surface of the pallet, accelerating the corrosion of the pallet. In addition to the protection of the galvanized layer, the pallet needs to be treated with additional moisture-proof treatment. A low-temperature resistant anti-corrosion coating, such as polyurethane coating or epoxy resin coating, can be sprayed on the surface of the galvanized steel pallet to form an additional protective barrier. These coatings can still maintain good flexibility and adhesion at low temperatures, effectively isolating water vapor from contacting steel. At the same time, the structural design of the pallet also needs to consider drainage issues to avoid residual water accumulation. For example, a hollow or grid-shaped bearing surface design is used to allow condensed water to drip in time; drainage holes are set at the bottom of the pallet to ensure that the accumulated water is quickly discharged and reduce the contact time between the pallet and the water.
In cold storage operations, frequent forklift handling and stacking operations place higher requirements on the structural strength and stability of galvanized steel pallets. Low temperatures can make steel brittle. If the pallet structure is not designed reasonably, it is easy to break at the stress-concentrated parts. Therefore, it is necessary to strengthen the key stress-bearing parts of the pallet, such as corners, edges and supporting beams. Thickened steel plates, additional reinforcement ribs or welding reinforcement can be used to improve the overall rigidity and deformation resistance of the pallet. In addition, the connection parts of the pallet, such as welding points and bolted joints, may become loose due to material shrinkage at low temperatures, and need to be regularly inspected and tightened to prevent damage to the pallet due to connection failure.
Low temperature environment will also affect the friction between pallets and goods, and between pallets and shelves. When the temperature drops, the surface of the pallet may become smooth due to frost, and the goods may slide easily, posing a risk of falling; during the storage and retrieval process of the shelf, the pallet may also shift due to insufficient friction, affecting storage safety. To solve this problem, anti-slip design can be added to the surface of the pallet, such as laying rubber anti-slip mats, setting anti-slip convex patterns, or using rough surface treatment technology. At the same time, choose a suitable cargo fixing method, such as using wrapping film, straps, etc. to firmly fix the goods on the pallet to ensure that the goods and the pallet remain stable in a low temperature environment.
Equipment and tools in low-temperature cold storage, such as forklift forks and shelf support surfaces, will also change in size at low temperatures, which requires that the dimensional accuracy of the galvanized steel pallet must strictly meet the standards. If the size deviation of the pallet is too large, it may not be inserted or removed smoothly during storage and retrieval of the shelf, and may even cause jamming and collision accidents. Therefore, when customizing or purchasing galvanized steel pallets, the dimensions must be matched with the shelf system and handling equipment of the cold storage to ensure that the length, width, height and fork hole dimensions of the pallet meet the requirements of cold storage operations. At the same time, considering the shrinkage effect of steel at low temperatures, the pallet size design can reserve a certain tolerance range to ensure normal use in low temperature environments.
In terms of daily use and maintenance, a special maintenance system for low-temperature cold storage environments needs to be established. Operators should avoid using sharp tools to collide with pallets to prevent damage to the galvanized layer; regularly clean frost and debris on the surface of the pallet to keep the pallet clean and dry; conduct a comprehensive inspection of the pallet at regular intervals, focusing on the condition of the galvanized layer, structural parts, and connection parts, and repair or replace problems in a timely manner. In addition, if the pallet is idle for a long time, it should be stored in a normal temperature environment to avoid the degradation of material performance due to long-term exposure to low temperatures and extend the overall service life of the pallet.
