Steel plates generally come from two sources: steel mills and distributors. There are also various purchasing channels. When purchasing steel plates, pay attention to information such as the year of production, plate markings, furnace batch number, and whether there are material certificates. Ensure the steel plates are free of bubbles, cracks, and damage.

1. Check the supplier: First, check if the supplier is legitimate. Their sourcing channels should be clear. Some steel may be very cheap, but the quality is questionable. Choose a reputable supplier; don't just look at the price, but also pay attention to the quality of the steel plate.
2. Check the factory certificate: You need to see the manufacturer's factory certificate and steel plate acceptance certificate. Reputable factories can usually provide these. You can also request necessary material certificates from the supplier.
3. Check the contract: Next, check the contract between both parties. Specifications, models, production batches, and other details should be clearly stipulated in the contract. The contract is a strong bargaining chip if any problems arise during the acceptance of the steel plates.

1. Chemical method: Use pickling paste or spray to help repassivate the rusted parts and form a chromium oxide film to restore their corrosion resistance. After pickling, it is very important to rinse properly with water in order to remove all contaminants and acid residues. After all the processing is complete, repolish with polishing equipment and seal with polishing wax. For minor rust spots, you can use a 1:1 mixture of gasoline and engine oil to wipe them away with a clean cloth.

2. Mechanical methods: Sandblasting, shot peening with glass or ceramic particles, burr removal, brushing, and polishing. Mechanical methods may be used to remove contaminants caused by previously removed, polished, or buried materials. All kinds of contaminants, especially foreign iron particles, can become sources of corrosion, particularly in humid environments. Therefore, mechanical cleaning of surfaces should ideally be performed under dry conditions. Mechanical methods can only clean the surface and cannot change the material's inherent corrosion resistance. Therefore, it is recommended to repolish with polishing equipment after mechanical cleaning and seal with polishing wax.