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Commonly used sandwich panel classification:

　　 1. Machine-made sandwich panels (core materials include: polystyrene, rock wool, paper honeycomb, glass wool, polyurethane).

　　 2. Hand-made sandwich panels (core materials include: rock wool, glass magnesium, paper honeycomb, aluminum honeycomb, glass wool).

　　 3. Electrolytic steel plate (single-layer steel plate for wall keel).

Compared with manual sandwich panels:

　　1. Machine-made sandwich panels, ordinary steel plates have a single plate type, and manual sandwich panels have 8-9 different plate types to meet the needs of different projects

　　2. Appearance: The flatness of the machine-made sandwich panel and the product insertion seam are not as fine as the manual panel.

　　3. Strength: Machine-made sandwich panels generally have poor strength, especially rock wool panels. The hand-made panels have cold-formed steel plates at the edge banding. Change the steel plate insertion method to increase the strength.

　　4. Fire protection: With the continuous improvement of fire protection requirements, the mechanism of sandwich panels has been difficult to meet the engineering needs. The foam board market is gradually shrinking and replaced by hand-made sandwich panels that can reach the corresponding fire resistance limit.