An automatic unlock system of hot steel thermal conveyor carriage is designed, hidden problems such as car is driven when door is open or door is unexpected open when car is running are resolved.

Based on the production line of color coating in Tangshan Iron and Steel Corporation, the principle and implementation of automatic resetting and coil transferring for carriage are described in brief.

Stainless steel screw, hex bolt series: tighten screw, machine screw, nail screw, self-tapping screw, expansion bolts, carriage, lifting eyebolt, a tooth, flat mat, play split cotters cushion etc.