It is composed of six systems: door body, guide rail, counterweight, sealing, transmission, power, etc. According to the size of the opening, it is determined that several door panels constitute a lift door, that is, “N” block lift doors. The counterweight is usually used to achieve balance. The counterweight track is equipped to operate safety and reliably through the door opener. The characterized is low failure rate and can realize multi-block linkage, electric, manual, automatic control., etc. The heavy-duty which uses dynamic balancing method, which saves space for counterweight. .The working principle is: the wire rope is wound in dynamic and static pulleys, and the door opening and closing movement is realized by chain transmission and pulley transmission, so that each door panel runs at a different transmission ratio speed, and finally reaches the opening and closing doors at the same time.

The door is designed with a steel structure. When it is not a daylighting structure, can adopt the polyurethane panels and new insulation materials; When daylighting is required, use a solar panel or a new material with good insulation and light transmission properties; the track is composed of multiple grooves ; The sealing material adopts EPDM rubber and industrial brush, with the characteristics of low temperature resistance, weather resistance, flatness and smoothness, and good elasticity. The transmission pulley and sprocket are made of high-quality carbon steel and heat-treated.