1, hose-type connection: mainly used for duct and parts (such as radiator, static pressure box side of the outlet, etc.) connected. When installed, the hose is set at both ends of the tube, and then the hose is tightened with a special soft card.

     2, plug-type connection: mainly for rectangular duct connection. Insert different types of cuttings into the ducts and compaction.

     3, hoop type connection: mainly for steel plate ventilation ducts and spiral duct connection, the first of each pipe section of the two ends rolling out the drum, and to one end of the small mouth. Install the airflow direction when the small mouth into the big mouth, outside with a steel hoop to the two ends of the drum hoop tightly connected, and finally with the bolt in the middle of the earrings fixed tightening.

     4, plug-in connection: mainly for rectangular or circular duct connection. First make the connection pipe, and then insert the two sides of the duct, and then pull the rivet to close it.