TUBE EXPANDING JIG FOR FINNED HEAT EXCHANGER

摘要

PURPOSE:To obtain a tube expanding jig for heat exchanger having fin that can expand required part simply and surely by fitting an elastic hose on the periphery of a hollow core tube, reinforcing it and fixing both end of the hose to the tube and supplying pressure liquid between the hose and core tube. CONSTITUTION:One end of a hollow core tube 2 is opened and fixed to a flare tube 3 for connecting a liquid pressure device. The other end is closed and a pressure penstration hole 4 is formed on the side wall. An elastic hose 5 such as rubber etc. is fitted on the outer periphery of the core tube 2 and the outer periphery of the elastic hose 5 is covered with a reinforcing member 6 such as plastics etc. leaving length A of tube expansion. The elastic hose 5 is stuck fast to the core tube 2 by pressing a holding part 7a on the reinforcing member 6, and a fixing part 7b is brazed to the end of the core tube to form a tube expanding jig 1. This jig 1 is inserted into the tube expanding part of the tube of a heat exchanger to be finned, and pressure liquid is sent into the clearance between the elastic hose 5 and core tube 2. The elastic hose is expanded to perform tube expansion and the fin is stuck fast to the outer periphery of the tube.