heat exchanger Expander is designed to push a "bullet" through the tubing of a coil which expands the tubing and creates an interference fit with the fin holes. All tubes are expanded at the same time. Near the bottom of the ram stroke, final expanders will be pushed into the bullet expanded open ends of each tube. This final expansion provides the necessary cup or bell for the return bend to seat into the brazing. It is special equipment which used to expand fin type heat exchangers . And it could finish expanding, flaring and folding edge at one cycle. ①Model :YZL1000 (Max. coil length 1000mm)、YZL1200 The oil cylinder for expanding tube is arranged on the top of expanding bar, which is mainly used to mass produce family air conditioners. ②Model:YZL1600、YZL2000、YZL2500 The oil cylinder for expanding tube is arranged inside of machine body. The expanding power is transferred by transferring rack to lower theheight of machine, which is normal used to expand central air conditioners.