| 摘要 |
PURPOSE:To improve the heat transfer efficiency by forming a heat transfer pipe of a heat exchanger with a plastics pipe, on inside surface thereof a hydrophilic layer is formed. CONSTITUTION:A polyester film tape 1 having a thickness less than 0.1mm. is slantingly and endlessly wound as overlapping one portion of the tape, and the overlapped portion is welded with a thermosetting polyester family adhensive, then a cylindrical pipe 2 is formed. The pipe 2 formed by said process is cut at a required dimension, inserted into a side plate 4 made of plastics which is provided with through holes 3 in equal interval, then adhered with said side plate 4, thus, a heat exchanger is structured. A contact angle between the pipe 2 and the water is 65-70 deg. in forward contact angle, 48-50 deg. in backward contact angle. A hydrophilic layer 5 is formed by the corona discharge treatment, or by coating of such hydrophilic agent as a water glass and the like. Consequently, the water drops 6 adhered on the inside wall of the pipe 2 becomes especially small, accordingly, the moistue condensation effect is improved, the heat exchange efficiency is also improved. |
