| 摘要 |
PCT No. PCT/SE89/00654 Sec. 371 Date Jul. 3, 1990 Sec. 102(e) Date Jul. 3, 1990 PCT Filed Nov. 14, 1989 PCT Pub. No. WO90/05625 PCT Pub. Date May 31, 1990.A method for temperature conditioning a blank of plastic material in which a conditioning mandrel is placed within the blank and thereafter expanded into reliable abutment against the inner surface of the blank. The mandrel is thereafter returned to its initial position. The outer surface of the mandrel is adjusted to and maintained at a certain temperature, whereby, during the abutment, an energy exchange takes place between the blank and the mandrel for adjusting the temperature of the blank. At high temperatures of the mandrel, the mandrel is displaced out of the blank after such short time that the plastic material in the region of the abutment surface never passes the critical temperature of tackiness of the plastic material and/or thermal crystallization of the plastic material. As a rule, the expansion and contraction of the mandrel is repeated one or more times.
|
