PURPOSE: To obtain a method of easily manufacturing a hollow body and at the same time freely controlling the wall thickness of the hollow body by a method wherein a sheet having an ultra-high-molecular-weight polyethylene layer and a material with a thermal expansion coefficient smaller than that of ultra-high-molecular-weight polyethylene are wound round a heat resisting core, integrally welded by heating and, after cooling, the heat resisting core is removed.
CONSTITUTION: A sheet having at least an ultra-high-molecular-weight polyethylene layer is wound round a heat resisting core. In addition, a heat resisting material, the thermal expansion coefficient of which is smaller than that of ultra-high-molecular-weight polyethylene, is wound onto the outer periphery of said sheet so as to integrally thermoweld the sheet having an ultra-high-molecular-weight polyethylene layer to itself at a temperature exceeding the melting point of ultra-high-molecular-weight polyethylene, preferably a temperature within the range of about 140W280°C under the state that both terminals of the material are fixed. Any temperature, which is below the melding point of ultra-high-molecular-weight polyethylene and within which no thermal decomposition of ultra-high-molecular-weight polyethylene occurs, will do as its heating temperature. By taking the thermal deterioration during heating into consideration, the especially favorable heating temperature is 250°C or below. A pipe consisting of the integrally formed sheet having an ultra-high-molecular-weight polyethylene layer is cooled down and, after that, the wound heat resisting material is unwound and finally the obtained formed pipe is removed from the heat resisting core.
IKEUCHI AIJI
YOKOYAMA SHIGEKI
NOGUCHI YASUO
NIPPON PETROCHEMICALS CO LTD
| JPS5382882A | 1978-07-21 | |||
| JPS60155428A | 1985-08-15 | |||
| JPS56161145A | 1981-12-11 | |||
| JPS6046215A | 1985-03-13 |