| 摘要 |
<p>Thermoplastics material is blow moulded by a method which includes the steps of forming a tubular parison and as mould parts 40 are closing around the parison moving a blow pin 30 forward. Air at a pressure of 10 bar is blown through the pin 30 to deform an outer skin 41 of the thermoplastics material as the mould parts are closing. The pin 30 is then inserted through the skin 41 and an article such as a case is blow moulded. The pin 30 has a blunt tip 31 and a tubular sleeve 41c forms around the pin 30 as the pin 30 is operated to sleeve the pin 30 This prevents leak-back of air and allows a greater pressure blow moulding at higher cycle times and with improved surface finish. <IMAGE></p> |
