| 摘要 |
<p>The pressure medium used to expand a zone of a thermoplastic pipe section into a cavity in the mould wall outside the pipe, so as to form an internal circumferential groove is a deformable, thermoplastic, elastomeric base material. This forms the sealing ring to be inserted into the groove, and it is brought to the correct shape and stabilised. The pipe section is produced by means of a mould with an approx. tubular modular cavity, which is filled with plastic material. An annular cavity is then produced in the mould on the outside of the pipe section, and opposite, this, inside the pipe, the pressurised medium is applied. Used to reduce the production time necessary for the forming of the internal groove and the fitting of the elastic sealing ring.</p> |
