Thermoplastic or elastomeric extruded sheathing - for cables etc., with cross linking or vulcanisation taking place during extrusion and accompanied by impact forces

摘要

The impact forces and/or rotational forces applied to the material as it passes through the extruder head is applied at a variable frequency, the die accommodating a ring shaped push rod which reciprocates axially and pref. also has a rotational movement. Cross - linking is intensive and retention at vulcanising temps. minimal and independent of the thickness of the sheathing produced. Good mechanical strength is obtd. Pref. at the higher frequency levels the impact motion has a lower energy content and is reversed.