| 摘要 |
<p>The filament is in the form of a cylinder of revolution (FR) and has at least one first set of layers (Cx-1, Cx...Cn) of spiral wound fibres (Fb) in a matrix, e.g. glass fibres in a polymerisable matrix, and with the fibres in at least two adjacent layers wound in opposite directions in coaxial spirals about the same axis (10). Tangents to the helices of spiral wound fibres form an angle of 44.6 degrees to the aforementioned axis. The cylindrical filament also has a central core (Ac) of a material having a low modulus of elasticity in torsion, and is preferably made with a protective sleeve (11) of an elastic or thermoplastic material.</p> |
