| 摘要 |
<p>A generally annular friction lining for a coupling or brake is formed by extruding a paste contg. (a) a liquid, hardenable binder, and (b) a fibrous filler in the form of separate strands, through a mould of such dimensions that most of the fibres are oriented in the direction of the length of the extrudate, and coiling the extrudate spirally to give a pre-moulded article in which the fibres are tangential to the radius of the disc-shaped article. The pre-moulded article is then pressed and hardened. Claimed binders are phenol-HCHO and melamine-HCHO resins. The resins may be used in soln., e.g. in (m)ethanol, isopropanol or acetone; the pre-moulded article is then left to stand at 20-25 degrees to facilitate evapn. of the solvent. Asbestos fibres are pref. esp. those of Canadian classification 6D, 7D or 5R. The length of the majority of the fibres is is not >1.27 cm (0.32-1.27 cm). Other suitable fibres include those of glass, rock wool, raw cotton, steel wool, sisal, C and non-ferrous metals. Shorter fibres can be used in known processes. The complete impregnation of the fibres is easier. The friction lining has high bursting strength.</p> |
