摘要 |
A hose or pipe comprising a tubular layer formed by helically winding plastics material and/or rubber around a mandrel reinforced with a high tensile spring steel wire which is formed into a helix around and simultaneously with the winding of the tubular layer by positively driving the wire into engagement with coil-forming means, disposed around the tubular layer, which gives the wire a set and produces a wire helix having an internal diameter approximating the external diameter of the tubular layer, the wire being driven into the coil-forming means at a linear speed substantially equal to the speed of the surface of the helical path around the tubular layer against which the wire coil is to lie.
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