摘要 |
For use in the manufacture of reinforcement layers for flexible pipes which are capable of absorbing compressive or tensile forces, and which are used for the transport of oil and gas, a thermoplastic material is applied to a strength-imparting layer. The strength-imparting layers are reeled on reels, and following unreeling they are laminated by application of heat and in direct continuation applied to the flexible pipe. The strength-imparting layer expediently consists of a polymer which is reinforced with at least 20% by volume of fibres. The thermoplastic material is of a reversible type, i.e. it may change from being relatively soft, but non-sticky to being sticky by changes in temperature. The use of the method according to the invention allows manufacture of very strong reinforcements for flexible pipes which cannot be manufactured using a solid material, such as steel, since high preforming bending forces are required in the shaping. In addition, a reinforcement element is provided which is capable of resisting instantaneous shock loads as the thermoplastic material is protective.
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