| 摘要 |
A method of coating a field joint of a pipeline to accelerate the cycle time comprises positioning a mould tool around the field joint to define a mould cavity and injecting plastics material into the mould cavity through a plurality of gates in the mould tool, spaced along the mould cavity. The material is injected through different gates at different times as the mould cavity is filled, specifically through at least one first gate to advance a melt front within the mould cavity, and subsequently through at least one second gate spaced from the first gate, preferably when the melt front passes the second gate. First and second mould tools may be positioned successively around the field joint to create inner and outer coatings on the field joint. An insert may be positioned in the mould cavity to be embedded in the injected plastics material.
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