Research and development of a novel convection moulding process and butt fusion pipe pup jointing system capable of producing large diameter (630mm to 2500mm) high density polyethylene pipe fittings of various designs and profiles

该公司正在研究和开发一种新的对流成型工艺和管道接头技术，以开发一系列直径在630毫米到2500毫米之间的聚乙烯管件型材（等三通、弯头、减速管和端盖）。目前最先进的大直径管件是由聚乙烯、球墨铸铁和钢制成的。由于腐蚀和接头失效的问题，在聚乙烯管道上使用钢或球墨铸铁配件是没有好处的。就大直径聚乙烯管件而言，这些管件有两种形式，制造和机械加工，尽管机械加工的管件仅适用于直径达1000mm的管件。最常用的大直径聚乙烯管件是通过制造大直径管段来制造的。然而，这种制造方法降低了结构的完整性，管道的操作压力必须降低（降级），有时高达80%，降低了管道的效率。目前唯一的全压力额定大直径聚乙烯管件是由实心聚乙烯块加工而成的，但直径只能达到1000mm。由固体制造的大直径全压力额定聚乙烯管件的成本从630mm管件的12,000英镑起。由于使用传统注射成型制造630毫米以上直径的配件的成型机和模具成本高达500万英镑以上，而且机加工配件的成本很高，因此公司已经确定了成型技术和配件设计，这将使制造成本降低到现有机加工配件的50%，同时提供了一个提供外部结构加固的设计。

The company is looking to research and develop a novel convection moulding process andpipe pup jointing techniques to enable the development of a range of moulded polyethylenepipe fitting profiles (equal tee, elbow, reducers and end caps) between the size of 630mm and2500mm diameter. The current state of art large diameter fittings are produced frompolyethylene, ductile iron and steel. There is no beneficial reason for using steel or ductileiron fittings on polyethylene pipelines due to issues with corrosion and joint failure. In termsof large diameter polyethylene pipe fittings, these are available in two forms,fabricated andmachine from solid although the machined fittings are only available upto 1000mm diameter.The most commonly available large diameter polyethylene pipe fittings are manufactured byfabricating large diameter pipe sections. However, with this method of manufacture thestructural integrity is reduced, the operating pressure of the pipe has to be reduced (de-rated)sometimes by up 80% reducing the efficiency of the pipeline. The only current art fullpressure rated large diameter polyethylene pipe fittings are produced by machining the fittingfrom a solid piece of polyethylene block, but only upto 1000mm diameter. Large diameter fullpressure rated polyethylene pipe fittings manufactured from solid cost anything from £12,000for a 630mm fitting. As manufacture using conventional injection moulding is cost prohibitive£5m + for the moulding machine and tooling to mould 630mm + diameter fittings and withhigh cost of machined fittings the company has identified moulding techniques and fittingdesigns which will reduce the cost of manufacture to 50% of existing machined fittings whilstproviding a design which provides external structural re-enforcement.