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柱连接技术，以开发一系列直径在630 mm到2500 mm之间的模压聚乙烯管件型材(等长三通、弯头、异径管和端盖)。目前最先进的大直径接头是由聚乙烯、球墨铸铁和钢生产的。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管接头没有任何有利的理由。就大口径聚乙烯管件而言，有两种形式可供选择，一种是实心制造的，另一种是机械制成的，尽管机械加工的管件直径只有1000 mm以下。最常见的大口径聚乙烯管件是通过制造大口径管段来制造的。然而，这种制造方法降低了管道的结构完整性，管道的工作压力有时不得不降低(降级)80%，从而降低了管道的效率。目前技术上唯一的全压力额定大直径聚乙烯管件是由直径不超过1000 mm的实心聚乙烯块加工而成的。由固体制造的大口径全压力额定聚乙烯管件的成本从GB 12,000到630 mm管件。由于使用常规注塑制造成本高达GB 5M+，造型机和模具要模制直径630 mm以上的管件，而且机械加工管件的成本很高，公司已经确定了成型技术和管件设计，这将把制造成本降低到现有机械加工管件的50%，同时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.