Manufacture of extruded plastic hosepipe with lengthwise inner ribs has pipe ends made without ribs to allow for fitting accessories

摘要

The extruded hosepipe (1) with inner lengthwise ribs (3) is made e.g. in lengths of 25 and 50 m. Each pipe length has a zone (5) at each end that has no ribs to allow accessories such as connectors (2) to be fitted. The the extrusion operation can include a stage in which the production of the ribs is halted briefly, or the extruded ribs can be removed subsequently by a rotary bladed tool to leave a smooth inner surface.