China U Molding Plastic Trim PricelistRubber Sealing T Strip（TPR&PP&PVC&TPE) China FactoriesShower Door Plastic Trim ManufacturerWholesale Front Door Rubber Seal FactoriesWholesale Polyurethane Wear Strip ManufacturerWholesale Rubber Seal Shower Door for Sale
Moulding threaded plastic mouldings is a specialised part of the plastic injection moulding process. The main challenge of threaded mouldings is removing the moulding from the moulding tool.
To find out about other methods of making threaded mouldings as well as other specialist moulding processes, visit the Toolcraft advice pages at http://www.toolcraft.co.uk/advice-plastic-injection-moulding.htm?utm_campaign=threadedmouldings&utm_medium=video&utm_source=youtube
Mouldings with thread on the outside
Mouldings with thread on the outside can generally be made by making a mould tool with half of the thread in the core and half of the thread in the cavity. That way, the moulding can be removed from the tool without problem.
Mouldings with thread on the inside
However, to obtain a plastic moulding with the thread on the inside, or a moulding with the thread on the outside where no join lines may be visible, a different process is needed. For these mouldings, a removable threaded core is placed inside the mould tool. The polymer is injected into the mould tool and sets around the core to create the thread. The core and the moulded part are then removed from the mould tool and the core must then be removed from the moulded part.
This video shows how this is done in an operator-based process. The operator places the core in the mould tool inside the injection moulding machine.
The moulding machine now injects polymer into the mould tool.
The polymer sets inside the mould and around the threaded core to create the thread.
The core and the moulded part are now removed from the mould tool. Normally, there will be two cores so that one can be placed back immediately for the moulding machine to continue moulding.
The core is now removed from the moulding with a power drill.
Finally, the sprue is cut off and the moulding is finished.