Blow molding screws are made different from any other screw for the plastics industry. The blow molding machine screw is designed to provide a high through put with a very good mix of a material that it is designed for. Unlike injection molding where a machine will run many different types of material a blow molding screws are normally designed for a specific type of material and application.
With a screw having to supply a head that has anything from a coat hanger type of head or a spiral head the screw is designed to give a melt and flow of material to allow flow though the head and a controlled parrison. When working with a multi layer head the melt stream needs to be consistent and with a very controlled mix. Whether you run gas tanks, bottles, drums or mail boxes you have to have a controlled flow and mix.
Most Blow molding screws are made of 4140 base metal with either a col 56 for a standard hard facing and chrome for easy cleaning to make color change over as quick as possible. Almost all screw are designed for a blow molding machine with a barrier design for a better flow of material and pounds per hour rate per rpm of the drive. The barrier will allow the material to move from feed to die head with less shear but a very good flow and consistency. I a lot of cases the screw will have a mixer if the machine is going to run color application, the barrier folds the material and the mixer will make sure the color is blended so part quality if as good as it can be.
OEM types of blow molding screws we supply include:
Please contact us directly with any of your questions or requests at (770) 427-3834.