In the extrusion blow molding process a tube of polyolefin plastic is extruded through a pin and die. This plastic tube is then cut and pushed into a chilled blow mold with low pressure air to form the bottle shape.
In order to capably complete this bottle blowing process, Graham uses extrusion blow molding machines consisting of both wheel and shuttle equipment.
- EBM Wheels: In general, wheels are used for higher volume manufacturing where fast cycle times and higher cavitations are beneficial. The higher output of wheel equipment is ideal for on-site application where the speed of the EBM wheel is a good match for that of the filling line. In addition, wheels are used for multilayer application where the equipment's layer structure capability is better than that of shuttles.
- Shuttle machines tend to be used for shorter run lengths where higher flexibility may be needed or for bottles with more specific neck designs.
Unlike most plastic bottle manufacturers, Graham has the advantage of having both wheels and shuttles in its EBM machine portfolio. This ensures that the best technology is always available to meet customer requirements.