Apex Plastics are professionals in (EBM) extrusion blow molded plastic products.

There are several types of blow molding processes, extrusion blow molding being the most common. Extrusion blow molding utilizes the combination of electrical and mechanical energy to heat plastic pellets that are fed into the extruder and turn them from solid to semi liquid state. The molten plastic is then pushed by the screw through an extrusion head on the blow molding machine. This extruded plastic called the parison, is a hollow tube that will be come the blow molded part. The parison is closed inside a mold and air is then blown into it forcing the plastic to the shape of the mold. The extruded plastic is initially cooled inside the mold by chilled water and is then removed from the mold and allowed to finish cooling at room temperatures.

Extrusion blow molding can be performed two ways, either continuous or intermittently. Apex utilizes the continuous method where the parison is extruded nonstop. Intermittent EBM involves interval-based extrusion of the parison and is commonly used for large thick-walled parts.

Producing extrusion blow molded plastics products is a less expensive process than injection blow molding and can provide a wide variety of barriers and features such as handles, but the dimensional accuracy is not as well controlled. Some materials such as PET and standard PP homopolymer are difficult to impossible to extrusion blow mold on a commercial basis due to their low melt viscosities. However, polypropylene and polyester copolymers are available which can be extrusion blow molded acceptably. The parison (hot hollow plastic tube) is extruded through an annular die. The thickness of the parison is controlled in the die by varying the wall thickness of the parison, whilst leaving the outside diameter the same. This is accomplished by having a conical inner sleeve, which can be moved up and down in the die, resulting in a controlled variation in wall thickness of the parison.