What is EBM(Extrusion Blow Molding)?
In extrusion blow molding (EBM), plastic is melted and extruded into a hollow tube (a parison). This parison is then captured by closing it into a cooled metal mold. Air is then blown into the parison, inflating it into the shape of the hollow bottle,container or part. After the plastic has cooled sufficiently, the mold is opened and the part is ejected. Continuous and Intermittent are two variations of Extrusion Blow Molding. In Continuous Extrusion Blow Molding the parison is extruded continuously and the individual parts are cut off by a suitable knife. In Intermittent blow molding there are two processes: straight intermittent is similar to injection molding whereby the screw turns, then stops and pushes the melt out. With the accumulator method, an accumulator gathers melted plastic and when the previous mold has cooled and enough plastic has accumulated,a rod pushes the melted plastic and forms the parison.In this case the screw may turn continuously or intermittently.
EBM processes may be either continuous (constant extrusion of the parison) or intermittent. Types of EBM equipment may be categorized as follows:
Continuous extrusion equipment
rotary wheel blow molding systems
shuttle machinery
Intermittent extrusion machinery
reciprocating screw machinery
accumulator head machinery
Material used in The Extrusion Blow Molding Process
1. Polyethylene(PE)
LDPE- Low Density Polyethylene HDPE- High Density Polyethylene
2. Polypropylene(PP)
3. Polyethylene – Terephthalate(PET)
4. Polyvinyl chloride(PVC)
Products made of Extrusion Blow moulding
Using Extrusion Blow moulding following products can be made:
Using Extrusion Blow moulding following products can be made:
Bottles and containers,drums
Automotive fuel tanks
Hoses/pipes
Venting ducts
Watering cans
hollow industrial parts such as boat fenders etc
