Moulding Process
We have been providing quality products manufactured through Blow moulding, Injection moulding and Stretch blow moulding process for over 3 decades now. Our facilities and our people are what make the difference. From the initial part of drawing through tooling and production, we utilize our talents to create cost-effective solutions for you. We are totally customer focused and we offer all our clients with innovative packaging solutions to meet their expectations.
Extrusion Blow Moulding
Sometimes referred to as extrusion blow moulding (EBM) this process begins with plastic being melted and extruded into a hollow tube (parison).
The parison is then captured by closing it in a water cooled mould. Air is then blown into the parison inflating it so that the plastic takes on the shape of the mould.
Typical materials used: Polypropylene (PP), Polyethylene (PE),.
This versatile process allows the production of unique shapes, sizes and neck types in a variety of materials.
Injection moulding Process
The plastic injection moulding process produces large numbers of parts of high quality with great accuracy, very quickly.
Plastic material in the form of granules is melted until soft enough to be injected under pressure to fill a mould. The result is that the shape is exactly copied. Once the plastic moulding has cooled sufficiently to harden the mould opens releasing the part. The whole injection moulding process then repeats.
Typical materials used : Polypropylene (PP), LLDPE, LDPE, HDPE.
PET Moulding Process
Stretch blow molding is best known for producing PET bottles commonly used for water, juice and a variety of other products. Stretch blow molding has been used since the early 1970’s and has grown in existence with the primary use for making carbonated beverage bottles.
One of the major advantages of stretch blow molding is the ability to stretch the preform in both the hoop direction and the axial direction. This biaxial stretching of material increases the tensile strength, barrier properties, drop impact, clarity, and top load in the container. With these increases it is usually possible to reduce the overall weight in a container by 10 to 15 percent less then when producing a container in another way.
Stretch blow molding is divided into two different categories single-stage and two-stage.
- Single-stage uses the extruder to inject a parison into a preform mold where the plastic is rapidly cooled to form the preform. The preform is then reheated and placed in the bottle mold. The then softened parison stretches to about twice its original length. Compressed air is then blown into the stretched parison to expand to the bottles mold. Once the bottle is cooled the mold is opened and the finished bottle is emptied from the mold cavity. This technique is most effective in specialty applications, such as wide mouthed jars, where very high production rates are not a requirement.
- Two-stage stretch blow molding is the same as single-stage, except the preforms are already made. The single-stage process is usually done using one machine, where the two-stage process uses preforms that have already been made and cooled. This allows companies to either make or buy their own preforms. Because of the relatively high cost of molding and RHB equipment, this is the best technique for producing high volume items such as carbonated beverage bottles. In this process, the machinery injection molds a preform, which is then transferred within the machine to another station where it is blown and then ejected from the machine. This type of machinery is generally called injection stretch blow molding (ISBM) and usually requires large runs to justify the very large expense for the injection molds to create the preform and then the blow molds to finish the blowing of the container. This process is used for extremely high volume runs of items such as wide mouth peanut butter jars, narrow mouth water bottles, liquor bottles etc.