Large Thick vacuum forming Plastic Medical Appliance Cover Machine Shell
8 key components of the vacuum forming process : clamping, heating, sheet level, pre-stretch, vacuum, plug assist,
cooling and release, and finishing and trimming.
A clamp frame is used to ensure the plastic sheet is held firmly in
place during the vacuum forming process. It is important that the
clamp frame is powerful enough to handle the thickest materials
expected to be used with the machine: this tends to be up to 6mm
when the machine has a single heater, and 10mm with twin heaters.
Now that the plastic sheet is securely positioned over the opening
of the vacuum forming machine it is time to heat it up: this is
typically done using radiant heaters.
The heaters are mounted within an aluminium reflector plate and use
infra-red elements; they move into position both above and below
the sheet when it is time to heat the plastic. There are also a
series of zones controlled by energy regulators to ensure that the
heat applied to the plastic sheet is uniform, both throughout the
depth and over the surface area.
There are a variety of heaters that can be used for different
requirements, including single heaters, twin heaters and quartz
The sheet level stage is one that ensures the sheet isn't sagging
down too much into the machine during the vacuum forming process. A
built-in photo-electric beam scans between the bottom heater and
the sheet of plastic; if the sheet of plastic sags down, therefore
breaking the beam, a small amount of air is injected into the
bottom chamber to lift the sheet up.
When the plastic has reached the correct forming temperature
through heating it then needs to be pre-stretched to achieve an
even wall thickness when the vacuum is applied. Air is introduced
to blow an air 'bubble' of a controlled height into the plastic
sheet. The mould is then raised into this pre-stretched sheet ready
for the next stage.
Now that the mould has been raised into the sheet a vacuum needs to
be applied to assist in forming. A dry vane vacuum pump uses air to
suck the sheet into the mould to eliminate any trapped air and
ensure the detail of the mould is properly picked up.
With much larger machines a high volume capacity vacuum pump is
used alongside a vacuum reservoir to enable faster moulding of the
heated sheet before it drops below the correct forming temperature.
Cooling and release
Now that the plastic has been formed it is critical to let it fully
cool before being ejected from the mould. If it hasn't cooled fully
the moulding could become deformed which would result in a reject
Often high speed fans are used to speed up cooling, or a fine mist
of chilled water which used with the fans can reduce cooling time
by up to 30%. Once the material has fully cooled it can then be
released from the mould by using a small amount of reverse air
Finishing and trimming
Once released the part is transferred to the trimming station for
removal of excess material, finishing and any other required
post-forming process. These could include drilling holes, slots and
cut-outs into the part and any required decoration, printing,
reinforcing and part assembly.
|Process Of Kind||ODM/OEM|
|Main Products||Thick vacuum forming product, Thermoforming product|
|Main Procedures||Designing, Moulding, Silk-screen,Vacuum Forming, 5-axis CNC
Cutting, Trimming,Scraping, Polishing, Spary painting, Sonic
|The max product size can be up to 3000*1800*1000mm(L*W*H).|
|Thickness||The material thickness can reach 10mm.|
|Colors||Any color as you required|
|Application Field||Packaging, Vehicles, Agricultural, Auto parts, Healthcare, Toy
Accessories, Decorative Field, Catering Household Appliance,
Tourism, Printing, Furniture Store and Supermarket Display, Medical
Facility and other Machinery Accessories and Components etc.|
|Packing||EPE, polyfoam, carton, or other required packing materials|
|MOQ||500, it's negotiable|
|Delivery Time||Within 25 working days after sample confirmed.|
|Payment Terms||T/T,L/C,Western Union,MoneyGram|
|Main Markets||North America, South America, Eastern Europe, Southeast Asia,
Africa, Eastern Asia, Western Europe...|
|Main Customers||BYD,Coco-cola.Pepsi,NSE,Glen Dimplex,Terraboost,ect..|
|Industry Standards||ISO 9001:2008 Certified, TS16949|
Vacuum forming is well suited to large parts with moderate volumes.
It offers lower cost tooling and quicker prototyping than other
alternatives. Contact us to find out how vacuum forming can be used for your application.