Category: Manufacturing technology

Thermoforming Materials | Vacuum Forming Materials | Pressure Forming Materials

Thermoforming Materials:

Thermoforming is a manufacturing process where a plastic sheet is heated to a pliable forming temperature, formed to a specific shape in a mold, and trimmed to create a usable product. There is a wide range of thermoforming materials that provide just the right properties for your plastic formed product, and each material has physical characteristics that make it suitable for specific applications.

Thermoforming-Vacuum-forming-materials-Pressure-forming-materials
Thermoforming-Vacuum-forming-materials-Pressure-forming-materials

Thermoforming Material & Description

ABS

Good general purpose material, very tough yet very hard and rigid, good impact and electrical. Available in gauges from .040 to .475 with several extruded textures. Comes opaque and can be matched in custom colors.

ABS/PC

A blend or alloy of ABS and polycarbonate that thermoforms well, weathers well, good color retention, very hard, excellent impact.

ABS/PVC

Flame retardant, tough.

ABS Plastic, ABS-PC, ABS-PVC products
ABS Plastic, ABS-PC, ABS-PVC products

Acrylic

Outstanding weather resistance, excellent optics and electrical properties, poor impact, high gloss and deep luster. Available in standard gauges from .080 to over 1″. Available in clear, transparent and opaque colors.

Acrylic, cell cast

Excellent optics and hot strength, more expensive. Acrylic, continuous and extrusion cast.
Large volume use and best price, good optics.

 

Acrylic film

3 or 6 mil film for laminating, decorating, and weathering of extruded ABS.

DR Acrylic

Modified acrylic with higher impact properties.

Acrylic/PVC

A blend of acrylic and PVC that is a tough, chemical-resistant material that weathers well and is flame resistant. Available in custom colors.

pressure-forming-products-intricate-contours-tight-radii
pressure-forming-products-intricate-contours-tight-radii

HDPE (high-density polyethylene)

Crystalline, very tough materials, good weather resistance with UV inhibitors, resistant to many chemicals. Available in standard gauges from .040 to .500. Available in opaque custom colors. Tough and stiff. Good low temperature. Economical.

HMWPE (high molecular weight)

Excellent environmental stress crack properties, thermoforms well, good low temperature.

HIPS (high impact polystyrene)

Good general-purpose material, rigid. Available in clear but usually opaque custom colors from .030 to .350, low cost.

pressure forming-housing-equipment's-electronics-parts-instruments
pressure forming-housing-equipment’s-electronics-parts-instruments

 

PVC (vinyl)

Good general-purpose material, good abrasion and chemical resistance. Available in clear but usually opaque custom colors from .030 to .125.

Expanded PVC

Stiff, light, flat, thermoformable. Available in stock colors and gauges, generally 3 and 6 mm but others also available.

pressure forming-sheet-gauges-covers-food-trays
pressure forming-sheet-gauges-covers-food-trays

PETG

Clear, higher impact than acrylic, easy to form. Available in gauges from .030 to .500.

Pressure_Formed_Parts-PETG (Polyethylene Terephthalate glycol), PET, PETE, PETP, PET-P
Pressure_Formed_Parts-PETG (Polyethylene Terephthalate glycol), PET, PETE, PETP, PET-P

Pressure Forming | Pressure Thermoforming | Blow Forming

Pressure Forming process:

The pressure Forming is the process used to produce injection mold quality, high definition plastic component parts, housings and containers without the huge expense of tooling. It involves positive pressure to force the heated plastic into the mold cavity. This is called pressure thermoforming or blow forming.

Pressure forming process, Positive molds, Advantages of pressure forming over thermoforming
Pressure forming process, Positive molds, Advantages of pressure forming over thermoforming

Pressure Forming Working Operation:

Pressure forming 20 to 150 psi pressure temperature controlled mold cavity
Pressure forming 20 to 150 psi pressure temperature controlled mold cavity

The highly versatile pressure forming process utilizes air pressure, from 20 to 150 psi, to force the heated sheet into a temperature controlled mold cavity. Vent holes are provided in the mold to exhaust the trapped air. The final part features sharp definition of intricate contours and tight radii. Textures and accurate details are built right into the tooling. Low-cost, highly aesthetic plastic parts of varying sizes are possible due to the application of air pressure, as well as more sophisticated process controls that better monitor tool and sheet temperatures while controlling material shrinkage during forming.

Pressure forming products, Intricate contours tight radii
Pressure forming products, Intricate contours tight radii

Types Of Molding operation:

  • Positive Mold
  • Negative Mold

Negative molds  have concave cavities. A positive mold has a convex shape.

Pressure forming, Blow forming, Thermoform Console automobile parts
Pressure forming, Blow forming, Thermoform Console automobile parts

Pressure Forming over Thermoforming:

The basic advantage of Pressure Forming over Thermoforming is the cost advantage for small production items. The mould cost for thermo forming is considerably higher in comparison to pressure forming thus for a lower quantity, precision job the best suitable method used is pressure forming.

Application:

Pressure forming is used to create in a wide array of plastic products used for packaging of food trays, blisters, covers, internal parts, housing equipment, bezels, bases, and spare parts for use in business machines, electronics, computers and peripherals, bio-medical applications, and instruments.

Features:

pressure-forming-housing-equipment's-electronics-parts-instruments
pressure forming-housing-equipment’s-electronics-parts-instruments

Pressure forming achieves features beyond the capabilities of vacuum forming including louvers, ribs, recessed areas, crisp details and logos.

Pressure forming is ideal for small to medium sized production runs that do not justify the high cost of injection molding dies. Additionally, because the aluminum tooling used in pressure forming has an unlimited life cycle, due to the non-abrasive process versus injection, it saves a great deal of money over many years of continued use. Pressure form tooling usually costs less than 10% the cost of an injection tool. There are also a significant time savings (sometimes 25%) in tooling lead time. Sheet gauges 0.020″ – 0.500″ are capable of being pressure formed.

pressure forming-sheet-gauges-covers-food-trays
pressure forming-sheet-gauges-covers-food-trays