That said there are many advantages including quality control throughout the production cycle, shorter production lead times, and cost efficiencies. Most comparisons relate to the injection molding process, the most common process used in the molding of plastic. These advantages include:
By offering thermoforming with in–house sheet extrusion EXT offers many advantages including quality control throughout the production cycle, shorter production lead times, and cost efficiencies.
Relatively low mold costs: Typically production tooling for thermoforming is only a small ratio of the cost for injection. The larger the tool the more favorable the cost of thermoformed tooling becomes. On larger parts tooling for thermoforming is often near 90% less expensive.
Relatively short lead time to production: Typical lead times for production thermoformed tooling are 10-12 weeks shorter than for injection mold tooling. In a marketplace where lead times have been squeezed this can often be the critical difference in molding process choice.
Flexibility of product wall thickness: The thermoforming process allows for different wall thicknesses to be created from the same tooling. This can be critical as new parts are brought to market, when part requirements change for a product, or when different versions of the same part , i.e. standard and heavy duty are desired.
Better physical Property of finished parts: Injection molded parts have invisible seams, or weld lines, where molten plastic met in the molds during production. These weld lines are structural weak points and will be the areas that the parts will crack under impact. Thermoformed parts are made from solid sheets of plastic; they have no weld lines and are more impact resistant. The flow of plastic material into the injection molds also leaves residual stresses which can lead to warping, particularly in larger, ideally flat products.
Very large part production: EXT thermoforms parts up to 118 inches by 76 inches wide. Few injection molding machines are capable of producing parts of this size , not to mention larger parts being manufactured that are up to 14 ft. x 20 ft. that are simply not possible in the injection molding process.
Pressure forming: High pressure thermforming of plastic sheet produces high appearance parts with many of the features and high tolerance that are typically thought of as injection molded features.
Ability to decorate/laminate/print pre-forming: In heavy gauge thermoforming there is a broad range of laminates available or pre-forming decoration that eliminates the requirement for secondary processes. Wood grains, marble, metallic appearance laminates are the most common of these laminates. Distortion printed sheet material is a more highly detailed, pre- printed and decorated sheet that with tight register creates impact 3 dimensional parts.