Material and DRY Molding Process

Dry molded expandable foams such as “expanded polystyrene” (EPS) and “expanded copolymers” (such as “Dytherm” polyphenylene ether-polystyrene and “GECET” polyphenylene oxide-polystyrene) are produced by a unique, patented, heat-conducted process. The process uses machinery and molds made in our shop that are specifically designed for reliable, long-term production of high quality, molded parts.

The process features accurate mold alignment for single or multiple cavity molds, calibrated raw material filling (your molded part density is quoted in a range of densities from 2.0 lb/ft³ up to 37lb/ft³), and precise temperature control during automatic and semi-automatic machine molding cycle.

Your finished molded parts will have: (1) clean, dry, smooth surfaces on which your surface details stand out sharply; (2) solid material fusion for glossy smooth appearance; this results from steam jackets in the mold wall which provides even heating of the mold wall,  (3) precise dimensions.

Tempo produces a variety of expanded densities each day for unique customer applications.  The material is expanded in one of four pre-expanders which work like sophisticated popcorn poppers to expand the resin to the desired weight. (You can see some of the lighter weights on the Density Conversion Chart on this website).

Molds and Warranty -

Tempo’s unique DRY molding process uses “open architecture” mold design.  This means that the mold is built around the customer’s part design and that the molded part designer is not constrained by conventional WET mold steamchests in which mold inserts are mounted.

Molds can be designed to produce simple and also complex parts, with multiple retraction sections.  Each mold section is heated and cooled under separate control.  Tempo can produce no-draft and undercut parts, using design techniques such as collapsible cores and “tulip” mold design in which mold surfaces retract like a tulip flower allowing molded detail in areas under what would conventionally be the parting line. 

Your molds are capable of withstanding the repetitive clamping pressures and heat reversals of many years, and Tempo warrants these molds to produce as outlined in the Warranty below.

-          Tempo warrants that your mold investment goes directly into high quality, permanent molds. You have direct communication with us during mold development, an essential element for first molded articles that meet your expectations. Our mold warranty reads on every quotation as follows:

"We agree to bear the expense of all mold repair and maintenance throughout the Mold Warranty period stated as: “ 800,000 quality parts.”  At expiration of the Warranty Period, any required mold repair or maintenance will be charged at cost, with prior Customer approval, which shall not include repairs to ancillary items such as Fillers, Plumbing and other Mechanical Devices not integral to the mold."

Production Machinery
Starting in 1960 with high volume production of smooth-surfaced, thin-walled coffee cups, Tempo developed and patented its own production machinery. Customers with thin-walled or intricate, difficult to mold requirements now benefit from Tempo's experience.

Designed for reliable productivity and easy maintenance, Tempo's twenty five molding presses and four pre-expanders handle a wide variety of simultaneous molding jobs. Whether you need a high or low-volume production run, we have the capacity to meet your schedule.

Molding presses are mounted on a raised platform which delivers utilities from below to each molding machine. Each machine has separate heating and cooling valves which control how the installed mold is baked and cooled.

 

Co-Generation System Means Pollution Control

The hydrocarbon blowing agent pentane is used for expandable foams because it allows the raw material to have good shelf-life. Pentane is a VOC (volatile organic compound).  It is a naturally occurring molecule but is a "precursor to ozone" which must be controlled for air pollution reasons.

Tempo developed a unique method of capturing pentane from the molding process. The overall goal was to reduce utility expenses while achieving air quality compliance. The EPS molding process uses utilities including steam, electricity and compressed air.

For clean manufacturing, Tempo captures the air within the building and pulls it into a turbine cogeneration system which generates electricity, steam and compressed air.  Third party testing proved that Tempo meets air quality standards. This concept has wide application in other industries which have VOC emissions and need electricity and heat, such as bakeries.
 

Tempo's machine technology developed from early
cup production to custom thin-wall molding