Infra-red system saves time, space and costs

Edited by the Engineeringtalk editorial team Mar 24, 2005

A carbon infra-red system has significantly reduced production cycle times and virtually eliminated maintenance costs and machine down-time for Faurecia.

By installing a carbon infra-red system to preheat acoustic soundproofing sheets prior to moulding, Faurecia has significantly reduced production cycle times and virtually eliminated maintenance costs and machine down-time on one of its major moulding machines.

Faurecia is a world leader in the supply of automotive equipment and its Washington, Tyne and Wear, plant produces acoustic products for vehicle interiors and luggage compartments.

Essentially, many of these products are produced by moulding a thick sheet of PE-EVA (polyethylene ethylene vinyl acetate) to the required shape and then applying a layer of polyurethane foam to impart the sound-deadening properties.

An essential part of the moulding process is the preheating of the PE-EVA sheet.

Some of the moulding machines at Faurecia apply this preheat before the sheet is dropped into the mould for forming and one such machine has recently upgraded its preheat system to incorporate Heraeus medium wave emitters.

However, one of the moulding machines at the Washington factory, relies on heating the PE-EVA blank while it is actually in the mould.

This heat was previously delivered by medium wave infra-red foil heaters, which were proving expensive to maintain.

Moreover, the slowness of the heating operation, which also involved preheating the blanks with large hot water radiators, was starting to create a production bottleneck.

In an effort to rectify this situation, Faurecia contacted infra-red specialist Heraeus Noblelight, which investigated the possibilities of retrofitting a more modern, more efficient infra-red system to meet the current requirements of the moulding machine.

Initial on-site trials immediately established that carbon infra-red emitters could eliminate the need for preheating, as they provided a 16% increase in heat-up rates.

Consequently, it was possible to dispense with the hot water radiators and associated stands and create valuable new floor space.

It also proved possible to retrofit the new carbon infra-red system using many of the existing electrical supply connections of the old system, as well as the existing control panel and pyrometer.

In operation, the blank sheets are now heated in the mould, without any pre-heat, by means of a 104kW carbon medium wave cassette, which carries 26 x 4kW twin tube emitters, arranged in 13 zones.

The emitters are switched on when the sheet is dropped into the mould and switched off by the pyrometer, on achieving a preset temperature.

Switch on/switch off times are less than 1s.

Since installation, it has been found that cycle times have been reduced by 20s and there are energy savings of 9kW/h because of the elimination of the preheating alone.

Furthermore, maintenance costs and duties have been cut dramatically, as the twin tube emitters are proving much more durable than the original foil heaters and any infrequent changeover involves minimum downtime.