Infra-red heaters stick to their task

Edited by the Engineeringtalk editorial team Jan 19, 2006

The installation of an infra-red drying system from Heraeus Noblelight has allowed a specialist direct mail printer to provide in-house glueing of printed products.

The installation of an infra-red drying system from Heraeus Noblelight has allowed specialist direct mail printer, Abbey Direct, of Northfleet to provide in-house glueing of printed products, affording them the capability to greatly expand its customer base, while offering better control over the total production process.

Abbey Direct specialises in the printing of direct mail shots for a wide variety of customers.

Essentially, there are three stages of this specialist printing process.

First the main body of the item is printed on a six-colour offset litho machine.

Then the remoisten glue, which is necessary to seal the returnable section of the mail shot, is applied.

Finally, the specific details of the mail shot, such as address details, personalisation etc, are printed on a laser printing machine.

Abbey Direct has always carried out the offset part of the print production in-house.

Until recently, the glue application was subcontracted, mainly because of space restrictions, as a glue-drying station is required as well as a glue applicator because it is vital that the glue is completely dried before passing to the laser printing process.

However, in order to offer a better overall service to existing and potential customers, Abbey decided to investigate the possibilities of in-house glueing.

The problem eventually came down to devising a drying system which could achieve the required degree of glue drying in the space available.

This immediately ruled out a convection oven and radio frequency drying was also eliminated because of the inordinate cost.

After being advised that infra-red drying would probably provide the optimum solution, Abbey asked Heraeus to carry out on-site investigations using a portable, carbon medium wave unit.

These investigations proved so successful that a full-scale infra-red drying system was installed at the Northfleet plant.

This consists of two infra-red modules, arranged in two individually controlled zones and each containing nine 4kW carbon medium wave emitters.

In operation, the printed matter leaves the offset litho machine and is glued at a glue application station.

It then passes under the first IR module, whose emitters can be switched on and off in banks of three according to the width of the web to be dried.

The web's direction of travel is then turned through 180 degrees by the roller conveyor system so that it passes above the second module, which is thyristor controlled using a manual potentiometer to adjust the drying to suit production requirements.

This arrangement of the two zones has allowed the infra-red system to be installed within a length of just over a metre.

Currently the system is using only the zone 1 module to dry print at a rate of 122m/min, with the capability to increase this rate to 244m/min when the zone 2 module is switched on.

Since installation, the system has performed exactly as predicted, as Abbey Direct Director, Mark Cantwell, explains: "The infra-red modules were retrofitted very easily into the production line, within the restricted space".

"Operationally, because medium wave infra-red is ideal for this type of application, there has been no burning or scorching and the fast response of the carbon emitters also means that there is no damage to the paper in the event of unexpected line stoppage".

"Moreover, we can now offer a more comprehensive product and this is reflected by the increase in sales we are experiencing".