Heating pads are designed and made to order

Edited by the Engineeringtalk editorial team Sep 26, 2006

To meet the needs of the most demanding heating applications a comprehensive custom heating pad design and manufacturing service is offered by Acal Radiatron.

To meet the needs of the most demanding heating applications a comprehensive custom heating pad design and manufacturing service is offered by electromechanical thermal management specialist Acal Radiatron.

The capability has recently been further expanded with the introduction of high power density printed-element heater pads operating at temperatures up to 650C and smart self-regulating heater mats for lower temperatures.

From a flexible portfolio of material and manufacturing technology options the company can fabricate heating pads to custom specifications ensuring best-in-class thermal performance as cost-effectively as possible.

A joint-development approach to achieve optimum design solutions often brings value-added benefits due to the company's wide-ranging capability coupled with extensive and proven expertise.

This philosophy repeatedly delivers the right product with the right price at the right time, says the company.

New applications are emerging every day.

Typically, the pads, mats and heating elements are used for surface heating in food processing, catering/medical equipment and similarly diverse applications.

In outdoor cold-weather applications the pads are used in areas such as condensation protection in system enclosures of all kinds, from telecomms basestations to point-of-sale and remote systems requiring stable operating temperatures.

As equipment generally becomes smaller and more compact, and as power consumption issues concern designers, the pads are proving increasingly popular as wafer-thin space-saving alternative to cumbersome air-conditioning units, for example.

The pads can be produced in virtually any shape or form and may be flexible or rigid depending on end-user needs.

With extremely low thermal mass they can be designed to offer fast-acting or steady heatflow evenly distributed right across the pad surface avoiding excessive thermal gradients, cold spots or can be zoned into selective areas.

To achieve this, the company can exploit a range of separate element technologies and dielectric materials.

These include fixed resistance etched foils, resistive wire or variable resistance conductive inks and alloys depending on power density, size and volume requirements.

Printed directly onto steel or ceramic gives the lowest mass and high temperature performance.

Other dielectrics include silicone rubber (to 260C), polyimide (Kapton) (to 200C), polyester (to 120C).

They are typically supplied with connection wiring to suit individual needs and are subsequently temperature controlled by switching circuitry such as bi-metal thermostats or solid-state NTCs.

In addition, the company now offers self-regulating heat pads which change their resistance in proportion to the surrounding ambient temperature - so the colder it becomes the harder the heater works.

They are manufactured using a specialised PTC polymer printed ink element which features interleaved bus bar technology to produce multiple parallel circuits across its surface.

Ideal for lower temperature start up, anti-condensation or defrost requirements - examples include self-governing automotive, scientific and industrial heating requirements.

The pads respond quickly to ambient temperature variations to cost-effectively maintain an optimised and regular operating temperature, typically from -60 to +70C.

For speed and flexibility, the company offers a preferred range of standard stocked silicone heater mats.

It can also supply custom produced, fast turn (2 days possible) silicone pads for low-cost initial design, development and prototyping requirements which may later be finally fabricated from one or more of the optional technologies.