Calesco Foil of Kolbäck, Sweden, designs and manufactures flexible electric heating elements that can be adapted in various ways to counter the effects of cold weather work. Applications Director Kjell Eriksson believes that workers on exposed offshore platforms could derive numerous benefits from being able to work with heated equipment.
"There is nothing new about electric heating elements as we have been making them for a wide range of applications for many years," he says. "However, in that time we have built up a level of experience and technical know-how that enables us to design and manufacture elements to suit virtually any application. It is now possible for a customer to specify a temperature he wishes the item to be heated to, tell us what voltage he has available and we can make an element that will reach and maintain that temperature without recourse to thermostats or other control devices."
A foil heating element may comprise one or more layers of insulation and one or more metallic conductors. Among the insulating materials used are PVC, polyester, polyamide, silicone rubber, and micanite. The conductor material may be a resistance heating alloy, copper, brass, or aluminum with thickness of 10 - 100 uM. A foil element facilitates even heat distribution over a wide surface using operating voltages from one or two volts up to 500 V. Element temperatures can range up to 400° C and because the foil is sealed, it can be immersed in water and used for critical components such as valves that must remain frost-free.
Design freedom
Calesco Foil's customized elements may comprise both a heating-up and a temperature holding circuit. Because the elements are flexible, they can be mounted to completely envelop a body/container, thereby insuring maximum heat transfer. The element can also be designed to provide different levels of heating across its surface. This facility is particularly useful in situations where uneven heating could occur through temperature loss at the element's edges.
Boots and gloves heated by small batteries could make life much easier for oil industry workers operating in extreme climates, Ericsson says. In addition to metal foil elements, Calesco also offers elements that use polymeric conductive plastics, which have applications such as keeping moisture out of electric control boxes.
For more information, contact Kjell Eriksson, Calesco Foil. Tel: +46 220 453 30, fax: +46 220 453 50, email: [email protected].
Thermal imaging reveals how a flexible element can be used to keep a valve at optimum working temperature.
