Tubular Heater
Perfect tubular heaters are used for practically the entire range of electric resistance heating applications.
A metal sheath material is selected. The proper size resistance wire for the heating element is carefully selected and verified by computer calculations to ensure the longest service life possible. The high quality resistor wire is carefully tested and inspected to meet rigid specifications prior to being coiled.
The resistance wire of the tubular heater is then welded to a terminal pin to assure positive connection. The wire is centered in a metal sheath and insulated with high quality magnesium oxide which is highly compacted around it and acts as an electrical insulator.
This material readily conducts the heat from the coiled resistor to the metal sheath and puts the heat where it is required, which results in maximum heater life.
Highly adaptable, the tubular element, in its many forms and as a component of Perfect packaged heaters and systems, has vastly increased the scale of electric heating applications.
The heaters’ mechanical and electrical flexibility are important to process engineers and product designers alike, as heating requirements can be matched accurately by proper selection from a great variety of element lengths, sheaths, diameters and watt densities.
Product Uniformity
Electric tubular heating elements provide a method of applying the exact amount of heat required at a specific area. When used with appropriate temperature control, product repeatability is assured.
Increased Production
Adding heat to a process often leads to increased production. For example, drying time may be reduced by heating the air or the product being dried. Chemical and cleaning processes are often more efficient when heated and a more consistent finished product results.
Less Down Time
OMEGALUX quality tubular heaters with properly applied watt density and sheath material will provide long life, less down time and little or no maintenance.
Typical tubular heaters instalations and uses
In Free Air
For applications like ovens and drying cabinets, tubular heating elements are compact, rugged heat sources. Their formability permits fitting around other oven components and work protrusions, concentrating heat at any point.
In Moving Air
Compression fittings, factory mounted fittings or brackets will mount a tubular element in a duct or air heating chamber.
In Liquids
Tubular heaters listed may be mounted through the side wall of a tank with compression fittings or by factory mounted fittings.
Transferring Heat to Metal Parts
The available diameters, lengths, ratings, watt densities, cross-sections, and maximum temperatures provide the solution for a given job.
Inmersion in liquid heating
Water and water solutions can generally be heated to any desired temperature. If liquid is under pressure, temperatures should not exceed the maximum sheath temperature of the element minus 100°F.
Oil heating
Steel sheath elements can be used for heating oils, heat transfer oils and other solutions not corrosive to steel sheath.
Air & gas heating
Use watt densities compatible with work temperatures. Refer to Technical section of this catalog. Heaters mounted horizontally must be supported to avoid sagging at high temperatures.
Proper spacing of supports may vary with application temperature, element diameter and sheath material. Generally 12 to 18″ spacing of supports is adequate.
Where air flowing over elements permits use of higher watt densities, make sure air flow is evenly distributed. Allow approximately 1/8″ per foot of element length for expansion and contraction of elements (i.e., 24″ long element could expand 1/4″ when energized).
Clamp-on heating
Use watt densities compatible with work temperatures. Refer to Application Guide for Tubular Heating of Solids, Liquids, Air & Gas or use curve G-175S in Technical section. Heaters should be clamped tightly for good heat transfer but should be allowed to expand as they heat up. Heaters clamped too tightly will bow away from the heated surface which results in poor heating efficiency and possible heater failure. It is generally best to tighten the middle clamp first to hold the element. Other clamps should be tightened enough to hold, but back off 1/2 turn to allow for expansion and contraction.
Heaters should be spaced on approximately two inch centers minimum.
Heaters are commonly installed by clamping into machined grooves for better heat transfer.
