square. The highest rates are among the suppliers 'Watlow' and 'BelTerm'. Electric heaters with insulators of periclase powder and similar materials cylindrical and rectangular shape (heating elements, cartridge) released a long time, are well known, gostirovany back in Soviet times and in this class of equipment are rarely used. To date elektronpagrevatelyam with such insulators include duct heaters (spiral heater) for hot runner molds. They are made of rectangular tubes of small cross section and can curl into a cylindrical spiral. Method transfer of heat flux to the heated object – the thermal conductivity and radiation, operating temperatures on the surface of the electric heater of more than 700 degrees. C. Since the transfer of heat flux to the heated product in these electric heaters going through an air gap, their efficiency is low and energy costs and the cost are large.
Somewhat improve the energy characteristics of electric heaters can use of external reflector tube and the inner shell to be installed in a heated facility for dense planting. In this case, the cost of electric heating is becoming more and complexity of installation on heated object increases. Alternatively, the above-mentioned electric heaters, in most cases, objects with diameters of 25 mm and more, much cheaper and easier to use a ring heater family 'ThermoRang 8,5' (supplier 'BelTerm'), transmitting the heat flow object thermal conductivity and having higher rates of reliability and power consumption. Variety of designs of heated objects and defines variety of designs of electric heaters. Today, the market for modern electric heaters are ring (they Clamp, banding, Obruchev), including disclosures to be installed in a heated object and replacing most of the semiring and arched, but with a simplified installation and connection, flat, spiral, etc.
with all kinds of insulators listed above. In this case, the best value 'price – quality 'are high quality electric heaters with insulators of mica material suppliers such as' WATLOW' and 'BelTerm'. With technology of manufacturing of electric heaters with a density heat flux up to 8.5 W / cm. square. they can create highly compact design of annular, flat, etc. of electric heaters, simply embedded in the modern technological equipment, and in most cases replace the outdated energy-intensive electric heaters.