HEATING ELEMENTS FOR OVEN
FIXED OVEN: TOP HEATER ELEMENT
Heater elements in the ovens are, as can also be seen once the oven doors are opened, located in the upper space and perform cooking functions through two ways: by convection or radiantly. First function is performed by the mentioned top heater elements with a moderate specific load which does not exceed 750°C. From this point of view and considering the shorter dimensions of the oven as well, we can say that the power is generally between 800 – 1100 Watt ranges. Therefore, the specific surface load corresponding to this power is 4 Watt / cm².
The second most typical way of radiating heat is through grill-type cooking elements which are generally known as the "grill resistances". The heater element in this type of cooking is around or higher than 800°C. Reaching that temperature, on the other hand, can be possible by the powers between 1500 and 2000 Watts. The specific surface load corresponding to this power range can be between 5 to 7 Watt / cm² range subject to the length of the element. Ovens are often manufactured in combinations where the top heater element and the grill element are used together. With regard to the most important grill resistance, we see that they are opposite to each other as to form with the top resistance + grill resistance combination.
It is known that each form and geometrical structure of the element gives out different thermal diffusion and cooking. Thermostat bars of appropriate form which are placed in a protective sheath are used to adjust and control the thermal hotness within the heated volume. General characteristic of this type of products is that they are fixed in the oven by means of one or more support bars.
Different types of heaters which are detachable and removable by retracting from top to facilitate cleaning of oven ceiling are also offered for use.
FIXED OVEN: BOTTOM HEATER ELEMENT
Lower heater elements are often mounted in the clearance under the inner space surface to ensure easy cleaning of oven cooking space. The protective sheath provided by the bottom of the oven and the electrical power designed with an average lower value function as a natural convection in ensuring the heat transfer.
Under equal conditions, the convective heat transfer efficiency is higher in this and similar product groups compared to top heater elements, because locating the heater on the bottom ensures it to perform easier natural convection by circular movements.
Heat flux direction and isothermal cooking environment depends on the shape of the heater which is designed according to the surrounding of the space to be heated. So that convective air flow is provided towards the center of the oven from its sides. Shapes provided herein are only some of the most renowned ones designed for this function. The required power is often between 1000 - 1300 Watt range. Specific surface load on the heated surface varies between 2 to 4 Watt / cm². Anticipated typical configuration is usage of only one heater element. Furthermore, double-element serial or parallel solutions can be used for very special applications (e.g. pyrolytic). Resting of thermal performance requests at reasonable levels and wide geometrical tolerances allow using more limited heater elements and also drop the cost of the heating function.
PROPELLER OVEN: ARTIFICIAL CONVECTION HEATERS
Propeller cooking function is generally characterized with high specific surface loads between 7 to 12 Watt / cm² range - this is a result of development of high power value and smaller dimension combination. The shape of the heater element is always circular which surrounds the fan that ensure air flow and it consists of one, two or three adjacent windings. According to the simple design specifications presented below, 6.1 and 6.40 mm pipe diameters are available in our production. Power level for double-winding heater is between 1500 and 2500 Watts and it can be up to 3500 Watt for triple winding heater. These elements are suitable for properly dimensioned, fixed applications generating heat through quenching, which provide air flow to all directions. This method also avoids resistance filament melting as a result of overheating.