Muffle furnace heating element

The heating element is an important member of the resistance furnace is a resistance furnace heat sources. Understand the performance, structure and characteristics of the heating element material, it is very important for the correct use of the resistance furnace.
Surface load of the heating element and the shape
Surface load of the heating element
When the current through the heating element, due to the role of the resistance of the heating element, the electrical energy into heat energy conversion law in line with Joule's law. Heating element electrical energy into thermal energy by heat conduction, convection and radiation distributed to the furnace, the ability to disseminate the surface load. The surface load of the heating element is defined as the power per unit area on the surface of the component can be distributed W/cm2. The larger the surface load of the heating element, the more heat comes out of the heating element itself, the higher the temperature. Consider increasing the element surface of the load may be correspondingly reduced surface area of ??the heating element, reducing the amount of heating elements, but is not conducive to the lifetime of the elements from the heating power of the resistance furnace. Conversely, reduced element of the surface load can be a corresponding increase in the surface area of ??the element, and is conducive to the lifetime of the elements, but increased the amount of the heating elements. In addition to the cooling effect of the surface load on the heating element, its shape also have a certain impact, in general, the ribbon components than the linear thermal conditions, the surface load.
Common shape of the heating element
The shape of the heating element depending on its material and installation, linear, spiral, mesh, ribbon and the rod-shaped structure, wherein the metal heating element is generally linear, spiral, a mesh or a ribbon, as opposed to metal heating element is generally rod. Linear heating elements in the oven cavity made of metal wire around certain requirements from the system; spiral heating element is wound into a spiral wire first and then install the oven cavity; mesh heating element wire braid and into; ribbon heating elements are made of metal directly processed into.