Technology
heating method
Objects are dried by heating, or undergo various processing after heating, all of which are inseparable from the heater. Choosing the correct heater can avoid heat loss, achieve the best effect, save energy and reduce costs.
Heating methods can generally be divided into three types: conduction, convection and radiation. Electric pans, electric kettles, and electric irons belong to conduction heat. After the electric heating tube heats up, the heat is transferred from the electric heating tube to the mold by conduction, and the temperature of the mold rises accordingly. . This way of heat transfer from objects with high temperature through contact is called conduction.
In a common oven or high-temperature furnace, after the heating wire or the electric heating tube heats up, the air in the furnace is convected, and finally the temperature in the furnace is raised. This effect of dissipating heat and increasing temperature through air flow is called convection.
Radiant heat is a heating method of infrared rays. The method of heating objects through infrared radiation is called radiation heating.
Infrared is an electromagnetic wave (microwaves, X-rays, and light waves all belong to electromagnetic waves), which travels in a straight line and does not require the transmission of a medium.
Generally, conduction heating must transfer heat energy through the medium, and convective heating also requires air medium to transfer heat energy.
For heating generally used in confined spaces, it is recommended to use convection heating, because in confined spaces, as long as the insulation is done well, the heat will not be easily lost and the temperature can be raised quickly.
In the open space, as long as there are some gaps, or the insulation layer cannot be done well, it is recommended to use infrared lamps to avoid heat loss and loss. (e.g. conveyor belt operation)
The traditional heating method of black body tube, quartz tube, and electric heating tube is to heat up the outer metal tube, black body tube, and quartz tube after the electric heating wire is energized, and then transfer the heat to the object to be heated by conduction into convection.
This method consumes energy, heats up slowly, and cools down slowly. 1-2 seconds after the infrared lamp is started, it can radiate heat to the object to be heated, and it does not store heat at all, so the temperature rises and falls very quickly.