The surface load of the finned heater is important!
Surface load refers to the load power per unit surface area of the electric heating element, and it is a key index that affects the life of the electric heating element. Fu Lan reminds users that the surface of the electric heating element meets strict control requirements, and it is not appropriate to be too large or too small.
If the surface conformity is too small, it consumes a lot of materials and is difficult to arrange. Furthermore, in some compact arrangements, the heating element, especially the spiral resistance wire, is very close to each other, it is difficult to dissipate heat between them, and it is easy to cause adjacent resistance. The temperature of the wire obviously exceeds its designed maximum temperature; in addition, it is easy to deform at high temperatures, and it is easy to cause adjacent resistance wires to be very close to each other in severe cases, and the furnace gas impurity carbon black, etc., more or less adheres to it during long-term work and causes resistance There is a local short circuit between the wire loops, and the resistance wire is fused here to force the shutdown of the furnace for maintenance. This is a common occurrence in the industry and an important reason for the short period of normal use of high temperature resistance furnaces.
If the surface is too large, the temperature difference between the heating element and the workpiece will increase, and the heating element will often be near or even exceed its designed maximum operating temperature for a short time. For large high-temperature resistance furnaces, it is recommended to use a wave-shaped resistance wire with the least shielding effect, and install it in a vertical hanging structure.
The air electric heating pipe has the characteristics of simple structure, high mechanical strength, high thermal efficiency, safety and reliability, convenient installation, and service life bench. Widely used in various saltpeter tanks, water tanks, acid and alkali tanks, air heating furnace drying boxes, hot molds and other devices.
As a professional manufacturer, Fulan wants to tell everyone that the quality of air electric heating tubes has a great relationship with the resistance wire.
As soon as an electric current passes through the finned heater, it generates heat, and the resistance value changes (increases) with the temperature rise. Therefore, when determining the resistance wire resistance of an air heating pipe, the resistance value at room temperature as a reference must be used by subtracting the changed part from the resistance value at the temperature. The resistance change rate of the air electric heating tube is caused by various factors, and it varies with the type of resistance wire and the use temperature. Therefore, it is very important to choose the resistance wire used in the air heating tube. The responsible manufacturers will choose according to the following requirements: (1) easy to process and high mechanical strength at high temperature; (2) maintaining stable quality; (4) The resistance change under high temperature is small.