Horizontal heat treatment furnace is a comprehensive technology combining heat treatment technology and vacuum technology, which mainly refers to all or part of the heat treatment process in the vacuum state. The thermal efficiency of the vacuum heat treatment furnace is relatively high, which can realize the work of rapid cooling or heating up, as well as the situation of no decarburization, no oxidation and no carburization. In addition, it can also remove the scale on the surface of the treated workpiece, and play the role of degreasing and degassing, so that the surface of the treated workpiece can achieve the effect of bright purification Fruit.
Common types of horizontal heat treatment furnace:
Commonly used heat treatment furnaces include box type resistance furnace, well type resistance furnace, gas carburizing furnace and salt bath furnace.
1. Box type resistance furnace: its working principle is to use the current to heat through the electric heating elements arranged in the furnace, and to heat the parts through the current and radiation. It is a widely used heating equipment in heat treatment workshop. It is suitable for annealing, normalizing, quenching, tempering and solid carburizing of steel and non steel materials (non-ferrous metals). The utility model has the advantages of simple operation, accurate temperature control, the introduction of protective gas to prevent the oxidation of parts during heating, and good working conditions.
2. Well type electric resistance furnace: the working principle of well type electric resistance furnace is the same as that of box type electric resistance furnace. Its furnace mouth is upward and its shape is like a well. There are three kinds of furnace commonly used: medium temperature well furnace, low temperature well furnace and gas carburizing furnace. The shaft type resistance furnace uses crane to lift parts, which can reduce labor intensity, so it is widely used.
The medium temperature well furnace is mainly used for quenching, annealing, normalizing and other heat treatment of long dry parts. Its working temperature is 950 ℃. Compared with the box furnace, the well furnace has better heat transfer, the top of the furnace can be equipped with fans, so that the temperature distribution is more uniform, and the vertical placement of slender parts can overcome the bending deformation caused by self weight when the parts are placed horizontally.
3. Salt bath furnace: salt bath furnace is a furnace type that uses molten salt as heating medium. The salt bath furnace has the advantages of simple structure, convenient manufacture, low cost, good heating quality and fast heating speed, so it is widely used. However, when heating to the salt bath furnace, there are such processes as binding and clamping of parts, complicated operation, high labor intensity, poor working conditions, and long heating up time when starting. Therefore, salt bath furnace is often used in small and medium-sized parts with high surface quality requirements.
Horizontal heat treatment furnace has the following three characteristics:
1. Installed with water-cooling device, the cover, door and electric heating elements of horizontal heat treatment furnace are missing, which are all working in vacuum and heated state. Therefore, if you want to work under such a * * condition, and ensure that the structure of the horizontal heat treatment furnace is not damaged or deformed, etc., then each component should be installed with a water-cooling device according to the specific situation, so as to ensure the normal operation of the horizontal heat treatment furnace.
2. Most of the insulation and heating materials can only be used in vacuum. Because the materials for heat insulation and heating are used in vacuum, the requirements for vapor pressure, high temperature resistance and radiation of these materials will be improved.
3. The vacuum sealing is strict, and the metal parts are all carried out in the closed vacuum furnace during the heat treatment, so it is necessary to ensure the working vacuum of the vacuum furnace. In order to ensure the vacuum performance of the vacuum furnace, it is necessary to follow a principle when designing the vacuum furnace, that is, the furnace body must be welded with air tightness, and it is also necessary to make as few holes or no holes on the furnace body as possible, so as to reduce the probability of vacuum leakage.
On 2018-08-08 11:45:46
