Analysis of heat treatment furnace
TIME：2015-3-23 AUTHOR：xiaoyu CLICK：4449次
Heat treatment furnace working principle is: the heat treatment of metals is to put a metal workpiece in a certain medium is heated to a proper temperature, this temperature and keep some time after and cooled at different speed, by changing the metal surface or internal organizational structure to control the process. The heat treatment of metals is to put a metal workpiece in a certain medium is heated to a proper temperature, this temperature and keep some time after and cooled at different speed, by changing the metal surface or internal organizational structure to control the performance of a process.
Metal heat processing is one of the important process in mechanical manufacturing, compared with other processing technology, heat treatment generally does not change the shape of the workpiece and the overall chemical composition, but by changing the microstructure of the workpiece internal, or change the chemical composition of the workpiece surface, giving or improving the workpiece performance. Its characteristic is to improve the intrinsic quality of the workpiece, which is generally not visible to the naked eye.
In order to make the metal workpieces have the mechanical properties, physical properties and chemical properties, the heat treatment technology is often essential except for the reasonable selection of materials and various forming processes.. Iron and steel is the most widely used material in mechanical industry. The microstructure of steel is controlled by heat treatment. So the heat treatment of iron and steel is the main content of heat treatment.. In addition, aluminum, copper, magnesium, titanium and its alloys can also change their mechanical, physical and chemical properties by heat treatment to obtain different performance..
Heat treatment equipment is the equipment for annealing, tempering, quenching, heating and other heat treatment processes of the workpiece.
(1) bell type furnace
A periodic working heat treatment furnace for heating of the heated material in the hood.. Mainly used for sheet pile or steel coil annealing furnace, usually composed of cover, the inner cover and the stove. The heated object placed inside the hood (Ma Fuzhao), the inner cover and the outer cover between the heating. General to the cover pass through controlled atmosphere. Heating, heat preservation, slow cooling process is complete, the hanging go cover, plate pile or steel roll will cover cooling; after being cooled to a given temperature, remove cover, plate or steel coils in air cooling and discharging. Figure 1 is a bell type annealing furnace processing sheet piles, install the burner on the stove. Cold rolled steel coils of a batch processing has two kinds of single pile and pile type, multi stack can be in a rectangular furnace put 2 ~ 8 duo steel roll, each stack are respectively buckled on individual round cover. A circulating fan is installed in the lower part of the inner cover to strengthen the control atmosphere and the convection heat transfer between the steel coils..
(2) roller hearth furnace
Transport of heat treated wood furnace roller, along the entire length of the stove every certain distance to install a root rollers, materials in the roller running, in the roller above and below the furnace can arrangement of the burner heating (Figure 2). Roller roller ring (with disc and ring) peace and two, the former is only used for heating plate, the latter for heating plate, steel, pipe and bar. The roller outer sleeve material is heat-resistant steel, or silicon carbide. The furnace (1150 ~ 1000) with high temperature and heat - water - heat - resistant steel - furnace roller with heat - cooling - shaft, or the furnace roller with an insulating liner. In order to prevent furnace roll bending, under the high temperature working roller must be spinning; when the stove air burning or no material, also want to at low speed per minute from 0.5 to 1.5 weeks speed swing or rotation. The roller hearth furnace is heated by both sides of the material, and is heated faster and more evenly. It is widely used in heat treatment process of normalizing, annealing, quenching and tempering..
(3) chain furnace
A conveyor belt type heat treating furnace, taking the chain as the conveying belt to carry the workpiece. For thin slab rolling heating and sheet normalization processing chain furnace, chain is generally located in the groove under the stove, link is arranged between the useful heat resistant steel and heat resistant cast iron manufacturing furnace claw ", placed above the thin slab or plate. Generally, the steel can be heated to 900 degrees, and the furnace length will not exceed 25 m. In the non-ferrous metal processing, machinery, enamel and other industries, also commonly used chain furnace for various workpiece heat treatment and casting drying, etc.. The chain of some chain furnace installed in stove top or side, through the gap to the hook or rod extends into the furnace, to the suspension of the workpiece. Some low temperature heat treatment furnace put the chain in the furnace, the workpiece directly on the chain heating.
(4) traction type heat treatment furnace
Widely used in cold rolled strip tin, zinc and silicon steel, stainless steel continuous heat treatment, in recent years, also used for deep red tape annealing. The traction furnace can be divided into two types: horizontal and vertical.. Horizontal (straight - horizontal furnace) and multi - (folding oven) - vertical (vertical furnace) and multi - (tower - type furnaces).. Traction type heat treatment furnace than bell type annealing furnace with short construction period, less land occupation, product quality good advantage (smooth, uniform) and high degree of automation, but the equipment is complicated. Tower furnace traction speed of the strip can be as high as 10 metres per second, with radiation pipe or electric heating, control components, processing temperature is 700 ~ 980 DEG C.
(5) wire lead quenching furnace
Patenting from the English transliteration of the bake blunt oven, is a traction type heat treatment furnace, for wire in the lead trough in the isothermal quenching of heating. The heating temperature is 870 ~ 970. The furnace muffle type, fire type and electric direct heating type three. In addition, the heat treatment furnace is used to grow well, the workpiece and wheel tyre. Bath furnace is widely used in need of uniform, rapid heating heat treatment and prevent oxidation and decarburization of small parts.