Vacuum Oil/Gas Quench Furnaces (VOQ)

Vacuum Oil/Gas Quench Furnaces (VOQ)

The two-chamber design of the VOQ vacuum furnace  can meet all of your changing application needs. Depending on process requirements, the user can select quenching with either oil or inert gas.

The versatile VOQ vacuum furnace  is ideal for incorporation of heat treatment can also handle a multitude of thermal processes for a variety of materials including:

Hardening with gas or oil quench
Carburizing with gas or oil quench
Carbonitriding with oil quench
Brazing
Annealing
Solution annealing
Aging/stress relieving
Tempering

Vacuum furnace works

Vacuum furnace works

Vacuum furnace generally by the host, furnace, electric devices, sealed furnace shell, vacuum system, power supply system, the furnace temperature control system and truck components. Sealed furnace shell welded carbon steel or stainless steel, removable parts joints sealed with vacuum sealing material. After the furnace shell to prevent thermal deformation and metamorphism heat sealing materials, furnace shell is generally cool with water or air cooling. Hearth furnace located sealed envelope. According furnace use, installed inside the furnace heating elements of different types, such as resistors, induction coil, and the electron gun electrodes. Metal smelting furnace built with vacuum furnace crucible, some also equipped with automatic pouring device and the loading and unloading of robots. Vacuum system consists of vacuum pumps, vacuum valves and vacuum gauges and other components. 
Vacuum furnace that works by extracting vacuum, forming a nearly destroy ocean air low pressure environment, and then use the water at low pressure (less than atmospheric pressure) low boiling to produce steam, condensation heat transfer by way of soft drinks heat output operates on the principle of work.
Compared to other types of furnaces, vacuum furnace has several significant advantages: no pollution to the environment, without the need for waste treatment; the use of high quality insulation material insulation walls and barriers, low energy consumption and therefore energy savings significantly; high precision temperature control and so on.

Vacuum Tempering Furnace

Vacuum Tempering Furnace

Vacuum Tempering Furnace is applied for heat treatment processes(quenching and tempering and bright atmosphere) of metal materials such as high speed steel, tool steel, tool steel, titanium alloy and parts of various materials under vacuum condition with a fast-cooling system, which is high efficiency.
The control system was controlled by PLC, temperature was controlled by intelligent temp controller, accurate control, high automation. User can choose auto or manual undisturbed switching to operate it, this furnace has abnormal condition alarming function, easy to operate.
Environmental protection performance has been improved, maintenance cost saving, energy cost saving.

The partial pressure in the application of the vacuum heat treatment

        The partial pressure in the application of the vacuum heat treatment

1. The choice of gas filling back 
Vacuum protective atmosphere heat treatment method to the choice of gas filling. When using the partial pressure of heating vacuum heat treatment back filling gas should choose the neutral or inert gases, high purity hydrogen, helium, nitrogen and argon gas, such as common gases, four gas cooling speed from fast to slow, in turn, for hydrogen, helium, nitrogen and argon. In the air as the cooling speed of 1, the hydrogen, helium, nitrogen, argon and air cooling speed ratio of 7, 6, 0.99, 0.7, respectively. Under any pressure, hydrogen has the maximum heat transfer capacity and maximum cooling speed, can be used for graphite as heating and insulation components of vacuum furnace. But, for high carbon steel grade, the cooling stage of high temperature (above 1050 ℃) may cause slight decarbonization; Used for high strength steel has the risk of hydrogen embrittlement. Using hydrogen as coolant supply system should be sealed and reliable, complete cooling after operation, should be timely discharge of hydrogen, and filling the nitrogen, may open the oven door, otherwise, has caused the risk of explosion.
Helium has the highest price. Because it have some cooling capacity under low pressure, so, generally in 1 x 104 pa under air pressure is used.
Nitrogen is the most commonly used gas, also the cheapest. In just under atmospheric pressure under the pressure forced circulation cooling, cooling intensity value can rise about 20 times. Within 200 ~ 1200 ℃, nitrogen for ordinary steel in neutral, the titanium alloy, stainless steel, high temperature alloys such as an activity, if under the nitrogen partial pressure vacuum heating and cooling, the surface has Cr2N performance deteriorated, causing surface, namely the increase of tensile strength, reduction of area decreased, corrosion resistance will be affected by a certain. So is unfavorable use nitrogen.
Argon is common, cheaper than helium, but more expensive than nitrogen, in the case of unfavorable use nitrogen, such as stainless steel, high temperature alloy and titanium alloy vacuum heating and cooling, you need to use the argon gas.
2. The choice of the vacuum degree
After vacuum heat treatment parts surface brightness and vacuum degree of heating, the heating temperature and other factors are closely related. In a certain temperature, vacuum heat treatment parts of the surface brightness, along with the increase of vacuum degree, as shown in figure 1. However, when the heating temperature is higher, causes a high vapor pressure of the alloy elements evaporation, parts of the surface brightness will fall.

Vacuum Annealing Furnace

Vacuum Annealing Furnace

Vacuum Annealing Furnace is applied for annealing and aging treatment of a variety of alloy materials, devices (tungsten, molybdenum, niobium, copper alloy, etc.), magnetic materials, electrical steel, magnetic alloy, stainless steel, heat-resistant alloys, copper and its alloys, hydrogen storage alloy, active and hard molten metal. It can also be used for vacuum sintering of magnetic material, diamond, hydrogen storage material reduction. The control system was controlled by PLC, temperature was controlled by intelligent temp controller, accurate control, high automation. User can choose auto or manual undisturbed switching to operate it, this vacuum furnace has abnormal condition alarming function, easy to operate.
Environmental protection performance has been improved, maintenance cost saving, energy cost saving.

Numerical analysis of vacuum furnace

Numerical analysis of vacuum furnace

Magnesium smelting process conditions in order to improve and overcome many problems, funded by the Science and Technology Department of Ningxia, specialty materials laboratory material, Xi'an University of Science and west of the country to undertake special projects, self-invented the heat-type electric vacuum with metal magnesium vacuum smelting furnace technology. The technology uses a secondary energy - electric heating, heat from the reactor material inside, to avoid problems caused by pollution from fuel combustion, it is also to avoid the traditional material reduction tank many restrictions on the reduction process. In this paper, the mechanism of new technologies, core temperature vacuum furnace equipment research.
According vacuum furnace should be consistent with the heat transfer equation in cylindrical coordinates heat transfer equation, since the entire course of the reaction, the temperature of the diffusion furnace is the radial distance r and time t, so only three variables temperature T-T ( r, jealousy, f), namely two spatial variables and a time variable. Geometric zone temperature is at the site of a circle, when the thermal conductivity of the material is constant within the annular region Differential thermal stability is: where: T is transient temperature, ℃; t is the reaction time, s; A is The average thermal conductivity of the reaction material, W · m-1 · ℃ ~, can be treated as a constant; p is the average density of the reaction materials, kg / m3; G reaction expected average specific heat, J · kg_1 · ℃ 1; roar of the furnace core internal heat source strength (ie surface load furnace core), W · m ~, do constant process. R is the radius of the furnace, the vertical angle.