Vacuum atmosphere furnace equipment must be used under what conditions

Vacuum atmosphere furnace equipment must be used under what conditions

1. Vacuum atmosphere furnace equipment must be used in the following conditions:
1) indoor use, environment temperature in - 10 ~ 40 ℃;
2) no more than 1000 meters above sea level;
3) environmental relative humidity less than 85% RH;
4) the environment without conductive dust, inflammable and explosive objects and gases, and serious damage to metal corrosive gas;
5) no vibration and turbulence,
2. Check the circuit connection parts contact are in good condition.
3. The proper use of standardized operation, the highest temperature of 1200 ℃ can't use for a long time, overheating, overload operation of avoid by all means, keep a sudden rise in moderate quench the blackout, so as not to damage the furnace and heating wire.
Contains 4. It is strictly prohibited to high moisture, volatile matter, organic matter and other artifacts directly into the furnace heat treatment.
5. It is strictly prohibited to high temperature melting material such as metal, glass, in the absence of crucible loaded into the furnace under the condition of heat treatment.
6. Always check the electric heating element, in case of aging, fracture, short circuit should be timely repair and replacement.
7. Often remove the scrap material in furnace dust particles and fallout, etc, in order to keep clean inside the furnace.
8. It is strictly prohibited to overload the use of this equipment, so as not to cause damage of equipment structure.

The characteristics of the vacuum furnace temperature field formed

The characteristics of the vacuum furnace temperature field formed

Vacuum furnace heating elements generally assumes the circular layout. Relative average furnace, vacuum heating only the heat transfer of radiation, conduction and convection; The vacuum heat conduction, convection and radiation, three ways of convection and conduction depending on the pressure and with ordinary furnace (normal pressure).
Pressure is less than 1 x 105 pa (absolute pressure, ordinary furnace approximation of working pressure), the convection and conduction effect is less than ordinary furnace; Working pressure close to the vacuum (pa) 2, the convection and conduction effect basic does not exist, workpiece temperature is slow, especially below 600 ℃ heating, heating more slowly, the temperature of the workpiece temperature thermocouple temperature control has certain hysteresis.
The vacuum furnace temperature uniformity measurement is different from ordinary furnace, when measuring the need to guarantee the normal work of the furnace under the condition of vacuum and pressure rise rate, can correct determination of furnace temperature. Because, unlike ordinary furnace, vacuum furnace heat transfer of actual temperature measurement process shows that the control thermocouple temperature at the beginning of the heat preservation and the effective heating area measuring thermocouple temperature difference is bigger. In vacuum condition, temperature deviation in the normal heat preservation time of the effective heating area can reach + / - 5 ℃, meet the needs of the process.

Little knowledge of vacuum sintering furnace

Little knowledge of vacuum sintering furnace

Vacuum sintering furnace in the furnace chamber within a particular space using vacuum system (by the vacuum pump, vacuum measuring device and vacuum valve components such as carefully) substances out of furnace cavity part, making furnace chamber pressure is less than a standard atmospheric pressure, so as to realize a vacuum furnace cavity space, that is the vacuum sintering furnace.
1) completely eliminates the oxidation and decarburization on the surface of the workpiece during the process of heating, clean surface without metamorphic layer can be obtained. That only when grinding mill side of cutting tools (such as twist drill grinding after make direct exposure to edge) of the decarburization layer of the grooved surface cutting performance greatly improved relations.
2) on the environment pollution-free, "three wastes" treatment is not required.
3) obviously improve the temperature measurement, the monitoring precision. Indicated value of thermocouple temperature and furnace temperature reached plus or minus 1.5 ° c. But in different parts of a large number of artifacts in the furnace temperature difference is bigger, if USES the rarefied gas forced circulation, can still be controlled within + / - 5 ° c temperature difference.
4) high degree of mechanical and electrical integration. Increase in the temperature measurement and control accuracy, on the basis of the workpiece moving, pressure adjustment, power adjustment, etc all can set programming in advance, according to the steps to implement the quenching and tempering. 5) energy consumption significantly below the salt bath furnace. Modern advanced vacuum furnace heating chamber is made of high quality insulation material of insulation walls and barriers, electric energy can be highly focused on indoor heating, energy saving effect is remarkable.

Vacuum furnace large analytical performance advantage is obvious

Vacuum furnace large analytical performance advantage is obvious

Vacuum furnace, just as its name implies, it operates within the furnace is in a vacuum, so to avoid the defect of the many other each type coal stove.
1, completely eliminates the oxidation and decarburization on the surface of the workpiece during the process of heating, clean surface without metamorphic layer can be obtained. That only when grinding side grinding tool cutting performance greatly improved relations.
2, on the environment pollution-free, "three wastes" treatment is not required.
3, obviously improve the temperature measurement, the monitoring precision. Indicated value of thermocouple temperature and furnace temperature reached plus or minus 1.5 ° c. But in different parts of a large number of artifacts in the furnace temperature difference is bigger, if USES the rarefied gas forced circulation, can still be controlled within + / - 5 ° c temperature difference.
4, high degree of mechanical and electrical integration. Increase in the temperature measurement and control accuracy, on the basis of the workpiece moving, pressure adjustment, power adjustment, etc all can set programming in advance, according to the steps to implement the quenching and tempering.
5, significantly below the salt bath furnace energy consumption. Modern advanced vacuum furnace heating chamber is made of high quality insulation material of insulation walls and barriers, electric energy can be highly focused on indoor heating, energy saving effect is remarkable.

Vacuum furnace production process can be divided into two broad categories

Vacuum furnace production process can be divided into two broad categories

Vacuum furnace production process can be divided into two broad categories: electrolytic method and thermal reduction process, the former USES the vacuum furnace chloride as raw material, the latter using dolomite ore as raw material, etc. Using electrolytic process conditions is the place where power rich and low price. At present only in qinghai and vacuum furnace factory using electrolysis refining vacuum furnace. Under the influence of raw materials, and other factors, our country most of the vacuum furnace factory adopts silicon thermal vacuum furnace smelting reduction method. The method using ferrosilicon as reducing agent, this method is compared with the other vacuum furnace smelting process, the technological process is simpler, less infrastructure investment, factory fast; The production process does not produce harmful gases, slag (2 ca0 si02) for production of cement or fertilizer raw materials; Silicon metal vacuum furnace thermal vacuum furnace smelting process of high purity, large economic benefit. But the size of the reduction pot was numerically simulated small, single canned capacity is low, productivity is low, the thermal efficiency is not high, continuous production, labor intensity is big. Tank outside the solid, liquid or gaseous fuel heating, smoke take away a lot of heat, not only greatly reduces the heat utilization rate, and incomplete combustion of smoke caused serious pollution to the environment.

Vacuum pressure sintering furnace

Vacuum pressure sintering furnace

In vacuum pressure sintering furnace this equipment, sintering material under high temperature is also subject to mechanical stress and the effect of vacuum, can be used in the sintering density after casting products. General powder material filling in the graphite mold, mechanical pressure by 700-1500 mn/m3, and heated to 2500 ℃ in the vacuum. Mold by direct current heating, indirect heating.
Vacuum pressure sintering furnace is mainly used for sintering is the density of the material with high temperature gas reactions billet, such as oxide, carbide and boride gas after sintering material can reach very high density, general density is greater than the theoretical value of 95%, and with high purity. Graphite resistor and graphite mould in the vacuum operation of weight loss is minimal. Vacuum hot pressing sintering is at the same time in the compaction process and utilization of high pressure, temperature and time, and many other parameters to control the quality of the sintered body.

Vacuum sintering furnace working principle and structural function

Vacuum sintering furnace working principle and structural function

Vacuum sintering furnace is in a vacuum environment to be heated objects in protective sintering furnace, its heating mode is more, such as resistance heating, induction heating, microwave heating, etc. Vacuum induction furnace is heated objects to make use of induction heating protective sintering furnace, can be divided into the power frequency, medium frequency, high-frequency, such as type, can be ascribed to a subclass of vacuum sintering furnace. Vacuum induction furnace is under vacuum or protective atmosphere conditions, using the principle of intermediate frequency induction heating make hard alloy tool bit and all kinds of metal powder compacting sintering of complete sets of equipment, is for hard alloy, metal dysprosium, designed in the industrial production of ceramic materials.
For more than a, main structure and the composition structure under vertical and discharging. Its main composition is: the furnace body, vacuum system, water cooling system, pneumatic system, hydraulic system and front-rear institutions, base, workbench, induction heating device (tungsten heater and advanced thermal insulation material), into the electric device, medium frequency power supply and electric control system, etc.
Second, the main function after vacuum filling the hydrogen gas protection, control of furnace pressure and state of sintering atmosphere. Available optical fiber infrared radiation thermometer and armoured thermocouple temperature measurement (0 ~ 2500 ℃), and through the intelligent temperature control after comparing with the setup program, select the execution state feedback to intermediate frequency power supply, automatic control temperature and heat preservation program.
Tungsten, main principle and USES vacuum induction furnace is after vacuum filling hydrogen protection condition, by using the principle of intermediate frequency induction heating, the high temperature of tungsten crucible in the winding, by heat conduction to work on, suitable for scientific research, military units for hard metal such as tungsten, molybdenum and its alloy powder sintering molding.

How to maintain the vacuum sintering furnace

How to maintain the vacuum sintering furnace

Vacuum sintering furnace is widely used in ceramics, silicon carbide, carbide materials, electroplating mold material and vacuum sintering graphite purification processing, want to undertake maintenance in the use of vacuum sintering furnace, only to do maintenance can be used more for long.
1, equipment four distribution cabinets clean operations.
2, such as mesh belt for the thimble mesh belt, please use sand paper burnish thimble side, in order to prevent the scratch of cell, if it is a diagonal mesh belt, baking at low speed in the speed of 100 case, to remove organic matter.
3, such as tube infection, organic matter, please be careful with alcohol cotton swab or non-woven fabrics.
4, inside the cavity clean homework (needs pay attention to the porosity have without block).
5, organic rows and heat cleaning operation (including facility and equipment, as well as the equipment of oil cigarette case), please use the organic matter on the alcohol cleaning equipment, etc.
Sealing structure on 6, furnace, vacuum system and other components when disassembling, alcohol or gasoline clean and after dry, apply vacuum grease on it again.
7, the transmission is not allowed if there is a limit, control failure, screens etc. Phenomenon, should immediately stop, don't force, so as not to damage parts.
After 
8, vacuum sintering furnace, the furnace, furnace must remain below 66.5 LPA vacuum degree.
9, vacuum pump, valve, measuring instruments, thermal instrumentation, electrical components, such as accessories, must be in accordance with the technical specifications of the products use, repair and maintenance.
10, maintenance operation should be performed under the condition of without electricity. If under the condition of charged for repair, must by the professional maintenance personnel for repair, at the same time to ensure the absolute safety of person and equipment.
11, vacuum sintering furnace aluminum plate spot welding machine mechanical transmission parts should be lubricated periodically or oil changes and maintenance.

What is the importance of vacuum sintering furnace cooling system?

What is the importance of vacuum sintering furnace cooling system?

Vacuum sintering furnace is electric heating element near the vacuum heating furnace. Vacuum furnace cooling system is an important part of vacuum furnace. Cooling water should maintain smooth, otherwise the temperature rise caused downtime. This is vacuum furnace work often neglected problems When no one management major damage may result in vacuum furnace.
Molybdenum vacuum furnace heating after long time use will harden, shrinkage, drop, lodging first lap, after fusing (melting) wait for a phenomenon. To make the vacuum furnace heating wire is necessary strength at high temperature, prevent hardening, collapsed or droop, first to design the structure of the vacuum furnace heating wire size, such as spiral wire, pay attention to the heating element bending diameter, pitch and screw pitch diameter, etc. The heating body is going to loose by vacuum furnace insulation lining, 95 ceramic on insulation lining is put aside, leave the expansion space. Shelve location should be suitable for, one is in commonly 100 ~ 100 mm, and can prevent resistance wire to lie prone on strong hook. Also should avoid furnace silk direct contact between each other (short circuit), usually to pad spacer.
Deal with cooling water with biological decomposition chemical auxiliary method, the purpose is to keep the minerals in suspended state, reduce the rubber tube, coil and water jacket in sediment accumulation, to make the water clear. This generally adopts an automatic device to complete, it can monitor the conductivity of the water, automatically added chemicals, wash water, add fresh water. Cooperate with auxiliary steam filtration system, this method can guarantee the pH of the water control, to prevent redundant mineral deposits in the cooling water system. After the system work stable, at least once a month for the water quality test case after processing or owed.
Vacuum tempering furnace shell and the heat exchange equipment material test sample should also be placed in water system, a yearly weight loss test to check the effect of the processing. Coil of diffusion pump cooler must pay special attention to. Should be check regularly. If blocked, diffusion pump will be overheating and loss of function, but also further cause the diffusion pump heater burning, cause of expensive, time-consuming repairs. When snake-like cooling water pipe plug, water will disconnect with water and the drainage and use compressed air to blow or wash with dilute acetic acid solution.

In the vacuum furnace temperature distribution

In the vacuum furnace temperature distribution

Graphite rod arrangement method on either side of the heating element is decorated in the heating chamber, especially suitable for high vacuum furnace. In a high vacuum atmosphere, thermal radiation produced by on both sides of the heating element area artifacts can be uniformly heated. When the temperature at 400-1300 ℃, heating area each point temperature difference of + / - 5 K. In the '60 s, before the temperature control has been one of the main problems in the heat treatment technology. Because later adopted the technology of electronic temperature control, this problem has been resolved. At present, from the point of view of the temperature distribution, the precision of the hotspot temperature distribution is an important problem.
We almost always preferred to obtain uniform temperature on the structure can guarantee the hotspots, as for temporarily due to some reason make the hotspot temperature uneven phenomenon will disappear with the extension of heat preservation time. On the other hand, the temperature is higher or lower hotspot makes it consistently throughout the harmful effects of heat treatment. Below we present in this fruitful, the temperature gradient is lower than 0.01 K/cm vacuum furnace structure. In addition to the vacuum furnace temperature uniformity, there are some other advantages. Consume less power, completely avoid the use of toxic materials, heating, smoke pollution to the environment to produce outgassing, perfectly solve the problem of the material surface oxidation or distortion. Because of these advantages have now made vacuum furnace heat treatment process of necessary conditions. Heat transfer in a vacuum From the point of heat transfer, vacuum play a dual role.

The five requirements of vacuum sintering furnace

The five requirements of vacuum sintering furnace

In order to guarantee the billet in the sintering process of powder forming dewaxing (lubricant or forming agent), reduction, sintering, alloying and densification, the need when sintering on the sintering temperature, protective atmosphere, ware transmission speed, heating and cooling speed and so on carries on the adjustment and control. Sintering furnace on the structure and function, therefore, should meet the following five requirements:
1. L have perfect dewaxing unit or dewaxing.
2. Has the air tightness, can isolate air outside the furnace and ensure smooth protective atmosphere in the furnace.
3. The temperature control of the paragraphs, paragraphs atmosphere is adjustable;
4. Continuous sintering furnace, with conveyer and the transmission speed is adjustable;
5. With fast cooling device, can be sintered parts rapid cooling to the temperature can be released.
The above is the five requirements, vacuum sintering furnace sintering furnace for sintering of powder metallurgy products of special equipment, its variety, reasonable selection and correct use of sintering furnace to ensure the quality of the powder metallurgy parts.

The effect of low pressure sintering furnace

The effect of low pressure sintering furnace

Low pressure sintering furnace is compatible with the dewaxing, vacuum sintering, low pressure sintering, low pressure processing, multiple functions such as sintering atmosphere. Mainly used for: pressure before products of low pressure sintering; The low pressure processing of sintered products; The carbon sintering pressure products.
Low pressure sintering's main function is to reduce the microscopic pore in cemented carbide. The porosity of the sintered body in the vacuum sintering stage has been eliminated. Microscopic pore pressure stage mainly eliminated.
Low porosity is an important symbol of high quality hard alloy, try to reduce the porosity in the cemented carbide in the production, is one of the main pursuit of carbide workers.
Carbide densification and capillary force, the wettability of liquid phase for solid phase and the surface tension of the liquid has a close relation with the associated, as in the process of sintering temperature, when a liquid phase, due to the capillary pressure, the liquid phase to the surface of WC mobile, because the liquid has good wettability to WC phase, liquid phase was attached to the surface of WC, because the surface tension of the liquid phase, driven by liquid package WC mobile, strong contraction occurs at this point. In WC mobile liquid package, in the process of contraction, exists in the gas is out of briquetting, due to the flow of the liquid phase, a part of the porosity of the sintered body is liquid closed, with the augmentation of the contract, enclosed within the pore pressure, when the surface tension is equal to or less than the pressure in the pore, closed pore preserved in the alloy, microscopic pore space.

Sintering zone of sintering furnace

Sintering zone of sintering furnace

Sintering belt sintering furnace vacuum induction furnace is under vacuum or protective atmosphere conditions, using the principle of intermediate frequency induction heating make hard alloy tool bit and all kinds of metal powder compacting sintering of complete sets of equipment, is for hard alloy, metallic dysprosium, designed in the industrial production of ceramic materials. High temperature hydrogen sintering furnace is the protective atmosphere of hydrogen under the conditions of reaction sintering furnace.

Discharge plasma sintering furnace

           Discharge plasma sintering furnace

Discharge plasma sintering because of strong impulse current between powder particles, so can produce a lot of beneficial to the effect of rapid sintering. Compared to the conventional sintering technology has the following advantages:
Sintering speed;
Improved ceramic microstructure and improve the performance of materials
Discharge plasma sintering is a combination of plasma activation, hot pressing, resistance heating, heating speed, short sintering time, sintering temperature, uniform grain size, low benefit to control the sintering of fine structure and get the material density is high, and has simple operation and high reproducibility and reliable safety, save space, save energy and low cost advantages.

Vacuum Induction High Temperature Graphite Furnace

Vacuum Induction High Temperature Graphite Furnace

Vacuum induction high temperature graphite furnace adopts the medium frequency induction heating principle in a vacuum or inert gas conditions by allowing the induction coil generating an alternating magnetic field, and then the graphite crucible and the induction coil generates eddy currents were self-heating.Graphite crucible is to produce high temperature and make radiation to the workpiece to reach the desired temperature.Applications :sintering process for carbon materials, carbon fiber and other composite materials graphitization. Feature :
1.High automatic, it can be fully automation with the furnace model simulation display and real-time display device when running. It can be equipped with PLC controller and human-machine interface control system.
2.Very safe, using PLC to achieve security chain, with sound-light alarm when over-temperature, sensor burnout, over pressure of furnace and water, water flow, water temperature is too high .
3.It can be equipped with a built-in or external fast-cooling system,improving the working efficiency
4.Advanced temperature, vacuum detection instruments and sensor components to ensure reliability of the equipment
5.Energy-saving, special made coil and insulation structure, power output stability, high electrical efficiency.