2017年4月27日星期四

Brazing technology of classification and what are the advantages?

Brazing technology of classification and what are the advantages?
Brazing is one of the three welding method, including fusion welding, brazing and bonding of the three. Brazing process is mainly to use than the weld metal of low melting point metal solder, and then heated to a temperature higher than the weldment and filler metals solder, below the melting temperature of the weldment, then using liquid solder wetting welding pieces of metal, fill the joint clearance and mutual diffusion and base metal, so as to realize a method of connecting the weldment. So compared with other welding methods, brazing process advantages what?
1, when soldering, solder melts, and weldment won't melt, and the temperature of the welding with the different choice of solder, and at room temperature to nearly large areas of the parent metal melting temperature change inside. In order to avoid the base organizations, as well as the change of the performance, you can choose to brazing filler metals, which have lower melting point and welding is no choice.
2, at the time of brazing, welding is often a whole heating or around the brazing seam for uniform heating of large area, therefore, relative distortion of welding and brazing welding head are much smaller than welding residual stress, it is also to ensure the precision of welding.
3 are heavily dependent on liquid filler metals, brazing seam automatically fill the gap after frozen, so as long as the solder, flux and brazing methods selection of good, can mass or many brazing seam welding at the same time or continuous brazing, productivity is very high. In the process of brazing rarely because of the accessibility of the weld structure, and open sex.
4, because the soldering reaction only in parent material of a few microns and even the following interface to dozens of micrometers, so, generally does not involve the deep structure of parent metal, and therefore, more suitable for dissimilar metal stents, and even nonmetallic and nonmetal, the connection between the metal and nonmetal, it is can't do welding method.
5, brazing seam strength and heat resistance were lower than the base metal, and in order to make up the lack of strength, often by increasing the overlap area to solve the problem, so the braze welding head will be more samples of the lap joint methods to increase the weight of the structure, therefore, is more brazing materials.

2017年4月6日星期四

The vacuum brazing furnace main

The vacuum brazing furnace main 
It is mainly used for aluminium parts brazing production under the protective atmosphere. Mainly include solder spray machine, electric heat drying furnace, brazing furnace, water-cooled air cooling device, the atmosphere control system and automatic control system, etc. Suitable for parallel flow condenser, cascading evaporator and car tank mass production of aluminum alloy heat sink, etc.
Main features:
1, spray device has the advantages of simple structure, easy to use.
2 in furnace, drying furnace circulating wind speed is high, large heat capacity, ensure the workpiece drying thoroughly.
3, brazing furnace reasonable partition fine, high precision temperature control, furnace temperature uniformity is good, energy-saving effect is remarkable.
Production line 4, the consummation control system integration, intelligent, control, alarm, protection system to ensure the safe and reliable operation of the production line.
More than 5, range, high precision of oxygen analyzer for real-time accurate measurement in furnace atmosphere provide advanced means.

2017年3月29日星期三

Understand the high requirements of the high temperature vacuum furnace

Understand the high requirements of the high temperature vacuum furnace
High temperature vacuum furnace ironmaking automation is designed to make production process optimization, produce stable quality products and improve the process operator working conditions, this requires the technical and economic aspects of productive rationalization measures, in the process of ore smelting discount, physical and chemical changes very difficult to control the difficult measurement.
More and more high mechanization degree of high temperature vacuum furnace, vacuum environment was does not have other forms of sintering (when the furnace vacuum degree is 1.3 * 10-1 PASCAL, remaining in the furnace gas purity argon 99.99987%); Vacuum sintering can make material before a liquid particle oxidation film completely ruled out, so as to change a good wettability of the liquid with carbide phase, to improve the alloy organization structure, improve the performance of alloy. Due to the vacuum press billet pore reduced the amount of gas in steel rolling workshop push by the steel type heating furnace of continuous development to all kinds of stepping type furnace, roller hearth furnace, furnace, chain furnace, etc.
Some within the chamber furnace heating shaped blank in the past, now change in annular furnace heating, productivity had the very big enhancement. The use of the electronic computer, the stove from loading assumed, paragraphs in the furnace temperature control, fuel and air traffic control, automatic control, furnace pressure until the steel material on time and discharging program operation, are given by computer control values, and be able to adopt the optimal control of the furnace condition, on the temperature of the steel material and the temperature difference at very accurately.

2017年3月28日星期二

How to determine the cooling speed of vacuum brazing furnace parts

How to determine the cooling speed of vacuum brazing furnace parts
Weldment cooling is done at the end of the soldering heat preservation, but the rate of cooling is have effect on the quality of the joint. Cooling speed too slow, may cause the grain growth of parent metal, solder with parent metal interaction time growth, leading to excess of parent metal to dissolve in the solder, produce corrosion defects; To speed up the cooling speed, which is beneficial to refine brazing seam organization, thus improve the joint strength; But cooling speed too fast, may make the welding crack due to excessive internal stress formed, may also be due to the brazing seam rapid solidification doesn't make the gas evolution and formation porosity. Therefore specific to determine the cooling speed, must be combined with weldment size, by synthetically considering all kinds of factors such as parent material types and solder.

2017年3月23日星期四

The characteristics of the vacuum furnace design

The characteristics of the vacuum furnace design
Vacuum furnace design adopts many new and high science and technology, to introduce the following vacuum furnace design features:
1, energy conservation and efficient
Vacuum furnace designed by high vacuum furnace technology, boiler operation state is vacuum, therefore the boiling point is lower, so the heat exchange performance is better, so that improve the efficiency of the boiler and save a lot of energy.
2, safe and reliable
Vacuum furnace negative pressure operation, there can be no heat medium in the vacuum state, the danger of explosion. Furnace with the heat medium water, there is no dry vacuum furnace. Multiple automatic protection device for the vacuum furnace design, make its safety performance is greatly enhanced.
3, long service life
Vacuum furnace of the heat exchanger is stainless steel material, not corrosion at high temperature, it is impossible to scale, the service life of 20 years.
4, rich models
Vacuum furnace design models is very rich, there are horizontal, vertical, gas, fuel and other models for customers to choose.
5, easy installation
Streamline shape when vacuum furnace design, vacuum furnace units are generally smaller volume, easy to transport and install.
Six, pay attention to environmental protection
Vacuum furnace design adopts high-performance burner and flame structure, combustion is very sufficient, the indicators all meet the national discharge standard.
7, exemption formalities
Does not need pressure window approval vacuum furnace, also does not need to be careful, when workers also do not need to take relevant work permit.
8, intelligent control,
Vacuum furnace design adopts touch screen display, virtual buttons, Chinese graphic display, fault self diagnosis instrument as well as the man-machine dialogue.

2017年3月20日星期一

Good performance of vacuum brazing furnace

Good performance of vacuum brazing furnace
Vacuum brazing furnace to adhere to the excellent soldering quality depends on the function of the vacuum unit. Vacuum pump often need to pay attention to don't want to think "permanent don't you shut down, it will run forever." If be vacuum unit maintenance at that time, on weekends and holidays shutdown, more economical to do so. Otherwise, if still idling at the weekend, mechanical pump is stuck and hard to start again. Let's test results show that this method can save a lot of electricity. Because of the lack of cooling water may overheat, form a mechanical pump overheating, and announced the noise.
The best water temperature of 140. (60 ~ 150 F a 6 ℃), with simple equipment to pump oil filter, once a week to check the oil level and take the sample, by feeling and appearance check the quality of the oil. A few years ago, we have found that the mechanical pump with excellent oil is more economic. Excellent oil cost is over more than three times of industrial oil, and adhere to the pump qing jie time is five times the sustainable. Once every three months should replace live door and spring. Stainless steel spring longer life spans.

2017年3月3日星期五

Vacuum furnace don't like to "eat" what material?

Vacuum furnace don't like to "eat" what material?
Vacuum furnace is widely accept metal materials, but because of many reasons resulted in the vacuum furnace is unable to process the materials, such as in the technical requirements, need to cost, there are some difference on the craft, vacuum furnace that what kind of material is not "eat"?
Carbon steel, carbon steel price under other steel products, and finished product price is not high also, if there is no allowance is not highly profitable materials or materials processing, forced from cost to consider, or do not use vacuum furnace is better, because the cost of the vacuum furnace is far higher than that of carbon steel prices, really isn't worth while.
N elements: using high temperature materials processing of n elements, not only can produce harmful products material and the sensitivity of the high temperature of n elements is too high, alloying elements using vacuum furnace processing in order to prevent metal material to send out at high temperatures, so generally will be under the condition of high temperature high purity nitrogen partial pressure, cooling using nitrogen charging way, so unfavorable use vacuum furnace.
Special materials: some special material in order to achieve the result that you want to use high temperature processing, some materials need to obtain bainite, some are to get good mechanical properties, isothermal quenching can be used to reach the effect, but the vacuum furnace to achieve some special material of hot working, although with high-pressure gas quenching vacuum furnace for high hardness for Ms points under cold temperature speed faster, will be large deformation effects.