How does vacuum brazing work

Vacuum brazing furnace is a large Bai type heat treatment equipment, which can carry out vacuum brazing, vacuum annealing, vacuum aging and other processing.

Several different programs can be programmed to control and program hundreds of heat treatment curve points, which are divided into six zones: upper, lower, left and right, front and rear. There are multi-point and single point temperature recorders and over temperature protection devices.

The furnace temperature uniformity can be controlled within the constant temperature range. In addition, it is equipped with high-purity nitrogen and high flow forced cooling device.

radiator fin machine

The equipment has the advantages of large furnace loading capacity and high efficiency, and no supplementary process is needed for complex parts and parts with special requirements.

 

Purpose:

 

It is mainly used for vacuum brazing of aluminum products such as aluminum alloy heat exchanger, brazing of stainless steel, titanium alloy, cemented carbide, high temperature alloy, non-ferrous metal, vacuum tempering of high-speed steel, tool and die steel, bearing steel, stainless steel, aging and annealing treatment of non-ferrous metal, and vacuum brazing of stainless steel heat exchanger, oil cooler and stainless steel heat preservation cup.

 

characteristic:

 

1. The district heater is used to make the temperature uniformity in the heating area consistent.

 

It can keep the workpiece clean in vacuum.

 

Composition:

 

The vacuum system is mainly composed of vacuum chamber, pump system, control valves and heat exchanger. The pump system consists of mechanical pump, maintenance pump, roots pump and diffusion pump. The valve consists of front stage valve (butterfly valve), bypass valve (butterfly valve), maintenance pump valve (butterfly valve) and high valve (plate valve). Each valve is pneumatic valve, which is controlled by PLC pneumatic valve.

radiator core

The heating chamber is mainly composed of stainless steel heating chamber shell, stainless steel reflector, heater, ceramic insulator, water-cooled electrode, furnace bed, etc.

 

principle

 

When the vacuum system works, first start the mechanical pump, maintenance pump and diffusion pump (heating), and at the same time open the front valve and maintenance pump valve to vacuum the diffusion pump.

 

When the vacuum reaches a certain set value of the system, roots pump is started, bypass valve is opened and front stage valve is closed. At this time, vacuum chamber is pumped low. When diffusion pump is heated to the specified temperature and vacuum degree is higher than the specified value, high valve is opened, bypass valve is closed and front valve is opened. At this time, the vacuum chamber is vacuumized to meet the requirements of the process before heat treatment.

 

After the heat treatment process is completed, the vacuum chamber is filled with high-purity nitrogen by the heat exchanger for forced cooling to complete the whole process.

 

As for the price, there is a big gap. According to the size of the effective area you need and the different materials, the configuration is different. There will be a lot of difference.

 

working process

 

Vacuum brazing furnace is to clean and decontaminate the parts of the workpiece to be welded with flux, lay the solder (powder, granular, flake) and put another part (welding surface is also coated with flux). Fix the two parts in the furnace and heat it up to the temperature of solder melting to complete the welding. It uses the furnace temperature to raise the temperature of the workpiece, and melts the solder whose melting temperature is lower than the workpiece, so that the workpiece can be welded.

 

In this process, heating should be as slow as possible to keep the internal and external temperature of the product to be brazed consistent, otherwise the brazing quality will be directly affected. In the industrial production, preheating and holding temperature, energy storage temperature and heat preservation, brazing temperature, heat preservation and power cut cooling are the effective technological processes which can not only achieve the above purpose but also improve the production efficiency. The vacuum brazing temperature and holding time are the key factors affecting the quality of brazing.