Vacuum Brazing of Liquid-cooled Shell

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1. Background Technique

The dam shell is an important part of the active phased array radar antenna. A set of radar antennas often has a large number of dam shells. The cooling method adopts internal circulating liquid cooling. The liquid cooling form requires the tightness and liquid flow of the shell. Very high. The liquid-cooled shell is vacuum brazed from two identical blanks with water channel grooves to form a welding blank. Due to the small diameter of the inlet and outlet water channels, in addition to ensuring airtightness during welding, the inlet and outlet water channels must also be prevented from being blocked. The thickness of the welding sheet used in the existing liquid-cooled shell welding is 0.15mm, and the number of compacted blocks on the surface of the workpiece is at least 36. When the shell is welded, it is easy to cause the solder to flow into the flow channel and excessive solder overflow Block the inlet and outlet waterways, causing the product to be scrapped.

Therefore, it is necessary to provide a new type of liquid-cooled shell vacuum brazing method to solve the above-mentioned problems.

2. Steps

1). Soldering piece processing and pretreatment: cutting the soldering piece according to the cross-sectional shape of the welding part, and grinding, physically cleaning and drying the cut soldering piece.

2) Assembly of welding parts and welding pieces: evenly place a number of welding pieces between the two welding parts, and place them on the cleaned welding plate after assembly.

3) Place the pressure block: a single-piece pressure block is used to compact on the surface of the workpiece according to the position of the welding piece.

4) Cover stainless steel cover: cover the workpiece with a stainless steel cover, and place a certain amount of magnesium in the stainless steel cover.

5) Welding: Put the welding plate and several placed workpieces into the vacuum brazing furnace in batches for vacuum brazing. Set the furnace temperature to 620℃, and power off when the workpiece temperature reaches 591℃ , Cooled to 500℃ with the furnace, and forced to cool to room temperature with nitrogen.

6) Shell post-welding treatment and processing: Take out the workpiece, use the hardness to test the surface strength, test the flow channel tightness through the airtight pressure holding test, and then precisely process the subsequent through-holes and shape structure until the final product is obtained.

3. Technical Parameters

Model	Temperature Uniform Size	MAX. Temperature	Ultimate Pressure	Pressure Rising Rate	Temperature Uniformity	Loading Capacity
RVB-559L	500*500*900mm	850℃	4~8*10-4Pa	0.5Pa/h	±3℃	150Kg
RVB-669L	600*600*900mm	850℃	4~8*10-4Pa	0.5Pa/h	±3℃	200Kg
RVB-6612L	600*600*1200mm	850℃	4~8*10-4Pa	0.5Pa/h	±3℃	300Kg
RVB-107012L	1000*700*1200mm	850℃	4~8*10-4Pa	0.5Pa/h	±3℃	500Kg
RVB-7816L	700*800*1600mm	850℃	4~8*10-4Pa	0.5Pa/h	±3℃	800Kg
RVB-100714L	1000*700*1400mm	850℃	4~8*10-4Pa	0.5Pa/h	±3℃	1000Kg
RVB-111325L	1100*1300*2500mm	850℃	4~8*10-4Pa	0.5Pa/h	±3℃	2000Kg

Shanghai Geheng Vacuum Technology Co., Ltd. is a vacuum heat treatment furnace manufacturer with many years of experience in design, manufacturing and production. Mainly produce vacuum heat treatment furnace, vacuum sintering furnace, vacuum brazing furnace, New Energy And Environmental Protection Equipment and Vacuum Carbonization Furnace .Provide customized services, equipment work area can be based on customer output.