RU178435U1 - A device for assembling cylindrical parts from aluminum alloys for soldering - Google Patents

Abstract

The invention relates to technological equipment and can be used for soldering assemblies of aluminum alloy assemblies, which include cylindrical parts, for example, fittings of aircraft air systems. The device contains a base designed to accommodate the parts to be soldered and a clamp for compressing and fixing parts in position during the soldering process. The device is equipped with a centering mandrel, as well as threaded rods mounted on the base, the clamp is made in the form of a plate with holes, ties are passed through the holes, clamping nuts are screwed onto the threaded ends of which are screwed from above the plate, the centering mandrel is made in the form of a cylinder with a through axial centering hole and has the ability to center on one of the cylindrical parts, and in its centering hole through a spacer made in the form of a sleeve of ceramic material, has the ability Settings second cylindrical part. 1 ill.

Description

The utility model relates to technological equipment and can be used for soldering assemblies of assemblies made of aluminum alloys, which include cylindrical parts, for example, fittings of air systems of aircraft.

A device is known for assembling ceramic-metal assemblies for soldering, containing a hollow body, in which there are elements for installing parts of the soldered product, which allow alignment of cylindrical workpieces before soldering and provide preloading of parts during soldering (see RF patent for utility model No. 137222, cl. B23K 1/00, 2014).

The disadvantage of this device is the ability to solder only hollow cylindrical parts, which imposes a limitation on the range of soldered products.

A device is known for assembling a package of parts for soldering, containing a base with racks on which a clamping mechanism is installed in the form of pressure beams with screw clamps for fixing parts installed on the basis of the soldered parts (see AS USSR No. 1383946, class B21D 9 / 00.1996) - the closest analogue.

The disadvantage of this device is the lack of accuracy of the relative installation of the parts to be soldered due to the lack of elements of their relative centering, as well as the relatively high probability of their displacement from a given position in the process of fixing with screw clamps.

The technical result of this utility model is to improve the quality of brazing of cylindrical parts made of aluminum alloys by ensuring their relative centering and tight contact with each other through solder during assembly, as well as by maintaining the specified position of the parts during the brazing process and eliminating their jamming in the device.

The specified technical result is ensured by the fact that in the device for assembling cylindrical parts from aluminum alloys for soldering, containing a base designed to accommodate the parts to be soldered and a clamp for compressing and fixing the parts in a predetermined position during the soldering process, the new device is that equipped with a centering mandrel, as well as threaded rods mounted on the base, the clamp is made in the form of a plate with holes, couplers are passed through the holes, on the threaded ends Clamping nuts are screwed on top of the plate, the centering mandrel is made in the form of a cylinder with a through axial centering hole and can be centered on one of the cylindrical parts, and in its centering hole through a spacer made in the form of a sleeve of ceramic material, the second cylindrical detail.

It is known from the prior art that when connecting aluminum parts, diffusion brazing through a copper coating or foil is traditionally used. The formation of the compound is carried out due to the fact that when heated to solder, diffusion interaction of the base metal with a copper coating or foil occurs with the formation of a liquid phase, which acts as a solder. In this regard, one of the main problems in carrying out such a soldering process is the need to ensure tight contact at the junction.

In the absence of tight contact between the brazed parts, there is no diffusion interaction of the foil with the base metal, or, when using the coating, the liquid phase is insufficient to completely fill the gap. Therefore, to ensure the passage of the soldering process, it is necessary to use equipment, which, as a rule, is made of stainless steel.

In the manufacture of cylindrical samples, for tight preloaded parts, a cylindrical mandrel made of stainless steel should be used as a tooling element. In the process of heating by soldering, due to the large values of the coefficient of linear thermal expansion of the brazed material and the tool, the aluminum part is compressed in the steel mandrel, which makes it difficult to disassemble the tool after soldering.

To eliminate this phenomenon, a sleeve of ceramic material was used, which is placed between the aluminum part and the steel mandrel. The ceramic sleeve has a significantly lower coefficient of linear thermal expansion and high values of compressive strength. In this case, the sleeve should be made of a material that, at soldering temperatures, does not enter into chemical interaction with the components of the base metal of the parts and the mandrel.

The essence of the utility model is illustrated by graphic materials, which show a device for assembling cylindrical parts from aluminum alloys for soldering, axial section.

To describe the design of the device, its elements are indicated by the following positions:

1 - plate;

2 - threaded rods (four);

3 - item to be soldered;

4 - spacer in the form of a sleeve of ceramic material;

5 - centering mandrel made of steel;

6 - item to be soldered;

7 - base.

A device for assembling cylindrical parts from aluminum alloys for soldering contains a base 7, the holes of which (not shown) are vertically threaded studs 2. A clamping element made in the form of a plate 1 is mounted on the threaded studs 2 with holes, and coupling nuts are screwed onto the threaded ends of the couplers (not indicated by positions) located on top of the clamping element 1. The device also includes a centering mandrel 5 made of steel, made in the form of a cylinder with an axial through centering hole, which has the ability to install a spacer 4, made in the form of a sleeve of ceramic material.

The claimed device operates as follows. To assemble the brazed assembly, one brazed cylindrical part 6 is mounted on the base 7. A second brazed cylindrical part 3 is inserted into its axial hole with a gap, with a coating or a tacked solder foil (not shown) applied to the contact surface. The centering of the cylindrical part 3 relative to the cylindrical part 6 is carried out by a mandrel 5, which is installed on the centering girdle (not indicated by the position - see Fig.) Of the part 6. A sleeve 4 is installed in the centering hole of the part 6, and a second part 3 is installed in it, which during installation, it is centered relative to part 6. Tight contact of the connected surfaces of parts 3 and 6 is ensured by compressing them by means of a plate 1, which is carried out by coupling nuts.

Example.

Five samples were made of AMgb alloy, representing a fitting with a base for connecting the air line of the aircraft. On the inner surface of the samples (soldering place), a layer of copper of the grade MO 20–30 µm thick was galvanically applied.

Assembly was carried out in the proposed device. The steel mandrel was made of 12X18H10T. The ceramic sleeve was made of VK94 ceramic based on aluminum oxide, because This ceramic does not enter into chemical interaction with the alloying components of the alloy AMgb and steel 12X18H10T. The clamping device was made of molybdenum.

For soldering, the device with the assembled product was placed in a two-bell vacuum oven SGV-2.4-2 / 15. Soldering was carried out in vacuum at a temperature of 530-540 ° C under vacuum of at least 10 ^-3 Pa for 1.5-2 minutes. The brazed product was cooled together with the furnace.

After soldering, the samples were subjected to visual inspection, of which three samples were subjected to metallographic examination of soldered joints and two samples were tested for leaks using the “aquarium” method with an overpressure of 6 atm. As a result, the formation of high-quality soldered joints was established, without pores and loosening in all five soldered samples. Leak tests showed no leaks.

Thus, the use of the proposed device allowed for accurate centering of the parts before soldering and their compression without relative displacement during heating. The use of ceramic spacers - bushings made it possible to simplify the process of disassembling the device after soldering and to exclude the appearance of defects associated with the separation of the mandrel and the product.

Claims (1)

A device for assembling cylindrical parts of aluminum alloys for soldering, containing a base designed to accommodate the parts to be soldered, and a clamp for compressing and fixing the parts in a predetermined position during the soldering process, characterized in that it is equipped with a centering mandrel and threaded mounted on the base with studs, while the clamp is made in the form of a plate with holes, ties are passed through the holes, clamping nuts are screwed onto the threaded ends of which are screwed on top of the plate, moreover the centering mandrel is made in the form of a cylinder with a through axial centering hole and has the ability to center along one of the cylindrical parts, and a spacer in the form of a sleeve of ceramic material with the possibility of installing a second cylindrical part in it is installed in its centering hole.

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