SU893203A1 - Dewar flask and method of sealing it - Google Patents

Description

(5) METHOD OF SEALING THE DEWAR'S VESSEL AND DIARA VESSEL

I

The invention relates to instrumentation and is intended for the manufacture of Dewar vessels and thermostats, providing, at low power consumption, a high degree of accuracy in controlling the temperature of electronic devices.

The closest to the proposed technical essence and the achieved result is a method of sealing the Dewar vessel by heating, evacuating and closing the vessel with solder followed by cooling 1.

 the disadvantages of the known method of sealing the Dyuar vessel are; complex technological process and low reliability of vacuum preservation in the vacuum chamber, due to the presence of an extended weld seam between the body and the bottom of the vessel, the lack of fixation of the bottom in the body and the need to accurately withstand the softening of the bottom of the bottom, because the temperature is not high enough , and a higher temperature leads to the melting of the solder and getting it into the vacuum chamber of the vessel and, consequently, to a seal failure.

The purpose of the invention is to increase the reliability of sealing the vessel.

ten

This goal is achieved by the method of sealing a Dewar vessel by heating, evacuating and closing the vessel with solder, followed by cooling.

15, the vessel is sealed with a plug, the solder is made in the form of a frame on which the plug is installed, and heating is conducted to the melting point of the corners of the frame with

20 and then to the melting temperature of the rods of the frame with exposure.

Claims (2)

Known Dewar vessel containing the outer shell and the cap G2. The disadvantage of the known vessel is the low quality of the product. The purpose of the invention is to improve the quality of the vessel. The goal is achieved by the fact that in the Dioar vessel containing the outer shell with a hole, the inner shell and the cap, the needle is made with teeth that enter the hole of the outer shell, and the plug and outer sheath are sealed by a vacuum-tight seam. Figure 1 shows the Dewar vessel ground and installed for sealing vessels; figure 2 - frame and cap installed in the vessel Dew macaw before sealing; in FIG. 3 the construction of the plug; on fig.i section aa on fig.Z. The sealing of the Dewar vessel is carried out as follows. The Dewar vessel consisting of the outer shell 1 (for example, titanium grade VT1-0} and the inner shell 2 (for example, titanium grade VT1-0) is placed on screen 3 on table k under the cap St on which oDbt inductor 6 with magnetic A gasket 8 is placed between the glass bell 5 and the pipe 7 7. A frame 9 made of hard refractory solder (for example PSR 72) is mounted on the outer shell of the vessel. The frame is made with angles 10 and rods 11. the teeth of the plug 12 are fixed in the frame 9 and in the hole of the outer shell, while the corners of the frame 9 rest on the outer shell of the vessel and the rods of the frame 9 hold the plug 12 above the recess 13 in the outer shell. The plug is made with a cylindrical small surface Ti with a cylindrical middle surface 15 and a cylindrical large surface 16 with teeth 17 and grooves 18. With the frame and plug installed, additional channels are formed, Going through the corners of the frame 9 and the grooves of the plug 12 into the vacuum chamber 19, draw air through the nozzle 7 and create a vacuum under the hood 5 (for example, 5-10 mm Hg) and freely remove gases from the vacuum chamber 19 of the vessel. The number of additional channels and their sizes are quite large, so the residual pressure under the cap 5 is equal to the residual pressure in the chamber 19 of the vessel. Include inductor b with magnetic flux heat up the screen 3 (for example, from nickel NP-2). The radiant heat flux from the screen 3 simultaneously heats the outer shell 1 and the inner shell 2, the frame 9 and the plug 12 (for example, up to 650 ° C). Additional cycles are made {temperature is reduced (for example, three times lower before and again higher), with ZGO1L additional vessel degassing occurs. The temperatures of the shells .1 and 2, the frame 9 and the plug 12 (for example, up to) are increased and the corners 10 of the frame 9 are melted. Under the force of gravity of the plug 12, the rods 11, the frame 9 and the plug 12 fall into the grooves 13 of the outer shell and the solder The corners 10 of the frame 9 flow into the undercut 13. Withstand the temperature and melt the rods 11 of the frame 9. Under the action of the surface tension forces of the liquid soldering corners of the frame 9 and the force of gravity of the plug 12 solder of the molten rods 11 of the frame spread evenly over the surface of the point 13 in opposite direction forming the vessel not pop and wherein the vacuum chamber of the vessel. Lower the temperature to cool. melted ("} frame. The proposed method allows for a long time to maintain a vacuum of 5-10 mm Hg in the vacuum chamber of the Dewar vessel with an initial pumping vacuum of mm Hg and reduces the sealing process to 1 hour. Formula of invention 1 The method of sealing the Dewar vessel by heating, evacuating and closing the vessel with solder, followed by cooling, is that, in order to improve the reliability of sealing the vessel, the vessel is sealed with a plug, the solder is made in the form of a frame on which it is installed the cap, and the heating is carried out up to the temperature of the plots of corners of the frame with upper support, and then to the melting point of the rods of the frame with exposure. 2. A Dewar vessel containing an outer shell with a hole, an inner shell, and a cap is distinguished by $ 8932034 u and with the fact that, with the aim of better-Sources of Information, neither the quality of the vessel, the plug made into account during the examination yen with teeth entering hole1. UK patent outer shell, with plug and If 1i22702, cl. A 7 j A1702, 1976. outer shell spas vacuum-2 .. USSR author's certificate tight suture. .If 97236, cl. From 03 to 23/16,.