SU1279152A1 - Apparatus for sealing a pipe by resistance butt welding - Google Patents

Abstract

The invention relates to sparking technology and can be used in butt welding machines for hermetic sealing with the help of pipe plugs, mainly shells of tpels made of split zirconium. Invention povpilet quality of a pair of

Description

by improving the alignment of the location during its execution of the plug relative to the pipe being welded, and thereby increasing the uniformity of distribution of the welding current around the perimeter of the parts being joined, it saves the material of the plugs by welding the plugs without shanks to the pipe. The device (U) provides welding to the support with the exception of the increase in residual stresses in the welded joint. Y consists of two parts, each of which has its own clamping mechanism for the welded workpieces, which together form a sealed welding mic12.

rockamer The welding microcamera is associated with means for creating a vacuum and supplying neutral gas. U contains a welding pressure drive and a welding current source. U is designed in such a way that the plug 6 is clamped in a mechanism mounted in one part of U, due to the floating mounting of the holder electrode of the plug 12 and the centering sleeve 13 automatically when parts of the machine are aligned, is centered with a clamp-clamp 9 of another part, the mechanism of which clamps another workpiece, thus eliminating all gaps. 1 hp f-ly, 4 ill.

one

The invention relates to welding technology, and more specifically to welding machines for sealing by resistance butt welding with help of plugs of fuel claddings, mainly of zirconium alloys, nuclear power reactors.

The aim of the invention is to improve the quality of welding by improving the alignment of the location in the process of its implementation plugs relative to the welded pipe and thereby increasing the uniformity of the distribution of welding current around the perimeter of the jointed parts, saving material plugs, achievable with, even the possibility of welding to the pipe plug without a shank, as well as ensuring the possibility of welding on the anvil with the exception of the increase in the welded joint of the residual tensile stresses.

Figure 1 shows the proposed device, a longitudinal section; in figure 2 and fig.Z - its variants; figure 4 - welded joint, longitudinal section.

The device consists of two guides 3 and 4, coaxially mounted on the frame 1 through the insulation 2, into which the current lead-slider 5 is placed, respectively, of the plug 6 (in FIG.

a variant of the stub without a shank is shown) and the current lead-slider 7 of the tube 8. In the latter there is a collet 9, in the bore of which three feathers are fixed

three sectors 10 detachable annular stop-current lead welded pipe 8. Sectors 10 secured together with them in a closed state sector 11 annular separable catcher electrode holder 12 of the plug 6. Floating electrode holder 12 of the plug 6 is made in the form of a flange sleeve with internal diameter

the fit, which exceeds the diameter of the shank of the plug 6, on the working one, designed to fit the shank of the plug, part of which is mounted on the running fit, the centering

elec / rod holder 12 plugs 6,

the flange also has a sleeve 13 with an outer sleeve 15 insulated with the help of a ring-insulator 14, coupled by a running fit along the load

the diameter with the inner diameter of the sectors 11 of the annular detachable catcher of this sleeve, attached to the sectors 10 of the detachable annular abutment joint with them, of the welded pipe 8.

Claims (1)

A compression spring 16 is placed between the flanges of the electrode holder 12 of the plug 6 and its centering sleeve 13, and the centering sleeve 13 is equipped with a forward travel hub, which is made in the form of a tubular nut 17 on the end of the coupling nut 17 of the body elongation, the body elongated and on the flange centering the electrode holder 12 eagluki 6 sleeve 13 are filled with cutouts of the bayonet lock. In this case, on the nut nut 17 of the slide 5 of the plug 6, the ring stop is made with an internal diameter smaller than the internal diameter of the thread, 0.05-0.1 mm in height, exceeding the thickness of the flange of the holder electrode 12 of the plug 6. Last from the working side the end face at a length equal to the height of the working part of the plug has a cylindrical groove with a diameter of 0.1-0.3 mm smaller than the diameter of the electrode holder 12. Fit for the working part of the plug 6 a part of the centering sleeve 13 at a length equal to the height of the working part plugs insulated with isolation Ring 18 from the rest of this bushing. The guide 3 of the slider 5 of the plug is provided with an annular groove in which the rubber sealing ring 19 is inserted and the insulating sleeve 20 is pressed in, which is the catch of the end part of the pipe slider 7. In addition, this guide is provided with a seal 21, which, together with the seals of the collet 9 and the welded pipe 8 on the slide 7 (not shown), seals the welding microchamber. Channels connecting the welding microcamera to the means of creating a negative pressure and a neutral gas supply, the welding pressure drive and the source of welding current are also not shown in the figures. The proposed device works as follows. With the slider 7 pushed to the right and the collet 9 unfolded into the holding electrode 12 and the extreme right position pushed aside by the compression spring 16, the centering sleeve 13 (until its flange stops in the annular protrusion of the flare nut 17), which with its shank / if the latter is present, it is placed in the bore of the electrode holder 12, and the working part is placed in the bore of the centering sleeve 13, insulated to prevent shunting of the welding current from its part (in the absence of the shank, the plug is placed in the bore ntriruyuschey sleeve 13). At the same time, the electrode holder 12 with the centering sleeve 13 and the lower arm can move together in a plane perpendicular to the axis of the slide 5, since the ring stop on the cap nut 17 in the tightened position of the last preBbmiaeT is the thickness of the flange electrode holder 12 by 0.05-0 , 1 mm, and set in the lowest position. Next, through the central hole in the slider 7 and the collet 9, the pipe 8 to be welded is fed into the plug 6 and clamped (by its sectors 10 of the split ring-stop current supply pipe by means of the collet 9 until the sectors 10 are completely closed (the latter are bored in a closed state in one installation jointly with sectors 11 of the ring catcher, with sectors 10 being bored by a diameter of 0.02-0.03 mm smaller than the minimum tolerance of the outer diameter of the pipe being welded, and sectors 11 by a diameter larger than the diameter of the centering sleeve 13c impaled and on its end by an isolator ring 1A and an outer casing 15 for the tolerance value for the running fit.) After the slider 7 is fed to the extreme left position, it CBOJtM ends up in the insulating sleeve 20 and seals the welding microcamera by compressing the rubber ring 19 with its end face. In this case, the front part of the centering sleeve 13 is located in the bore of the divorced (with an unseated collet 9) sectors 11 of the ring split splitter of this sleeve. When clamping the collet 9 of the welded pipe 8, the compression of the sectors 11 simultaneously exposes the centering sleeve 13, the holding electrode 12, and hence the plug 6 to the coaxially welded pipe, regardless of the manufacturing tolerances of other parts of the device, their wear, replacement, accuracy from cooking and etc. This ensures uniform distribution of the welding current around the perimeter of the parts to be welded, and, consequently, the uniformity of their heating, which ensures high quality welding. Thereafter, a boiling force is applied to the slider 5 and a pulse of cooking current is applied. In this case, the c-, plrka can be performed on the support, that is. with limited movement of the slider 5 at the final stage of precipitation. Structurally, such a restriction can be performed, for example, in the form of a nut placed on the outer diameter of the slider, with which it is possible to adjust the amount of progress of the latter by changing the distance between this nut and the fixed guide 3 of the slider 5. In this case the force shrinkage. KN of the heated metal of the seam, without causing tension in the seam, pull the shank of eaglux 6 out of sleeve 13 by a small amount. When rigidly clamping the shank of the plug, welding to the stop leads to an increase in the seam of residual, post-weld stresses Nij stretching. Welding to the support is convenient in that it ensures the integrity of the geometry of welded joints with a high degree of accuracy. In addition, it allows the simplest method, for example, by setting a limit switch on the support, to control the amount of press-fit of the plug into the pipe and thereby (indirectly) the quality of welded joints. After welding, the collet 9 is unclamped and the welded product along its axis is removed from the welding device. Thus, the sleeve 13 is held in its position by an annular collar of a cap nut 17. Fig. 2 shows the second variant of the welding device, which can be used for welding plugs with shanks. In this embodiment, in order to simplify the design of the device, the centering bushing is integrated with the plug holder electrode (see Fig.1) in one piece of the centering electrode holder 2 This allows the crawler nut 17 to crawl a 5 without an extension and to relieve the compression spring 16. FIG. 3 shows a variant of the device with a centralizer 23 of the electric holder 22, ensuring that the latter is held in a central position with respect to the central position of the slider 5 at all stages of operation of the device (including when the slider is retracted to the right position and 7 decompressed collet 9) In this embodiment, the centralizer 23 is made in the Vzdezda ciddrichnogo rod with a cone with a corner at the apex of 60-120 °, the diameter of which exceeds the diameter of the central bore of the electrode holder 22. The centralizer 23 of the vertical cone is inserted into the bore of the electrode holder 22 and using a spring 24 cone pressed to the electrode holder 22. The spring 24 is free, and the centralizer 23 on the landing fit placed in the central hole made in Ttsovoy part of the slide 5 plugs. Such a design of the device reliably fixes the initial axial position of the electrode holder 22 and reduces the wear of the surfaces of the yoke 15 and the sectors 11 of the annular detachable catcher when the slide 7 is brought to the slide 5. The experimental design of the proposed device has shown that misalignment on the welded product plugs and pipes. This is also explained by the fact that, in addition to a good initial alignment of the parts to be welded, the absence of a rigid clamping device for the shank of the plug does not interfere with the self-installation of the latter during the welding process, due to the fact that with this type of welding the cylindrical working part of the plug when pressed into the end of the pipe deforms and turns into a truncated cone. The structure of the welded joint obtained on the proposed device is shown in its longitudinal section in FIG. 4. The use of the invention makes it possible to improve the quality of welding, reliability of sealing of a fuel rod, simplify monitoring, reduce the production of equipment, reduce the cost of materials in one of the most important operations - the operation of sealing. Claim 1. Device for sealing contact butt welding of a pipe, mainly a fuel cladding, contains coaxially mounted on the frame through the insulator two guides, in one of the K (5th mode, with the possibility of axial movement of the current lead-crawl) plug with a floating centering sleeve and an electric holder clamped onto: a slider knob nut 7 one, and in the other a current lead-half-pipe of a pipe with a collet, in a cylindrical point of the feathers of which the sectors of an annular stop-current squared are fixed yes pipes, the slider guide stub is made with a Schmylindrical groove, in which a rubber o-ring and insulating sleeve catching the end part of the pipe slider are mounted, vacuum seals of the parts forming the welding microcamera, channels connecting the welding microcamera with means of creating a vacuum and supplying a neutral gas, a welding pressure drive, and a welding power source, characterized in that, in order to improve welding quality by improving the alignment of the plugs, both ends of the pipe to be welded and thereby increase the uniformity of distribution of the welding current along the perimeter of the connection; parts, ensuring that the plugs without a shank can be welded to the pipe with savings due to this material of the plugs, as well as providing the possibility of welding on the stop with the exception of the increase in the welded joint residual stresses of the stub in the form of a sleeve with a flange, the floating tririding sleeve is made with a flange mounted on the working end of the electrode-D6rzh. The body of the plug on the running fit is equipped with an outer yoke electrically isolated from it. for the working part of the blind, the part of the centering sleeve is electrically isolated from the rest of it; the sectors are provided in this connection of the landing fit; the electrode-holder of the plug is provided with a compression spring mounted on it with the possibility of interaction between its flange and flange the cement of the centering sleeve, the sliding nut of the slide is made with a tubular extension with two inward-facing annular stops of the axial movement of the holder electrode and the centering sleeve, while the circular stop from the side of the nut of the coupling nut is made with an inner diameter smaller than the internal diameter of the thread and the height exceeding the thickness of the flange of the holder electrode of the plug, at the working end of which there is a trickle groove with a diameter smaller than the diameter of the holder electrode. 2 Device according to claim 1, characterized in that, in order to reduce the wear of the outer ring of the centering electrode holder, it is provided with a centralizer of the initial position of the holder electrode of the plug made in the form of a cylindrical spring-loaded rod with a cone whose angle is 60-120 °, and the diameter of which exceeds the diameter of the central bore, made in the holder electrode, while the rod with a cone along the running fit is mounted in the central hole, made in the end part of the slider of the plug. tS 20JJ S 8 7 3 S I 12 W 6) 42 Thebes. 2