DD146014A1 - METHOD AND DEVICE FOR LOOSENING PLATED PIPE ENDS - Google Patents

Abstract

The invention is particularly intended for the removal of tube-rolled, tube-type, exchangers. While the aim of the invent. The object is to provide a method and an apparatus whereby the removal of the rolled tube ends from relatively thick tubesheets can be carried out without difficulty. According to the invention, the tube ends are wound on their inner surface in a spiral or helical manner a depth sufficient to form a desired rice line, then first a short piece of each outer end is removed from the wall with simultaneous short passing of the desired rice line, pulled out and secured to a mandrel, bar or the like; finally by turning the mandrel or the like while passing along the desired Reiszlinie d. Loesen the tube strip is made from the bore wall and the peeled pipe strip is wound onto the mandrel or the like.

Description

WP B 23 D / 215 55 984/27

Method and device for releasing rolled pipe ends

Scope of the invention

The invention relates to a method for releasing the tubesplate-rolled ends of the tubes of, in particular, heat exchangers from the bore walls and a device for carrying out the method,

Chara kteristik the known t ^ echniscjiej jjösurigen

For example, due to vibrations occur on tubes of heat exchangers damage. Defective pipes must be pulled out of the tube plates and replaced by intact tubes.

Extracting damaged, rolled into the tube plates tubes prepared for tube plates with large wall thickness, eg «, with wall thicknesses of 100 ram and larger, difficulties, because on the one hand commercial tube extractors for removing the tubes from relatively thin tubesheets are not suitable, and there On the other hand, drilling out the rolled-in pipe ends would involve a high risk, because a slight bleeding of the drill would render the tube sheets unusable. "

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Object of the invention

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The aim of the invention is to provide a universally applicable method for releasing rolled-pipe ends and a necessary economic device with high utility value properties.

Explanation of the essence of the invention .

The invention is based on the object to provide a method of the type mentioned, with the removal of the rolled pipe ends from relatively thick tube plates can be done easily «, -

This object is erflndungsgemäß solved in that the pipe ends are cut on its inner surface in a spiral or helical in a sufficient depth to form a desired tear line depth, that then first a short piece of each outer end of the wall with simultaneous short rupture of the target tear line detached, pulled outward and od on a mandrel, rod, etc., is attached, and that finally od by turning the mandrel. Like. _O while simultaneously tearing along the desired tear line loosening of the tube strip from the bore wall and the detached pipe strip the thorn oed

A further development of the invention consists in that the 'device' for carrying out the method comprises a cutting tool with a spindle provided with cutting teeth and a long guide pin, a tool for releasing the short pipe start piece having a rotatable mandrel with clamping device

The invention will be described below with reference to an exemplary embodiment

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explained in more detail. In the accompanying drawing show:

1 shows a cutting tool in plan view,

Figure 2 is a section along the line II-II in Pigur 1 and

Figure 3 shows a rotatable mandrel with clamping device, in longitudinal section. <

A cutting tool 1 is. in Torrn of a Gev / indeschneider mit.Zchnzähne. 2 and a long guide pin 3 formed at the tip of the threaded spindle. Due to the long guide pin 3 an oblique attachment of the threaded spindle is avoided. The height h of the cutting teeth 2 is smaller by a predetermined amount than the wall thickness of the pipe to be removed in the region of the tube plates. The height of the incisors , 2 is chosen so large that the incision jiefQÖ.er _y spiral is so large that the incision line serves as a target tear line »In general, one will choose a pristine from the section tube wall thickness of a few tenths of a millimeter. On the out of the pipe end outwardly guided shaft of the cutting tool 1, an axially fixable ring 7 is arranged. The ring 7 is adjusted according to the thickness of the tube plate, so that the tube (pipe end) is scored to the correct length.

The starting piece of the cut pipe end is, for. B * by means of a chisel, detached from the bore wall and pulled out approximately outward from the bore, wherein the target tear line in this area tears simultaneously. This narrow initial strip is then clamped onto a rotatable mandrel 4, rod or the like by means of a locking screw 6 arranged in a ring 5 pushed over the mandrel 4 and clamped on the mandrel 4.

By turning the mandrel 4 about its longitudinal axis, the tear-off line is then loosened in the form of a narrow strip of material while simultaneously being torn at the suction line

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the bore wall as well as .in winding the detached, narrow tube strip on the mandrel 4 ·

If the two tube ends in the area of the tube plates peeled strip-shaped from the bore wall, then you can easily pull out the damaged tube completely and replace.

The inventive method is particularly advantageous for relatively thick Rolirplatten applicable. In principle. but it is also applicable to thin tube plates.

The main pipes to be replaced are defective heating and cooling pipes. of pressurized heaters or coolers.

Claims (2)

IT B 23 D / 215 §.ft -5- 55 984 27 Anspruch [en] A method for releasing the tube sheet-rolled ends of the tubes of, in particular, heat exchangers from the bore walls, characterized in that the tube ends are spiral-shaped on their inner surface   be cut helically in a depth sufficient to form a desired tear line that then first a short piece of each outer end detached from the wall with simultaneous short rupture of the target tear line, pulled outward and od eiiiem a mandrel, rod od. Like. Attached is, and that od finally by turning the mandrel. Like., At the same time! Tearing along the nominal tear line da.s loosening of the tube strip from the bore wall takes place and the detached tube strip on the mandrel. Like. Is wound up, 2. Apparatus for carrying out the method according to item 1, characterized in that it comprises a cutting tool (1) with a cutting teeth (2) and a long guide pin (3) provided spindle, a tool for. Release of the short tube start piece and a rotatable mandrel (4) with clamping device (5, 6). To this 1 sells drawings