FI81669C - SPIRALRIBBSROER. - Google Patents

Description

81 669 1 Splraallripaputki Spiralribbsrör 5

The innovation relates to a helical rib tube having a tubular element on which the ribs having a substantially flat rectangular cross-section are helically assembled, and in which the contact of the end edges of the ribs with the jacket surface of the tubular element supporting them is reinforced by welding.

For heating and cooling purposes, widened helical tubes have been designed, equipped with these helically wound ribs-15a, which provide their environment with a wide contact surface providing heat dissipation, and which can be used as a heat exchanger, heat exchanger, heat exchanger, evaporator .

In simple applications of splinter rib tubes, the ribs are made of a flat material having a rectangular or trapezoidal profile which is in fixed contact on the sheath of the tube element, thus transmitting heat insulation. In practice, however, it has been found that even when the ribs are subjected to prestressing, the actual contact results in only a partially narrowly defined surface area and is associated with undesirably high temperature gradients. Therefore, it is known that steps have been taken willingly to further improve heat transfer. Thus, for example, a material with an L-profile is used for the ribs, the short branch of the profile lying on the surface of the tube element so that the surface area of the transition area increases. In principle, however, this does not change the fact that only narrowly defined areas remain in direct contact from time to time. A dovetail profile was also used for the ribs in the support area, and the edges of the profile were rolled into the tubular element, thus significantly hampering and thus tilting the fabrication also not resulting in the desired trouble-free heat transfer between the ribs and the tubular element.

2 81 669 1 It is still known to join the ribs to the pipe element when assembling by the high frequency flux welding method. Here, relatively high high-frequency powers are required to produce a welding operation, and certain lights are also caused here by the import of high-frequency energy, 5 this must be brought locally into the respective welding area ., the pre-welded rib area continuously produces an electric side current to the instantaneous welding area. As a disadvantage, it has thus been shown that the weld seam thus obtained does not penetrate continuously, but that porous or pocket-shaped welded areas have formed and are included in the numerous hit-10 fairy tale areas. In this case, not only does the actually achieved heat transfer deteriorate compared to the optimally achievable pores or pockets formed between the tube element and the end edge of the rib above it, which causes undesired starting points of possible corrosion, so that the service life of the spiral tube thus welded is embarrassingly reduced.

The object of the invention is to provide a spray beam tube whose ribs are flawlessly, stably and with a large surface area connected to the tube element 20, so that not only the desired easy heat transfer is achieved, but also a mechanically stable and highly loadable beam tube with low corrosion sensitivity is formed.

This object is solved in that in the species-specific spiral flute tube 25 the ribs are connected on the other side of the ribs of the tube element by a weld seam at a small height part, which joins the ribs to the tube element without pores along their entire width. A shielding gas seal joining the ribs and the pipe element has been found to be good for this purpose.

The features of the novelty will be explained in connection with the description of the application example together with the drawing showing it.

The figure shows a truncated and partially cut tubular element 1, on which a through-threaded rib 2 is biased in a helical manner. Still during the twisting, the base parts of the ribs 2 just assembled on the pipe element 1 have been welded at their still free ends on the pipe element side with the jacket surface of the pipe element 1. By creating a ring seam

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3 81 669 1 the shielding gas welding method thus transfers material from the respective electrode to the shielding gas welding seam 3, which contributes to the complete filling and non-porous joint of the fitting both in the ribs 2 and in the pipe element 1. area · but, on the other hand, deviates somewhat higher. In this way, it is achieved that the pipe element itself enters the weld seam, but on the other hand the weld seam extends only to the area close to the pipe element. For the ribs, these are practically attached to the weld in its entire thickness. Thus, the corresponding electrode orientation in the weld Second welding is achieved through the ribs 15 so that they are connected to the pipe element 1 over the entire width of the weld seam 3. at the moment when the seal is completely molten, which completely excludes the entry of pockets, slotted holes, etc., which could act as a source of corrosion, thus achieving the desired goal. making a direct connection to a pipe element under which there is no risk of corrosion.

As in the known high-frequency drawing welding, there is a continuous welding in which the respective welding plate proceeds at a rotational speed.

25 However, no high-frequency electrodes or the like are required here, and the welding support is unambiguously determined by the welding electrodes used. But thus also here, as in the known high-frequency resistance welding, for example, the rotation speed must be adapted to the welding power.

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In the manufacture, it may be expedient not to conduct the shielding gas used, for example CO 2, not only to the welding side and thus directly to the front of the mounted rib, but possibly also to the rear of this rib by means of an additional supply line.

In each of these cases, the desired goal is achieved, by achieving a more secure joint with excellent thermal conductivity and thus 35 4 81 669 1 surely eliminates temperature interruptions in the joint area, which also increases both mechanical stability and especially chemical strength, avoiding virtually complete onset of corrosion.

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Claims (2)

5 81 669 A helical rib tube, comprising a tubular element (1) on which ribs 5 (2) having a substantially flat rectangular cross-section are helically assembled, and in which the contact of the end edges of the ribs (2) with the jacket surface of the tubular element supporting them is reinforced by welding, on the other side of the ribs (2) for a small part of the height of the ribs, a shielding gas seal (3) is lowered, which connects the ribs along their entire width without pores to the 10 pipe elements (1). 1 Claims A method of manufacturing a splinter rib tube according to claim 1, wherein the rib (2) having a substantially flat rectangular cross-section is helically assembled on the tubular element (1), the end edges of the ribs (2) being reinforced with the jacket surface of the tubular element (1) characterized in that the end edges of the ribs (2) and the shielding gas seal (3) connecting the jacket surface of the tube element (1) are formed by a welding electrode accompanying the weld to the weld (20) and directed from the free end of the tube element (1) ) to a small area formed between the shell line and the side of the rib (2) so that the resulting arc extends slightly above the small area comprising a portion of the height of the rib (2). 25 30 35 6 81669