DE3309416C2 - Tube support grid for tube bundle heat exchangers - Google Patents

Abstract

Pipe support grid for tube bundle heat exchangers, steam generators, etc., which consists of an outer lattice frame and rods attached to it, which form square pipe holding fields in a square or rhombus shape. The bars are divided into at least two bar grids (13, 14) which are axially spaced from one another and have square or rhombus-shaped tube holding fields and are formed from toothed sheet metal strips that are identical to one another. The points of intersection of one bar grid (13) are offset from the points of intersection of the other bar grid (14) so that a pipe support grid is formed from offset bar grids and is suitable for pipes of different sizes.

Description

3

the can. However, this is only possible if the individual pipes are located

Jacket is produced if it does not yet contain the center t is the center-to-center distance of two pipes in the x-direction Tube bundle is located device indicated, b is the thickness of the rods 16,17,19 and

From the condition that the Blindberohrvsngsverfah- 20. a is the center-to-center distance between two adjacent ones is to be used, the bar grid 13 and the mounting of the pipes would initially follow for 5 barter bars that these are the individual with Ax and Ay are the displacements in x and in

nen pipe only a very small possibility of movement in the y-direction indicated, whereby for Δχ and Ay the one in the pace leaves when it is introduced into the system. The equations given apply, means that the pipe in the lattice is as far as possible from all. From the figure it can be seen that instead of the

four sides is closely led. There may be known mesh tubes 21 larger tubes which can meet this requirement without therefore having to produce other rod grids 13 or 13, but then they inevitably have the disadvantage of having to be produced. With larger pipes is that when flowing through the medium in the operating ER- merely reduces the offset, in the limiting case Δχ considerable pressure losses may occur, which in turn be of sides and Ay zero. The theoretical borderline case for small pipes not accepted by the operator of the heat exchanger would be given if Jx = Mit , with. this arrangement form the two bar grids 13 and

Finally, a further requirement in practice is pipe holding fields that instead of one pipe 21 have four pipes to consider. When dimensioning heat exchangers with a smaller diameter, The inside diameter of the pipe u "d of the ab- In the embodiment shown in the figure

the tubes played a role in relation to one another and so far 20 with rhombus-shaped tube holding fields applies to Δχ and when designing a heat exchanger, the procedure Ay has been that, depending on the boundary conditions, the optimal one

Inner pipe diameter and the number of pipes or Ax = (t— 1.155a) Ay = -ß (t— 1 JiSa)

whose spacing has been determined. Mostly there was a simple geometric relationship between 25 For square pipe holding fields in an inclined position applies the pipe diameter, the distance and the thickness of the

Bars of the lattice, in other words that corresponded to Ax = Ay - ] / 2 (t-a)

Pipe holding field in its clear inner dimension essentially corresponds to the pipe outer diameter - even if the traps, the extensions of the rods in the x or rods of the individual grids lay axially one behind the other. 30 y-direction and the pipe holding fields are square. This meant that after the pipe inner diameter had been determined, the distance between the rods was fixed, and accordingly, for this chosen arrangement, Ax = Ay = (t-a)

matching grids are made, i.e. used

Rods had to have cutouts at a distance from each other. 35 1 sheet of drawings can be provided and put together.

The invention is based on the object of a Rohrhalterungs ^ itter of the type mentioned so that it does not have the disadvantages mentioned z. B. in With regard to vibration resistance, manufacturing effort and pressure losses, the grille being realized in this way should be that it can be used for pipes with different diameters.

This is achieved by a pipe support grid according to the patent claim.

With the help of the pipe support grid according to the invention, pre-punched bars can be used for the grid, whereby adjacent bar grids are arranged relative to one another in such a way that their intersection points are offset from one another. The size of the offset Ax and Ay can be derived from the equations mentioned, with explicit equations being given in the description of the figures for some frequently used grid shapes.

The invention is explained below with reference to the drawing, for example. The only figure shows a partial cross-sectional view of a pipe support grid made of two bar grids.

In the figure, the front bar grating is denoted by 13, it consists of rods 16 and 17 placed one inside the other, with the individual rods having recesses (not shown) have, so that a mutual reception of the rods is possible

Behind the bar grid 13 there is a bar grid 14, which is formed from corresponding bars 19 and 20 is. The bar grids 13 and 14 have an axial distance from one another, which in the limit case can be zero.

Within the rhombus-shaped pipe holding fields,

Claims (1)

1 2 of the grid of the support struts is a pipe on one or Claim: even in two places of the relatively large support struts guided. Pipe support grid for tube bundle heat exchange - From the spacing grid explained above Scher, which consists of an outer lattice frame and then another spacing lattice is developed on what There is attached rods, the pipe holding fields in the (DE-AS 22 63 056). In this generic Form a square or rhombus shape, but the supporting struts or the grating are marked grids characterized by the combination of following the support struts and dropped instead Features: Grooves or slots are formed in the lattice frame ίο been so that the bars of one bar field at the a) The bars (16, 17, 19, 20) are firmly branched in at least one side of the grid frame in these grooves Axially spaced apart can be welded and accordingly the rods Bar grids with a square or rhobus shape of the other bar field on the opposite Sei-pipe holding fields divided, the rods te of the lattice frame are welded accordingly (16,17,19,20) can consist of teeth that are identical to one another. In this embodiment, each tube is on th sheet metal strips formed and each one diametrically opposite points of rods ge-Stabgittcr (13 or 14) forming rods (IS, 17 holds or 19, 20) into one another with the help of the serrations are, punching grid known (DE-OS 28 40 146), which b) the points of intersection of one rod grid (13) a> bears a great similarity to the one in the first place to the intersection points of the other distancing grids, but they are Bar grid (14) arranged offset, support struts not provided with grooves or slots. c) for the lateral offset <Wder bar grids (13, but instead designed with through holes 14) the equation det applies to include the individual bars. 25 It is a pipe support grid for tube bundle heat 6X - c (t — g ■ a) exchanger known (GB-PS 12 23 045), in which the Bars are designed as sheet metal plates and two in and for the offset δY perpendicular to this, the axial spacing from one another applies to rod grids with the equation forming square pipe holding fields. The panels are 30 provided with serrations and can thus be combined OY - f (t-h · a), be stuck that each pipe from a pipe holding field or -fach is surrounded where cg, t and Λ geomstric constants It is also a pipe support grid for tubes that take into account the rhombus angle, T bundle heat exchanger known (GB-PS 15 84 242), with the center-to-center distance of adjacent tubes and c 35 in which the bar grids are formed as stamped parts , the sum of the outer pipe diameter plus so that between the pipe holding fields there is webs thickness of a rod that are very wide and because of the punching process therefore a poor occupancy of the heat exchangers conditional available space with pipes. 40 In the literature, the individual advantages and disadvantages of known spacing grids have been listed, es The invention relates to a Rohrhalterungsgit- is particularly concerned with vibration security ter according to the preamble of the claim. of the tube bundle in operation and the manufacturing It is a spacing grid for the tube bundle heat wall of the grid. The individual grids like lower exchangers known (CH-PS 4 89 745), which from an external 45 have differences in this regard, in the Ren lattice frame and rods attached to it, dimensioning the known spacing grid for the tube holding fields in square or rhombus form bil- tube bundle heat exchangers are however the pressure verden, wherein the rods as two to each other an axial holding when flowing through the fluid through the Be-spacing having and each in a? »· Radial plane rich of the grid in connection with the bracket or horizontal bar fields as well as guidance of the individual tubes in the respective bar field 50 are not taken into account worparallel to one another, but with one another. different rod direction of the two rod fields are arranged and where the rod directions of the two tube heat exchangers should be blind tubed. To-bar fields intersect at such an angle, the next is that of several cylindrical parts zudaß through the rods of both rod fields, square pipe- 55 jacket welded together with the pipe plate be formed from a rhombus shape, all weld seams processed and tested the. For the vibration-proof mounting of the rods are non-destructive tests. Then they are inside Additional support struts with larger dimensions than the shell are provided for the spacing grids on the Rods are provided, which are inserted crosswise into one another. Now, one after the other are pushed and a diamond field with a relatively large 60 the individual tubes in the place intended for them Form a rhombic surface. The support struts are introduced with Schiit- This means that the individual guides zen or grooves are provided so that the rods can be accommodated in the tubes so that they are precisely aligned with one another men. Overall, this spacing grid consists of the relatively long but thin tubes inserted two bar fields, whereby the bars of a field can be joined together without damaging the pipe are parallel and the rods of the two rod fields occur in μ ren. The requirement for blind pipes bc / .ug are arranged on top of each other at an angle. see from the newer examination regulations, because in Each individual pipe is diametrically opposed in pairs - it is required that the individual weld seams overlying areas of bars are defined, reworked in the area of the jacket after production