JP2011515648A - Low vibration tube bundle support device - Google Patents

Abstract

Tube bundles (10) for shell and tube type heat exchangers have a support system, which allows simple manufacture and provides a fixed support for the tube (12), vibration and vibration related problems Reduce. The tube bundle is composed of tubes supported by spaced cages (22), with the cage (22) having support rods (26), which provide sufficient clearance with adjacent tubes. Sized and configured in alternating positions and orientations, so that four widely spaced cage sets form a complete support network. In order to ensure fixed support to avoid vibrations, a set of support stakes (30) is inserted adjacent to (or between the cages) to bias the tube relative to the support rods of the cage. . This simplifies manufacturing but maintains a fixed support system.
[Selection] Figure 1

Description

  The present invention relates to heat exchangers, condensers and tubes or devices in devices such as, for example, nuclear reactors, electric heaters, or any assembly of parallel cylinders with fluid flow through tubes or other elements. It relates to a tube bundle device such as a similar fluid handling device having an assembly of rod-like elements.

  Tube bundle equipment, such as shell and tube heat exchangers, and similar items of fluid handling devices, such as flow dampers and rectifiers, utilize tubes organized in bundles to communicate fluid through the equipment. In such tube bundles, there is typically a fluid flow through the inside of the tube and a fluid flow over the outside of the tube. The configuration of the tubes in the bundle is determined by the tube plate on which the tubes are installed. One common configuration for tubes is rectangular or square with tubes arranged as aligned rows with tube lanes (straight path between tubes) between each pair or row aligned orthogonal to each other. It is a configuration. In this configuration, each tube is adjacent to eight other tubes except at the periphery of the tube bundle and directly faces the corresponding tube across a tube lane that separates the column from two adjacent columns. In a triangular tube configuration, the tubes in every other row so that each tube is adjacent to six other tubes (two adjacent tubes in the same row and four tubes in two adjacent rows). Are aligned with each other.

  In order to reduce capital costs by reducing equipment size or to increase productivity factors, it is often desirable to increase the throughput of existing switches. A common limiting factor associated with assessing rate increases in exchangers is the possibility of pipe flow-induced vibration damage. The fluid flow pattern around the tube may result in flow-induced vibrations with organized or random vibration properties within the tube bundle.

  In the case of devices such as heat exchangers where heat transfer occurs between the tube and the surrounding fluid, vibrations can occur due to changes in the temperature and density of the fluid as it flows around the tube. May increase. If these oscillations reach some critical amplitude, bundle breakage may occur. Tube vibration problems can be exacerbated when the heat exchange device is replaced with a tube made of a material different from the original tube, for example, when a relatively rigid material is replaced with a lighter tube. Also, when equipment is subject to more stringent operating requirements, for example, heat exchangers that were previously satisfactory, while other existing equipment is up to date, will flow under new conditions. Flow-induced vibrations may occur when subjected to induced vibrations. Under certain conditions where heat exchangers are still in the flow, but no heat transfer takes place, and others with rods or aggregates of rod-like elements in the flow, with or without heat transfer In some tube bundle devices, vibrations can even occur.

  Vibration damage is a costly situation for most situations in an operating plant. Although heat exchangers can have thousands of tubes, a single tube failure can cause the process unit to shut down, resulting in considerable economic loss. Therefore, reducing or eliminating vibration is a highly desirable goal. Another advantage of minimizing the possibility of vibration is that the power consumption of the gas compressor can be greatly reduced and energy costs are greatly saved, so the axial shell in the circuit with the gas compressor Is to allow the use of side flow.

  Several different instrument designs have been improved to address the tube vibration problem. One example is a rod baffle design. A rod baffle heat exchanger is a shell and tube type heat exchanger that utilizes a rod baffle to support the tube and to secure the tube against vibration. Further, rod baffles can be used to reduce the non-uniform distribution of shell side flow and produce a more uniform shell side flow. The term “rod baffle” refers to a tubular ring disposed about every 15 cm along the length of the tube bundle, with the ends of a plurality of support rods connected internally to form a cage-like tube support structure. To do.

  However, rod baffle exchangers tend to be about 20-40% more expensive than conventional shell and tube exchangers. Furthermore, a situation has arisen in which this type of tube bundle device fails due to flow-induced vibration. An important problem with rod baffles is that it is difficult to load tubes between rods. In order to provide a fixed support and minimize vibration, the rod spacing is very close to the tube diameter. In some configurations, the rod diameter is approximately the same as the size of the lane between the tubes. This necessitates very careful passage of the tube through the cage, greatly increasing the difficulty and time involved in installation. The rod baffle heat exchanger is described in Patent Literature 1, Patent Literature 2, Patent Literature 3, and Patent Literature 4, for example.

  As described in U.S. Patent No. 6,047,086, certain applications of rod baffle designs, such as surface condenser and power plant applications, can benefit from longitudinal flow with minimal shell side pressure loss. it can. The reduction in shell side pressure loss may be achieved by increasing the rod baffle spacing, thereby reducing the number of rod baffles, or measured from the tube pitch dimension, i.e., the center of the tube. This may be achieved by reducing the number of tubes by increasing the distance between two adjacent tube rows. Increasing the baffle spacing is not usually an attractive option because increasing the baffle spacing increases the likelihood of flow-induced tube vibrations. Reducing the number of tubes by increasing the tube pitch dimension reduces the shell side pressure loss with respect to the longitudinal flow between the rod baffles, but requires a large support rod diameter, and the rod baffle pressure loss Which may offset all the reduction in the shell-side pressure loss of the longitudinal flow obtained by reducing the number of tubes. This also makes the exchanger more expensive by increasing the shell diameter for a specified number of tubes. The rod baffle design described in U.S. Patent No. 6,057,836 is an attempt to address the pressure drop problem of rod baffle configurations. Another example of a design intended to avoid a significant increase in longitudinal flow shell side pressure loss is described in US Pat.

  Alternative designs are the “Eggcrate” and “Square One” designs. However, they can be more expensive than the rod baffle design and do not eliminate tube chattering that can cause tube failure. Chattering is the movement of the tube against the tube support mechanism due to the gap between the support mechanism and the tube outer diameter. The gap is required to allow the tube to be inserted through the egg crate or square one support mechanism when the bundle is constructed. Therefore, the rod baffle design is a more promising starting point from an economic and operational standpoint.

  In addition to good equipment design, other measures may be taken to reduce tube vibration. Tube support devices, or tube stakes commonly known as these support devices (referred to herein), are used in tube bundles to control flow-induced vibrations and to prevent excessive movement of tubes. May be installed. Several tube support mechanisms or tube stakes have been proposed and are commercially available. For example, Patent Literature 5 granted to Williams, Patent Literature 6 granted to Hahn, Patent Literature 7 granted to Hahn, and Patent Literature 8 granted to Hahn are inserted into the tube bundle to reduce vibration. Various types of tube stakes or tube support mechanisms that can be described are described. Improved tube stakes are shown in US Pat. Nos. 5,098,086 and 5,037, both granted to Wanni et al., The contents of which are hereby incorporated by reference.

  Tube bundle devices have been developed that are believed to be more effective, reliable, easier to manufacture, and less expensive than conventional heat exchangers of the rod baffle type. The contents of which are incorporated herein by reference. In that device, a tube support cage, similar to a rod baffle, is spaced further along the length of the tube, for example, every 50-200 cm, and in most cases about 60-150 cm apart. Placed, thereby making the manufacture of such tube bundles much easier and cheaper than conventional rod baffle devices where the rod baffle support mechanism is typically placed about 15 cm or less apart become. In contrast to the cages being provided in every other tube lane in the rod baffle design, the tubes are supported by rods or flat bars in each tube lane at the cage location. The tube bundle is reinforced by inserting tube stakes between tube support cages, preferably at the midpoint of the tube range between the cages. While this system is effective, it is desirable to provide an alternative design that can be manufactured with a simple manufacturing process while still ensuring vibration relaxation.

US Pat. No. 4,342,360 US Pat. No. 5,388,638 US Pat. No. 5,553,665 US Pat. No. 5,642,778 US Pat. No. 4,648,442 US Pat. No. 4,919,199 US Pat. No. 5,213,155 US Pat. No. 6,401,803 US Pat. No. 7,032,655 US Patent Application Publication No. 2005/0279487 US Patent No. 7,073,575 US Pat. No. 7,219,718

  Some aspects of the present invention are tubes that are arranged parallel to each other and define a tube bundle having a longitudinal axis, having x tube lanes separating adjacent rows and y tube lanes separating adjacent columns. And a tube bundle device comprising tubes arranged in a matrix. The tube bundle device is a first tube support cage with a baffle frame, wherein a plurality of parallel tube support members, each extending in a first orientation in every other x tube lane, have a longitudinal axis. A first tube support cage secured to the baffle frame in a substantially vertical plane, and a second tube support cage comprising a baffle frame, wherein the first tube support cage is the first in every other y tube lane. A second tube having a plurality of parallel tube support members each extending in a second orientation at an angle relative to the orientation of the tube and secured to the baffle frame in a plane substantially perpendicular to the longitudinal axis A third tube support cage with a support cage and a baffle frame, each extending in a first orientation within every other x tube lane offset from the first tube support cage by one lane. Multiple parallel tube support members are A third tube support cage secured to the baffle frame in a plane substantially perpendicular to the axis and a fourth tube support cage comprising the baffle frame, one lane from the second tube support cage A plurality of parallel tube support members, each extending in a second orientation within every other y tube lane that is offset by, are secured to the baffle frame in a plane substantially perpendicular to the longitudinal axis. And a fourth tube support cage. At least one set of tube support stakes adjacent to one of the tube support cages, substantially parallel to at least some of the tube support members of adjacent tube support cages and offset to alternate lanes thereof, And spaced apart and inserted into the tube bundle. The first, second, third, and fourth tube support cages form a set that collectively defines a grid of tube support members disposed in each x tube lane and each y tube lane. The tube support member has a thickness between 80 and 98% of the width of the x tube lane or the y tube lane, thereby defining a free space between each tube and the adjacent tube support member. A tube support stake biases the tube relative to the adjacent tube support member.

  A set of tube support stakes may be disposed adjacent to each tube support cage. A set of tube support stakes can be disposed between adjacent tube support cages in the set.

  Also, some aspects of the present invention are tubes that are parallel to each other and define a tube bundle having a longitudinal axis, the x tube lane separating adjacent rows and the y tube lane separating adjacent columns. And a tube bundle device including tubes arranged in a matrix. The device is a first tube support cage with a baffle frame, wherein a plurality of parallel tube support members each extending in a first orientation within every other x tube lane are substantially in the longitudinal axis. A first tube support cage fixed to the baffle frame in a generally vertical plane and substantially parallel to and offset from at least some of the tube support members to the first tube support cage And a first set of tube support stakes that are adjacent and spaced from the first tube support cage and inserted into the tube bundle. The second tube support cage includes a baffle frame and includes a plurality of parallel tube support members each extending in a second orientation at an angle relative to the first orientation in every other y tube lane. A second set of tube support stakes secured to the baffle frame in a plane substantially perpendicular to the longitudinal axis, wherein the second set of tube support stakes is substantially parallel to and offset from at least some of the tube support members; It is inserted into the tube bundle adjacent to and spaced from the second tube support cage. A plurality of parallel tubes each having a baffle frame and extending in a first orientation in every other x tube lane offset from the first tube support cage by one lane; A support member is secured to the baffle frame in a plane substantially perpendicular to the longitudinal axis, and a third set of tube support stakes is substantially parallel to and from at least some of the tube support members. A stagger is inserted into the tube bundle adjacent to and spaced from the third tube support cage. A plurality of parallel tubes each having a baffle frame and extending in a second orientation in every other y tube lane that is offset by one lane from the second tube support cage; A support member is secured to the baffle frame in a plane substantially perpendicular to the longitudinal axis, and a fourth set of tube support stakes is substantially parallel to and from at least some of the tube support members. Shifted and inserted into the tube bundle adjacent to and spaced from the fourth tube support cage. The first, second, third, and fourth tube support cages form a set that collectively defines a grid of tube support members disposed in each x tube lane and each y tube lane. Each tube support cage is separated by a distance of at least 300 mm as measured along the longitudinal axis. The tube support stake biases the tube relative to the adjacent tube support member, thereby reinforcing the tube to withstand the possibility of flow induced vibration.

  Additional tube support stakes may be provided adjacent the tube bundle inlets and outlets to provide additional support for the tubes in these areas. The tube support stake can have a plurality of spaced apart depressions and corrugations.

  Furthermore, the present invention is a heat exchanger having a bundle of tubes for transporting a fluid for heat exchange, the tubes being arranged parallel to each other and defining a bundle of tubes having a longitudinal axis, wherein the tubes are arranged in adjacent rows. Intended for heat exchangers having tubes arranged in a matrix with spaced x tube lanes and y tube lanes separating adjacent rows. The tube bundle includes a set of four tube support cages. Each tube support cage includes a baffle frame, and a plurality of parallel tube support bars are secured to the baffle frame in a plane substantially perpendicular to the longitudinal axis. A set of four tube support cages are axially spaced along the longitudinal axis, and the tube support bars of the two tube support cages extend in a first orientation in alternating x tube lanes, and others Tube support bars of the two tube support cages extend in a second orientation at an angle relative to the first orientation in alternating y tube lanes. At least one set of tube support stakes is adjacent to at least one of the tube support cages substantially parallel to and offset from at least some of the tube support members of adjacent tube support cages in the braided configuration. And spaced apart and inserted into the tube bundle. The tube support stake is formed with a seat for supporting the tube. A set of four tube support cages jointly define a grid of tube support bars disposed within each x tube lane and each y tube lane, each tube support cage being a separate tube support cage in the set. Separated by a distance of at least 300 mm as measured along the longitudinal axis. The tube support bar has a thickness of up to 98% of the width of the x tube lane or the y tube lane, thereby defining a free space between each tube and the adjacent tube support bar. A tube support stake supports the tube at the seat and biases the tube relative to the adjacent tube support bar.

  These and other aspects of the invention will be apparent upon consideration of the following detailed description, particularly when taken in conjunction with the drawings.

FIG. 2 is a simplified schematic diagram of a tube bundle having tubes supported by the tube support cage and tube stake according to the present invention showing enlarged details of the tube support cage and tube stake. It is an enlarged view of the pipe stake used with the pipe bundle of FIG. FIG. 3 is an enlarged view of another pipe stake used with the pipe bundle of FIG. 1. It is a side perspective view of the conventional rod baffle bundle. FIG. 2 is a simplified schematic diagram of a variation of the tube bundle of FIG. 1 having an additional tube stake at the end of the tube bundle.

  Similar elements in the drawings bear the same reference numerals.

  In the present description and claims, the terms "vertical" and "horizontal" are used in a relative sense with respect to the orientation of the tube support cage elements and stakes, i.e. with respect to each other and with respect to the axis of the device. Represents the relative orientation of an element or stake. Thus, the expression “vertical” orientation means that the orientation is orthogonal to the designated “horizontal” orientation, and does not suggest that the orientation is truly vertical or truly horizontal. This is especially true when the axis of the heat exchanger itself is vertical or horizontal and therefore all support cages and stakes are truly horizontal. That is, the expressions “vertical” and “horizontal” with respect to tube support cage elements and stake orientation are such that the longitudinal axis of the tube bundle device is itself truly horizontal and the specified orientations are relative to each other; It is made under the assumption that it is not true. For example, in a heat exchanger with a truly horizontal longitudinal axis, the tube support cage elements may be at a 45 ° angle to the true horizontal / vertical, but still “vertical” and “horizontal” with respect to each other. It is. In heat exchangers with a vertical longitudinal axis, all elements of all tube support cages are truly horizontal, but nevertheless their orientation with respect to each other about the longitudinal axis is orthogonal Are considered “vertical” and “horizontal”.

  The present invention will be described with reference to a shell and tube type heat exchanger. In this heat exchanger, a bundle of heat exchanger tubes is secured between the tube sheets inside the shell, and liquid is passed through and around the tubes for heat exchange. This type of tube bundle can be used in a heat exchanger as described, or in any other type of ordered configuration of condensers, nuclear fuel rod devices, or parallel tubes through which fluid flows. For convenience, for simplicity, the present invention will be described with reference to a device as a heat exchanger, although other tube (or rod) bundle devices may be constructed in accordance with the principles of the present invention. The tube bundle is mounted in a conventional manner in a surrounding shell, for example having two fixed tube sheets if the exchanger operates with only a small temperature, or more generally There is one stationary tube sheet and one floating tube sheet, or the U-shaped tube bundle has only one (stationary) tube sheet.

  FIG. 4 shows a conventional heat exchange tube bundle 100 using a rod baffle support system. As is known, the bundle 100 is composed of a plurality of elongated heat exchanger tubes 102 that are arranged in parallel and secured by tube sheets 104 at each end. Tubes 102 are separated from each other by tube lanes. A plurality of rod baffles 106 are disposed about every 150 mm along the length of the heat exchanger tube 102. Each rod baffle 106 is formed as an annular ring 108 that supports the end of a support rod 110 that extends across the ring 108. As shown, support rods 110 extend across the bundle in the lane between tubes 102. With this configuration, vibrations induced by the flow of liquid through the bundle can be reduced. In this system, the size tolerance of each support rod 110 must be carefully designed. In order to support the tube 102 in close proximity, only a small gap is provided to load the tube 102 in place through the baffle 106, which makes loading difficult and increases manufacturing costs. However, if the rods 110 are made smaller to provide easier tube loading, the bundle will not be able to avoid vibrational damage, particularly at the shell inlet and outlet.

  FIG. 1 shows a tube bundle 10 designed to address these issues. As described below, the tube bundle 10 is designed to accommodate greater throughput and to be smaller than existing exchangers. These conditions may increase the speed in the tube bundle and tend to generate vibration.

  The tube bundle 10 comprises a number of parallel tubes 12 in a rectangular arrangement, i.e. a row 14 of tubes 12 and a column 15 of tubes 12 extend in two directions, with an x tube lane and a y tube lane 16 each being a tube. Defined between row 14 and tube column 15. As can be seen from the drawings, only a few rows, columns, and lanes are labeled for the sake of brevity, but these reference signs are intended to represent each row, column, and lane, respectively. Should be understood. Tube 12 is connected to tube sheets 18, 20 at each end of the tube bundle in a conventional manner. These tube sheets 18, 20 are installed in the shell of the exchanger. Of course, other arrangements of the tubes 12 within the bundle 10 are possible, including for example a triangular arrangement. Accordingly, the lane space 16 needs to be adjusted to fit the tube support member 26.

  The tube 12 is supported by a tube support cage 22 disposed at intervals along the length of the tube 12. The tube support cage 22 is of four different types, and these types are repeatedly arranged across the bundle and are designated A, B, C, and D in the drawing. Each tube support cage 22 is formed from a ring 24 or plate baffle with a central notch window. A plurality of tube support members or rods 26 extend across the central open region and are secured to the ring 24 at their ends. The cage 22 can be manufactured in advance so that it can be assembled more efficiently and cheaply.

  The rod 26 may be any shape, but is preferably in the form of a flat bar welded to the baffle. Of course, the rod 26 may be any shape, including a circular, rectangular, or square cross section, and is referred to herein as a “rod” for convenience and simplicity, regardless of their cross-sectional shape. The rod 26 may be welded directly to the side of the ring 24 (over the wall thickness of the ring 24) or, in more complex constructions, appropriately to fit the rod cross-section formed by the drill. Received within a recess or aperture in the shaped annular ring 24, the rod is secured within the recess or aperture by welding, brazing, or other securing means.

  The thickness of the rod 26 is preferably smaller than that of the tube lane 16. In order to provide sufficient clearance around the rod 26 to insert the tube 12, the rod thickness can be in the range of 98%, preferably 90% to 98% of the width of the lane. In the case of a rod 26 configured as a flat bar, this thickness means the width of the bar. For example, the rod 26 may be about 95% wide of the tube lane 16. In particular, if the tube lane, measured as the distance between two adjacent tubes, is 6.35 mm, the rod will be 6.0-6.2 mm thick. This allows the tube 12 to be easily inserted into a pre-manufactured cage 22, which makes bundle loading a fairly simple task. In large diameter bundles, the small rods may be deflected by the flow, so it is desirable to use a flat bar as the rod 26 so that it has greater elasticity and consequently greater axial strength. Sometimes. It is also envisaged to use several crossbars to reinforce the main bar. However, even if there is no support by the rod 26, the effect of the entire support system is not reduced. This is because, as explained below, additional support is provided by the tube stake inserted into the tube bundle.

  As mentioned above, there are four different configurations of the cage 22. Four types A, B, C, and D are shown in FIG. The different configurations relate to the orientation of the cage 22 when installed in the bundle 10. As used herein, the terms “horizontal” and “vertical” are used descriptively to indicate the relative positions of adjacent elements. Thus, it should be understood that the entire assembly can be rotated and thus reoriented without changing the relative orientation of the elements.

  As shown, the first type A has horizontally disposed rods 26 that start from the bottom of the ring 24 and are between every other horizontal row 14. Separated to be disposed within the tube lane 16. The second type B has vertically arranged rods 26 that start from the left of the ring 24 and in the y-tube lane 16 between every other vertical row 15. Are spaced apart from each other. The third type C has rods 26 arranged horizontally, which start from the top of the ring 24 in the x-tube lane 16 between every other horizontal row 14. Separated to be disposed. The fourth type D has rods 26 arranged vertically, which start in the right part of the ring 24 and in the y-tube lane 16 between every other vertical row 15. Are spaced apart from each other. Thus, each cage 22 has a rod 26 that is oriented in only one direction. This allows each set of four cages 22 of type A, B, C, D to provide a rod 26 in every lane 16 between each row 14 and each column 15 of tubes 12 to fully support the bundle. To do.

  Each tube support cage 22 is positioned at intervals along the length of the bundle 10. In this configuration, the spacing is wider than a conventional support cage, for example, at least 300 mm between the cages 22. The spacing can be 600 mm (for a 19.05 mm diameter tube) and 1200 mm (for a 25.4 mm diameter tube) between the cages 22. If desired, the distance between the support cage / stake can be increased in the central part of the exchanger. This is because the axial velocity at the central portion of the bundle 10 is parallel to the tube and is therefore less likely to cause vibrations. The cages 22 are secured together by tie bars or tie rods 112, for example as seen in FIG.

  By reducing the size of the rods 26, using less cages 22, and every other configuration of rods 26, loading of the tube 12 through the cages 22 can be easily accomplished. After the tube 12 is loaded, additional anti-vibration support is provided by insertion of the tube support stake 30 to reinforce the tube 12 arranged as a bundle.

  Referring to the top row of FIG. 1, four different configurations of anti-vibration (AV) tube support stake 30 are shown from left to right as AV-A, AV-B, AV-C, and AV-D. Yes. The tube support stakes 30 at each location are arranged in the same direction and in lanes between every other row or column. Configuration AV-A utilizes two tube support stakes 30, both of which are horizontally disposed and offset from two adjacent lanes 16 where rods 26 of adjacent cages 22 are positioned. Arranged in lanes 16 between the rows 14. This can be understood by comparing the configuration of the A cage 22 with the AV-A stake configuration in FIG.

  Similarly, configuration AV-A utilizes two tube support stakes 30 that are disposed vertically in lanes 16 between rows 15 and start from the left side of the bundle. Configuration AV-B utilizes two tube support stakes 30 that are disposed horizontally in lanes 16 between rows 14 and start from the top of the bundle. Configuration AV-D utilizes two tube support stakes 30 that are vertically disposed in lanes 16 between rows 15 and start from the right side of the bundle. Similar to cage 22, this configuration provides a tube support stake 30 in every x-tube lane 16 and y-tube lane 16, each set of four configurations between row 14 and column 15, respectively. Of course, if the bundle is made up of more tubes 12, more rods 26 and more tube support stakes 30 are used at each position. As long as rods 26 and corresponding tube support stakes 30 are disposed in alternating lanes 16, each row 14 and each column 15 is fully supported. All tube support stakes 30 may be joined at each position, for example by a circumferentially braided cable and / or clamp.

  As can be seen in FIG. 1, the positions of the cage 22 and the tube support stake 30 are also alternating. The type of each adjacent cage 22 and the configuration of the tube support stake 30 are similarly oriented. For example, cage type A has horizontally oriented rods 26 that are arranged in alternating lanes with horizontally oriented tube support stakes 30 of configuration AV-A. This is also true for each adjacent associated pair: B and AV-B, C and AV-C, D and AV-D.

  In a rectangular tube arrangement, every other vertical / horizontal arrangement of support rods 26 causes the tube support stakes 30 in each set to be parallel to one support rod 26 of an adjacent cage 22, so that the tube 12 is The support stake 30 holds firmly against the support rod 26 which is parallel to them. In a triangular tube arrangement, the orientation of the support stake 30 at a given location is parallel to one support rod 26 of an adjacent cage 22 and can hold the tube firmly against the rod 26 of that cage 22. preferable. Of course, in a triangular arrangement, the spacing between the tubes will be slightly wider and the alternating orientation of the cage and stake may be an angle that is not 90 degrees. Thus, the shape formed by the rods and stakes in each set may be a diamond rather than a square.

  The alternating configuration is advantageous in that it allows more free fluid flow through the bundle. The parallel alignment of the tube support stake 30 and the support rod 26 of the adjacent cage 22 and the offset configuration has the effect of urging any tube 12 against the support rod 26 or stake 30 and ultimately Give the bundle the rigidity it needs for good operation. Inserting the tube support stake 30 into the tube bundle pushes the tube 12 away from the surface of the support stake 30 and biases the tube 12 toward the rod 26. This effect is similar to a woven basket. In this way, the tube 12 is slightly displaced (up to 2 mm), providing tube support not only at the tube support stake position but also at the tube support cage position.

  Note that no support stake is provided at the longitudinal center of the bundle between the two sets of cages since the tube support stake 30 is not required in all areas between the cages 22. This is especially true near one or more central regions between the inlet and outlet nozzles. This is because the shell flow is mostly axial and has a very low tendency to cause vibrational damage. Depending on the particular bundle configuration and vibration analysis, the tube support stake 30 may be eliminated at other locations. The specific design will be application specific.

  One variation of the present invention is illustrated in FIG. In this variation, the tube bundle 50 includes additional tube support stakes 30 disposed in AV-A ′ and AV-AD ′ to provide additional bundle reinforcement of tubes at the inlet and outlet regions of the bundle, Ensure that all bundle tubes are well supported. If the tube bundle is U-curved (ie, the inlet and outlet regions are on the same side of the bundle), the additional tube support stake is only in one position (ie AV-A ′ or AV-AD ′). It is assumed that it should be provided.

  The tube support stake 30 has any configuration, provided that it is dimensioned to increase the tube separation upon insertion into the tube bundle to hold the tube tight against the cage support rod. Can do. Thus, for example, the pipe stakes described in Patent Document 5 granted to Williams, Patent Document 6 granted to Hahn, Patent Document 7 granted to Hahn, and Patent Document 8 granted to Hahn, the dimensions thereof are It can be used on condition that it is perfect for this purpose. However, the preferred tube stake type is that shown in U.S. Patent No. 5,677,096 to Wanni et al., And this patent is referred to for a description of these preferred tube stakes referred to as recessed tube support mechanisms. Another preferred form of tube stake that can be used as well is described in US Pat. No. 6,057,037, and is referred to this patent application for a description of these preferred tube stakes, referred to as saddle tube support mechanisms. Combinations of these types can also be used. Full details of these types of support mechanisms are disclosed in the above-mentioned patents and patent applications incorporated by reference herein, and also in US Pat. A configuration is disclosed.

  Referring to FIG. 2, a recessed tube support stake 40 is shown disposed in the lane between the tubes 12. The hollow tube support stake 40 is formed as a stake or strip 42 having an elongated body with a series of raised portions, corrugations, or hollows 44 spaced to form a seat for each adjacent tube 12. FIG. 3 shows a saddle tube support mechanism 50 formed as a stake 52 formed from two sheets 54 of rigid material, each sheet 54 having opposed raised areas having a rounded central cup 58. 56 or corrugated, a central cup 58 forms a seat for each adjacent tube 12. Of course, different configurations and methods of forming the seat are possible. These configurations allow for easy insertion and securely lock the tube in place. Also, the manufacture of those configurations is economical.

  In these types of tube support mechanisms or stakes, the corrugations facing the tube act to slightly deflect the tube to provide elastic support for the tube while simultaneously easily inserting the support stake into the bundle It can be so. Each tube support stake has a recess at its outer edge, which also slightly deflects the tube, but more securely locks against the outermost tube, during handling or operation. Minimize the possibility of undesirable displacement of the tube support stake. The present invention is not intended for use in connection with tube support mechanisms having indentations and / or corrugations. It is envisioned that other support devices could also be used inside the tube lane to press or bias the tube against the rod.

  If desired, bypass shrouds can be provided above and below the tube bundle 10 to prevent longitudinal diversion of the shell side fluid. These shrouds are known and are formed with a flat surface that abuts the outermost tube and a peripheral flange at each end. The flange is a circular chord with a diameter that matches the inner diameter of the exchanger shell, so that when the tube bundle is inserted into the shell, the flange fits closely inside the shell and the shell into the shroud region Prevents ingress of side fluid. The shroud can be formed with a standard length and shroud so that it extends over the tube in all areas except the inlet and outlet ends where flow to the shell inlet and outlet is required. Can be bolted (or otherwise fastened together) through a flange. The shroud is secured to the tube support cage, for example, by bolting the flange together with the tube support cage in between, so as to obtain adequate rigidity.

  In a triangular tube arrangement, a set of tube support cages and tube support stakes can be similarly arranged, in which case the alignment of the support rods in the cage at each successive axial position is a multiple of 60 °. Only so that it returns to the initial alignment at the fourth position (ie, the support rod is continuously aligned at 0 °, 60 °, 120 °, etc.) and the stake is similarly aligned. Inserted with a pattern. Assuming that the tube support stake is preferably inserted parallel to the support rod of the adjacent support cage, a typical insertion mode is that the relative angular position of the cage support rod and tube support stake is zero with respect to the first cage. It is indicated by angular displacements of °, 60 ° and 120 °. In a triangular tube arrangement, the spacing of the tubes 12 may be slightly wider than in conventional arrangements to accommodate the cage support rods.

  During assembly, the tube 12 is inserted through the cage 22 and inserted into one or both tube sheets 18,20. In the case of a tube bundle with a U-tube that is received in one tube sheet, the cage 22 is placed at the free end of the tube 12, and then the tube 12 is secured to only one tube sheet. In the case of a bundle having two tube sheets, the tube 12 is usually advanced through the cage 22 into one or both tube sheets, and then the tube sheet according to the exchanger design, for example by welding or using an expansion joint. Fixed to one or both.

  While the above description has described an arrangement in which the pitch and tube dimensions are constant, the assembly disclosed herein is configured to work for rows of tubes having varying pitches or varying tube dimensions. Those skilled in the art will appreciate that this can also be done. For example, the interval or curvature of the seat portion of the tube support mechanism can be easily corrected. Further, those skilled in the art will appreciate that various changes and modifications may be made to the configurations herein and that they are within the scope of the invention as defined in the appended claims.

Claims (23)

A tube bundle device,
Tubes arranged parallel to each other and defining a tube bundle having a longitudinal axis, arranged in rows and columns, with x tube lanes separating adjacent rows and y tube lanes separating adjacent columns tube;
A first tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. A first tube support cage that is in a plane and each extends in a first orientation into every other x tube lane;
A second tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. Second tube support cages that extend in every other y tube lane in a second orientation that is in a plane and each of the tube support members is in a second orientation that is at an angle to the first orientation;
A third tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. In the plane, each of the tube support members being shifted in the first orientation by one lane relative to the first tube support cage and extending into every other x tube lane. 3 tube support cages;
A fourth tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. In the plane, each of the tube support members being displaced in the second orientation by one lane relative to the second tube support cage and extending into every other y tube lane. 4 tube support cages; and at least one set of tube support stakes inserted into the tube bundle, adjacent to one of the tube support cages but spaced from it, adjacent to the tube support stake A tube support stake that is substantially parallel to and offset from at least some of the tube support members of the cage and is in every other lane;
The first, second, third and fourth tube support cages form a set which jointly defines a grid of tube support members disposed in each x tube lane and each y tube lane;
The tube support member has a thickness between 90 and 98% of the width of the x tube lane or the y tube lane, so that a free space is provided between each tube and the adjacent tube support member. Define
The tube bundle device, wherein the tube support stake biases the tube with respect to the adjacent tube support member.   The tube bundle device of claim 1, wherein each tube support cage is 95% of the width of the x tube lane or the y tube lane.   The tube bundle device of claim 1, wherein the tube support cages are spaced apart by a distance of at least 300 mm as measured along the longitudinal axis.   2. The tubes of claim 1, wherein the tubes have a diameter in the range of 12-22 mm, and the tube support cages are separated by a distance of 500-700 mm as measured along the longitudinal axis. Tube bundle device as described in.   5. A tube bundle device according to claim 4, wherein the tubes have a diameter of 19 mm and the tube support cages are separated by a distance of 600 mm.   The tube bundle device of claim 1, wherein the tubes have a diameter in the range of 23-40 mm, and the tube support cages are separated by a distance of 1100-1300 mm.   7. A tube bundle device according to claim 6, wherein the tubes have a diameter of 25.4 mm and the tube support cages are separated by a distance of 1200 mm.   2. The tube bundle device of claim 1, wherein there is a set of tube support stakes disposed adjacent to each tube support cage.   The tube bundle device of claim 1, wherein there is a set of tube support stakes disposed between adjacent tube support cages in the set. A tube bundle device,
Tubes arranged parallel to each other and defining a tube bundle having a longitudinal axis, arranged in rows and columns, with x tube lanes separating adjacent rows and y tube lanes separating adjacent columns tube;
A first tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. A first tube support cage that is in a plane and each extends in a first orientation into every other x tube lane;
A first set of tube support stakes inserted into the tube bundle, adjacent to the first tube support cage, but spaced therefrom, to at least some of the tube support members A first set of tube support stakes that are substantially parallel and offset therefrom;
A second tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. Second tube support cages that extend in every other y tube lane in a second orientation that is in a plane and each of the tube support members is in a second orientation that is at an angle to the first orientation;
A second set of tube support stakes inserted into the tube bundle, adjacent to the second tube support cage, but spaced therefrom, to at least some of the tube support members A second set of tube support stakes that are substantially parallel and offset therefrom;
A third tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. In the plane, each of the tube support members being shifted in the first orientation by one lane relative to the first tube support cage and extending into every other x tube lane. 3 tube support cages;
A third set of tube support stakes inserted into the tube bundle, adjacent to the third tube support cage, but spaced therefrom, to at least some of the tube support members; A third set of tube support stakes that are substantially parallel and offset therefrom;
A fourth tube support cage including a baffle frame, wherein a plurality of parallel tube support members are secured to the baffle frame, the tube support members being substantially perpendicular to the longitudinal axis. In the plane, each of the tube support members being displaced in the second orientation by one lane relative to the second tube support cage and extending into every other y tube lane. Four tube support cages; and a fourth set of tube support stakes inserted into the tube bundle, adjacent to the fourth tube support cage, but spaced therefrom, and the tube support member A fourth set of tube support stakes substantially parallel to and offset from at least some of the
The first, second, third and fourth tube support cages form a set which jointly defines a grid of tube support members disposed in each x tube lane and each y tube lane; The tube support cages are spaced apart by a distance of at least 300 mm as measured along the longitudinal axis;
The tube bundle device, wherein the tube support stake biases the tube with respect to the adjacent tube support member.   The tube support member has a thickness between 90 and 98% of the width of the x tube lane or the y tube lane, so that a free space is provided between each tube and the adjacent tube support member. 11. The tube bundle device of claim 10, wherein the tube bundle device is defined.   11. The tube bundle device of claim 10, wherein the tube support cages are separated by a distance of at least 600 mm as measured along the longitudinal axis.   The tube bundle device of claim 10, wherein the tube support cages are spaced apart by a distance of at least 1200 mm as measured along the longitudinal axis.   14. The tube support stake has a plurality of spaced apart projections, the projections forming a seat for the adjacent tube. Tube bundle device.   15. The tube bundle device of claim 14, wherein the spaced apart protrusion is one of a spaced indentation and a spaced corrugation.   14. A tube bundle device according to any of the preceding claims, wherein the tube support stake has a plurality of spaced saddles, each saddle forming a seat for an adjacent tube. .   Some of the tube support stakes have a plurality of spaced recesses, some of the tube support stakes have a plurality of spaced saddles, and the recesses and saddles are for the adjacent tubes. The tube bundle device according to claim 16, wherein the tube bundle device is formed.   14. A tube bundle device according to any of the preceding claims, wherein at least some of the tube support stakes have a combination of depressions and saddles that form seats for adjacent tubes.   The tube bundle device according to claim 1, wherein each of the tube support members is a flat bar.   20. A tube bundle device according to any preceding claim, wherein each baffle frame is formed from a plate having a central cutout window.   21. The tube bundle device according to claim 1, further comprising a shell and a tube sheet connected to the shell that supports the tube bundle.   The tube bundle has a first end forming an inlet region and a second end forming an outlet region, and the tube bundle device is on one of the first end and the second end 22. A tube bundle device according to any of claims 1 to 21, further comprising at least one additional tube support stake inserted into the tube bundle adjacent thereto. A heat exchanger having a bundle of tubes for transporting a fluid for heat exchange,
Tubes arranged parallel to each other and defining a tube bundle having a longitudinal axis, arranged in rows and columns, with x tube lanes separating adjacent rows and y tube lanes separating adjacent columns tube;
A set of four tube support cages, each including a baffle frame, with a plurality of parallel tube support bars secured to the baffle frame, the tube support bars substantially extending along the longitudinal axis In a vertical plane,
The four sets of tube support cages are axially spaced along the longitudinal axis, so that two of the tube support bars of the set of tube support cages every other one of the tube support cages. x tube lanes extending in a first orientation, and the other two tube support bars of the tube support cage set in every other y tube lane in the first orientation. A set of four tube support cages extending in a second orientation at an angle with respect to the tube bundle; and at least one set of tube support stakes inserted into the tube bundle, wherein one of the tube support cages Adjacent, but spaced from, substantially parallel to and offset from at least some of the tube support members of adjacent tube support cages having a braided configuration, Pipe support formed with a seat for supporting the pipe Including holding stakes,
The four sets of tube support cages jointly define a grid of tube support bars disposed within each x tube lane and each y tube lane, and each tube support cage is within the set. Spaced from the other tube support cage by a distance of at least 300 mm as measured along the longitudinal axis;
The tube support bar has a thickness of at most 98% of the width of the x tube lane or the y tube lane, thereby defining a free space between each tube and the adjacent tube support bar. And
The heat exchanger according to claim 1, wherein the tube support stake supports the tube by the seat portion and biases the tube with respect to the adjacent tube support bar.

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