Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28G—CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
  • F28G1/00—Non-rotary, e.g. reciprocated, appliances
  • F28G1/12—Fluid-propelled scrapers, bullets, or like solid bodies
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
  • B08B9/02—Cleaning pipes or tubes or systems of pipes or tubes
  • B08B9/027—Cleaning the internal surfaces; Removal of blockages
  • B08B9/04—Cleaning the internal surfaces; Removal of blockages using cleaning devices introduced into and moved along the pipes
  • B08B9/053—Cleaning the internal surfaces; Removal of blockages using cleaning devices introduced into and moved along the pipes moved along the pipes by a fluid, e.g. by fluid pressure or by suction
  • B08B9/055—Cleaning the internal surfaces; Removal of blockages using cleaning devices introduced into and moved along the pipes moved along the pipes by a fluid, e.g. by fluid pressure or by suction the cleaning devices conforming to, or being conformable to, substantially the same cross-section of the pipes, e.g. pigs or moles
  • B08B9/0551—Control mechanisms therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
  • B08B9/02—Cleaning pipes or tubes or systems of pipes or tubes
  • B08B9/027—Cleaning the internal surfaces; Removal of blockages
  • B08B9/04—Cleaning the internal surfaces; Removal of blockages using cleaning devices introduced into and moved along the pipes
  • B08B9/053—Cleaning the internal surfaces; Removal of blockages using cleaning devices introduced into and moved along the pipes moved along the pipes by a fluid, e.g. by fluid pressure or by suction
  • B08B9/055—Cleaning the internal surfaces; Removal of blockages using cleaning devices introduced into and moved along the pipes moved along the pipes by a fluid, e.g. by fluid pressure or by suction the cleaning devices conforming to, or being conformable to, substantially the same cross-section of the pipes, e.g. pigs or moles
  • B08B9/0552—Spherically shaped pigs

Definitions

• the invention relates to a system for cleaning tubes of tube bundle heat exchangers, which have a plurality of tubes arranged parallel to one another between two chambers and are flowed through by a flow medium, in particular crude oil, at a temperature above 120 ° C., for cleaning the tubes
• a flow medium in particular crude oil
• tube bundle heat exchangers namely so-called crude oil heaters (COH)
• COH crude oil heaters
• the crude oil is heated in stages using several COH heat exchangers ⁇ connected in parallel and in series.
• the tubes of the heat exchanger are heated from the outside with process medium.
• the heat transfer to the tubes of the heat exchanger leads to deposits and incrustations from particles from the crude oil flow on the inside of the tube. These worsen the heat transfer with the result of less heating of the crude oil.
• the mechanical cleaning processes that are effective during the ongoing operation of the heat exchanger are subject to the very high operating temperatures, which are above 120 ° C and can easily reach ranges of around 400 ° C, as well as the chemical stress caused by use in an aggressive medium such as crude oil special requirements.
• cleaning elements permanently installed in the heat exchanger is based on the principle of fastening cleaning bodies such as helical spring elements or the like to a receiving device at the inlet of the heat exchanger, which are arranged loosely in the tubes and extend through the tubes.
• the cleaning elements consist of temperature and medium resistant materials.
• the receiving device enables axial movement of the cleaning elements in the tube. there are created by the shape and arrangement of the cleaning elements turbulence in the flow medium, which delay the formation of deposits.
• dirt particles or the like adhering to the inner wall of the pipe are removed by the movement of the cleaning element, so that deposit formation is substantially prevented.
• roller-shaped cleaning brushes are used, each of which runs back and forth between the inlet and the outlet of the tube to which they are assigned and can thereby clean a coating from the inner wall of the tube.
• a basket is arranged at the inlet and outlet of each tube. The basket at the outlet holds the brush when it has passed through the tube with the fluid. The brush is returned to the basket on the inlet side so that it is available for a new cleaning cycle through the pipe.
• WO 99/23 438 a system for cleaning the tube of single tube heat exchangers emerges as known, which are used primarily in petrochemical plants as end heaters.
• the tube of such a heat exchanger usually has a meandering course and can easily reach a length of 1000 m.
• a cleaning body referred to as "pig" passes through the single pipe under the pressure of the flow medium, the contact surface which is in engagement with the inner wall of the pipe under the action of a contact force cleaning deposits from the inner wall of the pipes which are carried out of the pipe with the flow medium.
• the cleaning body has a cylindrical hollow shape and its diameter is adapted to the diameter of the individual tube.
• the pressure required for pressing the contact surface of the tubular body against the inner wall of the tube is determined either by the pressure of the flow medium or by a support structure which is under radial tension and which, for. B. can be designed as a coil spring.
• the cleaning body is closed on one side so that the dynamic pressure can be used for the forward movement.
• the cleaning body is made of metal so that it is temperature-resistant and resistant to aggressive flow media such as crude oil.
• the length of the cleaning body is always considerably larger than the diameter of the individual tube.
• the cleaning body is constantly kept in circulation or collected, stored and, if necessary, reused in the individual pipe by means of apparatus arrangements.
• the cleaning body always cleans only one tube, namely the respective individual tube of the heat exchanger, which it may pass through several times.
• Cleaning body is always guided on all sides in the pipe through the inner wall of the pipe, and always in one and the same direction.
• the cleaning body can therefore not in the flowing flow medium with large flow cross sections, the z. B. can be found in the chambers of a tube bundle heat exchanger, transport freely.
• the cleaning body would rather sink in the flowing flow medium due to its high weight or high density and consequently z. B. sink in the chamber of a tube bundle heat exchanger on the inlet side in front of the tube sheet of the heat exchanger and only reach the lower edge of the tube sheet.
• a distribution of such cleaning bodies on the surface of the tube sheet of the heat exchanger is therefore excluded, and the cleaning body cannot align itself on the tube sheet for entry into a tube.
• the present invention seeks to provide a system for cleaning tubes of tube bundle heat exchangers for flow media, in particular crude oil with a temperature above 120 ° C, in which a cleaning of the inner wall of the heat exchanger tubes despite the A large number of tubes are carried out in tube bundle heat exchangers while the heat exchangers are in operation.
• the system is intended to meet the requirements set by a flow medium that has high temperatures and can be classified as chemically aggressive.
• a cleaning system of this type is characterized in that
• the cleaning body are designed such that they are temperature resistant (above 12 o ° C) and are resistant to aggressive flow media such as crude oil and - in the flowing flow medium, especially with large flow cross-sections such as in the chambers of the heat exchanger, are freely transported and sink or rise in the standing flow medium, and have an outer contact surface suitable for cleaning deposits from a pipe inner wall, under which Pressure of the flow medium pass through the tubes and are pressed with their contact surface under the action of a pressing force against the inner wall of the tube.
• temperature resistant above 12 o ° C
• aggressive flow media such as crude oil and - in the flowing flow medium, especially with large flow cross-sections such as in the chambers of the heat exchanger
• the system according to the invention allows the tubes of tube bundle heat exchangers to be cleaned while the heat exchanger is in operation and the other components of the system to which the heat exchanger is assigned.
• the cleaning bodies provided for this purpose are resistant to high temperatures and aggressive flow media such as crude oil due to a suitable choice of materials and a suitable construction. They are designed in structure and density so that they are freely transported in the flowing flow medium on the inlet side of the tube bundle heat exchanger into the chamber there and are distributed on the tube plate of the chamber in order to enter one of the tubes to be cleaned. They pass through the pipe to be cleaned under the pressure of the flow medium by entering the chamber on the inlet side of the shell-and-tube heat exchanger at the inlet of the pipes and leaving the pipes at the outlet after the passage. The entire inner wall of the pipe is cleaned intensively when the contact surface of the cleaning body comes into contact with the entire surface of the inner wall of the pipe as it passes through the pipe and is pressed against the inner wall of the pipe under the action of a contact pressure.
• the contact surface of the cleaning body is designed such that it detects and releases deposits adhering to the inner pipe wall such as coking, dirt particles or the like, so that these can be carried along by the flow medium and / or the cleaning body itself and can be discharged from the pipe. In this way, no coating in the sense of a longer-lasting deposition of can build up on the inner tube wall Form dirt particles. Incrustations on the inside of the pipe are also avoided.
• the cleaning bodies are collected after they have passed through the tubes and, if necessary, are fed to the inlet openings of the tubes for a further cleaning cycle through the tubes.
• the cleaning bodies may be returned to the inlet side of the heat exchanger immediately or only at a later point in time. It is essential that the cleaning bodies are not fed to individual collecting devices on the outlet side, but that the cleaning bodies are collected and returned together to the inlet side, at least in a common way, which does not require complex interventions or measures for return.
• the cleaning bodies are guided in a continuous or discontinuous cycle, namely after they have passed through the pipes, they are collected in a catching device and either fed directly back to the inlet side of the pipes for a new pass, or are first collected in a receiving device, the cleaning of the Pipes interrupted and is only carried out again after a predetermined period of time or depending on the degree of contamination of the pipes or other parameters.
• This system variant is very important because it allows automatic continuous or discontinuous return of the cleaning bodies, so that overall a very simple and very efficient cleaning of the inner wall of the tubes results without a considerable constructional effort is required.
• a catch device for example a fixed or movable sieve, or a filter for collecting the cleaning bodies from the media stream is provided for the cleaning bodies behind the outlet sides of the heat exchanger.
• Stationary safety devices such as filters or fixed sieves, usually span the entire cross-section of the drain lines on the outlet side of the heat exchanger.
• Movable screens can be switched between a neutral position in which they allow the entire medium flow with all components to pass through, and a collecting position in which they span the entire cross-section of the medium discharge line for collecting the cleaning bodies.
• a lock for filling and removing the cleaning bodies is connected downstream of the respective catching device.
• the lock can also be used for the intermediate storage of the cleaning bodies while the pipe cleaning is interrupted.
• the property of the cleaning bodies is important to sink or rise in the standing flow medium. This makes it easy to separate the cleaning bodies from the flow medium for storing them in locks or the like.
• the invention also includes cleaning bodies for systems for cleaning tubes of heat exchangers, in particular tube bundle heat exchangers, which have a plurality of tubes arranged parallel to one another between two chambers and through which a flow medium, in particular crude oil, with a temperature above 120 ° C. flows , wherein the cleaning bodies are designed such that for cleaning the tubes of the heat exchanger deposits on the inner wall such as coking, dirt particles or the like are removed by cleaning and discharged from the tubes when the cleaning bodies pass through the tubes.
• a flow medium in particular crude oil
• cleaning bodies according to the invention are primarily used in tube-bundle heat exchangers, but it is obvious that such cleaning bodies can also be used in single-tube heat exchangers. Conversely, cleaning bodies designed for single-tube heat exchangers are in no way suitable, as shown above, for use in tube-bundle heat exchangers.
• the cleaning body according to the invention is preferably designed as an essentially spherical, elastic rolling body with a cleaning surface, the entire surface of the cleaning body forming the contact surface for cleaning deposits off the inner wall of the tube.
• This shape and design of the cleaning body according to the invention is distinguished by very significant advantages. On the one hand, because of its spherical shape or its spherical shape, the body does not have to be directionally inserted into the pipe inlet of the pipe to be cleaned, but the cleaning body automatically adapts to the free internal cross section of the pipe in every position after entering the pipe without special measures being taken.
• the spherical shape provides a high cleaning potential. Because of its elasticity, the cleaning body can adapt to any change in the shape of the free cross-section of the pipe to be cleaned, which is possible in practice, for example if there is incrustation as a result of unexpectedly high current contamination of the flow medium. Cylindrical cleaning body like the prior art, on the other hand, are unsuitable for use in shell-and-tube heat exchangers.
• the outside diameter of the cleaning body in the pressure-free state namely before the entry of the cleaning body into the tube, is larger than the inside diameter of the tube, and the outside diameter of the cleaning body adapts to the inside diameter of the tube when the cleaning body enters the inlet opening of the tube and is compressed elastically resilient.
• the contact pressure with which the contact surface of the cleaning body comes into engagement with the inner wall of the tube is generated by a correspondingly elastic, resilient structure of the cleaning body.
• the cleaning body is given a larger outside diameter than the inside diameter of the pipe in the pressure-free state.
• Cleaning bodies according to the invention can be used in a large number of different cleaning systems. It is thus possible to use cleaning bodies according to the invention for systems in which the cleaning bodies practically run back and forth in the pipe to be cleaned by reversing the direction of flow of the medium flow. For this purpose, due to the provision of a direction-switchable line system for the flow medium, a relatively high construction effort is required, as was already explained at the beginning. Nevertheless, this cleaning system is simplified considerably by using cleaning bodies according to the invention, because, as already mentioned, the cleaning body according to the invention does not have to be used in a directional manner.
• the cleaning bodies can be collected after a cleaning cycle on the outlet side of the pipes as a batch, ie as a quantity, and can be returned to the pipes for cleaning in a suitable manner, either by reversing the flow on the previous outlet side or by moving the cleaning bodies as a whole to the previous inlet side , which always remains the inlet side.
• the cleaning bodies according to the invention can be used with particular advantage in systems in which they are circulated continuously or discontinuously. To avoid repetition, reference is made to the corresponding systems according to the invention explained above.
• the cleaning body has a buoyancy element on the inside and a cleaning element on the outside.
• the buoyancy element is intended to ensure that the cleaning body is freely transported in the flowing medium stream, so that the cleaning body is distributed as possible, especially on the inlet side of the heat exchanger, that is to say in front of the tube sheet, so that the tubes are cleaned at approximately the same frequency.
• particular care must be taken to ensure that an overall density of the cleaning body is achieved which is matched to the density of the process medium, so that the cleaning body is freely transported in the flowing medium stream.
• care must be taken that the spherical or spherical contact surface is particularly suitable for cleaning deposits or dirt particles or the like deposited on the inner wall of the pipe and is correspondingly abrasive.
• the buoyancy element is arranged in the center of the cleaning body and consists of one or more pressure-resistant or pressure-resistant hollow bodies, e.g. made of metal or bodies with a low specific weight, e.g. There is metal foam.
• the required compressive strength depends primarily on the relatively high system pressure, which e.g. in crude oil heating systems.
• the contact surface of the cleaning element must above all have an abrasive effect so that deposits can be cleaned off the inner tube wall.
• the cleaning element should also be designed to be resiliently elastic, so that a corresponding contact pressure is generated between the contact surface and the inner wall of the tube when the cleaning body enters the tube. Because of the resiliently elastic properties of the cleaning element, the immediately effective section of the spherical or spherical contact surface can correspond to a narrow, band-shaped flattening which extends circularly around the cleaning body and is in engagement with the inner tube wall.
• a resiliently elastic binding material such as metal foam carries the cleaning element and alone causes the necessary resilient behavior of the cleaning body. Rather, the necessary elasticity is generated jointly by the binding material and the cleaning element.
• the cleaning element can also be partially or completely embedded in the binding material.
• the contact surface of the cleaning body can be cleaned before it is re-supplied to the inlet side of the heat exchanger eg by high-pressure blasting of the contact surface of the cleaning bodies, and / or by mechanical means such as brushes or the like.
• the cleaning bodies can be checked at any time for wear or damage or the like on the way of the cleaning bodies from the outlet side of the heat exchanger to the inlet side.
• the cleaning bodies each consist of at least one front buoyancy element, as seen in the flow direction of the flow medium in the tube, and a cleaning element fastened to the rear side thereof, immovably or movably relative to the buoyancy element.
• the functions “buoyancy” and “cleaning” are divided into two separate sub-bodies, even if the two sub-bodies are combined to form a cleaning body.
• the weight of the cleaning element must also be taken into account when designing the buoyancy element.
• the buoyancy element first enters the pipe to be cleaned and takes the cleaning device attached to its back. supply element with.
• the buoyancy element has a spherical or spherical shape and takes on the function of a floating body which is formed from one or more cavities or with a correspondingly porous structure.
• the diameter of the buoyancy element is expediently mine than the inside diameter of the tube, so that the buoyancy element can easily enter the tube inlet and pass through the tube as freely as possible.
• the cleaning element of this cleaning body is preferably sheet-shaped or disk-shaped and circular in shape from spring sheet metal and carries a ring made of resiliently resilient lamellae, which lies as a contact surface on the inner tube wall.
• the diameter of the lamellar ring is consequently larger in the free state than in the tube if the lamellar ring is elastically compressed to the inside diameter of the tube and thus the necessary contact pressure is generated.
• the pressure of the flow medium mainly acts on the cleaning element in order to push the cleaning body together with the flow medium through the pipe.
• the front buoyancy element can also serve as a propulsion body, for example by keeping the circular gap between the outside of the buoyancy element and the inner tube wall relatively narrow.
• connection between the buoyancy element and the cleaning element allows a limited radial relative movement and preferably a limited relative axial movement of the buoyancy element and the cleaning element. It has been shown that this articulated connection with radial and axial play between the cleaning element and the buoyancy body supports the alignment and the entry of the cleaning body into the tubes of the tube bundle heat exchanger.
• the cleaning element preferably has cloverleaf-shaped lamellae, which are separated by a wide slot are separated from each other and have rounded corners. This form of the cleaning element separates the lamellae from one another, so that the lamellae cannot become jammed at the pipe ends or the like.
• a buoyancy element is arranged on both sides of the cleaning element.
• one of the two spherical or pear-shaped buoyancy bodies is always located in the flow direction at the front, so that the cleaning body on the tube plate can easily enter one of the tubes and pass through in an aligned position.
• the aforementioned articulated connection between the cleaning element and the two buoyancy bodies is also preferred.
• the cleaning bodies according to the invention are designed in their overall density and in their shape so that the cleaning bodies in particular in the flowing flow medium with large flow cross sections such. B. can be transported freely in the chambers of the tube bundle heat exchanger. As a result, the cleaning bodies are distributed in the turbulent flow in the chamber at the inlet in front of the tube sheet of the tube bundle heat exchanger.
• the material of the cleaning element and the material of the binding material, if one is used, and the material of the buoyancy element are temperature-resistant (min. 120 ° C.) and resistant to aggressive media such as crude oil and are preferably made of metal.
• FIG. 1 is a schematic representation of an embodiment of a tube bundle heat exchanger system with a system for cleaning tubes of heat exchangers, in which the tubes pass through cleaning bodies and the cleaning supply body in the system in a cycle;
• FIG. 1 a shows a schematic illustration of a further exemplary embodiment of a tube bundle heat exchanger system as in FIG. 1, but with an alternative embodiment of a lock used for the circulation of the cleaning bodies;
• Figure 2 is a schematic view of a first embodiment of a cleaning body in cross section.
• FIG. 3 shows a schematic view of a second exemplary embodiment of a cleaning body in cross section
• Figure 4 is a schematic view of a third embodiment of a cleaning body in cross section.
• FIG. 5 shows a schematic view of a fourth exemplary embodiment of a cleaning body
• FIG. 6 shows a view of a fifth exemplary embodiment of a cleaning body, partly as a sectional illustration
• FIG. 7 is a view of a raw part of the exemplary embodiment of a cleaning body according to FIG. 6;
• FIG. 8 is a sectional view of a sixth exemplary embodiment of a cleaning body, the cleaning body being formed in two parts;
• FIG. 9 shows a view of a seventh exemplary embodiment of a cleaning body in a sectional illustration in a two-part design in one of the pipes to be cleaned;
• FIG. 10 shows a front view of a cleaning element for use with a cleaning body of the design according to FIG. 9 and, in a corresponding adaptation, also according to FIG. 8;
• Fig. 11 is a view of an eighth embodiment of a cleaning body in a sectional view in three parts.
• the system shown purely schematically in FIG. 1 as an exemplary embodiment serves for heating a crude oil flow in a tube bundle heat exchanger 10, to which the crude oil is fed through a feed line 11 in the direction of arrow 12 with the support of a pump 13.
• the heat exchanger 10 conventionally comprises a bundle of approximately 100 to 500 tubes 5 arranged between two chambers 10a, 10b, in which the crude oil is heated up with the process heat which acts on the crude oil through the tube wall when the tubes 5 passes.
• the crude oil is discharged via the line 14 in the direction of the arrow 15 and is fed to the next processing stage - as a rule the final heater.
• the temperature of the crude oil passed through the plant can be, for example, in the range from 120 ° C. to 400 ° C.
• cleaning bodies are provided, which are indicated in FIG. 1 and la as small circles in the chambers 10a, 10b and are explained in more detail with reference to other figures .
• the cleaning bodies are distributed in a turbulent flow of the flow medium in the chamber 10a on the tube sheet of the heat exchanger 10 in such a way that at least one cleaning body enters the inlet of each tube 5 during several cycles.
• the cleaning bodies pass through the pipe 5 to be cleaned in each case freely under the pressure of the crude oil flow by entering at the inlet of the pipe 5 and leaving the pipe 5 after passing through the outlet in the chamber 10b.
• the entire inner wall of the pipe is cleaned intensively.
• FIG. 1 serves primarily a preferred embodiment of the system according to the invention, according to which the cleaning bodies are guided in a continuous or discontinuous cycle.
• the cleaning bodies are first taken out of the crude oil flow of line 14 with a safety device 16 and discharged through a line 17 in the direction of arrow 18, while the crude oil flow leads the system without a cleaning body via a discharge line 15a leaves again.
• a filter can be provided in the catching device 16 as a stationary catching device, which spans the entire cross section of the catching device 16.
• movable or fixed sieves - indicated by the dashed line 16a in FIG. 1 - can also be used as a catching device 16. The sieves can be switched between a neutral position in which they allow the entire crude oil flow to pass and a collecting position in which they span the entire cross section of the catching device 16 and remove the cleaning bodies from the crude oil flow.
• the cleaning bodies are fed directly from the line 17 into the feed line 11 in the circuit (not shown).
• the cleaning bodies are passed through line 17 to a collecting device, namely a lock 19, in which they are collected and fed back into the feed line 11 via the line 30 and a non-return valve 40 in the direction of the arrow 41 at a predetermined time.
• a collecting device namely a lock 19, in which they are collected and fed back into the feed line 11 via the line 30 and a non-return valve 40 in the direction of the arrow 41 at a predetermined time.
• the lock 19 is divided into an upper chamber 20 and a lower chamber 21, which are separated from one another by a floor 22.
• an opening 23 which is closed by a flap 24 which can be pivoted about an axis 25 when the cleaning bodies are collected in the upper chamber 20.
• a bypass 26 which starts from the upper chamber 20 and with its other end in a certain position to the lower Chamber 21 is connected, there is a pump 28, the crude oil coming from the line 17 via a wire basket 29 or the like, which does not allow cleaning bodies, feeds from the upper chamber 20 into the lower chamber 21 such that the jet entering there, such as is indicated by the double arrow, the flap 24 holds in the closed position of the opening 23 as long as the cleaning bodies are collected in the upper chamber 20. If the pump 28 is switched off, the flap 24 sinks into the open position shown in the drawing with dashed lines, so that the cleaning bodies pass from the upper chamber 20 into the lower chamber 21.
• the flap 24 is in the open position.
• the cleaning bodies are located in the lower chamber 21.
• the flap 24 swivels upward from the bypass line 26 into the closed position under the action of the crude oil flow directed against the flap 24.
• the cleaning bodies are conveyed by the crude oil flow from the bypass line 26 into the line 30, in which the non-return flap 40 is opened by the pressure of the flow medium at the beginning of the cleaning cycle, and from there back into the inlet line 11.
• cleaning bodies collected by the catching device 16 are transported through the line 17 back into the upper chamber 20 because the opening 23 is closed by the flap 24.
• the drive of the pump 28 is switched off.
• the crude oil jet from the bypass line 26 stops, so that the flap 24 swings back from the closed position into the open position under the effect of its gravity.
• the check valve 40 prevents the medium from flowing back.
• the cleaning bodies sink from the upper chamber 20 through the opening 23 into the lower chamber 21. There they remain until the beginning of the next cleaning cycle.
• the mode of operation described above with reference to FIG. 1 is used for sinking cleaning bodies, ie for cleaning bodies with a higher density than the operating medium (eg crude oil).
• an alternative design and mode of operation of the lock must be provided for cleaning bodies with a lower density, ie cleaning bodies that rise in the operating medium, possibly also crude oil.
• An exemplary embodiment of such a lock can be seen in a schematic representation in FIG. The following description is essentially limited to the structure and operation of the Lock.
• this lock 19 is divided into an upper and lower chamber 20, 21, which are separated from one another by a base 22.
• a base 22 In the bottom 22 there is an opening 23 which is closed by a flap 24 which can be pivoted about an axis 25 when the cleaning bodies are collected in the lower chamber 21.
• a bypass 26 which starts from the lower chamber 21 and is connected at its other end to the upper chamber 20 in a certain position, as in the first-mentioned embodiment, there is a pump 28, the crude oil coming from the line 17 via a wire basket 29 or the like, which does not allow cleaning bodies, feeds from the lower chamber 21 into the upper chamber 20 such that the jet entering there, as indicated by the double arrow, flap 24 against the spring force of a spring 24a in the closed position of the opening 23 lasts as long as the cleaning bodies are collected in the lower chamber 21. If the pump 28 is switched off, the flap 24 opens by the spring force into the open position shown in the drawing with dashed lines, so that the cleaning bodies rise from the lower chamber 21 into the upper chamber 20.
• the flap 24 is in the open position.
• the cleaning bodies are located in the upper chamber 20.
• the flap 24 swivels downward against the spring force into the closed position against the spring force under the action of the crude oil flow directed against the flap 24.
• the cleaning bodies are conveyed by the crude oil flow from the bypass line 26 into the line 30, in which the non-return flap 40 is opened by the pressure of the flow medium at the beginning of the cleaning cycle, and from there again into the inlet line 11.
• Cleaning bodies collected by the catching device 16 during such a cleaning cycle are transported through the line 17 back into the lower chamber 21 and collected here because the opening 23 is closed by the flap 24.
• a cleaning body la consists of a central, spherical hollow body as a buoyancy element 2 with an outer abrasive cleaning element 4 made of knitted metal, which is firmly connected to the buoyancy element 2 with the interposition of a metallic elastic medium 3.
• the connections of the components are made by conventional connection methods such as welding, gluing, soldering or the like.
• the buoyancy element 2 is relatively mine compared to the cleaning element 4, whose knitted metal fabric and the structure of the elastic medium 3 are relatively loose, so that the buoyancy element 2 compensates for a relatively low weight with regard to the desired overall density of the cleaning body 1 a Has.
• the density of the cleaning body 1 a is fundamentally to be matched to the density of the medium, unless circumstances exist which permit or even require a substantial difference.
• All parts of the cleaning body la are made of metal - with the exception of the adhesive, which can also consist of a highly heat-resistant plastic.
• the metal knitted fabric of the cleaning element 4 is made from polygonal wire or strip material made of stainless steel, the cleaning element 4 together with the elastic medium 3 giving the cleaning body 1 a necessary elastic resilient property.
• the elastic medium 3 consists of elastically resilient, wound metal lamellae or a correspondingly resiliently resilient metal braid, each of which is attached in a hollow spherical shape to the buoyancy element 2 - a pressure-tight hollow metal ball.
• the components of the cleaning body la are designed for process temperatures that can be up to 400 ° C, and they are resistant to an aggressive process medium such as crude oil.
• an aggressive process medium such as crude oil.
• the elastic medium 3 for example, a tubular mat made of spring steel wire mesh can also be used, the tube being soldered or welded, for example, at both ends for closing and fastening.
• the elasticity of this layer is essential so that the cleaning body is loaded Adjust the inner diameter of the pipe to be cleaned easily and still, when the cleaning body la passes through the pipe, can exert a pressure on the inner wall of the pipe which is sufficient to clean contaminants from the inner wall of the pipe.
• the metal knitted fabric or expanded metal of the cleaning element 4 is firmly connected to the elastic medium 3 by soldering or by another conventional connection method, as mentioned above.
• a blank thus formed is pressed into a spherical shape at the end.
• the spherical hollow body of the buoyancy element 2 is formed, for example, from two deep-drawn metal half-shells.
• the cleaning body 1b is formed from a pressure-resistant hollow metal ball as a buoyancy element 2 with an essentially spherical cleaning element 4 made of metal braid or of expanded metal made of spring steel and fastened directly thereon.
• the attachment to the buoyancy element 2 and a stabilization of the elastic material of the cleaning element 4 takes place e.g. by soldering. Since the cleaning element 4 is very elastic in this case, no additional elastic medium is used as in the first exemplary embodiment, and also in this case the buoyancy element 2 is comparatively mine in relation to the cleaning element 4.
• the cleaning element 4 which can be made of knitted metal or metal braid as in the previous exemplary embodiments, is attached to the spherical buoyancy element 2, for example by soldering, directly to the buoyancy element 2 and, moreover, in whole or in part embedded in the elastic medium 3, which can consist of a temperature-resistant elastomer or of elastic metal foam.
• the cleaning medium 4 and the elastomer are brought into the desired spherical shape in an injection mold and the elastomer is injected into the structure made of expanded metal or metal knitted fabric. This manufacturing process is particularly easy to carry out.
• welding, gluing, soldering or the like are also used here as connection methods.
• the cleaning body 1d does not have a separate buoyancy body 2, but instead there is a metal lamella, metal Knitted fabric or metal mesh or expanded metal cleaning medium 4 directly embedded in an elastic medium 3 consisting of elastic metal foam or temperature-resistant elastomer, which simultaneously acts as a buoyancy element 2.
• the buoyancy element 2 is also clearly mine than the cleaning element 4, and this cleaning body le is produced from the blank le 'shown in FIG.
• a round blank 5 made of spring steel, slotted on the outside, as shown in FIG. 7, is soldered onto the metal ball of the buoyancy element 2, e.g. is indicated at 6.
• two round halves 5a are soldered onto the buoyancy element 2 at an angle of 90 ° with respect to the round blank 5, whereupon semicircular or quarter-circle shaped circle segments 5b are arranged and soldered in the remaining spaces on the buoyancy element 2 in the symmetrical manner shown in FIG.
• the weight is designed such that the density of the cleaning body is matched to the density of the medium, so that the cleaning bodies can be freely transported in the media flow and are distributed in particular in the area of the tube plate of the heat exchanger 10. when the cleaning bodies are to be fed into the pipes 5 to be cleaned. Possible exceptions have been pointed out in the description of the first exemplary embodiment.
• the cleaning bodies are fed via the feed line 11 for the crude oil flow on the inlet side of the heat exchanger 10 and thus get into the chamber 10a and thus into the area in front of the tube sheet of the heat exchanger 10. If there the crude oil flow is divided between the individual tubes 5 of the heat exchanger 10, the cleaning body la-ie are easily taken along so that they enter the inlet of one of the pipes 5 of the heat exchanger 10 to be cleaned.
• the cleaning bodies are compressed in a resilient manner until the inside diameter of the pipes is reached.
• a contact pressure is thus generated which is necessary to press the contact surface, that is to say the outer surface of the cleaning elements 4 of the cleaning bodies, against the inner wall of the pipes 5 to be cleaned. Under the action of the contact pressure, deposits of dirt particles or the like are cleaned off the inside wall of the pipe when the cleaning bodies pass through the pipes 5, the flow pressure of the flow medium acting as a driving force on the cleaning bodies.
• the cleaning body if is formed in two parts.
• a - in the direction of flow S - front approximately pear-shaped or spherical, but preferably spherical, hollow metal body as buoyancy element 2, as a cleaning element 4, a Meislake and leaf-shaped disc made of spring plate with a thickness of about 0.05-0.5 mm in the center, as shown , for example by welding or soldering.
• the required strength or stability determines the minimum thickness of this disc, the diameter of which is larger than the inside diameter of the pipes 5 to be cleaned.
• the fins 4a of the cleaning element 4 can have deposits such as dirt particles or the like from the inner wall of the tube
• the density of the cleaning body is also matched to the density of the flow medium.
• the cleaning body if is designed with regard to the selection of the metal and the connection between the buoyancy element 2 and the cleaning element 4 for operating temperatures of approximately 400 ° C. as well as with regard to the chemically aggressive properties of crude oil, which forms the flow medium. In practice it has been shown that the two-part cleaning body if, as shown for example in FIG.
• the cleaning bodies if in the catching device 16 can also be removed from the crude oil flow of the line 14 and discharged into the line 17 as well as either directly fed back into the feed line 11 for continuous cleaning of the tubes of the tube bundle heat exchanger and of the heat exchanger 10 of the one shown in FIG 1 system or via line 17 into the lock 19 provided as a collecting device and from there feed it back into the feed line 11 at the appropriate time.
• the disk of the cleaning element 4 can be made thicker in the middle than outside. Because the required elasticity for the purpose of adaptation to the inner diameter of the tube 5 is to be applied exclusively from the outer edge of the cleaning element 4.
• the hollow body or the ball of the buoyancy element 2 can, moreover, be made substantially mine than in the example shown in FIG. 8. It should also be pointed out that in the case of the cleaning body if the block in the tube 5 required for generating the necessary differential pressure is taken over solely by the disk of the cleaning element 4. This feature is also important for the automatic alignment of the cleaning body if.
• the seventh exemplary embodiment shown in the cleaning position in the tube 5 in FIG. 9 differs from the cleaning body if of FIG. 8 primarily in that the buoyancy body 2 is connected to the cleaning element 4 in a non-rigid but movable manner.
• a pin 7 is fastened to the buoyancy body 2, which extends through a central opening 8 in the cleaning element 4 and at its free end a disc 9, as shown, as an axial limitation of a relative mobility of the buoyancy element 2 with respect to the cleaning element 4 in the axial direction Direction is fixed.
• a relative mobility of the buoyancy body 2 and the cleaning element 4 in the radial direction is permitted in that the diameter of the opening 8 is larger than the diameter of the pin 7. It has been shown that this gelenMge connection between the float 2 and the cleaning element 4 facilitates the entry of the cleaning body ig into the tube 5 and the cleaning body ig assumes the position shown in the drawing as it passes through the tube 5.
• a leaf-shaped disc made of spring plate according to FIG. 10 is preferred for the execution of the cleaning body if and ig and also lh.
• the resilient slats 4a are separated from one another by a wide slot 4b and have rounded corners 4c in order to avoid any risk of jamming adjacent slats 4a, e.g. B. to avoid a pipe socket or the like.
• In the middle is the opening 8 for the pin 7 of the buoyancy body 2.
• the eighth embodiment of a cleaning body 1h according to FIG. 11 differs from the embodiment according to FIG. 9 in that two buoyancy bodies 2 are present, so that a buoyancy body 2 is arranged on both sides of the cleaning element 4.
• the pin 7 connects the two buoyancy bodies 2 and at the same time establishes the connection to the cleaning element 4, specifically with a limited radial and axial relative mobility of the buoyancy bodies 2 with respect to the cleaning element 4a, as in the exemplary embodiment according to FIG. 9.
• the cleaning element 4 adapts to the inside diameter of the pipe 5 to be cleaned, so that deposits are cleaned off.
• FIGS. 1 and 1a and the described modes of operation are only to be understood as pure exemplary embodiments, to which the invention is in no way limited.
• the cleaning bodies according to the invention can be used not only in plants for processing crude oil but also in other plants which are operated in high temperature ranges above 120 ° C.
• the cleaning bodies are also suitable for cleaning evaporator tubes in seawater desalination plants and other high-temperature applications.
• the cleaning bodies can also be used for special applications with aggressive media in the chemical industry.
• cleaning bodies according to the invention can also be used in pipe systems which are operated in temperature ranges below 120 ° C.
• the frequent mention of a working temperature above 120 ° C in the above description and in the claims is based on the fact that the cleaning bodies according to the invention are primarily intended for heat exchangers through which crude oil flows as a medium in the high temperature range, without the use of cleaning bodies according to the invention for this application is limited.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• General Engineering & Computer Science (AREA)
• Cleaning In General (AREA)
• Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
• Vehicle Body Suspensions (AREA)

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• 2002
  • 2002-11-05 DE DE10251736A patent/DE10251736A1/de not_active Withdrawn
• 2003
  • 2003-10-31 AU AU2003276222A patent/AU2003276222A1/en not_active Abandoned
  • 2003-10-31 AT AT03810424T patent/ATE412158T1/de not_active IP Right Cessation
  • 2003-10-31 DE DE50310682T patent/DE50310682D1/de not_active Expired - Lifetime
  • 2003-10-31 EP EP03810424A patent/EP1565702B1/fr not_active Expired - Lifetime
  • 2003-10-31 WO PCT/EP2003/012136 patent/WO2004042314A1/fr not_active Ceased

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