1. Field of Invention
This invention relates generally to the cleaning of heat exchangers, and more particularly, to an apparatus and system for removing residue which accumulates over time in heat exchangers and other tubing and piping used in industrial facilities.
2. Description of the Related Art
Heat exchangers are commonly used in industrial facilities. Over time, these heat exchangers tend to develop residue on the surfaces of the tubes, tube sheets, tube support plates and other internal structural parts. The residue can comprise adherent films, scales, sludge deposits, corrosion and/or other similar materials. Over time, this residue can have an adverse affect on the operational performance of the exchangers. The same problem can arise for all piping and tubing found in industrial facilities.
Various cleaning devices and methods have been developed to remove this residue buildup from heat exchangers, tubes and other piping. A common method involves the controlled application of high pressure water and/or chemical streams to the affected areas of the heat exchanger. This method can require the presence of one or more persons at or near the point of application of the high pressure stream to the exchanger during the cleaning process.
For example, an operator may stand in clear view of, and near the line-of-fire of, the high pressure stream to direct the stream to the affected areas of the exchanger. Another person may be needed to operate a control panel next to the exchanger to further control the direction and volume of stream flow. This type of work is extremely labor intensive and potentially hazardous. For example, it may be necessary for crews to manually reposition the device providing the high pressure stream for each cleaning stroke. Further, those persons in close proximity to the cleaning environment can be exposed to high pressure water, hazardous cleaning chemicals or other potentially toxic, poisonous or volatile materials.
In accordance with the illustrative embodiments hereinafter described, an automated heat exchanger tube cleaning assembly and system are provided. In an embodiment, the system can automatically (without ongoing human intervention) survey the tube sheet of a heat exchanger in three dimensions, convert and record the survey results as a digital file in three dimensions, and then, according to sequential parameters input via custom software, automatically coordinate via computer one or more cleaning devices such as lances to effect the cleaning of each desired tube of the heat exchanger.
In an illustrative embodiment, a system for cleaning tubes in a heat exchanger may include a scanning device for capturing three dimensional coordinates corresponding to the location of the tubes in the heat exchanger to be cleaned, a heat exchanger tube cleaning lance, a heat exchanger tube cleaning lance positioning device, and a motion control computer for controlling the motion of the heat exchanger tube cleaning lance positioning device with respect to the tubes in the heat exchanger based upon the three dimensional coordinates captured by the laser surface scanning device. In an illustrative embodiment, the scanning device can be a sensor. Further, the sensor can be, for example, a laser.
A command console may be in operational connection with the motion control computer for controlling the motion of the heat exchanger tube cleaning lance positioning device from a remote location. The system may function as a completely automated system or a remote controlled system, as desired. A pumping station may supply cleaning materials (including, but not limited to, high-pressure water to approximately 50,000 PSI) to the heat exchanger tube cleaning lance. The respective structures and movements of the heat exchanger tube cleaning lance and the laser surface scanning device may be independent of each other.
In another illustrative embodiment, a method of cleaning one or more tubes in a heat exchanger is provided. The method can include, for example, the steps of digitally surveying the heat exchanger tube sheet in three dimensions to determine the location of the heat exchanger tubes, positioning a tube cleaning device adjacent to the heat exchanger tube sheet, and aligning the tube cleaning device with the heat exchanger tubes based upon the tube locations determined by the digital survey. The survey results obtained from the digital survey may be stored in a motion control computer. Each of the steps of digitally surveying, positioning, and aligning may be controlled by a motion control computer. Further, the location of the motion control computer may be remote from the location of the tube cleaning device.
In another illustrative embodiment, a recalibration system and related method are provided that allow for automatically recalibrating the position of a cleaning lance with respect to one or more heat exchanger targets. The computer motion controller may, in accordance with user-defined time intervals or as a result of a missed target, move the tip of the cleaning lance to a three dimensional coordinate value known by the computer to be the position of a recalibration sensor. The recalibration sensor may be temporarily rigidly fixed to the heat exchanger shell during identification of the initial three dimensional coordinate point having a specific coordinate value. This three dimensional coordinate value can be measured and delivered to the computer prior to starting the cleaning. When the lance tip is at the coordinate point, and assuming no shifting of the lance tip relative to the exchanger has occurred, the computer may receive an input signal from a sensor or set of sensors that have detected the lance tip and confirmed that it is in the proper location, such as, for example, through the use of thru-beam optical sensors, non-contact proximity sensors, contact proximity sensors, or digital imaging sensors. If the lance has shifted, then a different input signal can be received, and repositioning information may be obtained by the nature of the signal such that the computer may make the slight adjustment of the lance's position relative to the recalibration sensor, and then move to the 3-D point again to confirm recalibration has been successful. The computer controller may then move back to the next cleaning target and resume the cleaning operation.
In another illustrative embodiment, a system for cleaning one or more tubes on the tube sheet of a heat exchanger is provided. The system can include a display for presenting a map of at least a portion of the tube sheet, a user input device for defining a cleaning region on the map and for identifying at least one tube within the cleaning region, a tube cleaning lance for accessing one or more tubes on the tube sheet, a tube cleaning lance positioning device for maneuvering the tube cleaning lance, and a motion control computer for navigating the motion of one or more of the tube cleaning lance and the tube cleaning lance positioning device with respect to the tubes on the tube sheet by utilizing information received from the user input device.
The user input device can be one or more of a touch screen, a joystick controller, a mouse and a trackball. The tube cleaning lance can access the one or more tubes on the tube sheet in any order desired, for example, simultaneously or sequentially. The motion control computer can be communicatively coupled to a remote monitoring device via a communications network. The location of the motion control computer can be a remote distance from the location of the tube cleaning lance positioning device. A pumping station can be operationally controlled by the motion control computer for supplying cleaning materials to the tube cleaning lance.
In another illustrative embodiment, a method of maneuvering a heat exchanger tube cleaning device with respect to a tube sheet of a heat exchanger is provided. A map of at least a portion of the tube sheet can be provided. User input can be accepted regarding a plurality of reference points within the map, the plurality of reference points defining the location of a plurality of tubes to be cleaned on the tube sheet. The motion of the tube cleaning device can be navigated with respect to the plurality of reference points. The navigation may be manual or automatically controlled.
In another illustrative embodiment, a method of maneuvering a heat exchanger tube cleaning device with respect to a tube sheet of a heat exchanger is provided. A map of at least a portion of the tube sheet can be provided. User input can be accepted regarding a plurality of reference points within the map, the plurality of reference points defining the perimeter of a cleaning region with one or more tubes to be cleaned located therein. The motion of the tube cleaning device can be navigated with respect to the plurality of reference points and the one or more tubes located within the cleaning region. The navigation may be manual or automatically controlled.
In another illustrative embodiment, a method of cleaning one or more tubes on the tube sheet of a heat exchanger is provided. A tube cleaning device can be positioned adjacent to the tube sheet. A map can be provided of at least a portion of the tube sheet. User input can be accepted on a motion control computer regarding a plurality of reference points on the map, the plurality of reference points corresponding to a plurality of tubes on the tube sheet that define the perimeter of a cleaning region. The motion of the tube cleaning device can be navigated to the plurality of tubes on the tube sheet that define the perimeter of the cleaning region. The navigation may be manual or automatically controlled. The tube cleaning device can be instructed to clean the plurality of tubes on the tube sheet that define the perimeter of the cleaning region. The location of one or more tubes located within the cleaning region may be identified. The motion of the tube cleaning device can be navigated to the one or more tubes located within the cleaning region using the motion control computer. The tube cleaning device can be instructed to clean the one or more tubes located within the cleaning region. The motion of the tube cleaning device can be automatically navigated to the plurality of tubes on the tube sheet that define the perimeter of the cleaning region or to the one or more tubes located within the cleaning region using the motion control computer.
In another illustrative embodiment, a method of cleaning one or more tubes on the tube sheet of a heat exchanger is provided. A tube cleaning device can be positioned adjacent to the tube sheet. A map may be provided of at least a portion of the tube sheet. User input can be accepted on a motion control computer regarding a plurality of reference points on the map, the plurality of reference points corresponding to a plurality of tubes that define the perimeter of a cleaning region. The location of one or more tubes located within the cleaning region can be identified. The motion of the tube cleaning device can be navigated to the plurality of tubes that define the perimeter of a cleaning region and the one or more tubes located within the cleaning region using the motion control computer. The navigation may be manual or automatically controlled. The tube cleaning device can then be instructed to clean the tubes.
While certain preferred illustrative embodiments will be described herein, it will be understood that this description is not intended to limit the invention to those embodiments. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
Referring now to
Operations of assembly 10 can be controlled by a control console 20, as illustrated in
In a specific illustrative embodiment, control console 20 is located in a command trailer 40 (
Control console 20 can be integrated with a command station 44 within trailer 40. Command station 44 can include, in addition to control console 20, video monitor screens 46 and appropriate dials, switches and other instruments for controlling the operation of assembly 10 and its related features and components.
One or more video cameras 30 (
In an illustrative embodiment, a series of four cameras 30a, 30b, 30c, & 30d can feed images to command station 44. The cameras 30a, 30b, 30c, & 30d preferably have full remote-control pan, tilt, and zoom as well as near-infrared capability and completely waterproof enclosures. Two cameras 30a, 30b can display the work at the exchanger tube sheet in close-up detail to, for example, allow a process operator to safely watch the work as it occurs and/or to guide him in real time if he elects to control the cleaning process from a remote location. Third camera 30c can display the entire exchanger 12 and assembly 10. Fourth camera 30d can be positioned atop command trailer 40 to display the area around a pump 60 and trailer 62. Pump 60 disposed on trailer 62 supplies pressurized cleaning materials to assembly 10 via tubing 64. Cameras 30a, 30b, 30c and 30d can be moved or repositioned as necessary to obtain the desired view of the system.
In an illustrative embodiment, a pan and tilt joystick controller 70 (
A guide tube 94 (
Control panel 20 can be used to regulate the movement of cleaning lance 90. For example, control panel 20 can control the distance that cleaning lance 90 extends out of, or retracts into, guide tube 94, or the rotational speed of lance 90 within tube 88. Also, control panel 20 can independently control the movement of one or more of guide tube 94, cleaning lance 90 and/or assembly 10. Also, control panel 20 can include indicators for lance revolutions per minute (RPM) and feet per second (FPS), as well as closed-loop feedback control circuit for positioning assembly 10. These types of indicators can allow for semi-automated control of motion parameters for lance 90 via, for example, programmable set-points for minimum and maximum allowable lance speed (linear and angular) and position.
Control panel 20 can also be used to regulate the operations of pump 60, or any other pumps utilized in connection with assembly 10. For example, an operator may start and stop pump 60 and have access to information regarding pump operations via control panel 20.
In an illustrative embodiment, cleaning lance 90 and guide tube 94 can be housed within a heat exchanger tube cleaning lance positioning device 91 (FIGS. 1 & 11-12) that can be part of assembly 10. Joystick controller 70 can also preferably control the movements of device 91. One or more of cleaning lance 90 and guide tube 94 can be manipulated and positioned for cleaning each tube 88 of exchanger 12 by using heat exchanger tube cleaning lance positioning device 99. Device 91 can be any device that is integrated with assembly 10 and can be used to control and maneuver the movements of one or more of lance 90 and guide tube 94 and fall within the present illustrative embodiments. Assembly 10 can be disposed within a frame 95, if desired (
As illustrated in
In an illustrative embodiment, scanning device 100 can be mounted upon tube sheet 80 of exchanger 12 using scanning mount 102 (
Tube sheets 80 can be optically scanned by scanning device 100, and the scanned images can be delivered to motion control computer 120 (
In an illustrative embodiment (see
After the initial scan has occurred, a centering jig 140 (as shown in
Joystick controller 70 can be utilized to position tip end 92 of cleaning lance 90 at the center of a minimum of three unique targets at the surface of tube sheet 80. Motion control computer 120 can determine the orientation of jig 140 relative to the previously stored x-y-z coordinates and calculate the most desirable location for cleaning lance 90.
Scanning device 100 (See
In an illustrative embodiment, a recalibration disc 150 as shown in
The front face of recalibration disc 150 can be sanded flat until the conductor of each wire in recalibration disc 150 is exposed as a conductive point on the flat plane. The wires can extend out of recalibration disc 150 on the backside and be chemically soldered into one half of a multi-conductor electronics plug. Recalibration disc 150 can then be silicone-bedded into a corresponding stainless steel cup, with the contact plane facing the open side and the connector plug protruding from the back. A removable snap-on face plate 152 can cover the contact side of recalibration disc 150.
In an illustrative embodiment, face plate 152 can have a plurality of small, spring loaded stainless steel pins 154 installed individually from the inside thereof. When face plate 152 is in place, an individual pin 154 can be positioned over each contact wire, and in the normal position the spring tension preferably does not allow pin 154 and the contact wire to touch. If a positive external force is applied to the outer surface of plate 152 and parallel to the wires in the bundle, the particular stainless pins 154 under the load can slide down and make contact with the wires under them.
As illustrated in
As illustrated in
Upon initial set-up and after scanning device 100 has gathered its three dimensional coordinates and determined its current positioning relative to those coordinates, assembly 10 can be instructed by motion control computer 120 to begin an initial calibration procedure. Cleaning lance 90 can then be manually guided via control console 20 until positive polarity probe 200 on guide tube 94 makes contact with the center conductor pin 154 of recalibration disc 150. This contact can trigger motion control computer 120 to recall the x-y-z coordinates for this point, and recognize that these coordinates should always result in an input signal from the center wire. Scanning device 100 can periodically re-check the coordinates to confirm the signal.
If positive polarity probe 200 on guide tube 94 does not make contact with the center conductor pin 154 of recalibration disc 150, it can contact one or more of several hundred other pins resulting in a different input. At this point, motion control computer 120 can recognize exactly where positive polarity probe 200 is located relative to center conductor pin 154 due to the known geometry of the conductor spacing, and can deliver an appropriate output to the x-y-z motion system (the servomotors that control all motion) to attempt to hit center conductor pin 154 only. Motion control computer 120 can continue this trial-and-error loop until it once again finds center conductor pin 154, and may then realign the 3-D coordinate system with an updated spatial orientation. This recalibration procedure can occur at user-defined intervals and/or anytime a torque spike is encountered near the plane of tube sheet 80. In an illustrative embodiment, the process can take less than ten seconds in practice, as machine movement can exceed five g's acceleration and five meters per second velocity. Once recalibration is complete, motion control computer 120 can once again find the precise center of each target every time.
In an illustrative embodiment, a method of cleaning tubes in a heat exchanger is also provided. The method can include, for example, the steps of digitally surveying the heat exchanger tube sheet in three dimensions to determine the location of the heat exchanger tubes, positioning a tube cleaning device adjacent to the heat exchanger tube sheet, and aligning the tube cleaning device with the heat exchanger tubes based upon the tube locations determined by the digital survey. In an illustrative embodiment, a possible additional feature may include storing the survey results obtained from the digital survey in a motion control computer. Another possible additional feature may include each of the steps of digitally surveying, positioning and aligning being controlled by a motion control computer.
In an illustrative embodiment, a system for cleaning tubes in a shell and tube heat exchanger is provided. The system can include a laser surface scanning device 100 for capturing three dimensional coordinates corresponding to the location of the tubes 88 in the heat exchanger 12 to be cleaned, a heat exchanger tube cleaning lance 90, a heat exchanger tube cleaning lance positioning device 91, and a motion control computer 120 for controlling the motion of the heat exchanger tube cleaning lance positioning device 91 with respect to the tubes 88 in the heat exchanger 12 based upon the three dimensional coordinates captured by the laser surface scanning device 100.
In an illustrative embodiment, the system can recognize any potential collisions with personnel or equipment during the motion sequence and reverse direction before any injuries to personnel or damage to equipment occur. The servomotors can automatically and constantly relay torque information to the motion control computer 120, and the motion control computer 120 can use this information in accordance with how it is programmed by the user.
In the event of a torque spike in the z-axis during cleaning due to a plug in a tube target, the system can be programmed to, for example, abandon the tube target and move to the next tube target, or alternatively, withdraw cleaning lance 90 slightly and enable the high-pressure jets to cut away the plug within the tube target for a user defined time period, then try again to pass through the plugged area. This process can be repeated until the target area is clean or until a user defined number of attempts have been tried unsuccessfully. The system can also allow for the jet pressure to be raised to a user defined maximum as required to successfully cut through difficult areas.
The system can integrate function, control, and vital signs for pump 60 and the related high pressure jets of cleaning lance 90 with motion control computer 120. The system can allow for complete control of all pump functions, including engine start/stop, engage/disengage power take off (“PTO”), water supply valve on/off, raise/lower pressure, and high-pressure by-pass on/off. The system can also allow a user to monitor and adjust pump vitals such as water temperature, oil pressure, and voltage. This integration of pump 60 and the related high pressure jets of cleaning lance 90 with motion control computer 120 avoids the necessity for constant human interface at the location of the cleaning equipment and allows for a more efficient cleaning sequence.
In an illustrative embodiment, the system can be shut down or warnings can be initiated by motion control computer 120 if user defined thresholds are crossed. For example, the system can incorporate a safety light curtain as a safety barricade. The curtain can be multi-layered. If the curtain is encroached, the system may initiate an audible and visual alarm and/or shut down all high-pressure and motion, depending on what layer of intrusion has been encountered. In the case of a full breach with shutdown, a user with security credentials may then be required to declare the threat of injury passed and begin the restart procedure.
The system of the present invention can be operated continuously using shifts of operators to clean exchangers 12 quickly. Further, the system can incorporate networking and report generation capabilities. For example, assembly 10 can be linked to a local area network (“LAN”) and/or a secure server via wireless Internet to provide customers and/or operators with information regarding the job being performed. In an illustrative embodiment, motion control computer 120 can be communicatively coupled to a remote monitoring device via a communications network. This information can include, for example, real-time job progress, estimated time of completion, estimated cost at completion, current cost, current percent complete, and average time per tube. The system can also auto-generate a post-job report upon completion, which provides details about all events and activities that took place at each cleaning site. For example, the report can include a visual map of exchanger 12 relating to z-axis torque profiles to demonstrate increased or decreased fouling by percent of total fouling. This information can help customers and/or operators to better understand which regions of exchanger 12 are subject to frequent or enhanced fouling and make process adjustments to enhance run times and efficiencies.
In an illustrative embodiment, the assembly and system of the present invention do not utilize scanning device 100. Instead, an operator can utilize motion control computer 120, control console 20, command station 44 and video cameras 30a, 30b, 30c & 30d to identify specific groups of tubes 88 on tube sheet 80 for cleaning. The operator can select these groups of tubes 88 by, for example, identifying specific sections or regions of tube sheet 80 containing these groups of tubes 88. The operator can then navigate the motion of one or more lances 90 to clean these groups of tubes 88.
In an illustrative embodiment, five adjacent lances are utilized such as shown in
Lances 90 can be located within guide tubes 94. Lances 90 can be positioned such that their tip ends 92 align with the open ends 86 of the tubes 88 of exchanger 12. In an illustrative embodiment, the spacing between each lance 90 can be set manually using a bracelet 191 that slips over guide tubes 94 and/or lances 90. Alternately, spacing between lances 90 can be controlled and adjusted by motion control computer 120 without the use of bracelet 191. The size of bracelet 191 can be adjusted to correspond to the distance between the respective tubes 88 on tube sheet 80. When spaced properly, the adjacent lances 90 are preferably able to enter and clean the adjacent tubes 88 of exchanger 12.
During cleaning, assembly 10 can secure lances 90. Assembly 10 can be mounted to exchanger 12 via frame 95 or other mounting means to restrict movement. Alternatively, assembly 10 can be positioned adjacent to exchanger 12 without being mounted thereon, such that cleaning lances 90 and tubes 88 of exchanger 12 are generally on the same horizontal plane and lances 90 can travel in and out of the respective tubes 88 with minimal resistance.
As illustrated in
Control console 20 and command station 44 can be integrated with motion control computer 120. Motion control computer 120 can direct an operator through a series of steps for locating and cleaning tubes 88 of exchanger 12. Each step can be performed via a different screen on touch screen monitor 300 of control console 20. For example, an “exchanger information” screen 301 on touch screen monitor 300 (see
Customer name 302 can be used for cataloging and storing information regarding existing tube patterns for future cleanings. Exchanger ID#303 can be the customer's ID for a particular heat exchanger 12 and can be used for cataloging and retrieval of information regarding the specific exchanger 12 for future cleanings. If the tube pattern of exchanger 12 has been previously defined, it can be retrieved using the exchanger ID#303, thus eliminating the need to describe and define the current tube pattern.
Number of sections 304 can be used to identify the number of sections that a tube sheet 80 will be divided into to accomplish the cleaning of heat exchanger 12. Each section can be defined either manually, iteratively, or using a previously defined grid section, which may then be mirrored either vertically or horizontally (if necessary) to quickly build the next section. Iterative defining can be operator assisted in an illustrative embodiment. Tube spacing 305 can describe, for example, the distance or pitch between the center point of two horizontally adjacent tubes.
Grid style 306 can describe whether the exchanger tube pitch is square or triangular. In a square grid style, tubes 88 on tube sheet 80 may be positioned with the tube spacing equal on a horizontal and vertical plane. For example, if there are four tubes in a square pattern with a tube spacing of 1.25″ then the centers from tube to tube both horizontal and vertical will all equal 1.25″. In a triangular grid style, tubes 88 can be positioned on tube sheet 80 with an equilateral triangular pattern, such that the tube spacing is equal on a horizontal plane, but different on the vertical plane. In this case the system can use a mathematical formula to calculate the proper tube pitch and adjust the movements accordingly.
A “cleaning information” screen 310 on touch screen monitor 300 (see
Tube cleaning speed 312 can indicate the speed in which lance 90 will travel through the bundle. In an illustrative embodiment, there can be two different speeds: a speed moving in, and a speed moving out. The system can be programmed to auto adjust itself to a slower speed if the system encounters obstructions or plugging inside of tube 88. Thresholds can be set on the drive motor to back up and reduce tube cleaning speed before attempting to pass the obstruction. This can loop on pre-programmed intervals until the obstruction is overcome or the system hits a maximum attempt threshold and moves on to the next set of tubes 88.
Lance rotation speed 313 can be measured in revolutions per minute (RPM). The lances 90 can rotate between 0-3000 RPMs in an illustrative embodiment. Rotation direction 314 can indicate the direction in which the lances 90 will rotate. Rotational direction 314 can be set at clockwise or counterclockwise, as desired.
A “section definition” screen 320 on touch screen monitor 300 (see
Initially, the operator can select a section for cleaning 321. This relates back to the number of sections 304 that the operator defined on the “exchanger information” screen 301. The operator may then define how the tubes 88 in that section will be identified. In the event that tube sheet 80 has multiple sections to be cleaned, the operator can define how cleaning will occur for each section.
Section definition can be through a manual process 322, an iterative process 323, or by using a previously defined section as a basis for defining the current section 324.
Manual Process 322
a & 24b are illustrative examples of an edit screen 330 for the manual process 322. Edit screen 330 can display a map that identifies the locations of tubes 88 on open end 86 of exchanger 12. The map of edit screen 330 can display information for two dimensions (x & y), or can be topographical and provide information for three dimensions (x, y & z) in relation to open end 86 of exchanger 12. In certain illustrative embodiments, an operator may utilize, for example, the touch screen functionality of edit screen 330 illustrated in
For example, the operator can utilize edit screen 330 to select grid size from a number of existing options such as, for example, 15×15 or 25×25, or the operator can create a custom grid that corresponds to the pitch of tubes 88, such as square or triangular. The custom grid can correspond to the spatial arrangement of tubes 88 on tube sheet 80. If tube sheet 80 has more tubes 88 than the custom grid can create, that section can be divided into smaller sub-sections for cleaning. The tube centers and pitch can be determined by the information entered on the “exchanger information” screen 301.
The tubes on edit screen 330 can correspond to the tubes 88 on the face of tube sheet 80. The operator can indicate the specific operation that will occur for each tube 88. The tubes on edit screen 330 can be color coded to indicate cleaning functions. In an illustrative embodiment,
Once all relevant tubes have been marked on edit screen 330, the operator can set the home position (NB) tubes, preferably by engaging the “Define Home” button 332 in an illustrative embodiment. In the field, assembly 10 can be positioned with respect to tube sheet 80 such that lances 90 are lined up with the open ends 86 of tubes 88 that correspond to the home position (NB) tubes on edit screen 330. The operator can then engage the “Mark Home” button 333 in an illustrative embodiment. At this point, a start command can be initiated by engaging, for example, the “auto-start” button 351a as shown in the illustrative embodiment of
Iterative Process 323
For example, the iterative process 323 can involve selecting a plurality of points or locations via edit screen 340 that define the outer perimeter of a region of tube sheet 80 to be cleaned. Lances 90 and/or guide tubes 94 can be moved to these various points or locations on tube sheet 80, and the points or locations can be identified by motion control computer 120 as the outer boundary of a “cleaning region”. Motion control computer 120 may then instruct assembly 10 to clean the tubes 88 located at the identified point or locations.
In an illustrative embodiment, the operator can use joystick controller 70 and/or any other required instruments from command station 44, such as the Up/Down/Left/Right buttons 76 as shown in
In an illustrative embodiment of iterative process 323 where five lances 90 are utilized, the operator first selects five adjacent tubes 88 (either horizontal, vertical or diagonal) on edit screen 340 to be considered the home location. This will turn those tubes navy blue (NB) on edit screen 340. Operator can then utilize joystick controller 70 to move lances 90 to the location on tube sheet 80 that corresponds to the home location. A “clean” button 75 (See
The operator can next select a second location on the outer perimeter of the region to be cleaned and identify this location on edit screen 340. The “clean” button 75 can be engaged, and the tubes 88 corresponding to this second location can be cleaned.
The operator can continue to designate the desired cleaning perimeter on tube sheet 80 by selecting additional locations on the perimeter to define a cleaning region and build a computer image of the tube sheet 80. At each location, the “clean” button 75 can be engaged, and the tubes at that particular location can be cleaned.
Identifying the perimeter can involve selecting as few as four locations on tube sheet 80 to create a square region, or as many as twenty-six (or more) locations on a 25×25 grid, assuming one side has a jagged pattern. For example,
Once the operator has defined the outer parameters for the desired region to be cleaned in the iterative process 323, or the entire region to be cleaned in the manual process 322, the operator can engage the “auto start” button 351a of
In an illustrative alternate embodiment, iterative process 323 can involve identifying all the desired points on the perimeter of the region to be cleaned as an initial step. In a subsequent step, the “auto start” button 351a can be engaged to initiate cleaning of all the tubes 88 identified in connection with the initial step. At this time, lances 90 will return to the home location and begin the cleaning process.
Previously Defined Section 324
When defining the section to be cleaned, the operator may mirror a previously defined section 324, either left-to-right or up-to-down, using mirror buttons 800 (see
During the cleaning process, the crosshairs in
In various illustrative embodiments, movement of lances 90 can be performed by an operator in the field or using cleaning-in-progress screen 350, or otherwise via command console 20. Further, in certain illustrative embodiments, automatic control, manipulation and navigation of lances 90 can comprise some level of robotic manipulation of lances 90. Also, a plurality of add/exclude buttons 78 on control panel 20 (see
In the event that assembly 10 and tubes 88 are not on a perfectly horizontal or vertical plane and/or do not line up properly, assembly 10 can tilt up, down, left or right to accurately line up with tubes 88. Assembly 10 can include a motor and lance track tilt ram 701 to ensure that any tilt action stays level throughout the entire cleaning process, as needed. Further, in the event that open end 86 of heat exchanger 12 does not have a flush face (for example, a channel head), assembly 10 may be capable of extending forward and accessing the tube sheet even when a channel head is present. Lance track adjustment ram 700 can extend out to access tubes 88 as needed. An illustrative embodiment of lance track adjustment ram 700 and lance track tilt ram 701 are shown in
A calibration routine can be used to determine the angular dimensions of tubes 88 within tube sheet 80, which can be relevant in determining, for example, if assembly 10 or any of its components will need to be tilted or moved a distance from the horizontal plane in order to access tubes 88. In an illustrative embodiment of the calibration routine, the operator can manually place the lances 90 within tubes 88, at two different points, on the same row of tubes 88 of heat exchanger 12. This can define the angle of tubes 88 within tubesheet 80 with respect to assembly 10, thus determining the necessary tilt angle.
In the event that tube sheet 80 has an irregular cleaning pattern, assembly 10 can be modified to include any desired number of lances. For example, a single lance 90 may be utilized to do follow-up cleaning of any tubes 88 that could not be accessed by a five lance 90 system during initial cleaning.
In an illustrative embodiment, assembly 10 may be located inside of a protective container 600 (not shown). Container 600 may have doors located on both ends. Container 600 can protect assembly 10 from outside elements such as rain, wind and can provide a more stable environment for shipping and relocating.
In an illustrative embodiment as shown in
In an illustrative embodiment, assembly 10 may have a gearbox 199 or other carriage system that can house a plurality of lances 90 on equal centers from lance to lance allowing for rotation of all lances 90 from 0-3000 RPMs. Lances 90 may also be placed in a staggered pattern in gearbox 199 when, for example, tighter patterns are needed. In an illustrative embodiment, all lances 90 can be rotated using a series of pulleys 299 driven by a single belt 399 located within gearbox 199. Alternatively, a series of gears can be utilized to rotate lances 90, or a plurality of belts 399 or motors such as direct drive motors may be utilized, within the present illustrative embodiments.
In an illustrative embodiment, assembly 10 can be utilized to clean a variety of different types of exchangers 12, as well as a variety of types of pipes used in industrial equipment. For example, in certain illustrative embodiments, assembly 10 can be lifted by a crane or other similar lifting device and disassembled and reassembled in the field in order to access exchangers in hard to reach locations. Assembly 12 can be used to clean tubes 88 in a vertically oriented exchanger 12 or otherwise in any vertical orientation, whereby, for example, assembly 10 can be positioned at or near the top end of exchanger 12 such that lances 90 are aligned with tubes 88. Assembly 10 can also be used to clean, for example, fin fan exchangers or the shell side of a shell and tube exchanger. In an illustrative embodiment, assembly 10 and motion control computer 120 can be used to control the cleaning of an outside diameter of a tube bundle. A spray head system can be incorporated with assembly 10 that moves along the shell side of one or more bundles to clean the exterior of the bundles. Assembly 10 can also include a variable speed conveyer 650 (not shown). Items to be cleaned such as industrial piping, scaffolding, column trays or exchanger equipment can be placed on the conveyer 650, and cleaning lance 90 or another cleaning instrument on assembly 10 can be used to clean these pieces of equipment as the equipment is moved by conveyer device 650.
It is to be understood that the invention is not limited to the exact details of construction, operation, exact materials, or illustrative embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. For example, complete automation of assembly 10 is also possible, if desired, through CNC technology. In other words, assembly 10 may operate automatically without the need for a human operator, or alternatively, the assembly 10 may be controlled by a human operator. Also, multiple digital scans of the exchanger tube sheet may be performed at any time during the cleaning process, if necessary. Accordingly, the invention is therefore to be limited only by the scope of the appended claims.
This application claims the benefit, and priority benefit, of U.S. Provisional Patent Application Ser. No. 61/070,073, filed Mar. 20, 2008, titled “Automated Heat Exchanger Tube Cleaning Assembly and System.”
Number | Date | Country | |
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61070073 | Mar 2008 | US |