The presently disclosed subject matter relates to an inflatable spreading tool for use in the maintenance and/or retrofitting of heat exchangers and other process equipment having bundles of tubing and other elongated members. The methods and systems are particularly applicable to heat exchangers that are provided with Anti-Vibration Technology (AVT) devices.
Anti-Vibration Technology (AVT) exists that can improve the reliability and performance of heat exchangers and other process equipment having at least one bundle of elongated members. Support devices for a bundle of elongated members are disclosed, for example, in U.S. Pat. No. 7,032,655, hereby incorporated by reference in its entirety.
Other AVT devices are disclosed in U.S. Pat. No. 7,267,164, which include a plurality of engaging members extending from a pair of opposing faces, as shown in
The effective thickness of an AVT device, such as dimpled tube support (DTS) strips, may be, at times, a little greater than desired. Tubes may also become slightly distorted over time and block the passage of the strips through the tubelane. Thus, the thickness of the unsupported tube span may vary from one location to another. In any event, substantial flexibility can be provided if the thickness of the unsupported tube span can be made more uniform.
While AVT and other retrofitting devices could be provided with different thicknesses in a given heat exchanger, it would be more desirable to have a single thickness for the AVT device (e.g., DTS strips) to improve efficiency, reliability and ease of placement. Also, if the AVT is too large, it can be damaged during insertion into the bundle owing to the high forces that could be needed to install the device.
Current methods to install AVT devices include, but are not limited to, the use of a mallet to apply force to the AVT device, as well as the use of crowbars to spread the tubes apart when the AVT device is too tight to fit in the tubelane. Manual manipulation is especially needed if an AVT device needs to be removed from the bundle (e.g., incorrect location or because the tubelane is partially blocked by distorted tubes). This process could take up to 15 minutes per AVT device, and there is a desire to reduce maintenance time in order to decrease plant downtime. A more efficient approach is desired, preferably one that also reduces the likelihood of damage to the tubes.
While improved heat exchanger operation can be provided by retrofitting various internal devices, such as AVT devices, including but not limited to, those disclosed above, into process equipment having at least one bundle of elongated members, there is a general need to decrease down time due to the implementation of these design improvements. For example, there is a desire to make the installation, maintenance and retrofitting of AVT devices easier and less time consuming.
According to one aspect of the present application, a method of performing an operation on a process equipment having at least one bundle of elongated members is provided. The method includes providing an inflatable spreading tool in a deflated condition, inserting the inflatable spreading tool between at least two adjacent elongated members, the adjacent elongated members being spaced an initial distance from each other, and inflating the inflatable spreading tool to increase the distance between the adjacent elongated members.
According to another aspect of the present application, a system for use in an operation on a process equipment having at least one bundle of elongated members is provided. The system includes an inflatable spreading tool including a tubular member having a proximal end and a distal end, the tubular member having a deflated state and an inflated state. The tubular member is sized to fit between at least two adjacent elongated members when deflated, the two adjacent elongated members being spaced an initial distance from each other. The inflatable spreading tool further includes a coupling for fluid communication with a pressurizing source to inflate the tubular member to the inflated state, the tubular member capable of increasing the distance between the adjacent elongated members when the tubular member is in the inflated state.
Reference will now be made in detail to the various aspects of the presently disclosed subject matter. The systems of the disclosed subject matter will be described in conjunction with, and understood from, the detailed description of the methods.
According to one aspect of the present application, a method of performing an operation on a process equipment having at least one bundle of elongated members is provided. The method includes providing an inflatable spreading tool in a deflated condition, inserting the inflatable spreading tool between at least two adjacent elongated members, the adjacent elongated members being spaced an initial distance from each other; and inflating the inflatable spreading tool to increase the distance between the adjacent elongated members.
In one embodiment, the method further includes inserting a device between the adjacent elongated members, and subsequently deflating the inflatable spreading tool. The device can be an anti-vibration technology (AVT) device. According to one embodiment, the process equipment is a heat exchanger and the elongated members are tubes.
The inflatable spreading tool can include a flat tubular member, such as a flat hose or a flat metallic tube. The inflatable spreading tool can be inflated with a gas, such as air, or alternatively, the inflatable spreading tool can be inflated with a liquid such as an oil or water. The inflatable spreading tool can include a rigid strip to facilitate insertion between two adjacent elongated members. The rigid strip can be connected to the tubular member. Alternatively, a distal end of the inflatable spreading tool can be welded to form a closed end.
According to another aspect of the present application, a system for use in an operation on a process equipment having at least one bundle of elongated members is provided. The system includes an inflatable spreading tool including a tubular member having a proximal end and a distal end, the tubular member having a deflated state and an inflated state. The tubular member is sized to fit between at least two adjacent elongated members when deflated, the two adjacent elongated members being spaced an initial distance from each other. The inflatable spreading tool further includes a coupling for fluid communication with a pressurizing source to inflate the tubular member to the inflated state, the tubular member capable of increasing the distance between the adjacent elongated members when the tubular member is in the inflated state.
The presently disclosed subject matter provides a simple, inexpensive and very effective tool to spread apart tubes or other elongated members to provide easy placement of, for example, AVT devices in the desired locations within process equipment having bundles of tubing and other elongated members. The presently disclosed device can be placed in the same tubelane as, and adjacent to, the intended AVT device location. Once in position, the inflatable spreading tool is pressurized to create an adequate space for placement of the AVT device in the desired location. Then the inflatable spreading tool is deflated and removed from the tube bundle with, for example, the AVT device in position. The presently disclosed inflatable spreading tool can improve the robustness and acceptability of devices to, internally applied to, for example, heat exchangers.
The described invention provides substantial benefits, including (a) faster installation (especially, when the AVT device thickness is greater than ideal and/or when some tubes are distorted), (b) safer and faster removal of AVT devices, and (c) reduced risk of damage to AVT devices.
For purpose of illustration and not limitation,
As shown in
In some situations, it can be desirable to insert the inflatable spreading tool without access from the other side of the bundle. This is especially the case for AVT devices used within the U-bend region as it is desirable for the inflatable spreading tool to be positioned parallel to the major axis of the tube bundle within the U-bend region. As shown in
In this case, as shown in
It is also possible and, perhaps, preferable for safety reasons to use a liquid or fluid to pressurize the flat-hose system. This fluid can be, for example an oil, water or other liquid. In this case, it would be necessary to drive the fluid back from the hose to a small reservoir when the hose needs to be deflated.
During fabrication of the flat metallic tube, a metallic rod (not shown) can be inserted when forming each edge (230) of the flat tube, as shown in
The present invention is not to be limited in scope by the specific embodiments described herein. Indeed, various modifications of the invention in addition to those described herein will become apparent to those skilled in the art from the foregoing description and the accompanying figures. Such modifications are intended to fall within the scope of the appended claims.
It is further to be understood that all values are approximate, and are provided for description.
Patents, patent applications, publications, product descriptions, and protocols are cited throughout this application, the disclosures of each of which is incorporated herein by reference in its entirety for all purposes.
This application relates and claims priority to U.S. Provisional Patent Application No. 61/422,381, filed on Dec. 13, 2010 and U.S. Provisional Patent Application No. 61/432,064, filed on Jan. 12, 2011.
Number | Date | Country | |
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61432064 | Jan 2011 | US | |
61422381 | Dec 2010 | US |