1. Field of the Disclosure
This disclosure generally relates to systems and methods for cutting a workpiece. More particularly, the disclosure relates to a hot tap process for cutting an opening in a pipe, and retaining the cut portion after cutting the opening.
2. Background of the Disclosure
In the modern world it is axiomatic as to the extensive necessity for pipes or pipelines that are used to supply fluids both for residential and industrial purposes. These fluids may be liquid or gas, with common examples being water and natural gas. The pipe and fluid may be pressurized.
On occasion it becomes necessary to change the pipe network or configuration in some manner, which may be dictated by increased demand (and hence increased flow) or environmental factors. The need thus follows to add a new service tap on to a segment of the pipe, which may be safely done by removing any process fluid from the pipe and/or and disconnecting the applicable pipe segment from the network. However, in some instances it is inconvenient to shut down the process flow running through the pipe during such an operation, as doing so would cut off service to those connected with that particular part of the pipe network. In the production sense, stopping production is unfavorable because of the expense and loss of production incurred.
Accordingly, it is well known in the art to undertake a “hot tap” procedure, which essentially provides for maintaining some amount of process flow while cutting through (and removing) a portion of the pipe resulting in an opening therein. The process of hot tapping into a “live” pipe is an unsafe event that requires operational skill and machine safety to prevent the release of the process flow to the atmosphere, fire, or explosion. Once the hot tap is completed, a new process line or branch can be connected to the pipe, and the requisite change in flow can occur therethrough.
The hot tap machine 106 is connected (e.g., bolted or other suitable form of attachment) to the valve 104, where the components are configured in a manner that allows a shaft 108 and cutter (e.g., hole saw) 110 to fit through the valve 104 and the saddle 102 in order to make cutting contact with an outer surface 114 of the pipe 100. Although not shown here, the hot tap machine 106 is often powered by a rotational motor that can be electric, pneumatic, hydraulic, etc., as well as a mechanism analogous to a drill press (such as a lever or spindle). The motor provides rotary capability to the shaft 108, while the mechanism provides for axial movement (e.g., up and down) for the shaft 108.
Attached to an end 105 of the shaft 108 is the cutter 110. The cutter is typically a hole saw, and the end 105 is also typically configured with a pilot bit 112, which is used to provide alignment and make the initial penetration into the pipe 100 during the cutting process.
Once all requisite equipment is in place and tested for integrity, the hot tap process starts with the cutter 110 and bit 112 rotated at a given speed and driven down by aforementioned means to come into contact with the pipe 100. As the pilot bit 112 drills through the pipe 100, the cutter 110 moves into contact with the pipe 100 and eventually cuts a portion of pipe 116 (conventionally the “coupon” or plug) out of the pipe 100.
Unfortunately in addition to the danger factors associated with cutting a pipe while process flows therethrough (e.g., explosion or fire) is the major risk of losing the coupon 116. Loss of the coupon 116 into the process flow is significantly problematic because it easily and freely can enter downstream equipment and has the potential to cause catastrophic or costly, major damage to the plant process. This may result in complete shut down or significant flow reduction. Sometimes this may be mitigated by flow reduction prior to starting the hot tap process. The flow rate reduction is achieved by reducing throughput or capacity of the plant process. Ultimately then the true cost of a hot tap is a combination of the operational cost of the hot tap process itself, in addition to any loss of production for the term of the hot tap process.
The coupon 116 may be unretained for several reasons, such as too great of size or weight for the hot tap machine to retain, or mechanical failure or inability. More to the point the prior art has not provided a satisfactory or viable solution to the problem of coupon retention. One crude solution entails the pilot bit 112 fitted with a spring, clip, wire, or other form of bit piece 103 that is intended to retain the coupon 116 once it has been cut out from the pipe 100. However, in actual operation such devices are wholly inadequate and prone to routine failure.
Thus, there is a tremendous need in the art for methods and systems of cutting a pipe that provide for improved coupon retention.
Embodiments of the disclosure pertain to a method for cutting a workpiece that may include the steps of positioning a first element proximate to an outer surface of the workpiece; operatively associating the first element with a cutting machine; operating the cutting machine to cutout a portion of the workpiece in an area where the first element is positioned; and removing the portion of the workpiece while the portion is in connection or mechanical communication with at least one of the first element and the cutting machine.
The method may include fixedly connecting a second element to the other surface of the workpiece. The positioning the first element step may include coupling the first element and second element together. The workpiece may be selected from a group of items such as a pipe or a vessel. In aspects, fixedly connecting may include welding. The first element may be a cylindrical elongate member configured with at least one groove. The groove(s) may be configured for receiving one of an o-ring and a bias member. The second element may be a stud. In aspects, the stud may be a welded stud. In other aspects, the stud may be a threaded stud.
The cutting machine may be configured with a vacuum system. The portion of the workpiece may be or include a coupon. In aspects, the coupon may have a mass in the range of about 0.1 lbs to about 10 lbs. The method may include operating the vacuum system to pull a vacuum on the first element in the range of about 0.1 inches mercury to about 25 inches mercury.
The positioning the first element step may include fixedly connecting the first element to the outer surface of the workpiece. Operatively associating the first element with a cutting machine may further include centralizing alignment of the cutting machine with the first element. In aspects, the method may include disposing a coupler on the workpiece; connecting a valve to the coupler; and engaging the cutting machine with the valve. A process fluid may flow through the workpiece while performing the method.
Operating the cutting machine may include rotating a hole saw. The first element may be stationary while the hole saw rotates during cutting. In aspects, no hole is drilled or otherwise cut in the portion.
Other embodiments of the disclosure pertain to a system for cutting a workpiece that may include a motor configured to work a shaft; a cutter operatively connected to the drive shaft; and a second member configured for engagement to the workpiece, and for coupling the first element with the workpiece. The shaft may be configured to engage a first member. In aspects, during cutting the drive shaft and cutter may be movable, and the first member and second member may be stationary.
The system may include a cutting machine. The motor, shaft, and cutter may be part of the cutting machine. The system may be configured to for removal of a portion of the workpiece while the portion is in connection with at least one of the first element and the cutting machine. The system may further include a retainer mechanism.
The workpiece may be a pipe or a vessel. In aspects, the workpiece is a pipe.
The retainer system may be operable to provide a vacuum pulled on the first member in the range of about 0.1″ to about 25″.
Either one of the shaft or the first member may include one or more bias members.
The system may further include a coupling device disposed on the workpiece; a valve connected to the coupling device; a cutting machine attached to the valve.
In aspects, the cutting machine may be configured to rotate the shaft and the cutter. During system operation the first element may be stationary while the cutter rotates.
Yet other embodiments of the disclosure pertain to a hot tap system for cutting out a portion of a pipe that may include a coupling device connected to the pipe; a first member also connected to the pipe; and a hot tap machine coupled with the coupling device. The hot tap machine may include a shaft and a cutter. The shaft may be configured to align with and engage the first member. One of the hot tap machine, the first member, and combinations thereof may be configured with a retaining mechanism that provides retention on the portion of the pipe during cutting.
The hot tap machine may include a motor configured to rotate the shaft and cutter. In aspects, the portion of the pipe may be a coupon. The retainer mechanism may include one or more a bias members. One or more bias members may be disposed within the first member.
Yet other embodiments of the disclosure pertain to a method for cutting a pipe that may include positioning a first element proximate to an outer surface of the pipe; operatively associating the first element with a hot tap machine; operating the hot tap machine to cutout a coupon from the pipe in an area where the first element is positioned; and removing the coupon while the coupon is in connection with at least one of the first element and the cutting machine.
The method may include fixedly connecting a second member to the outer surface of the pipe. The method may also include coupling the first member to the second member. Fixedly connecting may include welding. The first element may be a cylindrical elongate member. The second element may include a stud.
The shaft may include a bias member. The first member may include a groove configured to receive the bias member. The first member may include at least one bias member. The may include a respective groove(s) configured to receive the at least one bias member.
The method may include disposing a saddle on the pipe; connecting a valve to the saddle; engaging the cutting machine with the valve. A process fluid may flow through the pipe while performing the method. Operating the cutting machine may rotate a hole saw, wherein the first element is stationary while the hole saw rotates during cutting, and wherein no hole is drilled in the coupon.
These and other embodiments, features and advantages will be apparent in the following detailed description and drawings.
A full understanding of embodiments disclosed herein is obtained from the detailed description of the disclosure presented herein below, and the accompanying drawings, which are given by way of illustration only and are not intended to be limitative of the present embodiments, and wherein:
Embodiments of the present disclosure are described in detail with reference to the accompanying Figures. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, such as to mean, for example, “including, but not limited to . . . ”. While the disclosure may be described with reference to relevant apparatuses, systems, and methods, it should be understood that the disclosure is not limited to the specific embodiments shown or described. Rather, one skilled in the art will appreciate that a variety of configurations may be implemented in accordance with embodiments herein.
Although not necessary, like elements in the various figures may be denoted by like reference numerals for consistency and ease of understanding. Numerous specific details are set forth in order to provide a more thorough understanding of the disclosure; however, it will be apparent to one of ordinary skill in the art that the embodiments disclosed herein may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description. Directional terms, such as “above,” “below,” “upper,” “lower,” “front,” “back,” etc., are used for convenience and to refer to general direction and/or orientation, and are only intended for illustrative purposes only, and not to limit the disclosure.
Although embodiments of the disclosure may reference a ‘pipe’, the disclosure is not limited, as embodiments may be suitable for other components, such as ducting, plastic tubing, non-pipe structures, atmospheric or pressure vessels, and the like. In that sense embodiments of the disclosure are applicable to any process where a cut or a cut opening in a workpiece is required or desired. A workpiece may be a structure that requires a cut or cutout, such as to form an opening. In a similar manner although the description may refer to a ‘hot tap’, embodiments of the disclosure are not meant to be limited as there is applicability to ‘cold tap’ or other cutting processes that result in a cut or cutout. Connection(s), couplings, or other forms of contact between parts and so forth may include conventional items, such as lubricant therebetween, additional sealing materials, such as a gasket between flanges, PTFE between threads, and the like. Embodiments of the disclosure provide for one or more components to be new, used, and/or retrofitted to existing machines and systems.
Referring now to
As shown in
The first member 207 may be used for alignment of a coupling device 202 attachment to the workpiece 200. The first member 207 may also provide longitudinal and latitudinal alignment for a machine shaft 208 (or machine 206). In this respect, the machine shaft 208 may be hollowed, at least partially, in order to fit down on and around the first member 207. The first member 207 may be a lone integral component, or it may be used in combination or connection with other pieces, such as a second member (not shown here). The first member 207 may be attached to the workpiece by known methods, such as threaded (e.g., threaded into the wall of the pipe without breaking into the pressurized interior of the pipe), welded, friction welded, electroweld, and the like. In embodiments the first member 207 is non-rotating while the shaft 208 rotates during operation of system 220. Accordingly, the shaft 208 may rotate around the stationary and fixed first member 207.
The coupling device 202, such as a tapping saddle or saddle valve (or just “saddle”), may fitted or secured to the workpiece 200. The coupling device 202 may be fitted with a flange or flange connection 201, other conventional form of mating attachment device (e.g., threads, etc.). A suitable coupling saddle structure is taught by U.S. Pat. No. 5,893,686, the entire disclosure of which is incorporated herein for all purposes. An example of a commercial coupling saddle suitable for embodiments herein is sold by the Ford Meter Box Company, Inc.
There may be an intermediate valve 204, which may be configured to control or contain process flow while penetration is made into the workpiece 200. The valve 204, such as a gate or ball valve, may be mated with the coupling device 202 via connection 201. Although not shown here, the coupling device 202 may include a valve configuration whereby use of intermediate valve 204 is unnecessary. For example, for a cold tap or non-pressurized cut (e.g., in non-hazardous environments).
The process to cut the workpiece 200 with system 220 may include turning (or positioning, operating, adjusting, etc.) the valve 204 to an open position 211 or a closed position (not shown here). As would be apparent to one of skill in the art, the closed position of a valve includes where flow is completely or substantially blocked from exiting or passing through the valve, and the open position (including partial open position) of the valve is essentially any non-closed position. The valve 204 may be moved to a suitable enough open position, whereby components of cutting machine 206 may pass therethrough. As such, in the open position 211 the shaft 208 and cutter 210 may be lowered therethrough (including onto and around first member 207), and ultimately into contact with an outer surface 214 of the workpiece 200. In embodiments, the cutter 210 may be a hole saw. In an embodiment, system 220 may be used in a hot tap operation. In embodiments, the workpiece 200 may be a pipe. Thus, the cutting machine 206 may be a ‘hot tap’ machine (such as for cutting a pipe); however, embodiments herein are not meant to be limited and other machines configured for cutting are within the scope of the disclosure. As shown, the cutting machine 206, and hence shaft 208, may be positioned approximately perpendicular to the workpiece 200 to enable ease of cutting.
The cutting machine 206 may be coupled with the valve 204. The shaft 208 may be passed (e.g., lowered) though the flange connection 201 between the machine 206 and valve 204. The system 220 and/or cutting machine 206 may include a retainer mechanism (designated as box 260 for illustration). “Mechanism” in this context may be a single device, a force, or combination of devices, moving parts, systems, subsystems, components, subcomponents, forces, and the like. In other embodiments, the first member 207 may include the retainer mechanism 260. In yet other embodiments, the proximity or engagement of the cutting machine (or components thereof) 206 with the first member 207 may form or otherwise result in the operability of the retainer mechanism 260.
The retainer mechanism 260 provides the ability to maintain a retention force or capability on the workpiece portion (or soon-to-be formed workpiece portion) (see 616,
Once the cutter 210 penetrates and cuts the workpiece 200 in the desired manner, typically until cut out of the workpiece portion (616) is complete, it may be withdrawn back through device 202, valve 204, etc. and into machine housing 226. The valve 204 may be moved to the closed position, and the machine 206 removed therefrom (usually after ensuring any process fluid is cleared first).
Referring now to
As shown in
The first member 307 may be a lone integral component, or it may be used in combination or connection with other pieces, such as a second member 309. The first member 307 may be attached directly or indirectly to the workpiece 300 by known methods, such as threaded, welded, friction, welded, electroweld, and the like.
The second member 309 may be used for alignment base to center of the coupling device 302 attachment to the workpiece 300. This may also provide longitudinal and/or latitudinal alignment for the machine shaft 308. The second member 309 may be a stud, welded stud, threaded stud, etc. The second member 309 may be attached by known methods, such as threaded, welded, friction, welded, electroweld, and the like.
Referring briefly to
Referring again to
The coupling device 302 (such as a “saddle”) may fitted or secured to the workpiece 300. The coupling device 302 may be fitted with a flange or flange connection 301, other conventional form of mating attachment device (e.g., threads, etc.). There may be an intermediate valve 304, such as a gate or ball valve, mated with the coupling device 302 via connection 301. Although not shown here, the coupling device 302 may include a valve configuration whereby use of intermediate valve 304 is unnecessary.
A cutting machine 306 (which may include housing 326) may be coupled with the valve 304. In embodiments, the cutting machine 306 may be a hot tap machine. The cutting machine 306 may be conventionally powered, such as pneumatically, hydraulically, electrically. In embodiments the cutting machine 306 may be powered in a manner providing safe use in otherwise flammable or hazardous environments. In embodiments, the cutting machine 306 may be manually powered, such as by crank. The machine 306 may be configured to accommodate interchangeable shafts, which may provide for the ability for insertion of a variety of shaft lengths and types (e.g., cutting thread tip, point tip, auger tip) to correspond to an array of workpiece physical restrictions and materials.
The shaft 308 may be passed though the flange connection 301 between the machine 306 and valve 304. System 320 and/or the cutting machine 306 may include a retainer mechanism 360. “Mechanism” in this context may be a single device, a force, or combination of devices, moving parts, systems, subsystems, components, subcomponents, forces, and the like. In other embodiments, the first member 307 may include the retainer mechanism 360. In yet other embodiments, the proximity or engagement of the cutting machine (or components thereof) 306 with the first member 307 may form or otherwise result in the operability of the retainer mechanism 360.
The retainer mechanism 360 provides the ability to maintain a retention force on the workpiece portion (or where the workpiece is being cut) (see 616,
Referring briefly to
The sealing element 730 may sealingly engage or press the inner surface 715 of shaft 708. The sealing engagement may ensure fluids do not inadvertently pass into the cutting machine (e.g., 306,
Referring briefly to
The first member 807 may be configured with one or more bias members 850. As just one example, the first member 807 may be machined with a respective groove or notch 853, and the bias member 850 may be disposed (such as a fixed connection like a weld, threading, etc.) or otherwise fitted (such as press fit) in the groove 853. By way of example, the bias member 850 may be a spring plunger (see
The shaft 808 may be hollow at least partially or through an extended length of the shaft 8080. The shaft 808 may be configured with a shaft groove 851. Accordingly, the shaft 808 cutting position (e.g., the cutter 810 engaged with workpiece 800) may coincide with the bias member 850 engaged with the groove 851. The engagement of the bias member 850 with the groove 851 may result in a partial energized (or de-energized) position 866 of the bias member 850 (e.g., partial compression of spring segment 865). There may be a plurality of grooves 851 and respective members 850.
Optionally, the shaft 808 may be sealingly engaged with the first member 807. In embodiments, the shaft 808 may be rotatingly engaged with the first member 807. As such, during cutting the shaft 808 may freely rotate, whereby cutter 810 cuts workpiece 800, while first member 807 remains fixed and stationary.
As
Referring briefly to
The pump 942 may be connected (such as fluidly connected) with housing nozzle or port 945. Operation of the pump 942 may result in a vacuum (or pulling) pressure on an area 948 of the first member 907. Any resultant vacuum may be released by opening a vent or bleed valve (not shown) associated with the cutting machine 906 or vacuum system 946.
The pump 942 may be configured and otherwise operably connected with the cutting machine 906 to secure and retain the first member 907) within the shaft 908, and resultant workpiece portion connected therewith. The shaft 908 may be re-positionable and otherwise movingly engaged with the first member 907. Movement of the shaft 908 may be by manual or automatic operation, and may be as a result of mechanical, hydraulic, pneumatic, and the like pressure (or force). Downward movement ultimately results in the engagement of cutter 910 with workpiece 900.
Referring again to
During cutting, the shaft 308 may be moved axially toward the workpiece 300, whereby the cutter 310 may then engage and cut the workpiece 300. Sufficient pressure may be applied automatically or manually. The 310 may be a hole saw; however, embodiments of the disclosure are not limited to any particular cutter type. Instead, the cutter may be any component adaptable for cutting through a surface of a workpiece. Moreover, although the type of cut for a hot tap process is typically round or circular (e.g., a hole), embodiments of the disclosure are not limited to any particular type or shape of cutout. The workpiece portion (e.g., 616,
Upon sufficient completion of cutting, the workpiece portion may be removed by way of reverse axial movement of shaft 308 (as a result of retention mechanism 360 maintaining connection therewith). The cutting machine 306 may be decoupled and a branch pipe (not shown) attached in its place. The valve 304 may then be opened to fluidly connect the branch without altering pressure in pipe 300.
The cutting element 310 may rotate about the mutual rotational axis with the shaft 308 at a radius corresponding to the desired pipe opening diameter. The cutting element 310 may have an adjustable radial position, which may be moved or otherwise adjusted such that the same cutting element 310 may be used to cut wide range of circular opening diameters. The cutting element 310 or its members may be interchangeable to allow replacement of worn bits or substitution of alternative cutting bits for varying workpiece materials and configurations.
Referring briefly to
Advantages.
Embodiments beneficially remove the need for use or requirement of a pilot drill bit. No flow rate reduction during the cutting process is required because the coupon is completely retained. Improved downstream reliability and safety after hot tap process.
With the coupon mechanically attached to the shaft of the hot tap machine, the risk of a lost coupon may be substantially reduced or removed altogether, greatly improving the hot tap process.
With the fixed, primary, center shaft, the coupon is mechanically coupled to the machine shaft and resultantly stay within the cutter. This prevents the coupon from coming into the flow turbulence of the process as well as prevents the coupon from spinning and detaching from the shaft. The travel of the outer shaft or housing can be designed to only travel a given distance, to provide the added safety factor of preventing the hole saw from cutting all the way through the pipe on both sides.
While embodiments of the disclosure have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit and teachings of the disclosure. The embodiments described herein are exemplary only, and are not intended to be limiting. Many variations and modifications of the disclosure presented herein are possible and are within the scope of the disclosure. Where numerical ranges or limitations are expressly stated, such express ranges or limitations should be understood to include iterative ranges or limitations of like magnitude falling within the expressly stated ranges or limitations. The use of the term “optionally” with respect to any element of a claim is intended to mean that the subject element is required, or alternatively, is not required. Both alternatives are intended to be within the scope of any claim. Use of broader terms such as comprises, includes, having, etc. should be understood to provide support for narrower terms such as consisting of, consisting essentially of, comprised substantially of, and the like.
Accordingly, the scope of protection is not limited by the description set out above but is only limited by the claims which follow, that scope including all equivalents of the subject matter of the claims. Each and every claim is incorporated into the specification as an embodiment of the present invention. Thus, the claims are a further description and are an addition to the preferred embodiments of the present invention. The inclusion or discussion of a reference is not an admission that it is prior art to the present invention, especially any reference that may have a publication date after the priority date of this application. The disclosures of all patents, patent applications, and publications cited herein are hereby incorporated by reference, to the extent they provide background knowledge; or exemplary, procedural or other details supplementary to those set forth herein.
Filing Document | Filing Date | Country | Kind |
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PCT/US2014/043030 | 6/18/2014 | WO | 00 |
Number | Date | Country | |
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61842039 | Jul 2013 | US |