The assignee for this patent application is
Reporters obtained the following quote from the background information supplied by the inventors: "In chemical or petrochemical plants etc., it is often necessary to convey fluidic materials (e.g. liquids) from one location to another. The conveyance of such material normally includes equipment such as conduits or pipes, storage or reaction vessels etc., which are generally manufactured from metal. The joining of separate pieces of the conveying equipment is generally achieved by welding the necessary pieces together. For example, when joining adjacent ends of pipe together, it is common for each end to be provided with flanges, that are welded to each respective end, which are then bolted together to form a seal. Such flanges may also be provided on holding tanks and other such vessels so that such vessels can be connected to pipes or other vessels. Alternatively, the connections between lengths of pipe or other equipment may be welded directly together (i.e. butt welded) to form the seal. In either case, it will be appreciated that each welded joint or section must form a complete seal so as to prevent leakage of the materials being transported. This is particularly the case when handling potentially hazardous materials such as flammable or toxic liquids.
"For reasons of safety, it is often necessary to periodically test the integrity of the welds used in joining the various pieces of equipment (such as pipes, vessels, flanges and the like) together.
"The prior art provides various tools for conducting weld integrity tests on conduits. For example, U.S. Pat. Nos. 6,131,441 and 5,844,127 (the entire disclosures of which are incorporated herein by reference) teach weld testing tools that isolate a particular section of a pipe (such section including a weld) and subject the section to a high pressure fluid within a constrained annular space defined by the tool and the inner surface of the pipe. The pressure of the fluid within the annular space is monitored whereby any pressure drop signifies a leak in the weld.
"U.S. Pat. No. 6,463,791 (the entire disclosure of which is incorporated herein by reference) teaches an apparatus for testing welds used to secure nozzles. As shown in FIG. 1 of this reference, the apparatus comprises a first seal plate that is placed on the inner surface of the vessel (for example) and a second seal plate that is secured to the outer, flange portion of the nozzle. In this manner, the nozzle volume is sealed and a pressurizing fluid is introduced therein. Once the volume is filled, the pressure is monitored as above and any leakage detected. Although this apparatus provides an accurate and efficient means of testing welds on nozzles, the size and weight of the apparatus makes it inconvenient for use on large nozzles.
"Further, applicant's co-pending U.S. application Ser. No. 11/771,158 (publication number US 2008/0121044), provides tools for testing the integrity of welds on pipes and the like. The entire disclosure of such application is incorporated herein by reference.
"There exists a need for more easily sealing a section of a long pipe for conducting the type of stress tests mentioned above. In addition, there exists a need for an apparatus that is capable of exerting axial stresses on welds during such testing so as to simulate a 'worst case scenario'. In particular, there is a need for an apparatus that can be easily mounted on an open end of a pipe so as to effectively seal the pipe opening and maintain such seal during high pressurization of the pipe. Such apparatus would not subject the pipe to any damage or otherwise cause weakness thereto."
In addition to obtaining background information on this patent application, VerticalNews editors also obtained the inventor's summary information for this patent application: "In one aspect, the present invention generally provides an apparatus for sealing an open end of a pipe comprising: at least one generally annular shaped clamp for being frictionally secured to an outer surface of the pipe, adjacent and spaced from the open end thereof, the at least one clamp including a means for circumferentially gripping the outer surface of the pipe and preventing relative axial movement there-between; a sealing plate, adapted to cover the open end of the pipe, the sealing plate including a means for sealing the open end of the pipe; an urging means for urging the sealing plate axially towards the at least one clamp and against the open end of the pipe.
"In another aspect, the invention provides an apparatus as above and wherein: the at least one clamp is comprised of at least two clamp sections, adapted to be joined together to form an annular body adapted to fit over the exterior surface of the pipe; each of the clamp sections including connecting flanges, provided at opposite ends of the sections, the flanges having a plurality of bolt holes; a plurality of second connecting elements for connecting flanges of adjacent clamp sections and for tightening each clamp section towards adjacent clamp sections for forming said annular shaped clamp.
"In another aspect, the invention provides an apparatus as above and wherein the at least one clamp includes: a generally annular body having an inner diameter surface, at least a portion of the inner diameter surface including a first ramp extending from a first end to a second end of the annular body, the annular body having an inner diameter that is greater at the first end than at the second end; a generally annular gripper ring, coaxial with the annular body, the gripper ring being comprised of two or more sections, and having an inner surface with an inner diameter for engaging the outer surface of the pipe, and an outer surface, at least a portion of the outer surface of the gripper ring including a second ramp, the second ramp extending from a first end of the gripper ring to a second end of the gripper ring, the second ramp being oppositely directed to the first ramp, wherein the second end of the gripper ring is insertable within an annular space between the first end of the annular body and the outer wall of the pipe; and, a means for urging the gripper ring and the main body towards each other for forcing the second ramp under the first ramp, whereby, when the apparatus is in use, the first ramp bears against the second ramp wherein the inner diameter of the gripper ring is reduced resulting in a frictional engagement between the gripper ring and the outer surface of the pipe.
"In another aspect, the invention provides a method for sealing a section of a pipe having an open end, the method comprising: positioning at least one external clamp circumferentially over the outer surface of the pipe at a location spaced away from the open end, the at least one clamp being frictionally secured to the pipe surface so as to prevent relative axial movement between the clamp and the pipe; positioning a sealing plate against the open end of the pipe, for covering the open end, the sealing plate including a groove adapted to receive the open end of the pipe; connecting the sealing plate to at least one of the at least one clamps; forcing the sealing plate axially towards the at least one clamp and forming a seal between the open end of the pipe and the sealing plate.
"In another aspect, the invention provides a method as above and wherein the at least one clamp comprises a generally annular body formed of at least two sections, and wherein the step of securing the external clamp circumferentially over the outer surface of the pipe comprises connecting the at least two sections together and tightening the sections to cause frictional engagement between the at least one clamp and the pipe outer surface.
"In another aspect, the invention provides a method as above and wherein the at least one clamp comprises: a generally annular body having an inner surface, a portion of the inner surface comprising a first ramp; and, a generally annular gripping ring formed of at least two sections, said gripper ring including an outer surface, a portion of the outer surface comprising a second ramp; the method comprising: coaxially positioning the annular body and the gripper ring over a pipe such that the first and second ramps are oppositely oriented, wherein the second ramp of the gripper ring is insertable between the first ramp of the annular body and the outer wall of the pipe; forcing the gripper ring against the annular body to cause radial compression of the gripper ring and frictional engagement of the gripper ring over the pipe outer surface; and, forming a sufficient clamping force between the gripper ring and the pipe surface to prevent relative axial movement between the at least one clamp and the pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
"These and other features of the invention will become more apparent in the following detailed description in which reference is made to the appended drawings wherein:
"FIG. 1 is a cross sectional view of one embodiment of the apparatus of the present invention.
"FIG. 2 is a perspective view of the clamp of the apparatus of FIG. 1.
"FIG. 3 is a cross sectional elevation of another embodiment of the clamp of FIG. 1.
"FIGS. 4, 4b, 5 and 6 are cross sectional views of further embodiments of the present invention.
"FIGS. 7 to 9 are cross sectional views of an embodiment of the invention having an external clamp.
"FIG. 10 is a perspective view of another aspect of the invention shown in FIG. 9.
"FIG. 11 is side view of another aspect of the invention shown in FIG. 10.
"FIG. 12 is an end view of a clamp shown in FIGS. 10 and 11.
"FIG. 13 is a side cross-sectional view of another embodiment of the external clamp according to the invention.
"FIG. 14 is an end view of the embodiment shown in FIG. 13.
"FIG. 15 is a side cross-sectional view of another embodiment of the external clamp according to the invention.
"FIGS. 16 and 17 are front and side cross-sectional views of the squeeze ring shown in FIG. 15.
"FIGS. 18 and 19 are front and side cross-sectional views of the clamping ring shown in FIG. 15.
"FIGS. 20, 21 and 22 are front, side cross-sectional and detailed cross-sectional views of the gripper ring shown in FIG. 15.
"FIG. 23 is a side cross-sectional view of an embodiment of the invention shown in FIG. 15 wherein a plurality of external clamps are combined."
For more information, see this patent application: CARSON, Glenn. Pipe Sealing Tool with External Clamp. Filed
Keywords for this news article include:
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC
Most Popular Stories
- Pandora Tumbles in Late Trading
- Sporty Ford Fiesta Fires on All 3 Cylinders
- Stop-Start Engines Save Gas, Reduce Emissions
- World Tensions Don't Curb Enthusiasm for Stocks
- Russia Fears Lasting Damage From Ukraine Crisis
- Visa, Amazon Results Drag Down the Street
- U.K. Economy Surpasses Pre-Crisis Peak
- Ohio State Band Chief Fired After Probe
- Hispanic Leader Goes the Extra Mile
- Shia LaBeouf Plea Deal, Alcoholism Treatment