Gate Insert Valve and Method of Insertion into a Pressurized Pipeline

Abstract

A method of installing a replacement gate valve in a pipeline in a fully pressurized state by cutting and removing a part of a pipe such as a prestressed concrete cylinder pipe and using a replacement valve body. The replacement valve body includes two cylinders that match the openings of the cut pipe, and inside each of the two cylinders, there is a cutting covering assembly including a cylindrical elastomer seal and a spring tube. The replacement valve body further includes a linear movement gate at the central portion of the valve. When the cylinder end of the replacement valve body is positioned adjacent to the hole of the cut pipe end, the gate is moved to push each elastomer seal of the cutting covering assembly into the hole of the cut pipe end, thereby covering the gap formed when the pipe is cut and engaging the pipe end with the replacement valve body in a fluid-tight manner.

Description

Technical Field

[0001] Previously, the ends of pipe insert valves were joined by bells and plugs that were much larger and more complex than the diameter of the pipe to perform the joining, and these configurations had to slide mechanically together within a pressurized housing. In prestressed concrete cylinder pipe (PCCP), only a short working area is allowed because the thin cylinder can remain constrained. According to the known sealing method of external pipelines, wires need to be stripped from a long area of the cylinder, there is a risk of rupture or cylinder breakage, and the insertion of the valve is hindered. Therefore, there is still a need for an improved method of installing valves in PCCP, especially in systems that do not use butterfly valves, such as untreated sewage systems.

Summary of the Invention

[0002] This method and replacement valve enable the installation of a gate valve by requiring a temporary housing to be installed only in a short area, and when the housing is removed, an external coupling can be installed at the same location of the procedure. This procedure is feasible with most known pipe types, including a special pipe called prestressed concrete cylinder pipe.

[0003] In particular, this replacement valve assembly: (1) A valve body having a right side and a left side, the valve body including a right cylinder, a left cylinder, and a central chamber between the right cylinder and the left cylinder, the central chamber, the right cylinder, and the left cylinder being arranged along a longitudinal axis and being in fluid communication to form a fluid passage between a right cylindrical opening of the right cylinder and a left cylindrical opening of the left cylinder, the central chamber comprising a valve body with a movable valve that may be a gate valve; (2) A right cut covering assembly inside the right cylinder; A right tube, optionally a spring tube, having an outer surface, an inner surface, a right side and a left side, A right elastomeric seal having an outer surface and an inner surface, wherein the outer surface of the right elastomeric seal contacts the inner surface of the right cylinder, and the inner surface of the right elastomeric seal contacts the outer surface of the right tube, the right elastomeric seal, A right inclined surface formed on or mechanically connected to the left side of the right tube, the inclined surface having an angle less than 90° and extending into the central chamber, the right inclined surface, including a right cut covering assembly, (3) A left cut covering assembly inside the left cylinder, A left tube, optionally a spring tube, having an outer surface, an inner surface, a right side and a left side, A left elastomeric seal having an outer surface and an inner surface, wherein the outer surface of the left elastomeric seal contacts the inner surface of the left cylinder, and the inner surface of the left elastomeric seal contacts the outer surface of the left tube, the left elastomeric seal, A left inclined surface formed on or mechanically connected to the right side of the left tube, the inclined surface having an angle less than 90° and extending into the central chamber, the left inclined surface, including a left cut covering assembly,

[0004] When the valve of the valve assembly moves between a first position and a second position, for example, from the upper part to the lower part of the valve assembly, the right side of the valve contacts the inclined surface of the right tube, and the right end of the right cut covering assembly is pushed out from the right cylindrical opening, and at the same time, the left side of the valve contacts the inclined surface of the left tube, and the left end of the left cut covering assembly is pushed out from the left cylindrical opening. By this operation, the valve assembly is fluid-tightly engaged with the cut end of the pipe fixed therebetween.

[0005] In one embodiment, the inclined surface is formed by the ends of the right tube and the left tube. Specifically, the right inclined surface is formed on the left side of the right tube, and the left inclined surface is formed on the right side of the left tube. In another embodiment, the inclined surface is mechanically connected to a cross brace fixed within the right tube and the left tube. In this embodiment, at least a first cross brace extends between a first position on the inner surface of the right tube and a second position on the inner surface of the right tube, and the right inclined surface comprises a flange extending inwardly from the first cross brace towards the central chamber. At least a second cross brace extends between a first position on the inner surface of the left tube and a second position on the inner surface of the left tube, and the left inclined surface comprises a flange extending inwardly from the second cross brace towards the central chamber. Preferably, each of the flanges of the first cross brace and the second cross brace is a bent bar or a curved bar. In other embodiments, a third cross brace extending between the inner surfaces of the right tube may be added, and the third cross brace comprises a flange having an inclined surface extending inwardly from the third cross brace towards the central chamber. Also, a fourth cross brace extending between the inner surfaces of the left tube may be added, and the fourth cross brace comprises a flange having an inclined surface extending inwardly from the fourth cross brace towards the central chamber.

[0006] This valve assembly can be used, for example, in a method of replacing a valve within a pipe. The method comprises: engaging a housing fluid-tightly with the pipes on the right and left sides of the valve; cutting the pipes on the right and left sides of the valve, thereby creating a right opening and a left opening in the pipes; removing the valve through the housing; Advancing a replacement valve assembly within the housing, wherein a cutting cover assembly is disposed within each pipe end of the replacement valve assembly, each cutting cover assembly including a cylindrical elastomeric seal, a tube within the seal, and an inclined surface formed within the tube or mechanically connected to the tube, the inclined surface having an angle of less than 90° and extending inwardly toward a central portion of the valve assembly, the valve assembly further including a linear movement valve for placement between the cutting cover assemblies; Aligning the pipe ends of the valve assembly with the right and left openings of the pipe; Moving the valve from a first position to a second position such that the right side of the valve contacts the inclined surface of the right cutting cover assembly and the right end of the right cutting cover assembly is pushed into the right opening of the pipe, and simultaneously the left side of the valve contacts the inclined surface of the left cutting cover assembly and the left end of the left cutting cover assembly is pushed into the left opening of the pipe, thereby fluid-tightly engaging the valve assembly with the cut ends of the pipe.

[0007] In one embodiment, the inclined surface of the right cutting cover assembly is formed on the left side of the tube of the right cutting cover assembly, and the left inclined surface is formed on the right side of the tube of the left cutting cover assembly. Alternatively, the inclined surface may have the shape of a flange extending from a first cross brace within the tube of the right cutting cover assembly and another flange extending from a second cross brace within the tube of the left cutting cover assembly.

[0008] The pipe in which the valve is installed according to an embodiment of this method is a prestressed concrete cylinder pipe (PCCP), and has a concrete outer layer, an internal metal cylinder, and wires wound around the metal cylinder. In this embodiment, it is preferable that the method further includes the step of adding a centering collar that matches the outer diameter of the pipe to each of the upper portions of the right opening and the left opening of the pipe.

Brief Description of the Drawings

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Description of Reference Signs

[0010] The reference signs in the figures refer to the following: Component Part Reference Sign Tension Wire 1 Outer Restraint Clamp 2 Left Restraint Clamp 211 Right Restraint Clamp 212 Central Restraint Clamp 3 Bolt (with nut) 4 Concrete Coating 5 Mounting Flange 6 Cylinder 7 Pressurizing Housing / Housing 9 Lower Part of Pressurizing Housing 9A Upper Part of Pressurizing Housing 9B Service Valve 10 Machine Ground 11 Wheel 12 Abrasive Belt 13 Stabilizing Member 15 Screw Jack 17 Internal Support Bracket of Housing 19 Pipe Section 20 Valve Binding Pipe Section 20A End Assembly of New Pipe 21 Body of New Valve 22 Right Side of Valve Body 221 Left Side of Valve Body 222 Right cylinder 223 of valve body Inner side of right cylinder 2231 Opening of right cylinder 224 Left cylinder 225 of valve body Inner side of left cylinder 2251 Opening of left cylinder 226 Central chamber 227 Fluid passage 228 Actuating nut 23 First inner edge 241 Second inner edge 242 Seal 26 Outer side of seal 261 Inner side of seal 262 Inner split spring tube 25 Overlapping spring tube 25A Outer side of tube 251 Inner side of tube 252 Tube 255 Right tube 256 Left tube 257 Cross brace 27 First cross brace 271 Second cross brace 272 Inner flange of cross brace 275 Upper end of inner flange 276 Lower end of inner flange 277 O.D. centering collar (outer diameter) 28 Mounting surface 28A Gate (isolator) valve 29 Right side of gate valve 291 Left side of gate valve 292 Proximal end of gate valve 293 Distal end of gate valve 294 Cutting tool 30 Wet tapping tool 31 Tapping tool hole saw 33 Bonnet 32 Pipe (pipeline) 35 Left side of pipe 351 Right side of pipe 352 Left inner part 353 of the pipe Right inner part 354 of the pipe End of the pipe 36 New replacement valve assembly 40 Standard coupling 40A Inclined tube 425 Inclined surface 430 Proximal end of the inclined surface 431 Distal end of the inclined surface 432 Gear box 50 Shaft 51 Drive unit 52 Cutting covering assembly 62 Right cutting covering assembly 621 Left cutting covering assembly 622 Moving cutting covering taper 65 Cutting covering expansion spring 67 Proximal end of the cutting covering expansion spring 671 Distal end of the cutting covering expansion spring 672 Rod 72 Cutting gap 77 Receiving cavity 87 Wedging rubber 88 Lower housing 9A Upper housing 9B Strong back 16 Adjustable support bracket 19A Screw jack for the support bracket 19B Cutter tool holding member 30B

DETAILED DESCRIPTION OF THE INVENTION

[0011] This method uses the natural movement of the gate valve isolator to push or move the inner seal by the movement of a valve that can be inserted into the hole at the end of an existing pipe. By closing the gate valve isolator, two temporary seals on both sides of the inserted valve are moved to a predetermined position to cover the entire gap formed by cutting the pipe to insert the valve.

[0012] These seals temporarily cover the cut formed in the pipe in a fluid-tight manner between the end of the new valve and the existing pipe end until a permanent external seal can be installed. This process is applicable to most known pipe types.

[0013] The method allows for setting a temporary seal inside the pipe section and installing a much smaller permanent joint after the housing is removed in an open, non-pressurized environment, reducing the size, weight, and many difficulties that complicate valve insertion into the pipe. Bells and plugs may be required, and there may be applications where other connections are conceivable. The use of these alternative connections does not detract from the spirit of how to implement the restraint method for PCCP pipes and what changes the presented new sealing technology will bring to the industry.

[0014] The new processes and products to be installed require very little clearance for internal covering. The movement to cover the clearance may be short, but that movement enables the seal to be executed and allows a standard industry gate valve to be installed, and does not require a special large non-standard valve to perform this process.

[0015] Furthermore, it includes a method for restraining the prestressed tension wires of known PCCP pipes, and a new method of cutting and removing a pipe section and then installing a new valve and joining the new valve to the exposed pipe end with the pipeline fully pressurized. PCCP pipes are manufactured using a thin steel cylinder to provide a fluid-tight membrane and employ wires wound under high tension around this cylinder to contain the internal pressure used in the pipeline system.

[0016] This method installs new valves not only in PCCP pipes but also in most types of pipelines. Steel, PVC, ductile iron, copper, stainless steel, transite A / C, and cast iron pipes can all utilize this method to insert new valves. Since these other types of pipes are manufactured from a single material, they do not require a restraint method and, as will be described in detail, allow for the safe removal of concrete or wire to expose the working area of the smooth pipe cylinder.

[0017] In the case of PCCP, a central clamp is used to hold the central portion for cutting, and in other pipe types, it allows the cutting portion to be lifted within the bonnet as shown, but in pipes that are not PCCP, a permanent restraint does not need to be left in place. The process for PCCP pipes and single-wall pipe types can be carried out in the same way except for the point of restraining the concrete and wire on the PCCP pipe to expose the working area of the smooth cylinder. In other pipe types, a smooth cylinder surface exists without a restraint process.

[0018] PCCP pipes have been installed for many years. When old control valves wear out, new shut-off valves are needed, and when changes or repairs are required in the system, new valves need to be shut off. The thin steel cylinders used in PCCP cannot maintain the operating pressure of the pipeline without leaving the support tension wires in place. Processes and systems for removing wires to insert gate valves have not been known until now.

[0019] The tension wires are embedded and covered with a concrete coating to hold the wires in place and protect the wires from damage and corrosion. To increase the pressure rating, the wires are wound around the outer diameter of the steel cylinder under high tension. In a PCCP pipe, if the tension wires are cut or damaged, the tension wires will be released from the cylinder, reducing the strength of the pipe. According to the present invention, it is possible to restrain and cut the wires without worrying about the wires being released from the cylinder. In this system, there is also provided the ability to remove at least one of the restraints together with a pipe section and replace its central restraint with a valve while the pipeline is fully pressurized without the risk of the wires being released from the steel cylinder.

[0020] A PCCP pipe is composed of a circular carbon steel cylinder around which wires are wound, and provides a concrete lining and a concrete coating. This configuration of different materials makes it impossible to install a known type of insertion system in a PCCP pipe. Even if the insert body is fixed to the PCCP concrete coating with bolts, a fluid-tight seal cannot be achieved. Also, when the concrete is removed to expose the wires, the surface becomes uneven due to the wires being wound around the cylinder, resulting in a non-smooth surface for permanent sealing. Furthermore, the tension wires from the PCCP cylinder in a long region for installing the valve body cannot be removed without compromising the integrity of the pipe.

[0021] The method is developed to expose a short and smooth working area of the PCCP pipe cylinder that includes restraining the PCCP tension wires along different locations of the pipe and where permanent and temporary joints can be installed and removed. The method includes steps of restraining a part of the pipe using a central restraint clamp to support that area, removing a part of the pipe, creating an area for inserting a valve installed at the end of the pipe and a seal that can be easily inserted inside, resulting in reducing the number of wires removable from the structure of the host pipe.

[0022] In a PCCP pipe, this process provides at least two outer restraint clamps that are mechanically installed on the pipe coating to permanently hold the internal tension wires of the coating. Further, at least one temporary central restraint clamp surrounding the concrete coating is used to hold the wires, and when the pipe is cut, this central clamp becomes a sacrificial clamp and is removed along with the cut portion of the pipe. This installation of the clamps provides at least two locations where a smooth steel cylinder is safely exposed and a temporary housing can be attached. By being able to remove the central clamp under pressure with the cut pipe, a method of supporting the pipe is provided when necessary, and when the restraint of the pipe is no longer required, it is removed under pressure along with the clamp to create space for a new valve.

[0023] As illustrated in this method, by providing at least three restraint clamps surrounding the concrete coating, the tension wires are held in place so that valve insertion can be performed in a fully pressurized PCCP pipeline.

[0024] This process provides various restraint mechanisms or "clamps" for holding the wires in place by fixing the concrete that holds the embedded wires. The term "clamp" is understood to refer to one clamp or a combination of multiple clamps used for the purpose of surrounding the concrete coating of the pipeline and holding it under tension to hold the wires in place. Since the clamp can be tightened around the concrete coating, it enables the clamp to firmly hold the concrete and the embedded wires in place.

[0025] To initiate the restraint process, at least three clamps are used to prepare the pipe for valve insertion. The central restraint clamp has approximately the same width as the portion of the pipe to be cut, and the main function of this central clamp is to support and hold a portion of the pipe by retaining the wire within the pipe coating until the pipe portion is cut and the central clamp is removed and discarded along with the pressurized pipe portion. In addition to the central clamp, at least one outer clamp is installed on each side of the central clamp to permanently hold the concrete and wire that support the pipe from internal pressure.

[0026] In PCCP pipes, a space is provided between the central clamp and each outer clamp, enabling the removal of the concrete and wire and exposing the smooth steel cylinders on both sides of the central clamp. This area of the exposed smooth PCCP cylinder allows for the installation of a pressure-retaining container or "housing" that can be installed in a narrow area on the cylinder.

[0027] The exposed smooth area needs to be made as short as possible. Depending on the application, it may be necessary to use additional clamps to remove two or more areas of concrete and wire and expose a smoother working area, thereby additionally securing a short clear working area. If necessary, at least a second set of outer clamps can be installed some distance outside the first outer clamp to hold the concrete and wire.

[0028] This second set of clamps is located some distance away, and additional clamps can be installed outside the first outer clamp to obtain additional working areas. This process can provide additional access areas to the smooth cylinder, allowing the housing ground and the working area to be installed in separate areas along the outside of the cylinder.

[0029] The housing attached to the pipe cylinder has means for receiving a service valve mounted on the upper part and functioning as a fluid isolator for the bonnet. Thus, with the pipeline pressurized, tools can be installed and removed to complete the installation of a new insert valve. The bonnets used in this system and method are known in the art and are described, for example, in U.S. Patent Nos. 6,983,759, 6,776,184, 7,021,325, and 7,021,325. A temporary pressure-resistant housing is installed on the host pipe in a fluid-tight configuration and seals the pipe wall and the PCCP seal within a short region of the provided smooth cylinder. Since the pressure-resistant housing is divided into at least two half parts, each end of the container can be assembled to the existing pipeline using split mechanical drag lands, and a split tapered wedge-shaped rubber gasket is pushed into the wedge-shaped rubber receiving area on the housing to form a fluid-tight seal.

[0030] The pressure-resistant housing is constructed to surround a central clamp and the pipe in question. The housing provides support for a service valve that enables various functions to complete the insertion of the valve.

[0031] Furthermore, the bonnet of the present system is designed to be large enough to accommodate the stabilization member and the cutting mechanism, and, if necessary, provides sufficient space to receive the cut portion of the pipe and the central clamp together with the cutting mechanism and the stabilization member at once. First, a bonnet housing having the stabilization member and the cutting mechanism is held on the service valve. The stabilization member extends until it reaches the central clamp, and both are firmly fixed by bolting or screwing. When the stabilization member is fixed by the central clamp, the bonnet housing can be lowered by the cutting mechanism using the stabilization mechanism and fixed to the open service valve in a fluid-tight configuration. When fixed to the open service valve, the cutting mechanism can be lowered to a predetermined position by a known advancement mechanism such as a screw jack and a packing seal to prevent fluid from leaking out of the bonnet. When the stabilization member is attached to the central clamp, the pipe to be cut is held in a precise position. The housing has a pipe support that can be advanced or tightened against an exposed cylinder or central clamp that helps to firmly hold the pipe portion to be cut. The cutting mechanism starts cutting at the top of the pipe and passes through the entire pipe portion.

[0032] The cutting mechanism can use various known methods such as wet tapping where a hole saw is used and a round cutter cuts off the entire portion of the pipe. Diagrams of alternative methods known as hot tapping are included in FIGS. 26, 27, 28, and 29. Known hot tapping methods may use a pilot drill or a holding device for holding the cutting portion to be removed.

[0033] The flexible cutting belt may include cables, wires, or may have a flexible chain similar to a chainsaw. Diamond or known hard particles are attached to perform cutting or abrasive separation of the pipe. The cutting mechanism can cut two paths simultaneously, although depending on the application, one cut may be performed at a time. The flexible cutting tool may have at least one drive wheel for each flexible belt and one or more wheels to firmly hold and enable movement of the flexible belt. The motor for driving the flexible belt may incorporate a direct drive using at least one rod or drive line that can pass through the bonnet and reach one or more gearboxes. Since this rotational movement drives the wheel and supplies power to the belt, the motor can be installed outside the pressure vessel.

[0034] When the cutting part penetrates the pipe wall, the housing is fully pressurized by the pipe contents when the fluid enters the housing. The housing provides a housing for containing the fluid pressure, so that equal pressure acts on the outside and inside of the pipe. As a result, when a uniform pressure is achieved, there is no need to restrain the tension wire at this central location in the pipe section, allowing the central clamp to be sacrificed.

[0035] When the pipe section is completely separated, a stabilizing member or tapping machine is activated to retract and remove a part of the cut pipe or the central restraint clamp. The cutting mechanism can be fully retracted into the bonnet housing together with the stabilizing member, so that the service valve can be closed. Closing the service valve allows depressurization of the bonnet and removal of the bonnet from the service valve along with all the items contained therein. The cut part of the pipe, the central restraint clamp, the pilot drill or the holding device are removed from the stabilizing member or the hole saw, and the cutting mechanism is removed from the bonnet housing.

[0036] The new valve intended for insertion into the pressurization system is positioned and firmly attached to the stabilization member and is moved into the housing of the bonnet. The insertion valve may preferably be set to the open position or the semi-open position prior to insertion into the pipeline. The cutting cover assemblies are installed completely within both ends of the pipe, one on each side of the new valve. The bonnet is reinstalled on the service valve in a fluid-tight configuration, and the bonnet is pressurized by opening the service valve to allow fluid to pass through the bonnet. When the service valve is fully opened, the stabilization member that secures the new valve at the end of the pipe holding the cutting cover assembly is extended to a fully installed and secure position within the gap left by the removed pipe portion. Upper collars with half the diameter provided in various desired shapes may be attached to both ends of the new valve pipe that matches the outer diameter of the existing pipe, ensuring that the holes of the new valve and the existing pipe are accurately aligned in the internal seal passage. The ends of the new valve pipe may take a contour shape that matches the contour shape of the existing pipe ends remaining when cut with a hole saw. The collar may likewise take this contour shape and may remain overhanging to provide accurate alignment.

[0037] The cutting cover seal is wider than the gap formed in the pipe by the cutting tool. The cutting cover seal may incorporate a design useful for sealing the gap created by the pipe being cut. The seal design may include angles, pockets, or any number of different designs conceivable, forming a seal that holds the seal in its desired position and covers and closes the cut or gap in a fluid-tight and structurally sound configuration.

[0038] A spring generating cylinder may be used to form an outward pressure on the seal and maintain the seal on the inner diameter of the pipe wall. The cylinder prevents the fluid pressure from the pipeline from extruding the seal from the cut-off part and holds a new valve in a predetermined position when the service housing is removed. Various types of materials and shapes may be used, but preferably, a composite material formed of split roll tubes overlapping under tension from steel or stainless steel, plastic, and solid tubes is used to match the required diameter and form a round shape that provides an outward extrusion force. The round shape may provide an overlap to achieve the desired expansion required to add a spring to the cylinder. Solid, non-split, or spring tubes formed from various materials are described in detail and shown in FIG. 20.

[0039] This cut-off covering assembly may together provide a spring-type sealing member that supports the installation of the valve when moved to a predetermined position together with the ends of the existing pipe. The cut-off covering assembly is of a hollow shape and is similar to a piston insertion tool used to compress the piston ring before sliding the piston in the engine bore.

[0040] The cut-off covering assembly is first installed at both pipe ends of the new valve. When partially moved to the existing pipe end, the cut-off covering assembly covers the entire cut-off part formed around the inner diameter of the pipe. The cut-off covering assembly preferably becomes half of the end of the new valve and half of the existing pipe to cover the gap in order to form a fluid-tight seal. However, in order to perform the seal, it is not necessary for half of the cut-off covering assembly to reach half inside the existing pipe.

[0041] One embodiment provides one or more cross braces that are used with a cut-off covering assembly and that abut against the gate of a valve and move with the gate, such that when the gate isolator is closed, the gate may contact the cross braces directly or may contact an intermediate member that contacts the cut-off covering assembly. The cross braces may be installed at an angle or may include a wedge-shaped configuration in the cut-off covering assembly, such that when the gate is actuated toward the closed position, the opposite cut-off covering assembly is pushed toward the existing pipe bore. By using one or more springs attached to the cut-off covering assembly, when the gate pressure is removed and reversed, the wedge-shaped configuration may be retracted to return to its original position. When the gate valve operator is preferably rotated in the closing direction, a round rod passing through the bonnet of the service valve provides a movement similar to a screw jack. A packing seal is provided in the bonnet around the actuating rod to prevent fluid from leaking outwards from the bonnet, and by rotating the operator of the new valve toward the closed position, the movement of the gate pushes both cut-off covering assemblies into both existing holes of the cut pipe. As the gate moves along the angled cut-off covering assembly surface, the linear movement of the gate causes the cut-off covering assembly to move away from the gate to a sealing position, covering the gap between the end of the new valve pipe and the existing pipe. In one embodiment, the movement of the gate pushes at least one tapered cross brace or intermediate member, and the cut-off covering assembly slides into the bore of the existing pipe and reaches a predetermined position within the end of the existing pipe. There are many ways to move the cut-off covering assembly, but this is a simple way to achieve this requirement.

[0042] Preferably, with the pipe end of the new valve aligned with the existing cut pipe end, the gate of the valve is moved towards the closed position, whereby the isolator is engaged with the cross braces of the cut covering assemblies installed on both sides of the gate. As the gate continues to close, the gate slides across the cut covering assemblies, and by their wedge shape, the gate partially pushes the cut covering assemblies from their positions within the end of the new valve pipe into the end of the existing pipe, covering the gap left by the cut of the pipe. Both cut covering assemblies are simultaneously pushed and slid in opposite directions in the same manner from the end of the new valve pipe to the cut end of the existing pipe. A portion of the cut covering assembly remains within the end of the new valve pipe and a portion moves into the existing pipe, where the gap left by the cut of the pipe is covered. The seal is set in a fluid-tight state by reducing the pressure in the service housing. The outward spring action of the tube helps to provide uniform movement by maintaining the cut covering assembly pressed against the inner diameter of the end of the new valve and against the existing pipe wall during movement, although solid tubes without a spring effect may be used for various applications. This movement positions the seal to cover the gap for the pressure reduction in the service housing. When the service housing is depressurized, the cut covering assembly tightly seals the new valve to the end of the existing pipe. If desired, the operation of the new valve can be reversed by opening the new valve and using one or more springs installed in the cut covering assembly to retract the cut covering assembly back to its pre-operated position.

[0043] Semicircular collars that match the outer diameter of the existing pipe and are attached and overlap are installed on top of the pipe ends of each new valve. These collars allow for precise vertical and horizontal alignment, and when the new valve is set at the cut portion of the pipe under tension, the centering collar meshes with the O.D. (outer diameter) of the existing pipe, and when the centering collar is firmly fixed between the new valve and the cut portion of the pipe, it forms an accurate alignment. When the new valve is in place with the existing pipe and the cutover assembly is advanced into the hole in the existing pipe that covers the gap, the pressurized housing used in the insertion process can be depressurized. When depressurization is performed, the cutover seal is firmly pressed against the inner wall by the internal pressure of the existing pipeline, the seal is fixed fluid-tight, and the tube or spring tube temporarily holds the new valve in place. The rigid spring tube prevents the seal from being extruded from the cut gap, and a conventional pipe joint coupling is placed around the outside of the gap portion to restrain the new valve in place until the cut area is firmly covered as a permanent completion of the valve installation. At this point, the pressurized housing can be removed or partially removed (see FIGS. 26, 27, 30, and 31).

[0044] As shown in FIGS. 1 to 3, a known method of restraining the tension wire and removing the pipe portion is repeated to assist in the description of the present invention. The tension wire 1 is embedded in the concrete coating 5 of the PCCP pipe 35. The restraining clamp 2 remains permanently as part of the pipeline 35, maintaining the wire 1 under tension around the cylinder 7 to ensure the strength of the pipeline 35. The central restraining clamp 3 is temporary and is installed a short distance away from the outer clamp 2, providing a smooth area of the cylinder 7 without the wire 1 and concrete 5 without risking loss of strength of the pipe 35. The clamp may be formed from a combination of parts joined, for example, by bolts 4 as shown in the illustrated embodiment. The restraining clamps 2 and 3 are designed to hold pipelines 35 of various sizes and to withstand the internal operating pressure. A mortar mix may be applied to form a non-circular surface of the concrete 5.

[0045] The central restraining clamp 3 may be formed by combining a plurality of parts to form one clamp, or may be formed by combining clamps having a plurality of parts as shown in FIG. 1, to form the central restraining clamp 3. The central clamp 3 is provided with a mounting flange 6 intended to fit onto the stabilizing member 15 shown in FIGS. 7, 8 and 9. The stabilizing member 15 is preferably attached to the mounting flange 6 by a common thread or by bolting. Threading is preferred as it allows the stabilizing member to be attached and removed (threaded in and out) under pressure. The central restraining clamp 3 is installed around the pipeline 35 surrounding the concrete coating 5 to secure the tension wire 1 that supports the cylinder 7.

[0046] The clamps 2 and 3 are preferably assembled by bolt tightening 4, and the outer clamp 2 is installed at a predetermined distance outside the central clamp 3. The outer restraint clamp 2 may be composed of a single clamp, or a plurality of clamps may be combined to form the outer restraint clamp 2. Bolts and nuts 4 are used to assemble the restraint clamps 2 and 3. These outer restraint clamps 2 may remain as a permanent part of the pipeline 35. By leaving a plurality of outer restraint clamps at a predetermined position, additional service locations may be provided along the steel cylinder 7 for tools or services. For example, as can be seen in FIG. 17, a second left restraint clamp 2A disposed on the left side of the left restraint clamp 211 and a second right restraint clamp 2B disposed on the right side of the right restraint clamp 212 may be attached to the pipe 35.

[0047] The central restraint clamp 3, as can be seen in FIGS. 1 to 4, may have a width smaller than that of the new valve 22 having its sub-assembly 21 so as to allow the cutting tool to pass through. As can be seen in FIG. 9, the central restraint clamp 3 is removed from its position together with the pipe portion 20. When the portion 20 is cut by the cutting tool 30 (see FIGS. 5 and 7), the removal of this portion 20 includes the removal of the central restraint clamp 3 as shown in FIG. 9 while the pipeline 35 is fully pressurized. The housing 9 makes it possible to equalize the pressure inside and outside the pipeline 35, so that the removal of the cut portion 20 can be carried out. The removal of the central restraint clamp 3 together with the cut portion 20 is not carried out unless the pressure of the pipeline 35 is equal. When the wire 1 is cut to expose the smooth cylinder 7 and the clamp 3 is removed, the wire 1 separates from the cylinder 7, and the unsupported cylinder 7 has a risk of bursting after the wire 1 is removed.

[0048] Using the method of the present invention, by encapsulating the central restraint clamp 3 in the housing 9 and equalizing the external pressure on the pipeline 35 to the same pressure as inside the pipeline 35, no stress due to internal pressure is generated in the cylinder 7. This enables the safe execution of cutting and removing the central restraint clamp 3 from the pipeline 35 together with the pipe portion 20. Further, the uniform pressure generated by the housing 9 enables the cutting cover assembly 62 to be inserted smoothly with little resistance and without the fluid pressure escaping from the cutting gap 77. Non-uniform pressure affects the movement of the cutting cover assembly 62 towards the pipe end 36.

[0049] Figure 4 shows a pressurized housing 9 assembled to the pipeline 35 using a mechanical seal or gland 11 that presses and compresses a wedge-shaped rubber (elastomer) gasket 88 into the receiving cavity 87 on the opposite side of the housing 9 by bolt tightening. The gasket 88 preferably surrounds the pipe, is cut at a taper angle to form a wedge, and is wrapped around the pipe within the cavity 87 so that when the ring member 11 is tightened, it is compressed around the entire pipe to seal the cut rubber edge and form a mechanical joint. This multi-component housing 9 is installed in the empty area of the cylinder 7 or on the smooth pipe 35.

[0050] The housing 9 has a mounting surface 28A to which a service valve 10 is connected so that the bonnet 32 can be installed, removed, and various services can be performed. The bonnet 32 is attached with a stabilizing member 15 that can be retracted and advanced to restrain the clamp 3 by the mounting flange 6. The clamp 3 is attached to the pipe portion 20 and holds the pipe portion in a predetermined position for cutting. As shown in FIGS. 5 and 6, an abrasive belt 13 that rotates on the cutting tool 30 can be used.

[0051] FIG. 5 shows a cutting tool 30 of a known type having at least one gearbox 50, the gearbox 50 being provided to be drivable by a shaft 51 that connects to a drive unit 52 through a housing 9 or a bonnet 32, so that the belt 13 can move to cut a pipeline 35. By using an external drive device 52, it is possible for a hydraulic drive device or an electric drive device 52 not to be placed in water or pressurized within the housing 9. The provided wheel 12 firmly holds the belt 13 and drives the belt to perform the cutting of a part of the pipe 20 from the pipeline 35 shown in FIG. 9.

[0052] FIG. 6 is a plan view of a known cutting tool 30. It shows the positions of both a polishing belt 13 rotated by a wheel 12 and a drive provided by a shaft 52.

[0053] In FIG. 7, a forward screw jack 17 moves the cutter 30 downward from the bonnet 32 into the housing 9. The forward movement of the cutter 30 is indicated by an arrow, and the tool 30 is moving towards the pipeline 35.

[0054] In FIG. 8, it is shown that the cutter 30 cuts the pipeline 35 to form a cut portion 20 shown in FIG. 9. While the tool 30 rotates the polishing cutting belt 13 and separates a part of the pipeline 35, the forward movement of the cutter 30 is indicated by an arrow.

[0055] In FIG. 9, the cut portion 20 attached to the clamp 3 and remaining within the cutting tool 30 is retracted into the bonnet 32 by a member 15. When retracted, the service valve 10 may be closed to cut off the pressure within the existing pipeline 35 and the housing 9. Since the tool 30 and the cut portion 20 are retracted and returned into the bonnet 32, the bonnet 32 is removable from the service valve 10. A received cutting gap 77 is formed and shown in the pipeline 35 that exposes the existing pipe end 36.

[0056] Figure 10 shows a new valve 22 with the pipe ends 21 attached, and both pipe ends 21 include a cut-off covering assembly 62 shown in FIGS. 14, 15 and 16. The O.D. (outer diameter) centering collar 28 is attached to the pipe ends 21 of each new valve to provide accurate alignment with the outer diameter of the existing pipe end 36. The cut-off covering assembly 62 is disposed within each pipe end 21 and attached to the new valve body 22 to form a new replacement valve assembly 40. Since the new replacement valve assembly 40 is fixed to the stabilizing member 15 and retracted into the bonnet 32, the service bonnet 32 can be bolted to the service shut-off valve 10. When the bonnet 32 is fixed to the service valve 10, the service valve 10 is fully opened to apply pressure to the bonnet 32, from which the pipe portion 20 is cut, and the stabilizing member 15 is advanced into the cut-off gap 77 as seen on both sides of the cut-off gap 77 and also as seen in FIGS. 9 and 10, enabling the installation of a new replacement valve assembly 40 including the pipe end assembly 21 by removing it from the existing pipeline 35 forming the existing open pipe end 36.

[0057] In FIG. 11, a new replacement valve assembly 40 is shown that includes a pipette end 21 with a cut-away cover assembly 62 as seen in FIG. 12A, and is set to be aligned with an existing pipe end 36 using an O.D. (outer diameter) centering collar 28. The new replacement valve assembly 40 is moved to a predetermined position by a stabilizing member 15. The O.D. centering collar 28 is connected to each pipe end 21 and provides a semi-circle designed to overlap and cover the existing pipeline 35. The O.D. (outer diameter) centering collar 28 has an inner diameter that is the same as the outer diameter of the existing pipe 35, and preferably surrounds half of the pipe (from the top of the pipe to the spring line on each side of the pipe) when the new replacement valve assembly 40 is torqued or pushed into place. This procedure is designed to hold and accurately align the new replacement valve assembly 40 in the correct position by insertion with the stabilizing member 15. This procedure firmly and accurately installs the new replacement valve assembly 40. The O.D. centering collar accurately aligns and moves the new replacement valve assembly 40 to precisely align both the holes in the pipette end 21 and the holes in the existing pipe end 36. The inner diameter of the pipe 21 and the existing pipe end 36 are aligned with each other and arranged on the same plane. This allows the cut-away cover assembly 62 as seen in FIG. 13A to easily slide through all the holes in the pipe end without restriction and cover the gap 77.

[0058] Figure 12 shows a new replacement valve assembly 40 set within an existing gap 77 formed by the cutting tool 30. The cutting sheath assembly 62 is arranged to move within the illustrated existing pipe end 36. After replacement, the new valve assembly 40 having the sub-assembly 21 is positioned in place, and by rotating the control rod 72 as seen in Figure 12A, the new valve 22 is actuated within the pressure housing 9, and the isolator 29 of the new gate valve 22 may be closed as seen in Figures 11, 12A, and 13. As also indicated by the arrow in Figure 13, by rotating the actuator nut 23 of the valve 22, the control rod 72 is actuated in the closing direction. This rotation causes the gate 29 to advance in the closing direction.

[0059] Each of the pipe ends 21 of the new replacement valve assembly 40 includes the cutting sheath assembly 62, and various moving components for advancing the cutting sheath assembly 62 using a taper or mechanical means may be contemplated by the linear force generated by the closing force of the gate 29.

[0060] Figure 12A shows that the gate 29 is closed by rotating the actuating nut 23. As the valve 29 is moved between a first position and a second position (downward in the vertical direction in the illustrated embodiment), the distal end 294 of the valve 29 contacts the relatively proximal (upper) end 431 of the inclined surfaces 430 on both sides of the valve assembly 40. As the valve 29 continues to move, the valve contacts the more distal surface 432 of the inclined surface 430 and exerts pressure (downward and outward in the illustrated embodiment). When the right side 291 of the valve contacts the inclined surface 430 of the right tube 256, the right side 291 pushes the right end of the right cutting cover assembly out of the right cylindrical opening 224. At the same time, when the left side 292 of the valve contacts the inclined surface 430 of the left tube, the left side 292 pushes the left end of the left cutting cover assembly out of the left cylindrical opening 226. The gate moves linearly while in direct contact with the moving cutting cover taper 65, i.e., the inclined surface 430 of the cutting cover assembly 62, moving the cutting cover assembly 62 away from the gates 29 on both sides and moving the cutting cover assembly 62 from its fixed position within the pipe 21 into the pipe end 36.

[0061] In Figure 13, the cutting cover assembly 62 is mechanically moved by rotating the rod 72 through the bonnet 32. This rotational movement of the valve 22 that actuates the nut 23 installs both cutting cover assemblies 62 into the existing opposite pipe ends 36 to cover the remaining gap 77. At that point, the new valve 22 and its gate 29 are preferably in a semi-closed position relative to the closed position. The cutting cover assembly 62 may remain in place by the tension generated by the split tube or spring tube 25 and the seal 26 until the service housing 9 is depressurized. The cutting cover assembly 62 is partially installed into the existing pipe end 36 to at least a position sufficient to cover the cutting gap 77, as can be seen in Figures 13, 14, and 16.

[0062] Optionally, at least one cutting cover return spring 67 shown in FIG. 13 may be used to effect a retraction of the cutting cover assembly 62. In this embodiment, the proximal end 671 of the return spring 67 is attached to or otherwise mechanically connected to an inner portion of the cutting cover assembly (adjacent to the central chamber 227), such as a tube or conduit of the cutting cover assembly, and the distal end 672 of the return spring is attached to or otherwise mechanically connected to the housing of the valve assembly, such as within the central chamber 227.

[0063] FIG. 14 shows an embodiment in which the right cutting cover assembly 621 is positioned within the interior 2251 of the right cylinder 223 and the left cutting cover assembly 622 is positioned within the interior 2231 of the left cylinder 226. Each cutting cover assembly may include an elastomeric seal 26 and a tube 255, which may be a split tube or a spring tube 25, and may optionally include a cross brace 27 visible in FIG. 17. The outer surface 261 of the elastomeric seal 26 contacts the inner surface of the cylinder of the new replacement valve assembly 40, and the outer surface 251 of the tube 255 contacts the inner surface 262 of the elastomeric seal 26. The spring tube 25 may be used to exert pressure (force) outwardly, i.e., against the inner surface 262 of the elastomeric seal 26, thereby helping to create a fluid-tight seal with the seal 26. The tube 255 or spring tube 25 may be installed relative to the inner pipe end 21, or the seal may be installed relative to the pipe end 21, or both configurations may be used.

[0064] One or more cross braces 27 extend into the fluid passage 228 of the new replacement valve assembly 40 in the central portion of the cutting sheath assembly 621 and may extend between a first position 2251 on the inner surface of the spring tube and a second position 2231 on the inner surface of the spring tube 25. The wedge shape of the spring tube 25 may include a cross brace or rod 27 (shown in FIG. 17) and assists in the movement from the linear force acting on the wedge-shaped spring tube 25, so that the cutting sheath assembly 62 moves outwardly without damaging the spring tube 25 as can be seen in FIGS. 14, 12A and 13. When the linear movement of the gate 29 is advanced toward the closed position between the first and second positions, the side surface 291 of the valve gate contacts the contour tube 425 of the right cylinder 223 and urges the right end of the right cutting sheath assembly 621 out of the right cylinder opening 223, i.e., the seal 26 and the inclined tube 425 may be moved into the open end 36 of the cutting pipe 35 adjacent to the right side of the new replacement valve assembly 40. At the same time, the second side surface 242 of the valve gate 29 (opposite the first side surface of the gate) contacts the inclined tube 425 on the left side of the cylinder 226 and urges the left end of the left cutting sheath assembly 622 out of the left cylindrical opening 226 and into the open end of the cutting pipe 36 adjacent to the right side of the new replacement valve assembly 40. In this way, the two open ends of the new replacement valve assembly 40 may be arranged to be in fluid communication with and fluid-tightly engaged with the cut end of the pipeline 35.

[0065] FIG. 15 shows the spring tube 25 as part of the cutting sheath assembly 62. The spring tube 25 may be sized to provide an outward expansion that helps hold the seal 26 against the pipe wall 21 and inside the pipe diameter 36 and may be wound larger in segments.

[0066] FIG. 16 shows the outer surface 251 of the spring tube 25 that moves and adheres to the elastomeric seal 26. In another order, the inner surface 252 of the spring tube is similarly enabled to move and adhere to the elastomeric seal 26, such that the spring tube 25 rides directly against the inner diameter of the pipe end and the elastomeric seal 26 covers the spring tube 25.

[0067] FIGS. 17 and 19 show one embodiment of moving the cutover sheath assembly 62 using at least one rod. The illustrated cross brace 27 is angled to produce a wedging action by the gate 29, and movement of the gate mechanically pushes out the cross brace 27 during the closing movement of the gate 29 to move the cutover sheath assembly 26 into the pipe end 36. This figure shows two cross braces 27 within the spring tube 25.

[0068] FIG. 18 shows an inclined tube surface 425 having a structure that can conform to the shape of gate 29 as seen in FIG. 14. As gate 29 moves toward the closed position, the gate contacts the inclined tube surface 425, which may be wedge-shaped, to cover gap 77 as the cut-off covering seal 26 is moved outwardly through pipe end 21 and into pipe end 36. The inclined tube surface 425 may be used as a wedge-shaped extrusion member without adding cross braces 27 to move the cut-off covering assembly 62. This inclined tube, shown as split 25, may alternatively be provided as a solid having no split spring shape and may be formed from any of a number of optional materials such as PVC, HDPE, composites, hard rubber, metal, or plastic. In this embodiment, the tube 255 of the cut-off covering assembly 62 is an inclined tube 425 having an inclined surface 430 at its inner end adjacent to the central chamber 227 (e.g., the right tube of the cut-off covering assembly or the left side of the conduit). As gate 29 is moved vertically downward as in the illustrated embodiment, the inclined surface 430 is inclined downwardly and outwardly from the proximal (upper) end 431 to the distal (lower) end 432. The inclined surface 430 between the proximal (upper) end 431 and the distal (lower) end 432 preferably should form an angle of less than 90° with respect to a virtual horizontal plane extending through the conduit, such as angle Θ shown in the embodiment of FIG. 21.

[0069] Figures 19 - 21 show an embodiment in which an inclined surface 430 is formed by a cross brace 27 including a wedge - shaped attachment that provides a wedge or pushing effect to cause the two cutting cover assemblies 62 to separate from each other when the gate 29 is pushed between the two cutting cover assemblies 62, as shown in FIGS. 12 and 12A. In certain embodiments, the cutting cover assembly 62 may include both a first cross brace 271 and a second cross brace 272. The cross brace 27 may optionally include a rod that extends inwardly towards the central chamber 227 to improve contact with the movable gate 29. In the illustrated embodiment, a bent rod attached across a spring tube 25 that may be incorporated with the cross brace 27 is shown. The bent rod has an intermediate flange 275 with an upper end 276 and a lower end 277. FIG. 20 shows an alternative view of FIG. 19.

[0070] FIG. 21 shows how the downward movement of the gate 29, indicated by arrow A, is transmitted to the lateral movement of the cutting cover assembly 62, indicated by arrow B, by pushing the wedge - shaped rod 27 or the moving cutting cover taper 65 and applying a force along the inclined surface 430 from the upper end 276 to the lower end 277. The pipe end 21 forming the new replacement valve assembly 40 restrains the cutting cover assembly 62 and allows the energy to provide only lateral movement. This enables the linear movement to be transmitted to move the cutting cover assembly 62 to cover the gap 77 and also to move within the pipe end 36.

[0071] In FIG. 22, when the cutting cover assembly 62 moves to a position covering the gap 77, the pressure inside the housing 9 is released, and the cutting cover assembly 62 is firmly fixed to the inner walls of the pipe 35 and the pipe assembly 21. When the housing 9 is depressurized, the housing 9 may be removed from around the pipeline 35, and upon completion, a permanent external closure coupling 40A is installed to cover the gap 77 and seal the pipe end 21 and the existing pipe 35 to complete the insertion of the valve. Alternatively, instead of using the closure joint 40A, a closure joint for the steel pipeline 35 may be welded.

[0072] FIG. 23 is a perspective view of a pressurized housing 9 including a service valve 10 with a bonnet 32 attached to the pressurized housing 9. The pressurized housing 9 is assembled around an existing pipeline 35. The left side of the existing pipeline is indicated by 225 and sealed by a left split machine ground 11 (not shown), and the right side of the existing pipeline is indicated by 223 and sealed by a right split machine ground 11. The lower pressurized housing 9A and the upper pressurized housing 9B are assembled in a fluid-tight configuration, and stabilizing members 15 and screw jacks 17 (not shown) are attached to the bonnet 32.

[0073] FIG. 24 is a front view of a pressurized housing 9 assembled around an existing pipeline 35 including a service valve 10 attached to the upper housing 9, and then the bonnet 32 is attached to the fixed service valve 10. A machine ground 11 for sealing the housing 9 to the existing pipeline 35 is shown. The lower pressurized housing 9A and the upper pressurized housing 9B are assembled in a fluid-tight configuration, and a stabilizing member 15 and a screw jack 17 (not shown) are attached to the bonnet 32.

[0074] Figure 25 is a side cross-sectional view of the pressure housing 9 including the service valve 10 and the bonnet 32 assembled on the existing pipeline 35. The service valve and bonnet with a cutting tool installed along the line A-A in Figure 25, the stabilizing member 15 and the screw jack 17 (not shown) are attached to the bonnet 32.

[0075] Figure 26 shows in more detail how the pressure housing 9 is assembled around the pipeline 35. Both wedge-shaped rubbers 88 are shown wound around the existing pipe 35 and both mechanical grounds 11 are bolted around the pipeline 35. The pressure housing 9 assembly shown in the figure is installed around the defective valve 20A found in the pipe section 20 that needs to be removed. The pressure housing 9 may provide a part of its structure called the strong back shown at 16 to leave it as needed. This image shows the strong back 16 installed as part of the pressure housing 9.

[0076] Figure 27 shows the pressure housing 9 installed on the pipeline 35 including an adjustable support bracket 19A that supports the existing pipe section 20 being prepared for cutting. The adjustable support bracket 19A is installed on the lower half 9A of the pressure housing 9. The support is achieved by rotating a handle 19B on the outside of the pressure housing 9, which functions in the same way as rotating an acme screw through a nut combination of nuts for advancing or retracting the adjustable support bracket 19A. By moving in one direction, the adjustable support bracket 19A applies pressure to the cutting section 20, and when the rotation is reversed, the adjustable support bracket 19A retracts under the cutting section 20, ensuring space for installing a new valve assembly 40 as needed. It is operably adjustable from the outside of the pressure housing 9, realizing the mechanical support pipe 35 and accessories. The fluid seal within the pressure housing 9 can be implemented by known flexible seals such as O-ring materials.

[0077] FIG. 28 is a side view of a wet tapping 31 for cutting the pipe portion 20 to remove this part of the pipe 20 from the pipeline 35. The wet tapping tool 31 is used to install a new valve assembly 40 under pressure using a wet tapping machine tool 31. This figure shows where the tapping tool hole saw has started to cut the top of the pipeline 35, and its cutter tool holding member 30B is included to capture the existing valve 20A that is removed along with the cut pipe portion 20 shown in FIG. 29 and any attachments that may be in the pipeline 35.

[0078] In FIG. 29, it shows the hole saw 33 cutting the pipe, and it is shown that the tool holding member 30B captures the existing valve having the pipe portion 20A that is to be removed together with the cut portion 20 of the pipeline 35. FIG. 29 shows in detail the pipe portion 20 that is removed within the hole saw 33, retracted above the service valve 10, and housed in the upper bonnet 32. At this point, the wet tapping tool 31 having its housing is removable. It is shown that the screw jack adjustment of the adjustable support bracket 19A will be slightly lowered after cutting the pipe portion 20 to create space for the new valve assembly 40.

[0079] In FIG. 30, the wet tapping tool 31 discards the cut pipe portion 20 and changes it to a new valve assembly 40, and by moving the wet tapping tool 31 to fully install the new valve assembly 40, it moves the new gate isolator and sets and seals the cut covering assembly 62 within the existing pipe end 36. The pressurized upper housing 9B and the pressurized lower housing 9A shown are selectively removed as required. The strong back 16 is shown to remain as it is temporarily or permanently as required.

[0080] Figure 31 shows an embodiment of a restraint portion of the strongback 16 that can be left to hold the assembly of the new valve assembly 40 in place. This strongback 16 may be left as is until another restraint means is installed, or may optionally be left permanently as needed.

[0081] Figure 32 is a side view of an embodiment of the pressurized housing 9 shown as being assembled to an existing pipeline. An adjustable support bracket 19A attached to the lower housing 9A is shown.

[0082] Figure 33 is a perspective view of an embodiment of the pressurized housing 9 shown as being assembled on an existing pipeline 35. The existing pipeline 35 is shown housed and exposed for cutting and removal.

[0083] Figure 34 is a front view of an embodiment of the pressurized housing 9 shown as being assembled on an existing pipeline 35. An adjustable support bracket 19A attached to the lower housing 9A is shown. Bolts for assembling the housing are presented.

[0084] Figure 35 is a side view of an embodiment of a new valve assembly 40 installed within a pipeline 35, showing one means of temporarily installing an O.D. outer diameter centering collar 28 to a new valve end 21 by fixing the restraint clamp 2 with bolts 4 and flaring one side of the centering collar 28 to match its inner diameter to the outer diameter of the existing pipe 35.

[0085] The examples described in this specification are provided to illustrate specific concepts of the present disclosure. The apparatuses, devices, or components shown above may be configured to perform one or more of the methods, features, or steps described herein. Those skilled in the art will recognize that these are merely illustrative, and other examples may fall within the scope of the disclosure and the appended claims. Based on the teachings herein, those skilled in the art will understand that the aspects disclosed herein may be implemented independently of any other aspect, and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented using any number of the aspects described herein, or a method may be performed. Further, in addition to or separate from one or more of the aspects described herein, such an apparatus may be implemented or such a method may be performed using other structures, functions, or structures and features.

[0086] Definitions As used herein, the following terms and their variations have the meanings set forth below, unless the context in which the term is used clearly indicates a different intended meaning.

[0087] "About" and "approximately" refer to an amount within 10% of the stated amount, preferably within 5% of the stated amount.

[0088] "Brace" refers to a structural component attached to a structure to reinforce and / or support the structure.

[0089] "Clamp" refers to a component that applies pressure to the outer surface of a pipe in the present system. The clamps used in the present system and method exert a restraining force sufficient to restrain the tension wires on the PCCP pipe with a force sufficient to prevent the loss of tension in the tension wires.

[0090] A "gate valve" refers to a control valve that allows fluid to pass through the valve without obstruction or stops the fluid flow. A gate valve opens by retracting a barrier (gate) from the fluid path. The faces of the gate valve may be parallel, but are usually inclined, i.e., wedge-shaped.

[0091] "Horizontal" refers to a plane or direction that is substantially perpendicular to the surface on which the valve assembly is placed. "Vertical" refers to a plane or direction that is perpendicular to the horizontal plane or horizontal direction.

[0092] "Prestressed concrete cylinder pipe" (PCCP) refers to a pipe formed from a concrete core, a thin steel cylinder, high-tensile prestressing wires, and a mortar coating. The concrete core is the main structural load-bearing component, and the steel cylinder acts as a waterproof barrier between the concrete layers. The prestressing wires generate a uniform compressive pressure within the core to counteract the tensile stresses within the pipe and are protected from physical damage and external corrosion by the mortar coating.

[0093] "Housing" refers to the casing.

[0094] "Split tube" refers to a conduit having a cut along its length, such as a split metal cylinder, and is preferably formed from an elastic material. The split tube can provide a spring-like expansion of the split tube such that one cut surface is rolled inside the other cut surface (i.e., the outer surface of one cut surface faces the inner surface of the other cut surface).

[0095] "Tube" generally refers to a tubular pipe or conduit.

[0096] As used herein, terms such as "upper", "lower", "between", "upward", "downward", "right", "left", and other terms of relative position or direction refer to the relative position or direction of one component of the valve assembly with respect to another component, or the relative position or direction of the valve assembly with respect to a pipeline or a support surface.

[0097] The term "comprise" and variations such as "comprising" and "comprises" are not intended to exclude other additives, components, integers or steps. The terms "a", "an", "the" and similar references used herein are to be construed as including both singular and plural forms unless the context specifically dictates otherwise. The range described as being "between" two values includes the indicated values.

Claims

1. A replacement valve assembly for a pipe, comprising: (1) A valve body having a right side and a left side, the valve body comprising a right cylinder, a left cylinder, and a central chamber between the right cylinder and the left cylinder, the central chamber, the right cylinder, and the left cylinder being arranged along a longitudinal axis and being in fluid communication to form a fluid passage between a right cylindrical opening of the right cylinder and a left cylindrical opening of the left cylinder, the central chamber comprising a movable valve; a valve body; (2) A right cut-off covering assembly inside the right cylinder, comprising: A right tube having an outer surface, an inner surface, a right side, and a left side; A right elastomeric seal having an outer surface and an inner surface, the outer surface of the right elastomeric seal contacting the inner surface of the right cylinder, and the inner surface of the right elastomeric seal contacting the outer surface of the right tube; a right elastomeric seal; A right inclined surface formed or mechanically connected to the left side of the right tube, the inclined surface having an angle less than 90° and extending into the central chamber; a right cut-off covering assembly; (3) A left cut-off covering assembly inside the left cylinder, comprising: A left tube having an outer surface, an inner surface, a right side, and a left side; A left elastomeric seal having an outer surface and an inner surface, the outer surface of the left elastomeric seal contacting the inner surface of the left cylinder, and the inner surface of the left elastomeric seal contacting the outer surface of the left tube; a left elastomeric seal; A left inclined surface formed or mechanically connected to the right side of the left tube, the inclined surface having an angle less than 90° and extending into the central chamber; a left cut-off covering assembly; comprising: When the valve is moved between a first position and a second position, the right side of the valve contacts the inclined surface of the right tube, and at the same time, the right end of the right cutting cover assembly is pushed out from the right cylindrical opening, and the left side of the valve contacts the inclined surface of the left tube, and the left end of the left cutting cover assembly is pushed out from the left cylindrical opening, whereby the valve assembly fluid-tightly engages with the cut end of the pipe. Valve assembly.

2. The valve assembly according to claim 1, wherein the inclined surface on the right side is formed on the left side of the right tube, and the inclined surface on the left side is formed on the right side of the left tube.

3. At least a first cross brace extends between a first position on the inner surface of the right tube and a second position on the inner surface of the right tube, and the inclined surface on the right side includes a flange extending inward from the first cross brace toward the central chamber. The valve assembly according to claim 1, wherein at least a second cross brace extends between a first position on the inner surface of the left tube and a second position on the inner surface of the left tube, and the inclined surface on the left side includes a flange extending inward from the second cross brace toward the central chamber.

4. The valve assembly according to claim 1, wherein each flange of the first cross brace and the second cross brace is a bent bar or a curved bar.

5. A third cross brace extends between the inner surfaces of the right tube, and includes a flange having an inclined surface extending inward from the third cross brace toward the central chamber. The valve assembly according to claim 1, wherein a fourth cross brace extends between the inner surfaces of the left tube, and includes a flange having an inclined surface extending inward from the fourth cross brace toward the central chamber.

6. The valve assembly according to claim 1, wherein the right tube and the left tube are spring tubes.

7. The valve assembly according to claim 1, further comprising a centering collar for aligning the valve assembly with the pipe end.

8. The valve assembly according to claim 1, wherein the movable valve is a gate valve.

9. A method for replacing a valve within a pipe, comprising: placing a housing so as to engage fluid - tightly with the pipe on the right and left sides of the valve; cutting the pipe on the right and left sides of the valve, thereby creating a right - hand opening and a left - hand opening in the pipe; removing the valve through the housing; advancing a replacement valve assembly into the housing, wherein a cut - covering assembly is disposed within each pipe end of the replacement valve assembly, each cut - covering assembly comprising a cylindrical elastomeric seal, a tube within the seal, and an inclined surface formed within the tube or mechanically connected to the tube, the inclined surface having an angle of less than 90° and extending inwardly towards the central portion of the valve assembly, and the valve assembly further comprising a linear - movement valve for placement between the cut - covering assemblies; aligning the pipe ends of the valve assembly with the right - hand opening and the left - hand opening of the pipe; moving the valve from a first position to a second position, whereby the right side of the valve contacts the inclined surface of the right - hand cut - covering assembly and the right - hand end of the right - hand cut - covering assembly is pushed into the right - hand opening of the pipe, and simultaneously the left side of the valve contacts the inclined surface of the left - hand cut - covering assembly and the left - hand end of the left - hand cut - covering assembly is pushed into the left - hand opening of the pipe, thereby engaging the valve assembly fluid - tightly with the cut ends of the pipe. Claim 10 The method according to claim 9, wherein the inclined surface of the right - hand cut - covering assembly is formed on the left side of the tube of the right - hand cut - covering assembly, and the inclined surface of the left - hand cut - covering assembly is formed on the right side of the tube of the left - hand cut - covering assembly. Claim 11 The method according to claim 9, wherein a first cross - brace extends between the interior of the tube of the right - hand cut - covering assembly, and the right - hand inclined surface comprises a flange extending from the first cross - brace, and a second cross - brace extends between the interior of the tube of the left - hand cut - covering assembly, and the left - hand inclined surface comprises a flange extending from the second cross - brace. Claim 12 The method according to claim 9, wherein the pipe is a prestressed concrete cylinder pipe (PCCP) having a concrete outer layer, an internal metal cylinder, and wires wound around the metal cylinder.

13. The method according to claim 9, wherein the tube of the cutting cover assembly is a spring tube.

14. The method according to claim 9, further comprising the step of adding a centering collar that matches the outer diameter of the pipe to each of the upper portions of the right opening and the left opening of the pipe.

Images