GB2643214A

GB2643214A - Swarfless pipe cutting method

Info

Publication number: GB2643214A
Application number: GB2411543.8A
Authority: GB
Inventors: Francis S Heffernan John
Original assignee: NLB Engineering Ltd
Current assignee: NLB Engineering Ltd
Priority date: 2024-08-06
Filing date: 2024-08-06
Publication date: 2026-02-11
Also published as: GB202411543D0; WO2026032985A1; GB2643214A8

Abstract

A method of swarflessly cutting a pipe comprises the steps of forming a notch (10, fig. 6) in an external surface of a front portion of a wall of the pipe and inserting a pointed blade 51, point first, into the notch in an insertion direction substantially perpendicular to the axial direction of pipe. The blade is moved in the insertion direction through the front portion of the wall of the pipe to shear a kerf into the wall of the pipe, and it is then moved in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from a second portion of the pipe to complete a cut, wherein after completely shearing the first portion of the pipe from the second portion the kerf portion remains connected to the first portion of the pipe. The method also allows for a second notch and a second blade to shear the first portion of the pipe from second and third portions of the pipe.

Description

[0001] SWARFLESS PIPE CUTTING METHOD

[0002] TECHNICAL FIELD

[0003] The present disclosure relates methods of and systems for swarflessly cutting a pipe and methods of and systems for fitting a valve to a pipe using the methods of and systems for swarflessly cutting a pipe.

[0004] BACKGROUND ART

[0005] There are many reasons for fitting a valve into a pipe. Systems are known in the art for fitting a valve or an access port into a pipe. However, these typically introduce contaminant into the pipe from the pipe cutting process, e.g. debris from the cut part of the pipe, commonly known as swarl For some fluid medium conveyed by pipes, it is important that no contaminant is introduced into the pipe. In some cases, e.g. pipework conveying electrical conductors and pressurised with isolation gas such as Sulphur Hexafluoride, metal swarf entering the pipework can cause explosion. Purging the pipes before cutting is often undesirable, impractical or impossible.

[0006] It is an aim of the present invention to at least partially address some of the above problems.

[0007] SUMMARY OF THE INVENTION

[0008] According to a first aspect of the disclosure there is provided a method of swarflessly cutting a pipe, comprising the steps of swarflessly forming first and second notches in an external surface of a front portion of a wall of the pipe, inserting first and second pointed blades, point first, into the respective first and second notches in an insertion direction substantially perpendicular to the axial direction of pipe; moving each blade, in the insertion direction, through the front portion of the wall of the pipe to shear respective first and second kerfs into the wall of the pipe; moving each blade, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from second and third portions of pipe to complete a cut, wherein after completely shearing the first portion of the pipe from the second and third portions of the pipe each respective kerf portion remains connected to the first portion of the pipe.

[0009] According to second aspect of the disclosure there is provided a method of swarflessly cutting a pipe, comprising the steps of swarflessly forming first and second notches in an external surface of a front portion of a wall of the pipe, inserting first and second pointed blades, point first, into the respective first and second notches in an insertion direction substantially perpendicular to the axial direction of pipe, wherein a cutting edge of each blade extends substantially perpendicular to the insertion direction and beyond the edges of the pipe, moving each blade, in the insertion direction, through the front portion of the wall of the pipe to shear respective first and second kerfs into the wall of the pipe, corresponding first and second kerf portions of the wall of the pipe being sheared away from the front wall of the pipe, wherein each kerf portion remains connected to the wall of the pipe at an outer edge where shearing of the front portion of the wall of the pipe has not occurred; arranging first and second support members at an external surface of a back portion of the wall of the pipe, each support member being arranged to support the back portion of the wall of the pipe on only one side of each respective blade, the first and second support members being arranged on respectively opposite sides of the first and second blades in the axial direction of the pipe, each support member comprising a respective shearing surface shaped to correspond to an outer surface of each respective blade in the axial direction of the pipe, each shearing surface being arranged such that as each blade is moved through the back potion of the wall of the pipe, in the insertion direction, a surface of each blade moves along each respective shearing surface; moving each blade, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from second and third portions of pipe to complete a cut, the first portion of the pipe being sheared against each respective shearing surface of each respective support member by each respective blade, the second and third portions of the pipe being respectively supported by each support member; wherein after completely shearing the first portion of the pipe from the second and third portions of the pipe each respective kerf portion remains connected to the first portion of the pipe.

[0010] Optionally, the method further comprises moving each blade, in the insertion direction to move the first portion of the pipe to a position beyond the back portion of the wall of the pipe Optionally, the point of each blade has an angle of substantially 90 degrees.

[0011] Optionally, the cutting edge of each blade is substantially square.

[0012] Optionally, each blade is provided on the same blade member. Optionally, the blade member is substantially cylindrical, the blades being defined by cut-out portions in the blade member and having a substantially cylindrical shape corresponding to the shape of the blade member.

[0013] Optionally, a seal is provided around the cut portions of the pipe to prevent egress of a fluid within the pipe when the pipe is cut. Optionally, the seal is formed by a sealing member configured to surround the pipe, the sealing member comprising the supporting members and an opening through which the blades are inserted for cutting the pipe. Optionally, the sealing member comprises a first bore accommodating the pipe and a second bore perpendicular to the first bore forming the opening through which the blades are inserted for cutting.

[0014] Optionally, the second bore extends through the first bore and comprises a front portion on a front side of the first bore and a back portion on a back side of the first bore, wherein the back portion of the second bore is configured to receive the first portion of the pipe during cutting. Optionally, the first portion of the pipe is moved into the back portion of the bore by the blades during cutting.

[0015] Optionally, the shearing surfaces are formed by respective portions of the back portion of the second bore.

[0016] Optionally, the method further comprises removing the blades from the pipe and inserting a valve into the pipe at the position of the first portion of the pipe. Optionally, the valve forms part of a valve member inserted through the opening in the sealing member, the valve member being connected to the opening of the sealing member, the connection sealing the opening. Optionally, the valve is a plug valve.

[0017] Optionally, the sealing member comprises a sealable conduit connected at one end to the opening Optionally, the sealable conduit is detachably connected to the sealing member.

[0018] Optionally, the sealable conduit comprises a valve for sealing the conduit. Optionally, the valve is a ball valve.

[0019] Optionally, an end of the conduit opposite to the opening is configured to detachably connect to one or more tools for performing the method, including at least a cutting tool comprising the blades. Optionally, the conduit is sealed while one of the one or more tools is being connected to and/or disconnected from the conduit and unsealed, when the tool has been connected to the conduit, to allow a portion of the tool to move through the conduit and the opening of the sealing member. Optionally, the connection between the conduit and the one or more tools forms a seal.

[0020] According to a third aspect of the disclosure there is provided a system for swarflessly cutting a pipe, the system comprising. a sealing member configured to surround the pipe comprising a first bore configured to accommodate the pipe and a second bore perpendicular to the first bore forming an opening in a front portion of the sealing member, the opening providing access to the pipe for cutting, wherein the sealing member is configured to provide a seal around the cut portions of the pipe to prevent egress of a fluid within the pipe when the pipe is cut; a cutting tool configured to be connected to the opening, the cutting tool comprising a blade member comprising first and second pointed blades, the blade member being configured to be inserted through the opening in the sealing member to cut the pipe, wherein a cutting edge of each blade extends substantially perpendicular to the insertion direction and beyond the edges of the pipe; wherein the sealing member comprises first and second support members arranged at an external surface of a back portion of the wall of the pipe, the first and second support members being arranged on respectively opposite sides of the second bore in the axial direction of the pipe and configured to support the back portion of the wall of the pipe, each support member comprising a respective shearing surface formed by a respective portion of the internal surface of the second bore; wherein the first and second blades are configured such that: the first and second pointed blades can be inserted, point first, into respective first and second swarfless notches formed in an external surface of a front portion of a wall of the pipe, in an insertion direction substantially perpendicular to the axial direction of pipe; each blade can be moved, in the insertion direction, through the front portion of the wall of the pipe to shear first and second kerfs into the wall of the pipe, corresponding first and second kerf portions of the wall of the pipe being sheared away from the front wall of the pipe, wherein each kerf portion remains connected to the wall of the pipe at an outer edge where shearing of the front portion of the wall of the pipe has not occurred; and each blade can be moved, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from second and third portions of pipe to complete a cut, the first portion of the pipe being sheared against each respective shearing surface of each respective support member by each respective blade, the second and third portions of the pipe being respectively supported by each support member, and such that after completely shearing the first portion of the pipe from the second and third portions of the pipe each respective kerf portion remains connected to the first portion of the pipe.

[0021] According to a fourth aspect of the disclosure there is provided a kit of part for a systsem for swarflessly cutting a pipe, the kit of parts comprising: a sealing member configured to surround the pipe comprising a first bore configured to accommodate the pipe and a second bore perpendicular to the first bore forming an opening in a front portion of the sealing member, the opening providing access to the pipe for cutting, wherein the sealing member is configured to provide a seal around the cut portions of the pipe to prevent egress of a fluid within the pipe when the pipe is cut; a cutting tool configured to be connected to the opening, the cutting tool comprising a blade member comprising first and second pointed blades, the blade member being configured to be inserted through the opening in the sealing member to cut the pipe, wherein a cutting edge of each blade extends substantially perpendicular to the insertion direction and beyond the edges of the pipe; wherein the sealing member comprises first and second support members arranged at an external surface of a back portion of the wall of the pipe, the first and second support members being arranged on respectively opposite sides of the second bore in the axial direction of the pipe and configured to support the back portion of the wall of the pipe, each support member comprising a respective shearing surface formed by a respective portion of the internal surface of the second bore; wherein the first and second blades are configured such that: the first and second pointed blades can be inserted, point first, into respective first and second swarfless notches formed in an external surface of a front portion of a wall of the pipe, in an insertion direction substantially perpendicular to the axial direction of pipe; each blade can be moved, in the insertion direction, through the front portion of the wall of the pipe to shear first and second kerfs into the wall of the pipe, corresponding first and second kerf portions of the wall of the pipe being sheared away from the front wall of the pipe, wherein each kerf portion remains connected to the wall of the pipe at an outer edge where shearing of the front portion of the wall of the pipe has not occurred; and each blade can be moved, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from second and third portions of pipe to complete a cut, the first portion of the pipe being sheared against each respective shearing surface of each respective support member by each respective blade, the second and third portions of the pipe being respectively supported by each support member, and such that after completely shearing the first portion of the pipe from the second and third portions of the pipe each respective kerf portion remains connected to the first portion of the pipe.

[0022] Optionally, the system or kit of parts further comprises a valve member comprises a valve, configure to be inserted through the opening in the sealing member and into the pipe at the position of the first portion of the pipe after cutting, and connected to the opening of the sealing member, the connection sealing the opening Optionally, the system or kit of parts further comprises a sealable conduit configured to be connected at one end to the opening, wherein an end of the conduit opposite to the opening is configured to detachably connect to one or more tools for performing the cutting, including at least the cutting tool.

[0023] Optionally, the system or kit of parts further comprises a notching tool configured to form the first and second notches in the external surface of a front portion of a wall of the pipe.

[0024] According to a fifth aspect of the disclosure there is provided a method of swarflessly cutting a pipe, comprising the steps of: forming a notch in an external surface of a front portion of a wall of the pipe, inserting a pointed blade, point first, into the notch in an insertion direction substantially perpendicular to the axial direction of pipe, wherein a cutting edge of the blade extends substantially perpendicular to the insertion direction and beyond the edges of the pipe, moving the blade, in the insertion direction, through the front portion of the wall of the pipe to shear a kerf into the wall of the pipe, a corresponding kerf portion of the wall of the pipe being sheared away from the front wall of the pipe, wherein the kerf portion remains connected to the wall of the pipe at an outer edge where shearing of the front portion of the wall of the pipe has not occurred; arranging a support member at an external surface of a back portion of the wall of the pipe, the support member being arranged to support the back portion of the wall of the pipe on only one side of the blade, the support member comprising a shearing surface shaped to correspond to an outer surface of the blade in the axial direction of the pipe, the shearing surface being arranged such that as the blade is moved through the back potion of the wall of the pipe, in the insertion direction, a surface of the blade moves along the shearing surface; moving the blade, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from a second portion of pipe to complete a cut, the first portion of the pipe being sheared against the shearing surface of the support member by the blade, the second portion of the pipe being supported by the support member; wherein, after completely shearing the first portion of the pipe from the second portion of the pipe, the kerf portion remains connected to the first portion of the pipe

[0025] BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Further features of the disclosure will be described below, by way of non-limiting examples and with reference to the accompanying drawings, in which: Fig 1 shows an example sealing member; Fig 2 shows an assembly comprising the sealing member and a conduit; Fig 3 shows an assembly comprising the assembly shown in Fig. 2 and a notching tool; Fig 4 shows the notching tool; Fig 5 shows the notching head of the notching tool in further detail; Fig 6 shows the notching head when forming the notches in the pipe: Fig. 7 shows an assembly comprising the assembly of Fig. 2 and a cutting tool; Fig. 8 shows the cutting tool; Fig. 9 shows a blade member of the cutting tool; Figs. 10 to 13 show different steps of a cutting process performed by the cutting tool; Fig. 14 shows a valve assembly; Fig. 15 shows a valve member of the valve assembly; Fig. 16 shows an assembly comprising the sealing member, sealable conduit and a valve insertion tool; Fig. 17 shows a cross section through the assembly of Fig. 16; arid Fig. 18 is a photograph showing a cut part of a pipe.

[0027] DETAILED DESCRIPTION

[0028] Fig. 1 shows an example sealing member 2 for use in an example method of swarflessly cutting a pipe 1 according to the disclosure. The sealing member 2 may be configured to provide a seal around the cut portions of the pipe 1 to prevent egress of a fluid within the pipe 1 when the pipe 1 is cut.

[0029] As shown in Fig. 1, the sealing member 2 may be configured to surround the pipe 1. In use, the sealing member 2 is positioned to surround a portion of the pipe 1 that is to be cut. As shown, the sealing member 2 may comprise a first bore 20 configured to accommodate the pipe 1, and a second bore 21 substantially perpendicular to the first bore 20. As shown, the second bore 21 comprises an opening 22, in a front portion of the sealing member 2, providing access to the pipe 1 for cutting. The first and second bores 20, 21 are preferably substantially cylindrical. However, the second bore 21 may alternatively have a square or rectangular cross-section.

[0030] As shown in Fig. 1, the first bore 20 extends completely though the sealing member 2. On the other hand, the second bore 21 may extend partially through the sealing member, in other words, the second bore may not be open on a back side of the sealing member 2. As shown, the second bore 21 may extend through the first bore 20 at the back side of the sealing member 2, and comprises a front portion on a front side of the first bore 20 (comprising the opening 22) and a back portion 23 on a back side of the first bore 20.

[0031] As shown in Fig. 1, the back portion 23 of the second bore 21 may extend substantially beyond the first bore 20. The length of the back portion 23 may be at least as long as the width of the pipe in the axial direction of the second bore 21. As described further below, the back portion 23 of the second bore 21 may be configured to receive a cut portion of the pipe 1 during cutting.

[0032] As shown, the second bore 21 may be wider than the first bore 20 and arranged such that the first bore 20 fully intersects the second bore 21. In other words, a gap is provided either side of the first bore 20, and pipe 1 when arranged therein, within the second bore 21. This ensures that the pipe can be completely cut via the second bore.

[0033] As shown in Fig. 1, the sealing member 2 may be formed in two parts, e.g. front and back parts 2A, 2B, configured to be positioned on opposing sides of the pipe 1 and secured together around the pipe. A seal, such an elastomer seal, may be provided between the two parts 2A, 2B and the pipe 1 where they meet. As show, the two parts 2A, 2B may be secured together by bolts 2C, or any other suitable securing means.

[0034] Fig. 2 shows an assembly comprising the sealing member 2 of Fig. 1 and an example sealable conduit 3, for use in the example method of swarflessly cutting a pipe 1 according to the disclosure. The sealable conduit 3 is configured to be connected at a first end to the opening 22 of the sealing member 2. The conduit 3 may comprise a linear, elongate body comprising a bore 30 therethrough configured to communicate with the opening 22 and the second bore 21 of the sealing member 2. A shown in Fig. 2, the conduit 3 may comprise a valve 31, e.g. a ball valve, for selectively sealing the conduit 3, e.g. the bore thereof As shown in Fig. 2, the conduit 3 may comprise a first connecting member 32 at the first end configured to connect to the sealing member 2. As shown in Fig. I, the sealing member 2 may comprise a connecting member 24 arranged at the opening configured to engage with the connecting member 32 of the conduit 3 (as well as other parts, as described further below). As shown, the connecting member 32 of the conduit 3 may comprise a threaded nut configured to engage with a corresponding threaded flange of the connecting member 24 of the sealing member 2. The connection between the conduit 3 and the sealing member 2 may form a seal.

[0035] As shown in Fig. 2, the conduit, 3 may comprise a second connecting member 33 at the first end configured to connect to one or more tools. As shown, the second connecting member 33 of the conduit 3 may comprise a threaded nut configured to engage with a corresponding threaded portion of a tool.

[0036] Fig. 3 shows an assembly comprising the assembly shown in Fig. 2 and a notching tool 4, for use in the example method of swarflessly cutting a pipe t according to the disclosure. The notching tool 4 is configured to form first and second notches in an external surface of a front portion of a wall of the pipe 1, as described further below.

[0037] Fig. 4 shows the notching tool 4 alone. As shown, the notching tool 4 may comprise a collar member 40 comprising a bore therethrough and a linear elongate shaft 41 configured to pass through the collar member 40 and move, e.g. slidably, within the collar member 40. As shown, the shaft 41 and the bore in the collar member may be substantially cylindrical. The shaft 41 and the bore may form a seal. The notching tool 4 may further comprise a notching head 42 at a first end of the shaft 41. The notching tool 4 may further comprise a handle 43, e.g. a wheel, at a second end of the shaft 21, for moving the shaft linearly and rotationally relative to the collar member 40.

[0038] As shown in Fig. 3, the notching tool 4 is configured to be connected to the conduit 3, at the second end thereof As shown, the collar member 40 of the notching tool 4 may be configured to connect to the conduit 3. As shown in Fig. 5, the notching tool 4, e.g. specifically the collar member 40, may comprise a connecting member 44 configured to engage with the second connecting member 33 of the conduit 3. As shown, the connecting member 44 of the notching tool may comprise a threaded flange. The connection between the conduit 3 and the notching tool 4 may form a seal.

[0039] Fig. 5 shows the notching head 43 in further detail. As shown, the notching head 43 may comprise a cylindrical body 45 and two cutting wheels 46 on diametrically opposite sides of the cylindrical body 45. The cylindrical body 45 may be connected to, or form part of, the shaft 41. An axis through the cutting wheels 46 is perpendicular to the axis of the cylindrical body 45, i.e. in a radial direction of the cylindrical body 45. The cutting wheels 46 extend beyond an end of the cylindrical body 45 in the axial direction to enable them to engage with an external surface of the pipe 1. As shown, the cutting wheels 46 may comprise a bevelled cutting edge along their circumference.

[0040] Fig. 6 shows the notching head 43 when forming the notches in the pipe 1. As shown, the cutting wheels 45 are arranged to form first and second notches 10 in the pipe 1. The first and second notches 10 are separated in the axial direction of the pipe 1, e.g. top and bottom in Fig. 7. The notching head 43 is inserted through the opening 22 of the sealing member 2 to exert pressure on the pipe through the cutting wheels 45 and rotated, e.g. back and forth, to form the notches. The cutting wheels 46 may be configured to shear through surface of the pipe 1, without producing any debris i.e. swarflessly. The notches 10 may not penetrate the pipe 1.

[0041] After forming the notches 10 the notching head 43 is retracted from the opening and the notching tool 4 disconnected from the conduit 3. Optionally, the conduit may be sealed by the valve prior to disconnecting the notching tool 4.

[0042] Fig. 7 shows an assembly comprising the assembly of Fig. 2 and a cutting tool 5, for use in the example method of swarflessly cutting a pipe 1 according to the disclosure. The cutting tool is configured to swarflessly cut the pipe 1, e.g. after preparation by the notching tool 4.

[0043] Fig. 8 shows the cutting tool 5 alone. As shown, the cutting tool 5 may comprise a blade member 50 comprising first and second pointed blades 51. As shown, the blade member 50 may be connected to, or form part of a first end of a shaft 52. The shaft 52 may form part of a piston rod, together with a cylinder barrel 53 forming a ram, e.g. a hydraulic ram.

[0044] Fig. 9 shows the blade member in further detail. As shown, the blade member 50 may generally have a substantially cylindrical shape. In other examples, in which the second ore 21 has a square or rectangular cross-section, the blade member 50 may have a corresponding square or rectangular cross-section. As shown, the blades 51 may be defined by cut-out portions in the blade member. The blades 51 may have a shape corresponding to the shape of the blade member 51e.g. substantially cylindrical. As shown, the blades 51 may be arranged at diametrically opposite sides of the blade member 50. As shown, the cutting edge of each blade 51 may be substantially square, e.g. as opposed to bevelled. The cutting edge may have a thickness of from 1 mm to 2 mm, for example, preferably around 1.6 mm. As shown, the point of each blade may have an angle of from 80 degrees to 100 degrees, preferably around 90 degrees.

[0045] The blade member 50 and blades 51 may be formed from steel. The pipe 1 may be formed from carbon steel, stainless steel, cast iron, copper or plastic.

[0046] As shown in Fig. 7, the cutting tool 5 is configured to be connected to the conduit 3, at the second end thereof As shown, the cylinder barrel 52 of the cutting tool 5 may be configured to connect to the conduit 3. As shown in Fig. 9, the cutting tool 5, e.g. specifically the cylinder barrel 52, may comprise a connecting member 54 configured to engage with the second connecting member 33 of the conduit 3. As shown, the connecting member 54 of the cutting tool 5 may comprise a threaded flange. The connection between the conduit 3 and the notching tool 4 may form a seal.

[0047] Figs. 10 to 13 show different steps of a cutting process performed by the cutting tool 5. Each of the figures shows a cross-section through the assembly of Fig. 9.

[0048] A first step, shown in Fig. 10, comprises inserting the first and second pointed blades, point first, into the respective first and second notches in a direction substantially perpendicular to the axial direction of pipe, (i.e. the axial direction of the second bore 42 of the sealing member 4). The cutting edge of each blade 51 extends substantially perpendicular to the insertion direction and beyond the edges of the pipe 1. The notches prevent the pipe collapsing in a second step.

[0049] A second step, shown in Fig. 11, comprises moving each blade 51, in the insertion direction, through the front portion of the wall of the pipe Ito shear respective first and second kerfs into the wall of the pipe 1. In this step, corresponding first and second kerf portions of the wall of the pipe 1 are sheared away from the front wall of the pipe 1. Each kerf portion remains connected to the wall of the pipe 1 at an outer edge where shearing of the front portion of the wall of the pipe has not occurred.

[0050] A third step, shown in Fig. 12, comprises moving each blade 51, in the insertion direction, through the back portion of the wall of the pipe I. As shown, a first portion of the pipe 1 that is cut by the blades 51 (this cut away portion is referred to as a coupon) is sheared against a back portion of the sealing member 2. The shearing is enabled by the mutual configuration of the sealing member 2 and the blade member 50.

[0051] As shown in Fig. 12, the sealing member 2 may comprise first and second support members 25 configured to be arranged at an external surface of a back portion of the wall of the pipe 1.

[0052] The first and second support members 25 may form a back part of the first bore 20 of the sealing member 2, for example. The first and second support members 25 may be provided on opposite sides of the second bore 21 in the axial direction of the first bore 20. The first and second support members 25 may comprise respective first and second shearing surfaces 26 corresponding to a portion of the surface of the back portion of the second bore 21. The first and second shearing surfaces 26 are configured to shear against respective outer surfaces of the blades 51. Accordingly, an outer diameter of the cylindrical blade member 50 may be substantially the same as the diameter of the second bore 21.

[0053] As shown, each support member 25 is configured to support the back portion of the wall of the pipe 1 on only one side of each respective blade 51 during cutting. The first and second support members 25 are arranged on respectively opposite sides of the first and second blades in the axial direction of the pipe 1 during cutting. The first and second shearing surfaces 26 are shaped to correspond to an outer surface (in the axial direction of the pipe 1) of each respective blade 51. Each shearing surface 25 is arranged such that as each blade 51 is moved through the back portion of the wall of the pipe 1, in the insertion direction, the outer surface of each blade 51 moves, e.g. slidably, along each respective shearing surface 26, in a shearing motion.

[0054] As shown in Fig. 13, each blade 51 is moved completely though the back portion of the wall of the pipe 1 to completely shear a first (central) portion of the pipe 1, the coupon, away from second and third (peripheral) portions of pipe 1 to complete the cut. By the combination of a first kerf generating part of the cut and a second shearing part of the cut, after completely shearing the coupon from the second and third portions of the pipe 1, each kerf portion remains connected to the coupon. Accordingly, a swarfless cut is achieved Fig. 13 also shows a fourth step comprising continuing to move each blade 51, in the insertion direction, to move the coupon to a position beyond the back portion of the wall of the pipe 1.

[0055] As shown, the coupon is moved into a back portion 23 of the second bore 21. The coupon may remain in the back portion 23 of the second bore 21 after cutting.

[0056] After cutting the blades 51 are retracted from the opening and the cutting tool 5 disconnected from the conduit 3. Preferably, the conduit 3 may be sealed by the valve prior to disconnecting the cutting tool 5.

[0057] The method of swarflessly cutting a pipe 1 described above may form part of a method of fitting a valve into the pipe 1. The valve may form part of a valve assembly, together with the sealing member 2. To form the valve assembly, the sealing member 2 may be arranged around the pipe 1, as described above, a coupon cut out, as described above and a valve inserted into the pipe 1 at the position of the coupon.

[0058] An example valve assembly is shown in Fig. 14. As shown in Fig. 14, the valve may form part of a valve member 6 inserted through the opening 22 in the sealing member 2. As shown the valve member 6 may be connected to the opening 22 of the sealing member 2. The connection may seal the opening 22.

[0059] Fig. 15 shows the valve member 6 alone. As shown, the valve member 6 may comprise a valve 60 (e.g. as plug valve as shown) and a connecting member 61 configured to connect to the sealing member 2. As shown, the connecting member 61 may comprise a threaded portion on an outer circumferential surface of the valve member 6. The connecting member 61 may be configured to engage with a corresponding threaded in portion of the opening 20 of the sealing member on an inner surface of the front portion of the second bore 21 of the sealing member 2.

[0060] Fig. 16 shows an assembly comprising the sealing member 2, sealable conduit 3 and a valve insertion tool 7 for inserting the valve member 6. Fig. 17 shows a cross section through the assembly of Fig. 16. As shown, the valve insertion tool 7 may comprise a linear elongate housing 70 comprising a connecting member 71 at a first end thereof for connecting the valve insertion tool to the conduit 2, e.g. via the second connecting member thereof As shown, the connecting member 71 may comprise a threaded portion. The connection may form a seal.

[0061] The valve insertion tool 7 may be connected to the conduit 3 when the conduit 3 is sealed.

[0062] As shown in Fig. 17, the housing 70 may comprise an end cap 72 at a second end thereof As shown the end cap 72 may comprise a bore for accommodating a shaft 73 comprising a head 74 at a first end thereof configured to hold and manipulate the valve assembly 6. The shaft 73 may be configured to move linearly and rotationally in the bore. The shaft 73 form a seal with the bore.

[0063] To connect the valve assembly 6 to the sealing member, the shaft 73 of the valve insertion tool 7 is extended to insert the valve assembly 6 into the opening 22 in the sealing member 2 and rotated to engage the mutual threaded portions to connect the valve assembly 6 to the sealing member 2. The shaft 73 is then retracted and the valve insertion tool 7 and the conduit 3 are disconnected from the sealing member 2.

[0064] According to the above described methods, a pipe can be cut without introducing any swarf into the pipe, and a valve fitted to the pipe. Further, this can be performed while fluid (liquid or gas) flows through pipe under pressure.

[0065] Fig. 18 is a photograph showing a cut part of a pipe cut according to the above method. The sheared back side of the pipe is shown at the bottom and the kerfed part at the top. The kerf portion is locating in the middle of the pipe and remains attached to the rest of the cut portion of the pipe.

[0066] It should be understood that the above-described examples are for illustrative purposes only and the invention may otherwise be implemented without departing from the spirit or scope of the invention as defined by the appended claims.

Claims

1. CLAIMS

2. A method of swarflessly cutting a pipe, comprising the steps of: swarflessly forming first and second notches in an external surface of a front portion of a wall of the pipe, inserting first and second pointed blades, point first, into the respective first and second notches in an insertion direction substantially perpendicular to the axial direction of pipe, wherein a cutting edge of each blade extends substantially perpendicular to the insertion direction and beyond the edges of the pipe; moving each blade, in the insertion direction, through the front portion of the wall of the pipe to shear respective first and second kerfs into the wall of the pipe, corresponding first and second kerf portions of the wall of the pipe being sheared away from the front wall of the pipe, wherein each kerf portion remains connected to the wall of the pipe at an outer edge where shearing of the front portion of the wall of the pipe has not occurred; arranging first and second support members at an external surface of a back portion of the wall of the pipe, each support member being arranged to support the back portion of the wall of the pipe on only one side of each respective blade, the first and second support members being arranged on respectively opposite sides of the first and second blades in the axial direction of the pipe, each support member comprising a respective shearing surface shaped to correspond to an outer surface of each respective blade in the axial direction of the pipe, each shearing surface being arranged such that as each blade is moved through the back potion of the wall of the pipe, in the insertion direction, a surface of each blade moves along each respective shearing surface; moving each blade, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from second and third portions of pipe to complete a cut, the first portion of the pipe being sheared against each respective shearing surface of each respective support member by each respective blade, the second and third portions of the pipe being respectively supported by each support member, wherein after completely shearing the first portion of the pipe from the second and third portions of the pipe each respective kerf portion remains connected to the first portion of the Pipe 2. The method of claim I, further comprising moving each blade, in the insertion direction to move the first portion of the pipe to a position beyond the back portion of the wall of the pipe.

3. 3 The method of any preceding claim, wherein the point of each blade has an angle of substantially 90 degrees.

4. The method of any preceding claim, wherein the cutting edge of each blade is substantially square.

5. The method of any preceding claim, wherein each blade is provided on the same blade member.

6. The method any claim 5, wherein the blade member is substantially cylindrical, the blades being defined by cut-out portions in the blade member and having a substantially cylindrical shape corresponding to the shape of the blade member.

7. The method of any preceding claim, wherein a seal is provided around the cut portions of the pipe to prevent egress of a fluid within the pipe when the pipe is cut.

8. The method of claim 7, wherein the seal is formed by a sealing member configured to surround the pipe, the sealing member comprising the supporting members and an opening through which the blades are inserted for cutting the pipe.

9. The method of claim 8, wherein the sealing member comprises a first bore accommodating the pipe and a second bore perpendicular to the first bore forming the opening through which the blades are inserted for cutting.

10. The method of claim 9, wherein the second bore extends through the first bore and comprises a front portion on a front side of the first bore and a back portion on a back side of the first bore, wherein the back portion of the second bore is configured to receive the first portion of the pipe during cutting.

11. The method of claim 10, wherein the first portion of the pipe is moved into the back portion of the bore by the blades during cutting.

12. The method of claim 10 or 11, wherein the shearing surfaces are formed by respective portions of the back portion of the second bore

13. The method of any preceding claim, further comprising removing the blades from the pipe and inserting a valve into the pipe at the position of the first portion of the pipe.

14. The method of claim 13, when dependent on any one of claims 8 to 12, wherein the valve forms part of a valve member inserted through the opening in the sealing member, the valve member being connected to the opening of the sealing member, the connection sealing the opening.

15 The method of claim 13 or 14, wherein the valve is a plug valve.

16 The method of any one of claims 8 to 15, wherein the sealing member comprises a sealable conduit connected at one end to the opening.

17. The method of claim 16, wherein the sealable conduit is detachably connected to the sealing member.

18. The method of claim 16 or 17, wherein the sealable conduit comprises a valve for sealing the conduit.

19. The method of claim 18, wherein the valve is a ball valve.

20. The method of any one of claims 16 to 19, wherein an end of the conduit opposite to the opening is configured to detachably connect to one or more tools for performing the method, including at least a cutting tool comprising the blades.

21. The method of claim 20, wherein the conduit is sealed while one of the one or more tools is being connected to and/or disconnected from the conduit and unsealed, when the tool has been connected to the conduit, to allow a portion of the tool to move through the conduit and the opening of the sealing member.

22. The method of any one of claims 20 to 21, wherein the connection between the conduit and the one or more tools forms a seal

23. A system, or kit of parts for a system, for swarflessly cutting a pipe, the system or kit of parts comprising: a sealing member configured to surround the pipe comprising a first bore configured to accommodate the pipe and a second bore perpendicular to the first bore forming an opening in a front portion of the sealing member, the opening providing access to the pipe for cutting, wherein the sealing member is configured to provide a seal around the cut portions of the pipe to prevent egress of a fluid within the pipe when the pipe is cut, a cutting tool configured to be connected to the opening, the cutting tool comprising a blade member comprising first and second pointed blades, the blade member being configured to be inserted through the opening in the sealing member to cut the pipe, wherein a cutting edge of each blade extends substantially perpendicular to the insertion direction and beyond the edges of the pipe; wherein the sealing member comprises first and second support members arranged at an external surface of a back portion of the wall of the pipe, the first and second support members being arranged on respectively opposite sides of the second bore in the axial direction of the pipe and configured to support the back portion of the wall of the pipe, each support member comprising a respective shearing surface formed by a respective portion of the internal surface of the second bore; wherein the first and second blades are configured such that.the first and second pointed blades can be inserted, point first, into respective first and second swarfless notches formed in an external surface of a front portion of a wall of the pipe, in an insertion direction substantially perpendicular to the axial direction of pipe; each blade can be moved, in the insertion direction, through the front portion of the wall of the pipe to shear first and second kerfs into the wall of the pipe, corresponding first and second kerf portions of the wall of the pipe being sheared away from the front wall of the pipe, wherein each kerf portion remains connected to the wall of the pipe at an outer edge where shearing of the front portion of the wall of the pipe has not occurred; and each blade can be moved, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from second and third portions of pipe to complete a cut, the first portion of the pipe being sheared against each respective shearing surface of each respective support member by each respective blade, the second and third portions of the pipe being respectively supported by each support member, and such that after completely shearing the first portion of the pipe from the second and third portions of the pipe each respective kerf portion remains connected to the first portion of the pipe.

24. The system or kit of parts of claim 23, further comprising a valve member comprising a valve, configure to be inserted through the opening in the sealing member and into the pipe at the position of the first portion of the pipe after cutting, and connected to the opening of the sealing member, the connection sealing the opening.

25. The system or kit of parts of claim 23 or 24, further comprising a sealable conduit configured to be connected at one end to the opening, wherein an end of the conduit opposite to the opening is configured to detachably connect to one or more tools for performing the cutting, including at least the cutting tool.

26. The system or kit of parts of any one of claims 23 to 25, further comprising a notching tool configured to form the first and second notches in the external surface of a front portion of a wall of the pipe.

27. A method of swarflessly cutting a pipe, comprising the steps of: forming a notch in an external surface of a front portion of a wall of the pipe; inserting a pointed blade, point first, into the notch in an insertion direction substantially perpendicular to the axial direction of pipe, wherein a cutting edge of the blade extends substantially perpendicular to the insertion direction and beyond the edges of the pipe; moving the blade, in the insertion direction, through the front portion of the wall of the pipe to shear a kerf into the wall of the pipe, a corresponding kerf portion of the wall of the pipe being sheared away from the front wall of the pipe, wherein the kerf portion remains connected to the wall of the pipe at an outer edge where shearing of the front portion of the wall of the pipe has not occurred; arranging a support member at an external surface of a back portion of the wall of the pipe, the support member being arranged to support the back portion of the wall of the pipe on only one side of the blade, the support member comprising a shearing surface shaped to correspond to an outer surface of the blade in the axial direction of the pipe, the shearing surface being arranged such that as the blade is moved through the back potion of the wall of the pipe, in the insertion direction, a surface of the blade moves along the shearing surface; moving the blade, in the insertion direction, through the back portion of the wall of the pipe to completely shear a first portion of the pipe away from a second portion of pipe to complete a cut, the first portion of the pipe being sheared against the shearing surface of the support member by the blade, the second portion of the pipe being supported by the support member, wherein, after completely shearing the first portion of the pipe from the second portion of the pipe, the kerf portion remains connected to the first portion of the pipe.