WO2008035104A1 - Appareil et procédé pour raccorder un tube doublé - Google Patents

Appareil et procédé pour raccorder un tube doublé Download PDF

Info

Publication number
WO2008035104A1
WO2008035104A1 PCT/GB2007/003610 GB2007003610W WO2008035104A1 WO 2008035104 A1 WO2008035104 A1 WO 2008035104A1 GB 2007003610 W GB2007003610 W GB 2007003610W WO 2008035104 A1 WO2008035104 A1 WO 2008035104A1
Authority
WO
WIPO (PCT)
Prior art keywords
cipp
pipe
seal
lined pipe
lined
Prior art date
Application number
PCT/GB2007/003610
Other languages
English (en)
Inventor
Stephen John Taylor
Original Assignee
Planned Maintenance (Pennine) Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Planned Maintenance (Pennine) Limited filed Critical Planned Maintenance (Pennine) Limited
Publication of WO2008035104A1 publication Critical patent/WO2008035104A1/fr
Priority to GB0904111A priority Critical patent/GB2454157A/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L21/00—Joints with sleeve or socket
    • F16L21/02—Joints with sleeve or socket with elastic sealing rings between pipe and sleeve or between pipe and socket, e.g. with rolling or other prefabricated profiled rings
    • F16L21/04—Joints with sleeve or socket with elastic sealing rings between pipe and sleeve or between pipe and socket, e.g. with rolling or other prefabricated profiled rings in which sealing rings are compressed by axially-movable members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L23/00—Flanged joints
    • F16L23/02—Flanged joints the flanges being connected by members tensioned axially

Definitions

  • the present invention relates to an apparatus and method for use in forming a joint, in particular for forming a joint with a pipe which contains a cured-in- place lining.
  • the invention is suitable for use in pipes which are used to transfer any type of fluid, for example water, oil or natural gas, at low or high pressures, for example up to 25 Bar.
  • Ductile iron sections of pipeline have eroded much more quickly than the cast iron sections and following a recent explosion resulting from this erosion, the Health and Safety Executive recommended that all ductile iron be removed from pipelines located within 30 metres of any property.
  • a cast iron section is simply bolted to a ductile iron section, it is a relatively simple operation to remove the ductile iron section and replace it with, for example, a polyethylene pipe which bolts onto the remaining cast iron section.
  • problems arise when the pipes in question are CIPP-lined.
  • a CIPP (cured in place pipe) lining is well known to those skilled in the art.
  • a long, flexible lining tube is drawn through the pipe. Air or water under pressure is then fed into the tube which causes it to fit tightly to the wall of the pipe.
  • the liner comprises on its outer surface when fitted an epoxy resin which is thus distributed between the liner and the internal surface of the pipe. Once the liner is in place, hot water or air is circulated through the pipe. This cures the thermo- setting epoxy resin and secures the pipe in place.
  • a continuous lining may be applied throughout the interior of a pipeline thus lining with a single liner adjoining sections made from cast iron and ductile iron.
  • the joint may be internally sealed using any suitable method as will be known by those skilled in the art.
  • a preferred method of sealing such a joint is by the use of a seal such as that sold under the trade mark AMEX-10, produced by Meyer and John of Hamburg, Germany and supplied in the UK by PMP Limited of Lancashire. Details of the AMEX-10 seal can be found at www . pmp-ltd.co.uk.
  • the AMEX-10 seal is typically used to fit pipes having a diameter of at least 24 inches and into which an engineer is able to climb if necessary.
  • a typical AMEX-10 seal is shown in Figure IA in which the seal is located across the joint of pipes 1 and 2.
  • Pipe 2 is shown in a cut away view so that the seal can be clearly seen.
  • a cross section of the seal and the joint along the line A-A' is shown in Figure IB.
  • the AMEX-10 seal comprises a tube 3 of substantially cylindrical cross-section. It is made from a rubber material, for example EPDM (ethylene propylene diene monomer) rubber or NBR (nitrile rubber) .
  • each end of the internal surface of the rubber seal is provided with an annular recess 6 designed to receive a stainless steel retaining ring 7. Two such rings are provided. Each is fitted in place loosely at first, and then hydraulically expanded and secured with stainless steel retaining wedges.
  • the underside of each end of the rubber ring seal is provided with three double sealing ribs 8 between inner and outer sealing lips 9 and 10.
  • the engineer applying the seal will repeatedly hit the retaining ring once in position, for example using a metal rod. This vibration ensures that the rubber forms a strong seal with the pipe surface.
  • the effectiveness of the seal can be tested via test nipple 11. Soap solution is applied to the edge of the seal and nitrogen is delivered to the test nipple. The presence of a leak is indicated if bubbling is seen around the edge of the seal.
  • Gas pipes may have a diameter of for example 8", 12", 16", 18", 20" or 21", although pipes of larger diameter are known.
  • the method of sealing a joint using an AMEX- 10 seal as shown in Figures IA and IB is not suitable for completely sealing a CIPP-lined section of pipe to a section of new replacement pipe.
  • Figure 2 shows a problem which can arise when an AMEX- 10 seal 20 is used to seal the joint of a CIPP lined pipe 23 to an ordinary pipe 21.
  • the seal 20 is held in place by steel retaining rings 25.
  • Pipe 23 is provided with a CIPP lining 22. If there is a tear in the lining at a different location, which could be distant from the joint, gas could enter the space behind the CIPP lining at 24. Thus gas could travel along the pipe behind the lining and would be able to escape via the joint at B, behind the seal. This leakage would be both costly and potentially dangerous.
  • the AMEX-10 seal provides an effective internal seal, external leakage is still possible when it is used with a CIPP-lined pipe.
  • an apparatus for providing an outer seal around a CIPP-lined pipe comprising a tubular body, the internal dimension of which is slightly larger than the external dimension of the CIPP-lined pipe, the tubular body being adapted at one end to be connected to a section of replacement pipe and at the other end to receive a CIPP-lined pipe so as to form an airtight seal around the outer surface of said CIPP-lined pipe.
  • the tubular body comprises a cylindrical body.
  • the apparatus for providing an outer seal may be made from any suitable material.
  • Preferred materials are stainless steel and especially, mild steel.
  • the material must be strong, tough, non brittle, durable and corrosion resistant or provided with a corrosion resistant coating.
  • the apparatus may be made from a single casting or may be manufactured from a plurality of pieces welded together.
  • a positioning means which ensures that the CIPP-lined pipe is correctly positioned within the apparatus.
  • This typically comprises a projection which extends into the internal cavity and prevents the pipe from being pushed through the apparatus.
  • the positioning means comprises an annular projection which extends into the internal cavity of the cylindrical body.
  • the positioning means may comprise an inner cylinder which is coaxial with the outer cylindrical body and of shorter length.
  • the internal diameter of the inner cylinder is substantially identical to the internal diameter of the CIPP-lined pipe.
  • the CIPP-lined pipe is inserted into the apparatus until it reaches the internal edge of the inner cylinder.
  • the other end of the inner cylinder is suitably appended to the main outer cylindrical body of the apparatus at the end adapted to be connected to a section of replacement pipe.
  • Extending from the end to be connected to the section of replacement pipe there is preferably provided an outer flange which extends substantially perpendicularly from the wall of the cylinder.
  • the flange is preferably provided with a number of apertures which enable a new section of replacement pipe having a corresponding flange to be bolted thereto. These apertures are preferably equally spaced about the flange.
  • the flange is provided with at least 3 such apertures, preferably at least 6 apertures. It may comprise 8 or more apertures, for example between 8 and 20 apertures, for example 10 or 12 apertures.
  • the flange may be a fixed flange able to connect to a replacement pipe having a complementary flange or it may be provided with a multi-flange system suitable for connection to a plurality of different flanges. Preferably it is a fixed flange.
  • the end of the apparatus adapted to receive the CIPP lined pipe preferably tapers outwardly so that it may accommodate, in use, a sealing ring between the outer surface of the CIPP lined pipe and the inner surface of the' apparatus .
  • the apparatus may be provided with a further flange in the region immediately below the tapered end of the cylinder, said second flange being adapted to be releasably connected to a further external annular member, such that in use, the connection between the flange and the external annular member can be adjusted to effect a seal around the external edge of a CIPP-lined pipe positioned within the apparatus.
  • the second flange is provided with a plurality of apertures which can be aligned with a plurality of apertures on the external annular member so that a system of nuts and bolts can be used to tighten and loosen the engagement of the apparatus with the pipe.
  • the second flange preferably comprises at least 3 apertures, preferably at least 4, for example at least 6. It may suitably comprise between 6 and 16 apertures, for example 8 or 10 apertures.
  • the external annular member may be provided with the same number of apertures as the second flange.
  • the external annular member is preferably loosely connected to the second flange by a plurality of bolts so that it is possible for a pipe to be positioned within the core of the apparatus.
  • a pipe Preferably between 4 and 12, for example 6 to 10 bolts are used.
  • a rubber seal may also be loosely placed in the interior of the apparatus in preparation for use.
  • the apparatus is preferably provided with one or more means for positioning the main cylindrical body centrally around a pipe.
  • These means suitably comprise a plurality of bolts spaced around the cylindrical surface of the apparatus such that each bolt extends tangentially through the surface of the apparatus and can be screwed into the apparatus such that the tip of the bolt contacts the outer surface of a pipe positioned within the apparatus.
  • Adjustment of the different bolts enables the relative position of the pipe and the apparatus to be adjusted so that the pipe lies substantially centrally within the apparatus.
  • Each of the bolts is suitably located within a housing.
  • the housing may comprise a small cylindrical body extending from the surface of the apparatus.
  • the housing is preferably sealed with a cap which must be removed in order to access the bolt.
  • a suitable cap may be a threaded cap used with a Dowty washer to ensure an airtight seal.
  • the apparatus may comprise a further housing, for example a further cylindrical housing having an airtight seal.
  • a gas for example, air or nitrogen
  • kits for use in forming a seal with a CIPP-lined pipe comprising an apparatus for providing an outer seal as defined in accordance with the first aspect and an apparatus for providing an inner seal.
  • the present invention provides a kit which enables a user to form both an internal and an external seal around a CIPP-lined pipe.
  • the apparatus for providing an inner seal comprises a rubber tube of substantially cylindrical cross-section, two retaining rings and two corresponding retaining wedges to hold the rings in place.
  • the apparatus for providing an inner seal comprises a rubber tube of substantially cylindrical cross-section, two retaining rings and two corresponding retaining wedges to hold the rings in place.
  • grooves In the region of the outer edges of the internal surface of the rubber tube there are provided grooves to accommodate the retaining rings.
  • sealing ribs are located in the region of the outer edges of the external surface, on the opposite side of the tube to the grooves for accommodating the retaining rings.
  • sealing ribs are located at each end a region comprising one or more sealing ribs, for example 2, 3 or 4 sealing ribs.
  • inner and outer lips are preferably provided around each of these regions of sealing ribs, the outer lips provided at the edges of the seal.
  • the seal may be made from any suitable material. However, preferred materials are EPDM (ethylene propylene diene monomer) or NBR (nitrile rubber) .
  • EPDM ethylene propylene diene monomer
  • NBR nitrile rubber
  • the retaining rings and retaining wedges are preferably of stainless steel.
  • the apparatus for providing an inner seal around said joint is preferably a seal of similar construction to the seal known under the trade mark AMEX-10.
  • a method of providing an outer seal around a CIPP-lined pipe comprising providing an apparatus comprising a tubular body, the internal dimension of which is slightly larger than the external dimension of the CIPP-lined pipe, the method comprising connecting one end of the tubular body to a section of replacement pipe and connecting the other end of the tubular body to a CIPP-lined pipe so as to form an airtight seal around the outer surface of said CIPP-lined pipe.
  • the third aspect of the invention further provides a method of forming a seal with a CIPP-lined pipe, the method comprising:
  • the present invention provides a method of forming both an internal and an external seal around a CIPP-lined pipe.
  • the present invention also provides a method of providing a secure seal of a rubber sealing tube to the internal surface of the pipe by expanding a retaining ring and retaining wedge using a hydraulic ram attached to a vibrating machine, thus applying continuous vibrations to the rubber as the ring is expanded.
  • the vibrating machine vibrates at a frequency of 1000 cycles per minute.
  • a suitable vibrating machine is a K-series ball vibrator available from K Supplies Limited of
  • a fourth aspect of the present invention there is provided the use of the apparatus of the first aspect or a kit of the second aspect to form a seal around a CIPP-lined pipe.
  • the apparatus, kit and method of present invention may be used to form a joint to CIPP-lined pipes of all sizes. However, it is particularly useful for sealing a joint to pipes having a diameter of less than 30", for example less than 24".
  • the invention may be used on pipes carrying any fluid but is especially suitable for pipes carrying natural gas (methane) .
  • the apparatus, kit and method of the present invention are typically used to form a joint between two pipes having the same internal diameter.
  • figure 3 shows an apparatus for forming an outer seal in accordance with the first aspect of the invention
  • figure 4 shows a cross-section of the apparatus of figure 3 along the line B-B' ;
  • figure 5 shows a perspective view of an apparatus for forming an outer seal in which a rubber sealing ring and an external annular member are placed in position so that the apparatus is ready to use;
  • figure 6 is a perspective view of the side of the apparatus of figure 5;
  • figure 7 is a cross-sectional view of a bolt located in a cylindrical housing
  • figure 8 is a cross-sectional view of an additional housing provided to allow the seal to be tested; and figure 9 shows a rubber sealing ring for use with the invention.
  • the apparatus will be described as if sitting in a vertical position as shown in the figures. However, it will be appreciated that in use when joining a pipe, the apparatus may be located in a substantially horizontal position.
  • the apparatus comprises an outer cylindrical body 30 which is flared at its upper end 31.
  • the body At its lower end the body comprises an outer flange 32 having a plurality of apertures 33 spaced around the flange.
  • the flange extends slightly into the internal cavity of the outer cylindrical body to join an inner cylinder 34, the top of which extends to just under half of the height of the outer cylindrical body.
  • a further flange 35 In the region near to the top of the outer body, but below the flared region there is provided a further flange 35 extending from the outer surface of the body and having a plurality of apertures 36.
  • Figures 5 and 6 show the apparatus ready to be fitted to a pipe in which an external annular member 42 and a rubber sealing ring 46 have been roughly positioned in place.
  • the external annular member 42 comprises an outer flange 43 of similar external diameter to flange 35 and a depending internal skirt 44, which is shaped to fit just outside the outer tip of the outer upper edge of the main cylindrical body.
  • Flange 43 is provided with a plurality of apertures which are aligned with the apertures on 46 on flange 35 of the main cylindrical body.
  • a plurality of nuts and bolts 45 are used to loosely attach flanges 35 and 43.
  • a rubber ring 46 which is shaped to fit into the flared internal surface of the outer cylindrical body. This rubber ring is shown in perspective view in figure 9.
  • Figure 7 shows a cross-section through the cylindrical housing 38, which is welded to the outer surface of main cylindrical body 30.
  • the surface of the main cylindrical body 30 comprises a threaded aperture so that bolt 37 may be screwed in and out of the body.
  • Cylindrical housing 38 is sealed by a threaded cap 39 and a dowty washer 47 to ensure an airtight seal.
  • the prepared apparatus as shown in figures 5 and 6 is slid onto the end of a CIPP-lined pipe until the end of the pipe registers with the top edge 51 of inner cylinder 34. Due to the weight of the apparatus there will be at the bottom a larger gap between the interior of the outer cylindrical body and the exterior of the CIPP- lined pipe than there will be at the top. Thus caps 39 are removed from housing 38 to provide access to bolts 37 which are suitably adjusted to centralise the position of the pipe within the apparatus.
  • Bolts 45 are then tightened to provide a compression seal of ring 46 around the outer edge of the pipe.
  • the internal joint of the pipe with internal cylinder 34 is sealed using, for example, a standard AMEX-IO seal as is well known by those skilled in the art.
  • a hydraulic ram attached to a vibrating member is used to secure the seal in place by expanding retaining rings and fixing with retaining wedges.
  • a soap solution is applied around the edges of the internal and external seals.
  • Cap 48 is removed from housing 41 exposing aperture 40.
  • a positive pressure of nitrogen is then introduced into the apparatus and the presence or absence of bubbling around the edges indicates the presence or absence of a leak.
  • a replacement polyethylene pipe or the like may be bolted onto outer flange 32.
  • flange 32 is suitably a PN-16 flange, which is able to be easily connected to a similar such standard fitting on a replacement pipe.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Flanged Joints, Insulating Joints, And Other Joints (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)

Abstract

L'invention concerne un appareil pour fournir un joint d'étanchéité externe autour d'un tuyau doublé par chemisage, l'appareil comportant un corps tubulaire (30), dont la dimension interne est légèrement supérieure à la dimension externe du tuyau doublé par chemisage, le corps tubulaire (30) étant adapté à une extrémité pour être connecté à une section de tuyau de remplacement et à l'autre extrémité (31) pour recevoir un tuyau doublé par chemisage de façon à former un joint étanche à l'air autour de la surface externe dudit tuyau doublé par chemisage.
PCT/GB2007/003610 2006-09-23 2007-09-21 Appareil et procédé pour raccorder un tube doublé WO2008035104A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB0904111A GB2454157A (en) 2006-09-23 2009-03-10 Apparatus and method for joining a lined tube

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB0618796.7 2006-09-23
GB0618796A GB2442010A (en) 2006-09-23 2006-09-23 An adaptor for externally connecting a CIPP-lined pipe to a replacement pipe

Publications (1)

Publication Number Publication Date
WO2008035104A1 true WO2008035104A1 (fr) 2008-03-27

Family

ID=37421527

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2007/003610 WO2008035104A1 (fr) 2006-09-23 2007-09-21 Appareil et procédé pour raccorder un tube doublé

Country Status (2)

Country Link
GB (2) GB2442010A (fr)
WO (1) WO2008035104A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3028180A (en) * 1958-09-24 1962-04-03 Joseph B Smith Pipe coupling
DE2237982A1 (de) * 1972-08-02 1974-02-14 Metallgesellschaft Ag Verfahren zur herstellung von korrosionsbestaendigen verbindungen
FR2297372A1 (fr) * 1975-01-13 1976-08-06 Assandri Roberto Dispositif de raccordement pour tuyaux
DE7641030U1 (de) * 1976-12-30 1977-04-21 Rosai, Alfred, 8261 Neumarkt-St Veit Gummidichtungsring mit doppelkeil
EP0015559A1 (fr) * 1979-03-06 1980-09-17 Tokyo Gas Co., Ltd. Dispositif de calfeutrage pour liaison de tube
JPH10141561A (ja) * 1996-11-13 1998-05-29 Hitachi Metals Ltd 防食メカニカル管継手及び防食メカニカル管接続構造

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH024311Y2 (fr) * 1984-09-28 1990-01-31
US4648631A (en) * 1985-12-19 1987-03-10 Rockwell International Corporation Reducing coupling
GB2316144B (en) * 1996-08-09 2000-02-02 Glynwed Pipe Systems Ltd Pipe couplings
US6019396A (en) * 1997-08-27 2000-02-01 Waterworks Technology Development Organization Co., Ltd. Pipe connecting apparatus
GB2404707B (en) * 2003-08-06 2008-03-05 Crane Ltd A flange adapter

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3028180A (en) * 1958-09-24 1962-04-03 Joseph B Smith Pipe coupling
DE2237982A1 (de) * 1972-08-02 1974-02-14 Metallgesellschaft Ag Verfahren zur herstellung von korrosionsbestaendigen verbindungen
FR2297372A1 (fr) * 1975-01-13 1976-08-06 Assandri Roberto Dispositif de raccordement pour tuyaux
DE7641030U1 (de) * 1976-12-30 1977-04-21 Rosai, Alfred, 8261 Neumarkt-St Veit Gummidichtungsring mit doppelkeil
EP0015559A1 (fr) * 1979-03-06 1980-09-17 Tokyo Gas Co., Ltd. Dispositif de calfeutrage pour liaison de tube
JPH10141561A (ja) * 1996-11-13 1998-05-29 Hitachi Metals Ltd 防食メカニカル管継手及び防食メカニカル管接続構造

Also Published As

Publication number Publication date
GB0904111D0 (en) 2009-04-22
GB0618796D0 (en) 2006-11-01
GB2454157A (en) 2009-04-29
GB2442010A (en) 2008-03-26

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