WO1993019319A1 - Raccord destine a des tuyaux - Google Patents

Raccord destine a des tuyaux Download PDF

Info

Publication number
WO1993019319A1
WO1993019319A1 PCT/GB1993/000537 GB9300537W WO9319319A1 WO 1993019319 A1 WO1993019319 A1 WO 1993019319A1 GB 9300537 W GB9300537 W GB 9300537W WO 9319319 A1 WO9319319 A1 WO 9319319A1
Authority
WO
WIPO (PCT)
Prior art keywords
pipe
spigot
rib
sleeve
ribs
Prior art date
Application number
PCT/GB1993/000537
Other languages
English (en)
Inventor
Andrew Welfare
Original Assignee
Wask-Rmf 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 Wask-Rmf Limited filed Critical Wask-Rmf Limited
Priority to GB9418830A priority Critical patent/GB2279715B/en
Publication of WO1993019319A1 publication Critical patent/WO1993019319A1/fr

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
    • F16L33/00—Arrangements for connecting hoses to rigid members; Rigid hose connectors, i.e. single members engaging both hoses
    • F16L33/22—Arrangements for connecting hoses to rigid members; Rigid hose connectors, i.e. single members engaging both hoses with means not mentioned in the preceding groups for gripping the hose between inner and outer parts
    • F16L33/225—Arrangements for connecting hoses to rigid members; Rigid hose connectors, i.e. single members engaging both hoses with means not mentioned in the preceding groups for gripping the hose between inner and outer parts a sleeve being movable axially

Definitions

  • the present invention relates to a pipe coupling.
  • Plastics pipes are widely used in, for example, fuel gas and water distribution networks where it is important that all connections between pipes and between pipes and various applications are very reliable.
  • the connections must be leak proof and strong enough to prevent them from being pulled apart as a result of any end load on the pipe. Such an end load may result from thermal expansion or contraction in the pipes length.
  • Plastics pipes are generally interconnected end to end by one of a variety of welding processes, it being unnecessary to provide an intermediate coupling of for example metal.
  • plastics pipes have to be coupled to appliances and in such circumstances the interconnection between the plastics pipe and an appliance spigot pushed into an end of the plastics pipe must be able to resist high end loads.
  • couplings are only acceptable if when on test and the being subjected to an end load the plastics pipe fails before the plastics pipe is torn from the coupling.
  • the spigot may of course; be integral with an appliance :. ⁇ which the pipe i_ ic be connect ed, or integral with a coupling body supporting one or more service spigots to enable the interconnection of pipes in any appropriate manner.
  • GB 1596112 do provide acceptable results in most circumstances but it has been found on occasions when subjecting such couplings to the standard end load tests that the high density polyethylene pipe fails in the vicinity of the first rib on the spigot, that is the rib closest to the free end of the spigot which is inserted into the pipe end during the coupling assembly procedure. It is thus apparent that the characteristics of the known coupling when used with medium density polyethylene pipes are not precisely reproduced when used with high density polyethylene pipes.
  • a pipe coupling comprising a tubular spigot a free end of which in use is inserted into an open end of a tubular pipe, and a sleeve which in use is pushed onto the pipe end into which the spigot has been inserted so that the pipe end is gripped between the spigot and the sleeve, the outer surface of the spigot defining a plurality of circumferential ribs separated by circumferential grooves, wherein the rib outside diameter increases from the rib nearest to the spigot free end to the rib farthest from the spigot free end, and each groove is dimensioned such that, given a pipe end having a wall thickness equal to the maximum wall thickness with which the coupling is intended to be used, the groove volume is at least as great as the volume of material displaced as a result of the adjacent rib which is closest to the spigot free end being forced into the pipe wall.
  • the compressive forces applied to the pipe wall by the first rib that is the rib nearest to the free end of the spigot which is first pushed into the pipe, is less than the compressive forces resulting from the ribs of greater outside diameter.
  • the end load is distributed between the different grooves..
  • the groove volume is sufficiently large to receive material displaced by the ribs, there is no tendency for material to be forced a considerable distance longitudinally relative to the spigot and - this again reduces the stresses to which the pipe is subjected adjacent the radial outer edges of the ribs.
  • each adjacent pair of ribs Preferably in each adjacent pair of ribs the rib nearest to the spigot free end has a smaller outside diameter than the other rib of the pair.
  • the difference in outside diameter between one pair of adjacent ribs may be the same as the difference in outside diameter between any adjacent pair of ribs.
  • Each groove may be defined between two side walls of the immediately adjacent pair of ribs and a base which is parallel to an axis about which the spigot is rotationally symmetrical.
  • Each rib may define a sharp radially outer edge or the rib may be shaped to avoid defining a sharp edge by for example providing a flat radially outer surface.
  • Each rib may be generally conical in cross-section, the cone coming to a point if a sharp rib edge is defined or being. truncated to form a frusto-conical cross-section if the radially outer surface of the rib is flat. All the ribs may have substantially the same cone angle in cross section.
  • the sleeve may define a cylindrical inner wall surface or a frusto-conical inner wall surface.
  • the sleeve may define a partially cylindrical inner wall surface, the cylindrical inner surface being joined to a frusto-conical inner wall surface.
  • Figure 1 is a cross-sectional view of a first embodiment of the invention Illustrating the relative dimensions of the coupling components and of various possible pipe ends;
  • Figure 2 Illustrates the relative dimensions of adjacent ribs and grooves in the embodiment of Figure 1;
  • Figure 3 Illustrates a second embodiment of - the invention in which ribs are provided with flat radialiv outer surfaces:
  • Figure 4 illustrates a third embodiment of the present invention in which a tapered sleeve is provided;
  • Figure 5 illustrates a fourth embodiment of the invention in which the sleeves have a part cylindrical and part frusto-conical inner surface.
  • the illustrated coupling comprises a spigot 1 extending from a flange 2, the flange 2 being intended for connection to any appropriate appliance.
  • a sleeve 3 having chamfered ends may be slipped over the spigot so as to assume the position shown in the fully assembled coupling.
  • the sleeve 3 is first pushed onto and away from the pipe end, this being relatively easy to achieve as the cylindrical inner surface of the sleeve 3 has a diameter equal to ' the maximum outer diameter of any pipe with which the coupling is intended to be used.
  • the spigot is pushed into the pipe end, causing the pipe end to expand to a relatively small extent.
  • the sleeve is forced back onto the . pipe end so as to compress the pipe end and force each of a series of six ribs 4 defined on the outer surface of the spigot into the inner wall of the pipe.
  • the pipe end is thus gripped between the spigot 1 and the sleeve 3.
  • the outside diameters of the ribs 4 increase progressively from the free end of the spigot 1, that is the end of the spigot remote from the flange 2. It can be seen that the difference in outside diameter between any pair of adjacent ribs is substantially the same for all of the adjacent pairs of ribs. It should also be noted that the width of the grooves defined between adjacent pairs of ribs increases away from the spigot free end. This is to ensure that material displace by any one rib can be accommodated in the groove which is on the side of that rib remote from the spigot free end.
  • Figure 1 indicates by line 5 the maximum outside diameter of any pipe which complies with the dimensional tolerances intended to be accommodated by the illustrated coupling.
  • the line 6 indicates the minimum acceptable outside diameter of the pipe, the line 7 the maximum acceptable inner diameter of the pipe and the line 8 the minimum acceptable inner diameter of • the pipe.
  • the pipe wall dimensions are also maintained between maximum and minimum wall thicknesses, the distance between line 5 and line 7 corresponding to the minimum wall thickness and the distance between lines 6 and S corresponding to the maximum wall thickness.
  • each groove is capable of just accommodating all the material displaced by the immediately adjacent rib on the free spigot end side thereof.
  • Figure 2 the line 9 represents the surface of a cylinder located radially inwards from the inner surface of the sleeve 3 of Figure 1 by a distance equal to the maximum pipe wall thickness.
  • the areas labelled 10 are of the same cross-sectional area, and the areas labelled 11 are of the same cross-sectional area. This relationship is maintained along the full length of the spigot.
  • any material displaced by a groove is always displaced by the advancing sleeve on to the far side of that groove when viewed in the direction of advance of the sleeve, none of the material displaced by one rib is forced to flow over the crest of the next rib.
  • the base 12 of the groove nearest to the spigot free end is narrower than the base 13 of the next groove which in turn is narrower than the base 14 of the next groove.
  • This increase in base width is necessary to maintain the capacity of each groove to receive material displaced by the adjacent rib on the side nearest to the spigot free end, given the dimensional relationships of the grooves and ribs, that is each rib defining a cone in cross-section with the cone angle being the same for each rib, and each groove having a flat base with all the groove bases lying on a common cylindrical surface centred or. the spigot axis.
  • ribs and grooves can have different configurations, providing the rib outside diameters increase in the direction away from the spigot free end, and providing each groove is capable of receiving material displaced by the immediately adjacent rib on the side thereof closer to the spigot free end.
  • each rib 4 does not terminate in a radially outer point it is relatively sharp. It is thought that couplings used with certain grades of high density polyethylene will not be adversely affected by such relatively sharp ribbed edge but certain grades may be more prone to a stress cracking phenomena and therefore it may be preferred, in some of these applications, to provide a kerb or flat surface of significant dimensions at the radially outer end of each rib to avoid such potential hazards.
  • Figure 3 It should be realised however that given that the effective cross-sectional area of each rib for a particular rib height has been increased, it is also necessary to increase the width of the grooves provided between each adjacent pair of ribs. This is illustrated in Figure 3. It will be noted that in all of the drawings the same lines have been incorporated to illustrate the relative dimensions of the ribs and of the pipe ends. Reference numerals have not been included in Figures 3 to 5.
  • FIG 4 this illustrates a coupling incorporating a spigot identical to that of Figure 1 but a sleeve which has an internal frusto-conical surface rather than a cylindrical surface.
  • the sleeve shown in Figure 4 defines an inner surface which is of slightly greater diameter adjacent the flange as compared with the spigot free end.
  • Such an arrangement could be used to reduce maximum compressions and ease of assembly. It might also be possible with such an arrangement to reduce the overall coupling length.
  • Figure 5 this again shows a spigot and flange arrangement identical to that of Figure 1 but in use with a sleeve having a section adjacent the flange which has a frusto-conical inner surface and a section remote from the flange which has a cylindrical inner surface.
  • Figure 5 exhibit features common to both Figures 1 and 4.
  • sleeve internal diameter may be selected: Sleeve Minimum Diameter 125.8 mm
  • the outside diameter of the base of each of the grooves is 97.3 mm. It is then necessary to calculate the height of the first rib such ' that given a pipe which is just within the maximum tolerances set out above the penetration of the first rib does not exceed a predetermined limit. Tests have shown that an appropriate penetration depth maximum of 13% of the wall thickness is appropriate. .
  • the outside diameter of the pipe when constrained by the sleeve Is at least 125.8 mm.
  • the pipe would have an Internal diameter of 100.4 mm if none of the pipe material was displaced.
  • a 13% penetration of a wall 12.7 mm thick represents a penetration of 1.65 m ⁇ ; and thus the maximur. outside diameter of the first groove should be 100.4 mm + 3.3 mm to give a total of 103.7 mm.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Rigid Pipes And Flexible Pipes (AREA)
  • Joints With Sleeves (AREA)
  • Mutual Connection Of Rods And Tubes (AREA)

Abstract

Un raccord, destiné à des tuyaux, comprend un manchon tubulaire (1) et une gaine (3). On l'utilise en insérant une extrémité libre du manchon (1) dans une extrémité ouverte du tuyau et on enfile la gaine (3) sur l'extrémité du tuyau de façon à coincer ce dernier entre le manchon (1) et la gaine (3). La surface externe de ce manchon (1) présente plusieurs crêtes (4) et sillons annulaires. Le diamètre extérieur des crêtes (4) augmente à partir de l'extrémité libre du manchon (1). Chaque sillon est dimensionné de manière que son volume soit au moins égal à celui du matériau qui est repoussé du fait que la crête adjacente (4) pénètre en force deans la paroi du tuyau à mesure que l'on assemble ce raccord. La configuration est telle que la charge finale du raccord se répartit entre les différents sillons, quelle que soit l'épaisseur de la paroi du tuyau.
PCT/GB1993/000537 1992-03-18 1993-03-15 Raccord destine a des tuyaux WO1993019319A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB9418830A GB2279715B (en) 1992-03-18 1993-03-15 Pipe coupling

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB929205824A GB9205824D0 (en) 1992-03-18 1992-03-18 Pipe coupling
GB9205824.7 1992-03-18

Publications (1)

Publication Number Publication Date
WO1993019319A1 true WO1993019319A1 (fr) 1993-09-30

Family

ID=10712325

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1993/000537 WO1993019319A1 (fr) 1992-03-18 1993-03-15 Raccord destine a des tuyaux

Country Status (3)

Country Link
AU (1) AU3758893A (fr)
GB (2) GB9205824D0 (fr)
WO (1) WO1993019319A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3330588A1 (fr) * 2016-12-01 2018-06-06 Vinko Rebersek Raccord de tuyau

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1185220A (en) * 1966-07-14 1970-03-25 Frederick Russel Duffield Improvements in hose end fittings
US4257629A (en) * 1978-05-01 1981-03-24 Rain Bird Sprinkler Mfg. Corp. Flexible conduit repair coupling
EP0066742A1 (fr) * 1981-06-06 1982-12-15 Rasmussen GmbH Raccord pour tuyaux flexibles
US4817997A (en) * 1987-06-25 1989-04-04 Ingram Thomas L Hose coupling
WO1992016782A1 (fr) * 1991-03-22 1992-10-01 Wask-Rmf Limited Raccord de tuyau

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1185220A (en) * 1966-07-14 1970-03-25 Frederick Russel Duffield Improvements in hose end fittings
US4257629A (en) * 1978-05-01 1981-03-24 Rain Bird Sprinkler Mfg. Corp. Flexible conduit repair coupling
EP0066742A1 (fr) * 1981-06-06 1982-12-15 Rasmussen GmbH Raccord pour tuyaux flexibles
US4817997A (en) * 1987-06-25 1989-04-04 Ingram Thomas L Hose coupling
WO1992016782A1 (fr) * 1991-03-22 1992-10-01 Wask-Rmf Limited Raccord de tuyau

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3330588A1 (fr) * 2016-12-01 2018-06-06 Vinko Rebersek Raccord de tuyau

Also Published As

Publication number Publication date
GB2279715A (en) 1995-01-11
GB9418830D0 (en) 1994-11-09
GB9205824D0 (en) 1992-04-29
GB2279715B (en) 1995-08-02
AU3758893A (en) 1993-10-21

Similar Documents

Publication Publication Date Title
JPH0351500B2 (fr)
US5188401A (en) Pipe coupling with interlocked and segmented grip ring
US5007667A (en) Crimped sleeve to tube joint
US2139413A (en) Joint for pipes
US5524939A (en) Apparatus for and method of attaching hoses and tubes to a fitting
AU701403B2 (en) Interlocked restraint for a plastic pipe joining system
US5056833A (en) Flexible pipe coupling
US3637239A (en) Thrust-resistant pipe joint
DK172246B1 (da) Fremgangsmåde til fremstilling af en højtryksslangeforbindelse, samt en højtryksslangeforbindelse
EP2029927B1 (fr) Dispositif d'étanchéité à nervures pour tubage ondulé en acier inoxydable
CA1300527C (fr) Tuyau ondule, en plastique, a grand diametre
US5437310A (en) Plug assembly
US4142581A (en) Tube-hole structure for expanded tube-to-tube-sheet joint
EP0480478A1 (fr) Raccord de tuyaux
US5168618A (en) Method of forming a crimped sleeve to tube joint
GB2059533A (en) Method of joining pipes to pipe sleeves
WO1996010712A1 (fr) Raccord universel a attache en u pour tubes
GB2206660A (en) Pipe joint
US3563574A (en) Coupling for plastic pipe
US6108895A (en) Method of axially swaging a male end fitting assembly
GB2032557A (en) Fittings for fluid-tight connection to tubular members
US5116087A (en) Pipe which is configured for coupling to another pipe
WO1993019319A1 (fr) Raccord destine a des tuyaux
WO1993020381A1 (fr) Tuyau de refection interne pour canalisations
US3671060A (en) Insulating fitting and method for manufacturing

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AT AU BB BG BR CA CH CZ DE DK ES FI GB HU JP KP KR LK LU MG MN MW NL NO NZ PL PT RO RU SD SE SK UA US VN

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA