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
  • F16L21/035—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 placed around the spigot end before connection
• • 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
  • F16L27/00—Adjustable joints; Joints allowing movement
  • F16L27/10—Adjustable joints; Joints allowing movement comprising a flexible connection only
  • F16L27/1021—Adjustable joints; Joints allowing movement comprising a flexible connection only comprising an intermediate resilient element, e.g. a ring

Definitions

• Joint arrangement for pipe members comprising a spigot end and a socket end
• the present invention relates to a joint arrangement comprising two members to be joined, for example pipe members comprising a spigot end and a socket end as well as a resilient gasket serving to seal the joint arrangement by the squeezing thereof between the sealing surfaces of the members.
• the gasket In connection with joint arrangements which for example comprise concrete pipes of the socket type, the gasket has to meet two requirements which in themselves are contradictory.
• the gasket must provide a sealing against an inner or outer over pressure. Due to the irregularities of the surfaces of the pipes it is desired that the gasket is both soft and elastic. At the same time it is desired that the gasket has a relatively large width, so as to be adaptable to the tolerance deviations which may occure.
• the gasket should offer such a large resistance against a further compression beyond what is necessary for absorbing the tolerance deviations, that it ensures such a concetric position for the pipes in the socket joint, that no direct contact between the concrete of the socket and the pipe will occur. This. is valid especially in the cases where the individual pipe members form an angle relative to each other. Such a contact between socket and pipe will entail a crushing of concrete and breakage of pipe or socket.
• the object of the present invention is to give instructions for a joint arrangement which gives a solution to the two above mentioned contradictory.
• the solution is according to the invention characterized in that the sealing surfaces of the joint arrangement define a first broader gap holding a first gasket portion which within certain deviations from concentricity forms a main seal between the sealing surfaces, and a narrower guiding gap holding a second gasket portion which absorbs transverse forces before the said deviations are exceeded, for thereby maintaining the main seal.
• a prefered embodiment of the joint arrangement according to the invention is to the effect that the broader gap holding the main seal portion is at least 2.5 times larger than the narrower guiding gap, that the main seal portion is given such dimensions that it in a concentric assembly of the members to be joined is compressed approximately 20 to 30 %, and that the guiding gap portion of the gasket fills the .guiding gap within a tolerance range which on the one hand fills the guiding gap with up to 10% compresion, and on the other hand allows for a play of about 30% of the width of the guiding gap.
• the main seal portion will always fill the maximum gap which can be formed between the sealing surfaces of the members to be joined, and there can at the same time be used a gasket which is so soft that the expansion force which occure due to compression, will not be so large that the socket is broken, or that a too large force is required for putting the pipe members together. If the joint arrangement is influenced by a transverse force which gives rise to a displacement of the members constituting the joint arrangement, both the main seal portion and the guiding gap portion will be compressed at the one side of the joint, whereas on the oposite side they will be relieved.
• a gasket of the type involving a sliding jacket the guiding gap portion of the gasket then having the shape of a sliding gasket which is entrained by the sealing surface of the one member to be joined when the two members are assembled into each other, so that the guiding gap portion in the finished mounted position is constituted by a double sliding jacket.
• Fig. 1 is a diagrammatic view of a joint arrangement according to the invention.
• Fig. 2 is on a larger scale a section through a fraction of the joint arrangement when the joint members are assembled.
• the joint arrangement illustrated in fig. 1 comprises two pipe members 1 and 2 to be joined, the pipe member 1 comprising a spigot end 4 and the pipe member 2 comprising a socket end 8.
• a gasket 3 for example a gasket having a sliding jacket of the type which is further described in Norwegian patent application No. 78 3644, and which has a larger thickness than the distance between the sealing surfaces of the members in mounted position of the joint arrangement.
• the jacket 6 will have a folded position between the sealing surface 9 of the socket end 8 and a carrying surface 10 on the spigot end 4 of the pipe member 1, the surfaces 9 and 10 defining a relatively narrow guiding gap 11 between the spigot and socket end.
• the gasket body 7 must have such a large thickness that it together with the jacket 6 can always fill the largest gap 12 which is formed between the step 5 on the spigot end 4 and the sealing surface 9 of the socket end 8. At the same time the gasket body 7 must be so soft that the expansion force which develops due to the compression during the assembly, will not be so large that the socket end 8 is cracked or that too large a force is required to push the pipe members into each other.
• the sealing surface 9 of the socket end will compress the gasket 3 until a balance is achieved between the transverse force and the carrying ability of the gasket. If the transverse forces are large it is usual that the gasket must be compressed to approximately 50% of its original thickness to achieve such a relation. For a normal rolling gasket joint for a pipe according to for example NS 3028, this will for example mean that a gasket which originally has a thickness of 15 mm will be compressed to 7.5 mm.
• the joint arrangement When using a joint arrangement according to the invention, for example of the embodiment discussed above, the joint arrangement will, when influenced by transverse forces, function in the following way:
• the larger gap 12 between the step 5 on the spigot end 4 and the sealing surface 9 of the socket end has a dimension a of for example 11.25 mm and the guiding gap 11 between the sealing surface 9 of the socket end 8 and the supporting surface 10 of the spigot end 4 has a dimension b of 3 mm, the thickness of the gasket 3 prior to compression being 15 mm and the thickness of jacket 6 being 1.5 mm, the following condition will develop when the joint arrangement is subjected to transverse forces.
• the gasket is compressed approximately 25% corresponding to 3.75 mm by squeezing between the step 5 and the sealing surface 9, the jacket 6 being entrained by the sealing surface 9 inwardly along the supporting surface 10 to end up in a folded condition between the said surfaces for thus filling the guiding gap 11 to a larger or lesser degree.
• the two layers which together constitute 3 mm must be compressed approximately 50% corresponding to 1.5 mm of the double jacket in the area where the transverse forces come into action.
• the sliding jacket 6 and the main seal portion 7 can have surfaces including sawtoothed ribs 13 which slide along each other during assembly, but which in mounted position are locked in each other for thereby affixing the joint arrangement in axial direction.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Joints With Sleeves (AREA)
• Medicines Containing Material From Animals Or Micro-Organisms (AREA)
• Gasket Seals (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=19885332

Family Applications (1)

Country Status (4)

Families Citing this family (1)

Family Cites Families (7)

• 1980
  • 1980-02-18 NO NO800436A patent/NO800436L/no unknown
• 1981
  • 1981-02-13 WO PCT/NO1981/000003 patent/WO1981002336A1/en not_active Ceased
  • 1981-02-13 EP EP81900461A patent/EP0045768A1/en not_active Withdrawn
  • 1981-10-16 DK DK459481A patent/DK459481A/da not_active Application Discontinuation

Non-Patent Citations (1)

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