Search

EP-4511587-B1 - A PIPE COUPLING FOR CONNECTING CIRCULAR ELEMENTS

EP4511587B1EP 4511587 B1EP4511587 B1EP 4511587B1EP-4511587-B1

Inventors

  • SIMONSEN, Christian Henrik

Dates

Publication Date
20260513
Application Date
20230414

Claims (8)

  1. A pipe coupling (1) for connecting circular elements (2), said pipe coupling (1) comprising • a clamping ring (3) including an inner annular concave groove (4), • at least one fastening means (5) arranged to contract said clamping ring (3), and • a plurality of grip elements (6) each having a plurality of gripping protrusions (7) on an inwards facing surface (8) and a convex protrusion (9) on an opposite outwards facing surface (10), wherein said convex protrusion (9) of said plurality of grip elements (6) is arranged in said inner annular concave groove (4) of said clamping ring (3) so that said plurality of grip elements (6) may tilt in relation to said clamping ring (3), wherein said inner annular concave groove (4) and said plurality of grip elements (6) are arranged at a first axial coupling end (18) of said clamping ring (3) for connecting said pipe coupling (1) to a first circular element (19) of said circular elements (2), characterized in that an inner annular gasket groove (20) comprising a gasket (21) is arranged at a second axial coupling end (22) of said clamping ring (3) for connecting said pipe coupling (1) to a second circular element (23) of said circular elements (2), wherein said plurality of grip elements (6) has a longitudinal extent in the axial direction of said pipe coupling (1) and wherein said convex protrusion (9) is displaced from a middle of said grip elements (6) in a direction towards said first axial coupling end (18).
  2. A pipe coupling (1) according to claim 1, wherein said pipe coupling (1) further comprises retainer means (11) arranged to retain said convex protrusion (9) of said plurality of grip elements (6) in said inner annular concave groove (4) of said clamping ring (3).
  3. A pipe coupling (1) according to claim 1 and 2, wherein said pipe coupling (1) further comprises holding means (12) arranged to maintain said plurality of grip elements (6) in an initial position at least until said least one fastening means (5) contract said clamping ring (3).
  4. A pipe coupling (1) according to any of the preceding claims, wherein said clamping ring (3) comprises two or more clamping ring parts (13).
  5. A pipe coupling (1) according to any of the preceding claims, wherein said plurality of grip elements (6) comprises, a plurality of first grip elements (14) having first gripping protrusions (15) with a first contact area facing inwards, and a plurality of second grip elements (16) having second gripping protrusions (17) with a second contact area facing inwards, wherein said first contact area is greater than said second contact area.
  6. A pipe coupling (1) according to claim 6, wherein said inwards facing surface (8), from which said second gripping protrusions (17) of said plurality of the second grip elements (16) protrudes, is concave.
  7. A pipe coupling (1) according to claim 5 or 6, wherein said first gripping protrusions (15) are made from a plastic material and wherein said second gripping protrusions (17) are made from metal.
  8. A pipe coupling (1) according to any of the preceding claims, wherein said concave groove (4) is wider than said convex protrusion (9) measured in the axial direction of said pipe coupling (1) between an apex (24) of said convex protrusion (9) and a tilt axis (25) of said grip elements (6).

Description

Background of the invention The invention relates to a pipe coupling for connecting circular elements. The pipe coupling comprises a clamping ring and at least one fastening means arranged to contract the clamping ring. Description of the Related Art Pipe couplings are used for connecting many kinds of circular element such as pipes, valve flanges, pumps, other pipe couplings or other to each other typically in some sort of a piping system such as at a waterworks, a water distribution system, an industrial plant or other. However, when e.g., a circular element in the form of a pipe is connected to another circular element in the form of a flange of a valve it can be difficult to securely fixate the regular pipe end to the valve flange without the inside fluid pressure pushing the pipe and the valve axially apart e.g., when the valve is closed, and the fluid pressure rises. Same problem occurs e.g., when two regular pipe end has to be connected. Thus, from the European patent EP 2 905 522 B1 and the US patent US 7,837,239 B2 is known to form a pipe coupling by means of a clamping ring having an inner inclined surface against which wedge-shaped grip elements slide to provide a strong hold against a regular smooth and plane pipe surface. However, when this coupling design is used on weaker circular elements in the form of weaker pipe types such as plastic pipes, thinner metal pipes or composite pipes and the pipe is subjected to a pull away from the coupling, the wedging effect can be so forceful that the pipe is deformed to a degree where the wedge-shaped grip elements are pulled out of the pipe coupling and the pipe coupling is pulled apart. From the US patent application US 1 930 194 A it is known to form a pipe coupling having a housing with two annular recesses in which movable or rocking pawls are arranged so that when a pipe is inserted into the coupling the pawls will rock and thereby engage the pipe. However, such a coupling design's ability to fixate the pipe is not high and the coupling can only be used at very low pressures. An object of the invention is therefore to provide for a better pipe coupling design. The invention The invention provides for a pipe coupling for connecting circular elements. The pipe coupling comprises a clamping ring including an inner annular concave groove and at least one fastening means arranged to contract the clamping ring. The pipe coupling further comprises a plurality of grip elements each having a plurality of gripping protrusions on an inwards facing surface and a convex protrusion on an opposite outwards facing surface. The convex protrusion of the plurality of grip elements is arranged in the inner annular concave groove of the clamping ring so that the plurality of grip elements may tilt in relation to the clamping ring. The inner annular concave groove and the plurality of grip elements are arranged at a first axial coupling end of the clamping ring for connecting the pipe coupling to a first circular element of the circular elements, and wherein an inner annular gasket groove comprising a gasket is arranged at a second axial coupling end of the clamping ring for connecting the pipe coupling to a second circular element of the circular elements. The plurality of grip elements has a longitudinal extent in the axial direction of the pipe coupling and the convex protrusion is displaced from a middle of the grip elements in a direction towards the first axial coupling end. Forming the grip elements with convex protrusions on the backside and arranging these in an inner annular concave groove of the clamping ring enables that the grip elements may tilt - either by rotating in the concave groove or by rolling slightly on the concave groove surface - in the concave groove and exert more pressure on the outer surface of the circular element if the circular element is moved axially. Thus, the grip elements remain axially fixed or only move slightly in the axial direction when the circular element is pulled axially away from the pipe coupling and they thereby stay seated firmly in the concave groove hereby preventing that the grip elements are pulled out of the clamping ring even at a forceful axial pull in the circular element. Forming the pipe coupling with the grip elements at first axial coupling end of the clamping ring and a gasket arranged in an inner annular gasket groove at the second axial coupling end of the clamping ring is advantageous in that the pipe coupling hereby can be used for connecting a first circular pipe element in the form of a regular pipe to a second circular pipe element in the form of a different type of circular element than a pipe - such as a circular flange of a valve, a pump, a pipe of other thereby making the pipe coupling more versatile and making the pipe coupling fast to use in that both the first circular pipe element and the second circular pipe element can be connected contracting the clamping ring by means of the fastening mean