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"Assembly Having a Flange" in Patent Application Approval Process

2014-02-26 14:45:20   COMMENT:0 HITS:
By a News Reporter-Staff News Editor at Politics & Government Week -- A patent application by the inventor Freund, Wolfgang (Gelsenkirchen, DE), filed on April 13, 2012, was made available online on February 6, 2014, according to news reporting originating from Washington, D.C., by VerticalNews correspondents.
 
This patent application has not been assigned to a company or institution.
 
The following quote was obtained by the news editors from the background information supplied by the inventors: "Furthermore, the invention also relates to a similar assembly with an adapter ring for a pressure-bearing flange connection of two pipe ends for arranging between two flanges.
 
"Flanges of the type referred to in the introduction are regularly used on pressure-bearing pipe connections. In this case, it preferably concerns weld-on flanges, weld neck flanges or loose flanges with a weld-on collar, especially in accordance with EN 1092-1, DIN 2632 to DIN 2638, ASME B16.5 or ASME B16.47.
 
"Flange connections are known from U.S. Pat. No. 5,904,382 A, in which flange connections the screws are not stressed in the axial direction of the pipe since the forces in the axial direction of the pipe are absorbed by means of encompassing clamps which exert pressure upon the seal over defined inclined planes. The gap between the flanges which is provided according to plan serves only for locating the seal in the main force flux in a guaranteed manner A compensation of flange-plate inclinations is neither planned nor possible with this construction. The flange plate rotations need to be almost 0 so that pressure can be transmitted onto the seal by the clamps via the inclined planes.
 
"A flange connection is known from DE 43 40051 A1, in which a flange-plate inclination, on account of the screwing forces, attributable to the shape of the flange sealing surface, which occur during assembly, leads to no lowering of the force on the seal. Inclinations of the flange plates as a result of weld contraction stresses extend in exactly the opposite direction and cannot be compensated by this construction.
 
"(D1) GB 577,700 A
 
"An application was filed in this case for a flange connection in which the flange plates lay one upon the other up to the outside diameter of the flange plates, that is to say a rotation of the flange is not permissible according to plan. The gap provided on the inside diameter of the flanges serves only for the internal pressure being able to act on the inside diameter of the seal and therefore forces the seal radially outward, which means additional seal tightness. A compensation of flange-plate inclinations is neither planned nor possible with this construction.
 
"(D2) U.S. Pat. No. 5,904,382 A
 
"An application was filed in this case for flange connections in which the screws are not stressed in the axial direction of the pipe since the forces in the axial direction of the pipe are absorbed by encompassing clamps which exert pressure onto the seal via defined inclined planes. The gap between the flanges which is provided according to plan serves only for locating the seal in the principle force flux in a guaranteed manner. A compensation of flange-plate inclinations is neither planned nor possible with this construction. The flange-plate rotations need to tend towards zero so that pressure can be transmitted onto the seal by the clamps via the inclined planes.
 
"DE 43 40051 A1 features a flange connection in which a flange-plate inclination, on account of the screwing forces, attributable to the shape of the flange sealing surface, which occur during assembly, leads to no lowering of the force on the seal. Inclinations of the flange plates as a result of weld contraction stresses regularly extend in the opposite direction and cannot be compensated by this construction.
 
"Described in DE 295 04 402 U1 is the known geometry of the Jungtec serrated seal with soft material insert. The lateral serrations in this case fix the soft material insert which is to provide the primary sealing. A compensation of flange-blade inclinations is possible only to a limited extent with this construction. In the case of larger flange-blade inclinations, the soft material seal is unloaded and the metallic serrated comb is loaded.
 
"On account of the welding of flange which is to be used to the connecting pipe, inclinations, convexities and corrugations on the flange sealing surface regularly occur as a result of weld contraction stresses. On account of the high requirements for evenness of flange seals with O-rings in annular grooves, cost-intensive remachining operations of the flange sealing surface are necessary."
 
In addition to the background information obtained for this patent application, VerticalNews journalists also obtained the inventor's summary information for this patent application: "The invention is based on the object of preventing this additional cost of remachining
 
"Proposed for achieving the object according to the invention are flanges, adapter rings or arrangements of the type referred to in the introduction which have the additional features in the claims.
 
"The invention is especially based on the knowledge that the evenness deviation on flange sealing surfaces almost always has a position inclination on the outside diameter so that the flange sealing surface describes a convex concavity. This inclination leads to the O-ring seal, with its projection from the seal groove beyond the sealing surfaces in some cases, no longer being in the position to compensate the tolerance-related waviness of the flange sealing surface over the circumference. The systematic inclination, especially as a result of the welding distortion, already consumes a large part of the available deformation path of the seal for its compensation. This inclination is a frequent reason for the necessity of a remachining of the flange face, which is particularly costly at site after the welding process. The design according to the invention of the flange is based on a corresponding inclination of the sealing surface of the mating flange and is geometrically prepared in a way that this inclination no longer decimated the squashing capability of the O-ring seal in its arrangement in the seal groove and the complete deformation capability of the O-ring seal is correspondingly made available for compensation of tolerance-related evenness defects of the oppositely-disposed flange sealing surface. The overriding idea of the invention lies in the transfer of the actually unplanned--but according to the invention recognized as being systematic--deviation of sealing surfaces of mating flanges into a planned consideration of this deviation by means of the geometry of the flange according to the invention.
 
"In this case, axially on average with regard to a surface means that this surface has an area-averaged axial position and consequently, according to the invention, this area-weighted axial position of the inner surface in relation to the outer surface has an axial offset, or the radially inner surface is located axially further towards the pipe end in relation to the radial outer surface. In other words, this means that the flange or the adapter ring extends in the circumferential direction around a central axis and surface normals of sealing surfaces on the flange or adapter ring extend on average basically parallel or anti-parallel along the axial direction. The area-averaged axial position of the inner surface is set back in relation to the outer surface by an axial offset in terms of the surface normals of the inner surface or of the outer surface. The design according to the invention of an adapter ring for arranging between two flanges or mating flanges is based on the same idea as the flange according to the invention.

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