Torque absorbing surface

Abstract

To provide a favorable torque absorbing surface.SOLUTION: Multiple raised surfaces on a platform absorb torque of a fastener contacting surfaces while rotating relatively to the platform. Significant disproportionate increase in torque compared with associated increase in bolt stress is observed by increased felt torque when the fastener is tightened. Raised surfaces are used on lugs of a mechanical pipe coupling to increase the fastener's resistance to damage when powered tools are used to apply torque to the fastener.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application is based on and claims the benefit of priority to U.S. Provisional Application No. 63 / 112,194, filed November 11, 2020, which is hereby incorporated by reference in its entirety.

[0002] The present invention relates to surface features that engage rotational fastener elements. [Background technology]

[0003] (background) The increased use of power tools, particularly impact wrenches, in the field allows relatively large torques to be applied to fasteners with little physical effort on the part of the technician. This combination of factors has resulted in an increase in the rate at which bolts are over-torqued, and in some cases has the potential to do so significantly, leading to damage when those bolts are over-torqued by technicians with high powered impact wrenches. It would therefore be advantageous if measures could be taken to increase the resistance of bolts to damage when power tools are used. Summary of the Invention [Means for solving the problem]

[0004] (overview) The present invention relates to a platform for contacting a fastener element in combination, the fastener element being rotatable about an axis oriented transversely to the platform. In an exemplary embodiment, the platform comprises a base surface. A plurality of raised surfaces protrude transversely to the base surface for contacting the fastener element. Each raised surface comprises a plateau. Each raised surface is separated from at least an adjacent one of the raised surfaces by a channel positioned therebetween.

[0005] As an example, the fastener element may comprise a threaded nut or the head of a threaded bolt.

[0006] In a specific exemplary design, each plateau has a height of 0.060 inches above the base surface, and in practical designs, each plateau may have a height in the range of 0.020 inches to 0.1 inches above the base surface. Further, by way of example, each plateau has a minimum surface area of ​​0.010 square inches, and in practical designs, each plateau may have a surface area in the range of 0.010 square inches to 0.1 square inches. In some embodiments, each plateau has a minimum surface area in the range of 0.020 to 0.075 square inches.

[0007] In an exemplary embodiment, at least one of the raised surfaces has a polygonal cross-sectional shape. Further, by way of example, at least one of the raised surfaces may have a rounded cross-sectional shape. In a practical exemplary embodiment, at least one of the raised surfaces is tapered, and at least one of the raised surfaces has a circumference at the plateau that is smaller than the circumference at the base surface.

[0008] In an exemplary embodiment, the fastener element is softer than the plurality of raised surfaces. In a particular example, the fastener element may comprise steel and the plurality of raised surfaces may comprise ductile iron.

[0009] The present invention further encompasses a coupling for joining pipe elements in an end-to-end relationship. In certain exemplary embodiments, the coupling comprises a first section having first and second ends disposed on opposite sides and a second section having first and second ends disposed on opposite sides. A first fastener attaches the first end of the first section to the first end of the second section. A second fastener attaches the second end of the first section to the second end of the second section such that the sections enclose a central space for receiving the pipe element. First and second connecting members are positioned at each of the first and second ends of each of the first and second sections, respectively. In exemplary embodiments, each connecting member comprises a base surface oriented transversely relative to one of the fasteners. A plurality of raised surfaces project transversely relative to the base surface and are engageable with one of the fasteners. Each raised surface includes a flat area. Each raised surface is separated from at least an adjacent one of the raised surfaces by a channel positioned therebetween.As an example, the fastener may include a threaded nut engageable with one of the raised surfaces and / or a threaded bolt having a head engageable with one of the raised surfaces.

[0010] In a specific exemplary design, each plateau has a height of 0.060 inches above the base surface, and in practical designs, each plateau may have a height in the range of 0.020 inches to 0.1 inches above the base surface. Further, by way of example, each plateau has a minimum surface area of ​​0.010 square inches, and in practical designs, each plateau may have a surface area in the range of 0.010 square inches to 0.1 square inches. In some embodiments, each plateau has a minimum surface area in the range of 0.020 to 0.075 square inches.

[0011] In an exemplary embodiment, at least one of the raised surfaces has a polygonal cross-sectional shape. Further, by way of example, at least one of the raised surfaces may have a rounded cross-sectional shape. In a practical exemplary embodiment, at least one of the raised surfaces is tapered, and at least one of the raised surfaces has a circumference at the plateau that is smaller than the circumference at the base surface.

[0012] In an exemplary embodiment, the fastener element is softer than the plurality of raised surfaces. In a particular example, the fastener may comprise steel and the plurality of raised surfaces may comprise ductile iron. In an exemplary embodiment, the plurality of raised surfaces may be cast integrally with the coupling.

[0013] The invention further includes a flange mountable on the pipe element. In an exemplary embodiment, the flange comprises a ring having a contact surface adapted to touch the mating flange, and an exposed surface arranged opposite the contact surface. By way of example, the exposed surface comprises a base surface and a plurality of raised surfaces projecting transversely relative to the base surface. Each raised surface comprises a plateau and each raised surface is separated from at least adjacent ones of the raised surfaces by a channel located therebetween. In a practical example, the plurality of raised surfaces extend around the entire exposed surface.

[0014] In a specific exemplary design, each plateau has a height of 0.060 inches above the base surface, and in practical designs, each plateau may have a height in the range of 0.020 inches to 0.1 inches above the base surface. Further, by way of example, each plateau has a minimum surface area of ​​0.010 square inches, and in practical designs, each plateau may have a surface area in the range of 0.010 square inches to 0.1 square inches. In some embodiments, each plateau has a minimum surface area in the range of 0.020 to 0.075 square inches.

[0015] In an exemplary embodiment, at least one of the raised surfaces has a polygonal cross-sectional shape. Further, by way of example, at least one of the raised surfaces may have a rounded cross-sectional shape. In a practical exemplary embodiment, at least one of the raised surfaces is tapered, and at least one of the raised surfaces has a circumference at the plateau that is smaller than the circumference at the base surface.

[0016] In an exemplary embodiment, the fastener is softer than the plurality of raised surfaces. In a particular example, the fastener may comprise steel and the plurality of raised surfaces may comprise ductile iron. In an exemplary embodiment, the plurality of raised surfaces may be integrally cast with the flange.

[0017] The present invention further encompasses a flange coupling for joining pipe elements. In an exemplary embodiment, the flange coupling comprises a first ring having a first contact surface and a first exposed surface disposed on opposite sides, and a second ring having a second contact surface and a second exposed surface disposed on opposite sides. The second contact surface touches the first contact surface. A plurality of fasteners extend through the first and second rings. Each of the fasteners comprises at least one rotatable member that engages at least one of the exposed surfaces of one of the rings. In an exemplary embodiment, the at least one exposed surface comprises a base surface. A plurality of raised surfaces project transversely relative to the base surface. Each raised surface comprises a plateau. Each raised surface is separated from at least an adjacent one of the raised surfaces by a channel positioned therebetween.

[0018] In an exemplary embodiment, the plurality of raised surfaces extend around the entire exposed surface. Further, by way of example, at least one of the raised surfaces has a polygonal cross-sectional shape or a round cross-sectional shape. In an exemplary embodiment, at least one of the raised surfaces is tapered, and at least one of the raised surfaces has a smaller circumference at the plateau than the circumference at the base surface. By way of example, the rotatable member may comprise a threaded nut engageable with at least one of the raised surfaces, and / or a threaded bolt having a head engageable with one of the raised surfaces.

[0019] In an exemplary embodiment, the rotatable member is softer than the plurality of raised surfaces. In a specific exemplary embodiment, the fastener may comprise steel and the plurality of raised surfaces may comprise ductile iron. In a specific exemplary embodiment, the plurality of raised surfaces are integrally cast with at least one exposed surface. The present specification also provides, for example, the following items: (Item 1) In combination, a platform in contact with a fastener element, the fastener element being rotatable about an axis oriented transversely relative to the platform, the platform comprising: A base surface; a plurality of raised surfaces projecting transversely relative to the base surface for contacting the fastener element, each of the raised surfaces comprising a plateau, each of the raised surfaces being separated from at least adjacent ones of the raised surfaces by a channel positioned therebetween; A combination that includes: (Item 2) 2. The combination of claim 1, wherein the fastener element comprises a threaded nut. (Item 3) 2. The combination of claim 1, wherein the fastener element comprises a head of a threaded bolt. (Item 4) 2. The combination of claim 1, wherein each of the plateaus has a height of 0.060 inches above the base surface. (Item 5) 2. The combination of claim 1, wherein each of the plateaus has a height above the base surface in the range of 0.020 inches to 0.1 inches. (Item 6) 2. The combination of claim 1, wherein each of said plateaus has a minimum surface area of ​​0.010 square inches. (Item 7) 2. The combination of claim 1, wherein each of the plateaus has a surface area in the range of 0.010 square inches to 0.1 square inches. (Item 8) 2. The combination of claim 1, wherein each of the plateaus has a minimum surface area in the range of 0.020 to 0.075 square inches. (Item 9) Item 2. The combination of item 1, wherein at least one of the raised surfaces has a polygonal cross-sectional shape. (Item 10) 2. The combination of claim 1, wherein at least one of the raised surfaces has a rounded cross-sectional shape. (Item 11) 2. The combination of claim 1, wherein at least one of the raised surfaces is tapered, and the at least one raised surface has a circumference at the plateau that is smaller than a circumference at the base surface. (Item 12) 2. The combination of claim 1, wherein the fastener element is softer than the plurality of raised surfaces. (Item 13) 2. The combination of claim 1, wherein the fastener element comprises steel. (Item 14) 2. The combination of claim 1, wherein the plurality of raised surfaces comprises ductile iron. (Item 15) 1. A coupling for joining pipe elements in an end-to-end relationship, said coupling comprising: a first section having oppositely disposed first and second ends; a second section having oppositely disposed first and second ends; a first fastener attaching the first end of the first section to the first end of the second section; a second fastener attaching the second end of the first section to the second end of the second section such that the sections enclose a central space for receiving the pipe element; a first connecting member and a second connecting member positioned at each of the first end and the second end of each of the first section and the second section, respectively; Each of the connection members comprises: a base surface oriented transversely to one of the fasteners; a plurality of raised surfaces projecting transversely relative to the base surface and engageable with one of the fasteners, each of the raised surfaces comprising a flat area, each of the raised surfaces being separated from at least adjacent ones of the raised surfaces by a channel positioned therebetween; A coupling comprising: (Item 16) Item 16. The coupling of item 15, wherein at least one of the fasteners comprises a threaded nut engageable with one of the raised surfaces. (Item 17) Item 16. The coupling of item 15, wherein at least one of the fasteners comprises a threaded bolt having a head engageable with one of the raised surfaces. (Item 18) Item 16. The coupling of item 15, wherein each of the plateaus has a height of 0.060 inches above the base surface. (Item 19) Item 16. The coupling of item 15, wherein each of the plateaus has a height above the base surface in the range of 0.020 inches to 0.1 inches. (Item 20) Item 16. The coupling of item 15, wherein each of said plateaus has a minimum surface area of ​​0.010 square inches. (Item 21) Item 16. The coupling of item 15, wherein each of the plateaus has a surface area in the range of 0.010 square inches to 0.1 square inches. (Item 22) Item 16. The coupling of item 15, wherein at least one of the raised surfaces has a polygonal cross-sectional shape. (Item 23) Item 16. The coupling of item 15, wherein at least one of the raised surfaces has a rounded cross-sectional shape. (Item 24) Item 16. The coupling of item 15, wherein at least one of the raised surfaces is tapered, the at least one raised surface having a smaller circumference at the plateau than a circumference at the base surface. (Item 25) Item 16. The coupling of item 15, wherein at least one of the fasteners is softer than the plurality of raised surfaces. (Item 26) Item 16. The coupling of item 15, wherein at least one of the fasteners comprises steel. (Item 27) Item 16. The coupling of item 15, wherein the plurality of raised surfaces comprises ductile iron. (Item 28) Item 16. The coupling of item 15, wherein the plurality of raised surfaces are integrally cast with the coupling. (Item 29) A flange mountable on a pipe element, said flange comprising a ring having a contact surface adapted to touch a mating flange, an exposed surface arranged opposite said contact surface, said exposed surface comprising: A base surface; a plurality of raised surfaces projecting transversely relative to the base surface, each of the raised surfaces comprising a plateau, each of the raised surfaces being separated from at least adjacent ones of the raised surfaces by a channel positioned therebetween; A flange comprising: (Item 30) 30. The flange of claim 29, wherein the plurality of raised surfaces extend around the entire exposed surface. (Item 31) 30. The flange of claim 29, wherein at least one of the raised surfaces has a polygonal cross-sectional shape. (Item 32) 30. The flange of claim 29, wherein at least one of the raised surfaces has a rounded cross-sectional shape. (Item 33) 30. The flange of claim 29, wherein at least one of the raised surfaces is tapered, the at least one raised surface having a smaller circumference at the plateau than a circumference at the base surface. (Item 34) 30. The flange of claim 29, wherein each of the plateaus has a height of 0.060 inches above the base surface. (Item 35) 30. The flange of claim 29, wherein each of the plateaus has a height above the base surface in the range of 0.020 inches to 0.1 inches. (Item 36) 30. The flange of claim 29, wherein each of said flat areas has a minimum surface area of ​​0.010 square inches. (Item 37) 30. The flange of claim 29, wherein each of the flat areas has a surface area in the range of 0.010 square inches to 0.1 square inches. (Item 38) 1. A flange coupling for joining pipe elements, said flange coupling comprising: a first ring having a first contact surface and a first exposed surface disposed on opposite sides; a second ring having an oppositely disposed second contact surface and a second exposed surface, the second contact surface contacting the first contact surface; a plurality of fasteners extending through the first and second rings; each of the fasteners comprises at least one rotatable member that engages at least one of the exposed surfaces of one of the rings, the at least one exposed surface comprising: A base surface; a plurality of raised surfaces projecting transversely relative to the base surface, each of the raised surfaces comprising a plateau, each of the raised surfaces being separated from at least adjacent ones of the raised surfaces by a channel positioned therebetween; A flange coupling comprising: (Item 39) Item 39. The flange coupling of item 38, wherein the plurality of raised surfaces extend around the entire exposed surface. (Item 40) Item 39. The flange coupling of item 38, wherein at least one of the raised surfaces has a polygonal cross-sectional shape. (Item 41) Item 39. The flange coupling of item 38, wherein at least one of the raised surfaces has a rounded cross-sectional shape. (Item 42) Item 39. The flange coupling of item 38, wherein at least one of the raised surfaces is tapered, and the at least one raised surface has a smaller circumference at the plateau than a circumference at the base surface. (Item 43) Item 39. The flange coupling of item 38, wherein the at least one rotatable member comprises a threaded nut engagable with at least one of the raised surfaces. (Item 44) Item 39. The flange coupling of item 38, wherein the at least one rotatable member comprises a threaded bolt having a head engageable with one of the raised surfaces. (Item 45) Item 39. The flange coupling of item 38, wherein the at least one rotatable member is softer than the plurality of raised surfaces. (Item 46) Item 39. The flange coupling of item 38, wherein the at least one rotatable member comprises steel. (Item 47) Item 39. The flange coupling of item 38, wherein the plurality of raised surfaces comprises ductile iron. (Item 48) Item 39. The flange coupling of item 38, wherein the plurality of raised surfaces are integrally cast with the at least one exposed surface. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is an isometric view of an exemplary combination of a platform and fastener element according to the present invention.

[0021] [Figure 1A] FIG. 1A is an isometric view of another exemplary combination of a platform and fastener element in accordance with the present invention.

[0022] [Diagram 2] FIG. 2 is an isometric view of components of the example platform element shown in FIG.

[0023] [Diagram 3] FIG. 3 is an isometric view of an exemplary mechanical pipe coupling using a combination platform and fastener element in accordance with the present invention.

[0024] [Figure 4] FIG. 4 is an isometric view of an exemplary flanged coupling using a combination platform and fastener element in accordance with the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] (Detailed Description) One aspect of the present invention is directed to a platform and fastener element combination. An exemplary combination 10 is shown in FIG. 1 and includes a platform 12 that contacts a fastener element 14 (in this example, a threaded nut 16 of a threaded bolt 18). The fastener element 14 may also include a head of a bolt 18 (not shown). As shown separately in FIG. 2, the exemplary platform includes a base surface 20. The base surface 20 is oriented transversely to an axis 22 about which the fastener element is rotatable. A plurality of raised surfaces 24 project transversely relative to the base surface 20. The raised surfaces 24 include respective flat areas 26. Each raised surface 26 is separated from at least one adjacent raised surface by a respective channel 28 positioned therebetween. 1A, the raised surfaces 24 have a polygonal cross-sectional shape in this embodiment, although other shapes are possible and a practical example combination 11 of the platform 12 has raised surfaces 24 with plateaus 26 having a rounded cross-sectional shape. As shown in FIG. 2, the raised surfaces 24 can be tapered such that each raised surface has a smaller perimeter 30 at the plateaus 26 than the base surface 20. A taper angle of about 3° is advantageous for providing a draft angle when the platform is manufactured by a casting process.

[0026] As shown in Figures 1 and 1A, the raised surface 24 contacts the fastener element 14. In this embodiment, the nut 16 is forced against the plateau 26 when rotated relative to the platform 12 about the axis 22, tightening the nut against the fixed bolt 18. It is well known that the tensile stress in the bolt 18 increases as the nut 16 is tightened, and that the torque required to turn the nut also increases as the nut is tightened. However, it has been observed that when the turning nut 16 is forced into contact with the raised surface 24, the torque required to turn the nut increases at a higher rate compared to the increase in bolt stress that would otherwise occur in the absence of the raised surface. This observed phenomenon is in fact advantageous, as it can be used to protect the bolt from damage caused by over-torque.

[0027] 3 illustrates a practical implementation of the combination 10 on a coupling 31 for joining pipe elements (not shown) in an end-to-end relationship. In this embodiment, the coupling 31 comprises a first section 32 having a first end 34 and a second end 36 disposed on opposite sides, and a second section 38 having a first end 40 and a second end 42 disposed on opposite sides. A first fastener 44 attaches the first end 34 of the first section 32 to the first end 40 of the second section 38. A second fastener 46 attaches the second end 36 of the first section 32 to the second end 42 of the second section 38 such that the sections 32 and 38 enclose a central space 48 for receiving the pipe elements. In this embodiment, the fasteners 44 and 46 comprise a mating nut 16 and a bolt 18.

[0028] A first connecting member 50 and a second connecting member 52 are positioned at each of the first and second ends (34, 36, 40, 42) of the first and second sections 32 and 38, respectively. In this embodiment, each connecting member 50, 52 includes a base surface 20, as described above, oriented transversely to a respective fastener (44 or 46) passing through the connecting member. A raised surface 24 projects transversely to each base surface 20 and is engageable with the fasteners 44 and 46. As described above for the combination 10, each raised surface 24 includes a flat area 26, and each raised surface is separated from at least adjacent ones of the raised surfaces by a channel 28 positioned therebetween. Consistent with the combination 10, as described above and shown in FIG. 1, the raised surfaces 24, in this embodiment, have a polygonal cross-sectional shape and are tapered such that each raised surface has a smaller perimeter 30 at its flat area 26 than its base surface 20. In this example, when fasteners 44 and 46 are tightened, nut 16 engages and rotates relative to flats 26 of raised feature 24; however, in other exemplary embodiments, the head of bolt 18 may engage and rotate relative to flats. Although combination 10 is depicted for use with coupling 31, combination 11 of FIG. 1A having flats 26 with a round cross-sectional shape is also feasible in this implementation.

[0029] In a practical embodiment of coupling 31, when used with a standard ASME B18.2.2 thick hex nut of size 1 / 2 inch made from ASTM A563 carbon steel, a significant disproportionate increase in torque compared to the associated increase in bolt stress was observed for plateau 26 having a height of 0.060 inches above base surface 20 and a minimum surface area of ​​0.010 square inches. For a valid design, it is expected that the plateau area will generally increase with increasing fastener size and with increasing nut or bolt contact area. For this design, the phenomenon of disproportionate increase in torque was observed directly by the increase in torque felt when a hand-held wrench was used to tighten the coupling fastener. In tests intended to induce bolt failure, it was observed that when an impact wrench was used, the time to bolt failure increased by a factor of two when a coupling employing the raised feature according to the present invention was tested against a coupling without combination 10.

[0030] It is contemplated that effective designs of combinations 10 and 11 according to the present invention may be achieved with plateaus 26 having heights in the range of 0.020 inches to 0.1 inches above base surface 20, with a height of 0.060 inches being contemplated to be advantageous. Also, practical designs may have surface areas in the range of 0.010 square inches to 0.1 square inches, with a surface area in the range of 0.020 to 0.075 square inches being advantageous. Effective protection of bolts ranging from 0.25 inches to 1 inch in diameter (as well as similar and equivalent metric sizes) is contemplated to be achieved using combinations 10 and 11, etc. according to the present invention.

[0031] In the exemplary coupling 31, the fastener element 14 (nut 16) is formed from carbon steel and has a lower surface hardness than the plurality of raised surfaces 24, which are integrally cast with the coupling and formed from ductile iron. In experimental couplings, it has been observed that as increasing torque is applied to the nut 16, the flat areas 26 have a sacrificial nature and are worn away by the nut 16, and after the flat areas have been significantly worn away, the bolt stress increases significantly.

[0032] 4 shows another practical embodiment in which the combination of platform 12 and fastener element is used on a flange 54 of a flange coupling 56. In this example, the flange coupling 56 comprises a flange 54 in the form of a first ring 58 having an oppositely disposed first contact surface 60 and a first exposed surface 62, and a second ring 64 having an oppositely disposed second contact surface 66 and a second exposed surface 68. The second contact surface 66 touches the first contact surface 60. Typically, a seal 70 is captured between the contact surfaces 60 and 66 to ensure a fluid tight fit.

[0033] A plurality of fasteners 72 extend through the first ring 58 and the second ring 64. Each fastener 72 comprises at least one rotatable member that engages at least one of the exposed surfaces 62, 68 of one of the rings 58, 66. In a practical embodiment, the rotatable member may comprise a threaded nut 74, or a threaded bolt 76 having a head 78, which may engage both exposed surfaces 62 and 68.

[0034] The exposed surface of the flange 54 comprises a base surface 20 and a plurality of raised surfaces 24 projecting transversely relative to the base surface 20, as described above with respect to the platform 12 and the coupling 31. The raised surfaces 24 comprise respective flat areas 26. Each raised surface 26 is separated from at least one adjacent raised surface by a respective channel 28 positioned therebetween. The raised surfaces 24 have a polygonal cross-sectional shape in this embodiment, although other shapes are possible, such as the round shape of FIG. 1A. Additionally, it is advantageous for the raised surfaces 24 to be tapered such that each raised surface has a smaller perimeter 30 at the flat area 26 than the base surface 20. The raised surfaces 24 may have the same or similar height and area dimensions as described above. The raised surfaces may also comprise ductile iron and may be cast integrally with the flange 54. As further described above, the fastener may be softer than the plurality of raised surfaces and may be formed from steel. Bolt stresses are expected to be limited until the plateaus are significantly worn away due to their sacrificial nature.

[0035] 4, the flange coupling 56 may include a first pipe stub 80 and a second pipe stub 82 to which the rings 58 and 64 are attached, respectively. The stub pipes 80 and 82 may be welded to respective pipe pieces (not shown) that have been cut or machined to the desired length, or the rings 58 and 64 may be attached directly to the pipe stock, for example by welding.

[0036] In the flange coupling 56, when the coupling 56 is assembled, the rotatable elements (threaded nut 74 and / or bolt head 78) engage and are forced to rotate relative to the plateau 26. It is expected that the bolts 76 will experience a phenomenon of a disproportionate increase in the torque required to tighten the nut 74 or bolt head 78 compared to the increase in tensile stress within the bolts 76 in response to tightening. This effect is expected to protect the bolts 76 from damage due to excessive torque on the flange coupling 56.

Claims

[Claim 1] The invention described in this specification.

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