Abstract
A self-aligning corner bead for fireproofing structural steel, having a strip of welded wire fabric cut to the appropriate width for the fireproofing thickness and bent longitudinally to form an obtuse V-shaped device is disclosed. A plastic nosing is installed along one edge. A method of finishing the corners for fireproofing of structural steel member using an improved corner bead includes the step of attaching the first wing of an obtuse V-shaped device through a lathe to the structural steel member utilizing pneumatic or screw type fasteners. The mesh structure of the second wing of the V-shaped device provides a dam to form a roughened surface on the first application of fireproofing material until it hardens.
Claims
1. A corner bead for fireproofing a member, comprising: a welded wire fabric; a longitudinal bend integrally formed in the welded wire fabric; a first wing defined by the longitudinal bend; a second wing defined by the longitudinal bend, extending away from the first wing; an adjustable angle between the first wing and the second wing; a fire proofing thickness defined by the adjustable angle along a set of adjacent corner sides of the member; a rigid dam defined by the second wing; and, wherein the welded wire fabric is only fastened to the member at a fastening position on the first wing.
2. The corner bead of claim 1, further comprising a substrate integrally formed in the second wing, opposite the longitudinal bend.
3. The corner bead of claim 2, further comprising a nose formed by the substrate.
4. The corner bead of claim 1, wherein the adjustable angle is in a range from greater than approximately 90 degrees to less than approximately 180 degrees.
5. The corner bead of claim 1, wherein the welded wire fabric comprises: a plurality of longitudinal ribs; a plurality of transverse ribs arranged substantially perpendicular to the plurality of longitudinal ribs; and, a plurality of voids defined by the plurality of longitudinal ribs and the plurality of transverse ribs.
6. The corner bead of claim 1, wherein the first wing is a first flexible strip.
7. The corner bead of claim 1, wherein the second wing is a second flexible strip.
8. The corner bead of claim 1, further comprising a set of generally planar surfaces defined by the second wing.
9. The corner bead of claim 1, wherein the rigid dam extends longitudinally along the member.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1 is a perspective view of a small section of a corner bead according to the prior art.
(2) FIG. 2 is a cross-sectional schematic view of a fireproofing structure utilizing a prior art corner bead installed according to a contour method.
(3) FIG. 3 is a perspective view of an exemplary small section of the corner bead of the present invention bent along a longitudinal axis and manufactured according to an embodiment of the present invention.
(4) FIG. 4 is an enlarged cross-sectional schematic view of the self-aligning, double wire corner bead of the present invention.
(5) FIG. 5 is a cross-sectional schematic view of a fireproofing structure utilizing a self-aligning, double wire corner bead of the present invention according to the contour method.
(6) FIG. 6 is a perspective view of a small section of the corner bead manufactured according to one of the embodiments of the present invention.
(7) FIG. 7 is a cross-sectional schematic view of the fireproofing structure utilizing a corner bead of the present invention according to the hollow-box method.
(8) FIG. 8 is a cross-sectional schematic view of the fireproofing structure utilizing a corner bead of the present invention according to the contour method.
DETAILED DESCRIPTION
(9) Referring to FIG. 3, corner bead 10 includes a plurality of longitudinal ribs 16 arranged substantially parallel with respect to a plurality of longitudinal axes, including longitudinal axis A and to each other, and a plurality of transverse ribs 18 distributed between and extending substantially perpendicular to the plurality of longitudinal axes and the plurality of longitudinal ribs 16. A set of void areas 20 is defined by the plurality of longitudinal ribs 16 and the plurality of transverse ribs 18, such that each void area 20 is bounded by at least two longitudinal ribs 16 and at least two transverse ribs 18. A section of corner bead 10 includes a single strip of welded wire fabric cut to a predetermined length L and a predetermined width W. The predetermined length L and the predetermined width W correspond to a predetermined fireproofing thickness.
(10) In a preferred embodiment, corner bead 10 is made of a suitable metal, such as 16 gauge wire. Other suitable materials known in the art may be employed, including suitable plastics. In a preferred embodiment, corner bead 10 is a double welded wire fabric.
(11) In a preferred embodiment, corner bead 10 has a set of bends integrally formed in corner bead 10 along the plurality of longitudinal axes. Any number of bends may be employed. Longitudinal axis A defines first wing 12 and single wire membrane 11. First wing 12 and single wire membrane 11 form angle at of approximately greater than 90 degrees, but less than approximately 180 degrees as further illustrated in FIGS. 4 and 5. A set of edges of first wing 12 defines a substrate to which nose 14 is attached. Nose 14, first wing 12, and second wing 12 (shown in FIG. 5) provide a rigid edge having a dam-like function, as will be further described below.
(12) In a preferred embodiment, nose 14 is made of a suitable plastic, such as polyvinyl chloride. Other suitable materials known in the art may be employed.
(13) Referring to FIG. 4, corner bead 10 is bent along a plurality of longitudinal lines 41, 42, 43, and 44, to provide a substantially continuous profile having a plurality of dihedral angles. Longitudinal line 44 defines first wing 12 and single wire membrane 11 extending laterally therefrom at angle .sub.1. Angle .sub.1 is approximately greater than 90 degrees, but less than approximately 180 degrees. Each of noses 14 is attached to first wing 12 and second wing 12. Longitudinal line 42 defines single wire membrane 11 and leg 31 of double wire membrane 30 extending from single wire membrane 11 in a continuous manner. Single wire membrane 11 and leg 31 are separated by angle . Angle is approximately 90 degrees. Longitudinal line 43 defines leg 31 of double wire membrane 30 and leg 31 of double wire membrane 30. Leg 31 is positioned substantially parallel to leg 31. Leg 31 substantially overlaps leg 31. Longitudinal line 41 defines second wing 12 and leg 31 of double wire membrane 30. Leg 31 extends away from second wing 12 at angle .sub.2. Angle .sub.2 is approximately greater than 90 degrees, but less than approximately 180 degrees.
(14) In use, the improved, self-aligning, double wire corner bead 10 of the present disclosure is utilized in a contour-like manner, surrounding a structural steel member with fireproofing material. Referring to FIG. 5, double wire corner bead 10 is secured to structural steel member 24. First wing 12 is configured to establish a desired thickness of fireproofing material 22 along two surfaces of the structural steel member by providing a rigid screed edge to which nose 14 is attached. Double wire membrane 30 is secured to structural steel member 24, as will be further described below. Fireproofing material 22 surrounds the dimensions of the structural steel member 24 in a contour-like manner, tracing structural steel member 24 in all dimensions. The single strip of corner bead 10 allows uniform distribution of fireproofing material 22 along three surfaces, surfaces S.sub.1, S.sub.2, and S.sub.3.
(15) Referring to FIGS. 4 and 5, the width of the wings 12 and 12 determines distances D.sub.1, D.sub.2, and D.sub.3, and defines generally planar surfaces S.sub.1, S.sub.2, and S.sub.3 forming a set of corners of fireproofing material 22 distributed around structural steel member 24. Similarly, any of distances D.sub.1, D.sub.2, and D.sub.3 are optionally altered by changing angles .sub.1 and .sub.2. Angles .sub.1 and .sub.2 are substantially equal and measure approximately greater than 90 degrees, but less than 180 degrees. Angle measures approximately 90 degrees. For example, the smaller (less obtuse) angle .sub.1 is between first wing 12 and the single wire membrane 11 the longer distance D.sub.1 is between lath 26 and surface S.sub.1, and the shorter distance D.sub.3 is between lath 26 and surface S.sub.2. Similarly, the less obtuse angle .sub.2 is between second wing 12 and leg 31 of double wire membrane 30, the longer distance D.sub.2 is and the shorter distance D.sub.1 is making distributed fireproofing material 22 thicker along surface S.sub.3 in relation to a thinner strip of fireproofing material 22 along surface S.sub.1.
(16) In a preferred embodiment, the determination of angles .sub.1 and .sub.2 should be such that a uniform thickness of fireproofing material 22 along surface S.sub.1 is achieved.
(17) In one embodiment, lath 26 is distributed around structural steel member 24. Single wire membrane 11 is attached through lath 26 into structural steel member 24 by pneumatic fastener 28 at a single fastening position on single wire membrane 11. Other joining or attaching means known in the art, such as welded pins or screws, may be employed.
(18) In another embodiment, each of single wire membrane 11 and double wire membrane 30 is attached to structural steel member 24 by pneumatic fastener 28 at a single fastening position on double wire membrane 30.
(19) In another embodiment, leg 31 and leg 31 of double wire membrane 30 are attached through lath 26 into structural steel member 24 by pneumatic fastener 28 at a single fastening position on double wire membrane 30. Other joining or attaching means known in the art, such as welded pins or screws, may be employed. According to one embodiment of the present invention, lath 26 is optionally distributed along the entire perimeter of structural steel member 24 to be fireproofed (not shown). In another embodiment, lath 26 is distributed along a portion of the perimeter of structural steel member 24.
(20) In other embodiments, any number of fastening positions and locations may be employed.
(21) The width of first wing 12 and second wing 12 along with nose 14 attached to the outer edges of both wings serves as a dam during the process of fireproofing. Fireproofing material 22 is then sprayed onto lath 26 and screened off using the location of nose 14 to determine the finished thickness of fireproofing material 22.
(22) Referring to FIG. 5, in a shop application, i.e., fireproofing material 22 is applied to structural steel member 24 in a pre-fabrication facility, the cementitious composition is sprayed or poured one layer at a time on a surface of lath 26 positioned horizontally. Structural steel member 24 is then rotated 90 degrees and the adjacent surfaces are positioned horizontally to allow easy application of fireproofing material 22. With this process in place, each successive spraying is performed which allows hardening of fireproofing material 22 before the next rotation of structural steel member 24. As can be seen, the dam-like functionality of corner bead 10 according to one embodiment of the present invention is critical as it provides an appropriate keying surface to bond the subsequent layers of fireproofing material 22. Each structural steel member 24 is turned to uniformly apply the cementitious material to all surfaces.
(23) It will be appreciated by those skilled in the art that any type of member may be employed.
(24) In a field application on a job site, structural steel members 24 are erected into a structure prior to fireproofing, and all surfaces of structural steel member 24 may be sprayed or troweled onto the surface of lath 26 at the same time (not shown).
(25) Referring to FIG. 6 in another embodiment, a corner bead structure comprising a strip of welded wire fabric 610 cut to the appropriate length L2 and width co for the fireproofing thickness and bent longitudinally to form a structure having a longitudinal axis A.sub.2, said longitudinal axis to define a first wing 611 and a second wing 612, said first wing 611 and said second wing 612 forming an angle of approximately more than 90 degrees but less than approximately 180 degrees. The second wing's outer edge comprises a substrate forming a nose 614, said nose 614 together with the second wing 612 providing a rigid edge of dam-like functionality.
(26) As further shown in FIG. 6, the corner bead structure (typically 16 gauge welded wires) comprises a plurality of longitudinal metal ribs 616 arranged in substantially parallel fashion to the longitudinal axis A.sub.2 and to each other and the plurality of transverse metal ribs 618 disposed between and extending substantially perpendicular to the longitudinal axis A.sub.2 and the longitudinal metal ribs 616. A plurality of void areas 620 of the approximate size 0.50.5 are disposed between the longitudinal ribs 616 and the transverse ribs 618, such that each said void area 620 is bounded by at least two longitudinal ribs 616 and at least two transverse ribs 618.
(27) In general, two methods of enveloping the structural steel member with the fireproofing material may be utilized. As shown in FIG. 7, the cementitious fireproofing material 622 surrounds the dimensions of the structural steel in a hollow-box manner, leaving empty void areas 624 between the structural steel member 626.
(28) As shown in FIG. 8, the cementitious fireproofing material 622 surrounds the dimensions of the structural steel member 626 in a contour-like manner, tracing the structural steel member 626 in all its dimensions.
(29) As can be seen most clearly in FIGS. 7 and 8, the second width W2 of a second wing 612 determines the distances (D.sub.1 and D.sub.2) between the lath 628 disposed over the structural steel member 626 and the two planar surfaces, S.sub.1 and S.sub.2 forming a corner of the fireproofing material 622 disposed around the structural steel member 626. Similarly, the distances, D.sub.1 and D.sub.2, may be altered by changing an angle at which the strip of the welded material with pre-determined width is bent along its longitudinal axis A.sub.2. For example, the smaller (less obtuse) the angle between the first wing 611 and the second wing 612, the longer is the distance D.sub.1 between the lath 628 and the surface S.sub.1, and the shorter is the distance D.sub.2 between the lath 628 and the surface S.sub.2. Consequently, such change in the angle causes the strip of the fireproofing material 622 to be thicker along surface S.sub.1 in relation to the thickness of the fireproofing strip 622 along surface S.sub.2.
(30) In a further development of the subject matter described with reference to FIGS. 6, 7, and 8, the first wing 611 is attached through the lath 628 into the structural steel member by the pneumatic fastener 630. Other contemplated joining (attaching) means are welded pins or screws. The second wing 612 along with the plastic nose 614 attached to the outer edge of the second wing 612 serves as a dam during the process of fireproofing. The fireproofing material is then sprayed onto the lath 628 and screeded off using the plastic nose's 614 location to determine the finished thickness of the fireproofing material.
(31) In a shop application (i.e., fireproofing is applied in a facility of the applicant to individual steel members), the cementitious composition is sprayed or poured one at a time on one horizontal surface 632 of lath 628 as shown in FIG. 7. The steel member 626 is then rotated 90 degrees and the adjacent surfaces become horizontal to allow easy application of the fireproofing material. With this process in place, each successive spraying is performed which allows hardening of the fireproofing material before the next rotation of the steel member. This is why the dam-like functionality of the corner bead according to one embodiment of the present invention is critical as it provides an appropriate keying surface to bond the subsequent layers of the fireproofing material. Each steel member is turned four times to uniformly apply the cementitious material to all surfaces.
(32) In a field application (outside of applicant's facility), where the members are erected into a structure prior to fireproofing, all surfaces of the steel member may be sprayed or troweled onto the lath surfaces at the same time (not shown). The process is similar regardless of whether the contour or hollow-box application is utilized.
(33) It will be appreciated that the invention is not restricted to the particular embodiment that has been described, and that variations may be made therein without departing from the scope of the invention as defined in the appended claims, as interpreted in accordance with principles of prevailing law, including the doctrine of equivalents or any other principle that enlarges the enforceable scope of a claim beyond its literal scope. Unless the context indicates otherwise, a reference in a claim to the number of instances of an element, be it a reference to one instance or greater than one instance, requires at least the stated number of instances of the element, but is not intended to exclude from the scope of the claim a structure or method having more instances of that element than stated. The word comprise or a derivative thereof, when used in a claim, is used in a nonexclusive sense that is not intended to exclude the presence of other elements or steps in acclaimed structure or method.
