PARTITION STUD

Abstract

A metal stud comprising a web and flanges extending perpendicularly from respective edges of the web and each having a stiffening return, the web comprising a longitudinal rib at each edge thereof, each rib having a width of 0.250″ from a respective edge of the web and a depth of 0.060″ from a baseline of the web.

Description

FIELD OF THE INVENTION

The present invention relates to partition studs. More specifically, the present invention is concerned with metallic partition studs.

BACKGROUND OF THE INVENTION

Studs are vertical framing members used in building walls. In the case of inner walls, referred to as partition walls, the studs typically hold in place doors and interior finish. As shown in FIG. 1, studs run from a bottom track (B) to a top track (not shown in FIG. 1). Wall materials and/or wall boards or panels (P) are then secured to the flanges 12 of the studs, using screws (S) for example, to form a closed partition wall structure.

In North America, studs were traditionally made of wood, usually 2″×4″ or 2″×6″ dimensional lumbers and typically placed 16 inches (406 mm) from each other's center, but sometimes also at 12 inches (305 mm) or 24 inches (610 mm). The wood needs to be dry when used or problems may occur as the studs shrink and twist as they dry out.

Metallic studs, such as steel studs, are gaining popularity, especially for non-load-bearing walls, and are required in some firewalls. A metal stud is formed from a sheet of metal, preferably between about 0.015 and about 0.040 inches in thickness, which is folded into a C-shape cross section to provide a central web 16 disposed perpendicular to the general plane of the partition (P), and a pair of L-shaped flanges 12 extending perpendicularly from the two respective edges of the web 16 and having a stiffening return 14 extending perpendicularly inwardly from the edge of each flange 12 opposite to the edge thereof joining the web 16 (see FIG. 1). The flanges 12 are for attachment of wall materials and/or wall boards or panels (P) to form the closed wall structure as described hereinabove.

The stiffness or stability of a resulting partition is a function of many factors in the stud design and the partition design.

Since the early 50s′, efforts have been made so as to increase resistance of the metal studs to compressive load for example. Thus for instance, wider returns 14 have been used, but their width is limited by buckling of the metal forming the stud. Strengthening has been increased by stamping or knurling the outer surface of the flanges 12 and/or of the web 16. Selecting harder steels and/or increasing the thickness of the metal allow achieving stronger studs but make it more difficult to screw or nail therethrough and may result in more expansive and/or heavier studs.

There is still a need in the art for metal studs.

SUMMARY OF THE INVENTION

More specifically, in accordance with the present invention, there is provided a metal stud comprising a web and flanges extending perpendicularly from respective edges of the web and each having a stiffening return, the web comprising a longitudinal rib at each edge thereof, each rib having a width of 0.250″ from a respective edge of the web and a depth of 0.060″ from a baseline of the web.

There is further provided a method for making a metal stud from a sheet of metal, comprising forming a longitudinal rib at each edge of the sheet, and folding the sheet into a general C-shape section, with a central web connected at each edge thereof to a flange and provided with a longitudinal rib at each edge of the central web.

There is further provided a method for reinforcing a metal stud comprising a web and flanges extending perpendicularly from respective edges of the web, the method comprising providing a longitudinal rib at each edge of the web, each rib having a width of 0.250″ from a respective edge of the web and a depth of 0.060″ from a baseline of the web.

Other objects, advantages and features of the present invention will become more apparent upon reading of the following non-restrictive description of specific embodiments thereof, given by way of example only with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the appended drawings:

FIG. 1 shows studs as known in the art;

FIG. 2 shows a stud 1⅝″×1¼″ according to an embodiment of an aspect of the present invention;

FIG. 3 shows a stud 2½″×1¼″ according to an embodiment of an aspect of the present invention;

FIG. 4 shows a stud 3⅝″×1¼″ according to an embodiment of an aspect of the present invention;

FIG. 5 shows a stud 4.000×1¼″ according to an embodiment of an aspect of the present invention;

FIG. 6 shows a stud 6.000″×1¼″ according to an embodiment of an aspect of the present invention;

FIG. 7 shows a perspective view of a stud according to an embodiment of an aspect of the present invention;

FIG. 8 compares heights permitted with studs of the present invention in a galvanized steel of a thickness of 0.017, and with corresponding studs of the prior art; and

FIG. 9 compares heights permitted with studs of the present invention in galvanized steel of a thickness of 0.021, and with corresponding studs of the prior art.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Studs according to embodiments of aspects of the present invention are shown for example in FIG. 2-7.

The partition studs 10, 10′, 10″, 10′″ and 10″″ have a general C-shape section, with a web 16 and a pair of L-shaped flanges 12 each having a return 14 at a free end thereof. Connection between each flange 14 and the web 16 is done with a radius of curvature R.

As illustrated in FIG. 7, the outer surface of the flanges 12 may be provided with knurling.

As best seen in FIGS. 2-6, the web 16 comprises a longitudinal rib 18 at each extremity thereof, running generally along the length of the web 16 (i.e. perpendicularly to the views of FIGS. 2-6).

As illustrated in FIG. 2-6 for studs made in a galvanized steel of a thickness of 0.017 or 0.021′, each rib 18 has a width w, from the junction between a flange 12 and the web 16, i.e. from the outer edge of the web along a width of the web 16, of 0.250″, and a depth d of 0.060″ from the baseline of the web 16. The flanges 12 have a width W_f of 1.250″, the returns 14 have a width W_r of 0.250″ and the radius of curvature R at the junction between the web 16 and each flange 12 is 0.040″. The connecting angle between the rib 18 and the baseline of the web 16 is of 45 degrees, as shown in FIG. 2 for example.

A steel with a yield strength of at least 33 ksi is selected For example, a galvanised steel having a yield strength of 50 ksi was used with a thickness of 0.021″, and a galvanised steel having a yield strength of 33 ksi with a thickness of 0.0017′ was used.

In FIG. 2, the stud 10 has a width W₁, generally determined by the width of the web 16, of 1.625′″. In FIG. 3, the stud 10′ has a width W₂ of 2.500′″. In FIG. 4, the stud 10″ has a width W₃ of 3.625′″. In FIG. 5, the stud 10′″ has a width W₄ of 4.000′″. In FIG. 6, the stud 10″″ has a width W₅ of 6.000′″.

A coating on the steel may be used for anticorrosion purposes as known in the art.

A specific combination of rib geometry and position of the ribs 18 is found to enhance the compressive strength of the resulting stud and hence the limiting partition heights permitted using them, as follows:

Yield strength of 33 ksi or 50 ksi with a thickness of 0.017″ or 0.021″ respectively.

Stud width W (inside dimensions): 1⅝″, 2½″, 3⅝″, 4″ and 6″.

Flange size W_f: 1″¼.

Return size: W_r: ¼″.

Tests were performed on composite wall assemblies comprising 0.017″ and 0.021″ thick cold-formed steel studs of the present invention and ⅝″ thick type X gypsum wallboards (P), following the requirements of ICC AC86-12, Acceptance Criteria for Cold Formed Steel Framing Members-Interior Nonload-bearing Wall Assemblies, so as to establish limiting height tables for this type of composite wall assembly.

FIGS. 8 and 9 show limiting heights thus allowed with studs of the present invention, as compared with studs of the prior art with a same thickness and yield strength of the steel plate used, submitted to a same pressure (5 psf-pound-force per square foot), for different spacings between consecutive studs (i.e. 12′, c.c/16″ c.c and 24″c.c), as measured according to standard CSA S136:2001 for Cold Formed Steel Structural Members. Unexpected results were obtained with the studs of the present invention. The performances of the studs of the present invention are much greater than could have been predicted by someone of skill in the art based on known studs, in a much unpredictable art, as far as metal behavior in combination to shape and properties is concerned.

There is thus provided an ingenious metal stud formed from a metal sheet folded into a C-shape cross section, of standard overall dimensions, combining a central web and flanges extending perpendicularly from the two respective edges of the web and each having a stiffening return, the central web comprising a longitudinal rib at each edge thereof, each rib having a width of 0.250″ from the edge of the web and a depth of 0.060″ from the baseline of the web.

There is provided a method for reinforcing a metal stud, comprising providing the central web thereof with a rib running longitudinally along each edge thereof, each rib having a width of 0.250″ from the edge of the web and a depth of 0.060″ from the baseline of the web.

The scope of the claims should not be limited by the embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.

Claims

1. A metal stud, comprising a web and flanges extending perpendicularly from respective edges of the web and each having a stiffening return, the web comprising a longitudinal rib at each edge thereof, each rib having a width of 0.250″ from a respective edge of the web and a depth of 0.060″ from a baseline of the web.

2. The metal stud of claim 1, formed from a metal sheet.

3. The metal stud of claim 1, formed from a sheet of a metal having a yield strengths of 33 ksi or 50 ksi with a thickness of 0.017″ or 0.021″ respectively.

4. The metal stud of claim 1, formed from a sheet of a material having a yield strength of 33 ksi or 50 ksi with a thickness of 0.017″ or 0.021″ respectively, wherein said flanges have a width of 1″¼ and said returns have a width of ¼″.

5. The metal stud of claim 1, formed from a sheet of a material having a yield strength of 33 ksi or 50 ksi with a thickness of 0.017″ or 0.021″ respectively, wherein said material is a steel.

6. The metal stud of claim 1, formed from a sheet of a material having a yield strength of 33 ksi or 50 ksi with a thickness of 0.017″ or 0.021″ respectively, wherein said material is a steel comprising an anticorrosion coating.

7. The metal stud of claim 1, said web having a width of 1.625′″, 2.500′″, 3.625′″, 4.000′″ or 6.000′″.

8. The metal stud of claim 1, formed from a sheet of a material having a yield strength of 33 ksi or 50 ksi with a thickness of 0.017″ or 0.021″ respectively, wherein said flanges have a width of 1″¼, said returns have a width of ¼″ and a radius of curvature at a junction between the web and each flange is 0.040″.

9. The metal stud of claim 1, wherein a connecting angle between each rib and the baseline of the web is about 45 degrees.

10. The metal stud of claim 1, wherein the flanges are provided with knurling.

11. A method for making a metal stud from a sheet of metal, comprising forming a longitudinal rib at each edge of the sheet, and folding the sheet into a general-shape section, with a central web connected at each edge thereof to a flange, and provided with a longitudinal rib at each edge of the central web.

12. A method for reinforcing a metal stud comprising a web and flanges extending perpendicularly from respective edges of the web, said method comprising providing a longitudinal rib at each edge of the web, each rib having a width of 0.250″ from a respective edge of the web and a depth of 0.060″ from a baseline of the web.