Abstract:
A metal building stud having at least one supplemental flange extending from at least one slot in the stud web yielding a stud with increased strength, both compressive (longitudinally) and in shear (transverse). The slotted web presents a reduced web area through which heat or sound may be conducted and slots in which insulation is received, both increasing resistance to heat and sound transfer. Slots and supplemental flanges may also be provided in the stud primary flanges.

Description:
BACKGROUND  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates to steel studs comprising parallel flanges extending orthogonally from web sides, and more particularly to a stud with at least one slot in the web and including supplemental flanges extending from slot sides within the web.  
         [0003]     2. Prior Art  
         [0004]     Interior wall construction using horizontal channel beams as headers and footers and matching vertical studs received into the channel beams is well-known. Commonly, the studs are also channel-shaped and both are made of metal, typically cold formed metal and, typically steel. Similarly, metal buildings employ girts (sidewall bracing) and perlins (roof bracing). Roof rafters, headers, footers, beams and joists can also employ channel shaped members. (For purposes herein, use of the term “stud,” “metal stud,” “steel stud” and “building stud” are not meant to be restrictive or limitations but are meant generically to be synonymous and to include all materials from which such studs may be formed.)  
         [0005]     Of all modes of failure, buckling (Euler or local) is probably the most common and most catastrophic. That is, a structure may fail to support a load when a member in compression buckles, that is, moves laterally and shortens in length. A steel stud may be described for these purposes as a slender column where its length is much greater than its cross-section. Euler&#39;s equations show that there is a critical load for buckling of a slender column. With a large load exceeding the critical load, the least disturbance causes the column to bend sideways, as shown in the inserted diagram, which increases its bending moment. Because the bending moment increases with distance from a vertical axis, the slight bend quickly increases to an indefinitely large transverse displacement within the column; that is, it would buckle. This means that any buckling encourages further buckling and such failure becomes catastrophic. 
         
 
         [0006]     The traditional steel stud construction comprises a pair of parallel flanges extending orthogonally from a web. Commonly the flange distal end bends inward slightly to increase the compressive stability converting the flat two-dimensional flange into a three dimensional structure. For these purposes, “compressive stability, strength or stress” means a reference value that measures the load a structure can sustain before it buckles or otherwise deforms and loses support for a load.  
         [0007]     Such studs are very poor energy conservers. For example, for internal walls the metal stud acts as a thermal conduit and actually enhances thermal conductivity across the wall over wood and other materials. In metal buildings the studs (girts and perlins) are in direct metal-to-metal contact with the outside material sheeting and become conduits of heat on the outside sheeting to inside the building. Heat passes through the web, so one interested in reducing thermal conductive might consider removing material from the web to create slots in the web. To the extent such slots remove metal and thus reduce the thermal path, the stud is less conductive thermally. Also, such slots may receive insulation that further impede conductivity.  
         [0008]     Similarly, a steel stud is a good acoustic conductor, which is detrimental in many applications. It has long been desired to reduce sound transmission through metal wall studs. As in thermal conductivity, re-shaping of a significant portion of the web or the flanges will reduce the acoustic conductivity of the stud and therefore the wall.  
         [0009]     It is a primary object of the present invention to enhance the compressive stability, strength and bending resistance of a traditional steel stud. It is another object to reduce thermal conductivity and acoustical transmission, of the stud while enhancing the bending resistance and compressive stability and strength. To this end, it is a further object to introduce one or more slots in the stud web that interrupt conductivity across the web in combination with projections from the web at the slots additional to the primary flanges that enhance the load that a stud can support under bending and compression.  
       SUMMARY  
       [0010]     These objects are achieved in a first embodiment in a building stud having at least one supplemental flange of a substantial I areaI dimension extending from a side of a corresponding slot in the web. These objects are also achieved in a second embodiment in a building stud having a plurality of small holes punched in the stud leaving punched web or flange material projecting from the punched hole.  
         [0011]     These supplemental flanges are formed by stamping out a flange in the web on three flange sides and then bending the supplemental flange away from the web on the fourth, uncut side, forming a slot in the web. The result then is a supplemental flange extending from the web at the slot edges. Typically, the supplemental flange usually extends normal to the web and parallel to the primary flanges extending from the web edges, although it can be angled from the web other than normal. The slot in the stud web presents a reduced web area through which heat or sound may be conducted.  
         [0012]     The flange is formed as the slot is formed by cutting the web for the slot, dividing the intended slot area of the web into two equal side by side panels in the center and top and then folding the panels out from the plane of the web simultaneously forming the slot and a continuous supplemental flange. Alternatively, the slot area can be cut (stamped) with a U cut at the slot top and an inverted U at the slot bottom joined by a center cut between them. The top and bottom U panels are then folded outward to form horizontal supplemental flanges at the slot top and bottom and the side panels are folded out to form vertical supplemental flanges.  
         [0013]     Rather than weaken the stud at the slot, the stud is in fact strengthened through a few mechanisms. First, the longitudinal extent of the web of a traditional stud presents a large vertical plane susceptible to local shear buckling under load that can lead to Euler bucking. Introducing slots having supplemental flanges into the web reduces that extent. That is, the Supplemental Flange Metal Stud (“SFMS”) itself actually stiffens the web plane by creating smaller flat planes in the web plane than are present in standard steel studs thus increasing local shear buckling resistance.  
         [0014]     The calculation discloses that for vertical loading the SFMS provides better stability in buckling resistance due to the center of gravity being moved away from the plane of the web toward the opening of the channel section. This effect distributes the vertical load more uniformly over the SFMS cross-sectional area; rather than mostly in the web as standard steel studs do; and thus forcing local buckling effects to require a higher vertical loading than standard steel studs can handle. The SFMS also enhances resistance to Euler buckling (long column lateral deflection) by the new properties the supplemental flanges provide. In short, for the stud to bend at the slot, both the supplemental and primary flanges orthogonal to the web must also bend, but with the supplemental flanges, there is increased resistance to that bending.  
         [0015]     The supplemental flange can be either continuous (fully encompassing the slot) or discontinuous (not completely encompassing the slot) although the former will provide for greater strength and structural stability than the latter. When all the original material in a traditional metal stud remains in the final SFMS product, in the case of supplemental flanges extending from the full length of slot sides the SFMS retains more than the total cross-sectional area of the traditional stud, which retains its support for compressive loads and provides additional rigidity that equates to better stud stability than traditional steel studs. This is demonstrated in both the x-axis and y-axis bending calculations below.  
         [0016]     Calculations confirm that adding the supplemental flange to the flange at the slot sides and ends not only fully offsets any loss of compressive strength caused by the slot but actually increases it over the unmodified stud without slots or supplemental flanges. That is, the stud can sustain a greater compressive, or longitudinal, or bending load with slots and supplemental flanges than without them. The following calculation is typical:  
         [0017]     The following calculation assumes a 16 gauge “C”-Section Channel, 6″×2½″ (0.0598″ wall thickness) stud.  
         [0018]     The strength of a load supporting column can be represented by the moment of inertia about the major axis, X-X, where buckling could occur first. When the moment reaches a high enough value, known as the Euler Buckling under load the column will buckle. This value is proportional to the moment of inertia, so the higher the moment of inertia, the more load the column will sustain before buckling.  
         [0019]     The following equation calculates the moment of inertia (in 4 ) about the X-X axis for a channel cross-sectional area. The designated sections are as represented in  FIG. 27 .  
         I     x   -   x       =       2   ⁢     (       A   1     ⁢     d   1   2       )       +     2   ⁢     (       A   2     ⁢     d   2   2       )       +     2   ⁢     (       bh   3     12     )       +     2   ⁢     (       A   3     ⁢     d   3   2       )       +     2   ⁢     (       A   4     ⁢     d   4   2       )             
 
 where 
    h=0.0598 inch, the thickness of 16-gauge cold formed steel.     b=width of various sections. For the calculation of I x-x , it will be determined from a central axis between the two widths, 2.50 inches, 1.00 inch, and perpendicular to the 0.375 inch dimension. For the calculation of I y-y , it will be determined by an axis transverse to the two width dimensions, 2.50 inches, 1.00 inch, and parallel to 0.375 inch dimension.     d=distance (in) from the neutral axis to each centroid of an area “A”, respectively.    
 
         [0023]     The neutral axis is located at the centroid or center of gravity, CG, of the stud. It is determined using the equation, 
 
CG y-y   i =yA i /A t  
 
         [0024]     where A i  represents the cross-sectional area of each area that makes up the total cross-sectional area, A t .  
                                             TABLE 1                       Component   A, area (in 2 )   y (in)   yA (in 3 )                                A-1   0.0598)(2.5( )2 = 0.2990   1.25   0.374       A-2   (0.0598)(1)2 = 0.1196   0.5   0.0598       A-3   (0.0598)(2)(2) = 0.2392   0.0299   0.0072       A-4   (0.0598)(0.375)2 = 0.0449   2.5   0.1123       Totals   A  t  = 0.7027       yA  i   = 0.5533                  
 
         [0025]     Using the values in the Table 1 to compute CG, CG y-y =yA/A=(0.5533)/(0.7027)=0.7868 inch from the inside face of web. With this information the values for I x-x  and I y-y  of the supplemental flange stud can be calculated.  
         I     x   -   x       =         2   ⁢     (       A   1     ⁢     d   1   2       )       +     2   ⁢     (       A   2     ⁢     d   2   2       )       +     2   ⁢     (       bh   3     12     )       +     2   ⁢     (       A   3     ⁢     d   3   2       )       +     2   ⁢     (       A   4     ⁢     d   4   2       )         =         2   ⁢     (   0.0598   )     ⁢     (   2.5   )     ⁢       (   2.9701   )     2       +     2   ⁢     (   0.0598   )     ⁢     (   1.0   )     ⁢       (   1.0   )     2       +     2   ⁢     (         (   0.0598   )     ⁢       (   2.0   )     3       12     )       +     2   ⁢     (   0.1196   )     ⁢       (   2   )     2       +     2   ⁢     (   0.0224   )     ⁢       (   2.8125   )     2         =     4.15   -       inch   4     .               
 
 To determine the percentage increase in load that the stud with supplemental flanges can sustain, we next compute the moment of inertia about the major X-X axis of a standard steel stud (without the advantage of the supplemental flanges). Substituting the values as before.  
         I     x   -   x       =           (       bh   3     12     )     SS     +     2   ⁢     Ad   SS   2       +     2   ⁢       (       bh   3     12     )     SS       +     2   ⁢     Ad   SS   2         =         (       0.0598   ⁢       (   6.0   )     3       12     )     +     2   ⁢     (   0.0598   )     ⁢     (   2.5   )     ⁢       (   3.0   )     2       +     2   ⁢     (       0.0598   ⁢       (   0.375   )     3       12     )       +     2   ⁢     (   0.0598   )     ⁢     (   0.375   )     ⁢       (   2.8125   )     2         =     3.23   -       inch   4     .               
 
         [0026]     The percentage improvement in the stud with supplemental flanges is [(4.15-3.23)/(4.15)](100), or 22.3% stronger than an equivalent Standard Steel Stud.  
         [0027]     It has also been determined that resistance to local shear deflection of the stud is also enhanced for the slotted stud with supplemental flanges extending from the web at slot sides. That is, the stud with supplemental flanges also supports a greater lateral load, or a load placed intermediate a nonvertical stud directly on the web, on a slotted metal stud with supplemental flanges than on a metal stud without these features.  
         [0028]     Though the stud is structurally enhanced by the supplemental flanges as discussed above, perhaps the most advantageous contribution of the supplemental flanges is that the web can be slotted without diminishing the structural integrity of the stud, and in fact providing an enhanced structure. The slots interrupt heat (and acoustical) flow through the web across the wall employing the stud. Prior to the described slotted stud with supplemental flanges, metal studs were disfavored because they are a poor insulator; in fact, they are a good insulator, defeating efforts for energy conservation and noise containment. Wood remained the preferred stud material because of the low conductivity of wood. The “R” factor for wood (fir, pine, and spruce) for a 2″×6″ stud is 361 K/w. [1 W/mK=0.578 BTU/Hr-ft-° F.]. The “R” factor for a steel same-sized slotted stud is 846 K/W. The rate of heat loss through the wood stud is 0.055 W and through the slotted steel stud is 0.024 KIW, or less than half. The steel stud immediately becomes competitive and even advantageous. In addition, instead of air in the slot, which conveys heat by convection, insulation can be added. Typically, a wall of slotted studs as described is insulated with insulation foam filled between the studs. The foam is liquid when blown into the wall studded and flows through the slots into several areas between the studs. When the foam dries, the foam not only fills the area between and within the studs but the foam also remains through the stud slots, preventing air flow and consequent thermal transfer by convection as well as by conduction. The slotted stud enhanced structurally by the supplemental flanges and thermally by the slots and insulation in the slots thus becomes an attractive wall construction alternative.  
         [0029]     It is clear that the open slot left in the SFMS that is created by the supplemental flange manufacturing process can vary in width and length depending on the requirements needed from the SFMS. Changes in this width and length will affect the various geometric properties 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0030]      FIG. 1  is a perspective view of the metal stud slots longitutudinal in the web and supplemental flanges extending from the siols sides, shown in a wall extending vertically between floor and ceiling joists.  
         [0031]      FIG. 2  is a rear perspective view of a metal stud with a slotted web having supplemental flanges extending inward from the web between stud parallel primary flanges.  
         [0032]      FIG. 3  is a front perspective view of a metal stud of  FIG. 1 .  
         [0033]      FIG. 4A -F are front views and rear perspective cut-away views of metal studs with a web with one or more slots aligned vertically in the web, the slots shown as circular or oblong shapes, each with a supplemental flange continuous around each slot perimeter.  
         [0034]      FIG. 5  is a front perspective view of a metal stud with a slotted web having supplemental flanges extending inward from sides, top and bottom of each of a plurality of slots in the web between stud parallel primary flanges.  
         [0035]      FIG. 6  is a rear perspective cut-away view of a metal stud of  FIG. 5 .  
         [0036]      FIG. 7  is a top planar view of the metal stud of  FIG. 5 .  
         [0037]      FIG. 8  is a front perspective view of a metal stud with a slotted web having supplemental flanges extending outward from sides each of a plurality of slots in the web.  
         [0038]      FIG. 9  is a rear perspective view of a metal stud of  FIG. 8 .  
         [0039]      FIG. 10  is a top planar view of the metal stud of  FIG. 8 .  
         [0040]      FIG. 11  is a front perspective view of a metal stud with a slotted web having supplemental flanges extending inward from sides and outward from top and bottom of each of a plurality of slots in the web.  
         [0041]      FIG. 12  is a rear perspective view of a metal stud of  FIG. 11 .  
         [0042]      FIG. 13  is a top planar view of the metal stud of  FIG. 11 .  
         [0043]      FIG. 14  is a rear perspective view of a metal stud with a web with a plurality of slots aligned vertically in the web, each having a single supplemental flange extending inward from the web between stud parallel primary flanges, the supplemental flanges alternating between first and second slot sides for successive adjacent slots.  
         [0044]      FIG. 15  is a rear perspective view of a metal stud with a slotted web having supplemental flanges extending inward from primary flanges.  
         [0045]      FIG. 16  is a front perspective view of a metal stud of  FIG. 15 .  
         [0046]      FIG. 17  is a top planar view of the metal stud of  FIG. 15 .  
         [0047]      FIG. 18  is a rear cut-way perspective view of the slotted stud of  FIG. 4E  shown with insulation filling the stud and passing through the slot and passing beyond the stud as between studs in a wall.  
         [0048]      FIG. 19  is a front perspective view of the stud with insulation of  FIG. 18 .  
         [0049]      FIG. 20  is a front perspective view of a metal stud with a slotted web having supplemental flanges extending inward from the web, the slot further having triangular ends with additional supplemental flanges extending from the triangle sides of those ends.  
         [0050]      FIG. 21  is a rear perspective view of a metal stud of  FIG. 20 .  
         [0051]      FIG. 22  is a top planar view of the metal stud of  FIG. 20 .  
         [0052]      FIG. 23  is a front perspective view of a metal stud with a slotted web having supplemental flanges extending inward from the web, the slot further having semicircular ends with additional supplemental flanges extending from the those semicircular ends.  
         [0053]      FIG. 24  is a rear perspective view of a metal stud of  FIG. 23 .  
         [0054]      FIG. 25  is a top planar view of the metal stud of  FIG. 23 .  
         [0055]      FIG. 26  is a top planar view of a stud with supplemental flanges extending inward from the web and then bending back toward the web.  
         [0056]      FIG. 27  is a rear perspective view of a metal stud showing a plurality of slots each with a supplemental flange continuous around the perimeter of each slot, the slots arrayed in two columns longitudinal in the web with a slot of one column adjacent a slot of the other columns.  
         [0057]      FIG. 28  is a rear perspective view of the stud of  FIG. 27 .  
         [0058]      FIG. 29  is a cross sectional side view of a slot with supplemental flange showing a clip channel over supplemental flange distal ends and secured thereto by a screw passing through a clip plate bridging the slot, the screw threaded into a hole in the clip channel.  
         [0059]      FIG. 30  is a front perspective view of a metal stud showing an array of holes punched through a web forming projections from the web around the holes.  
         [0060]      FIG. 31  is a cross-section view of the metal stud of  FIG. 30  through the view line  31  shown in  FIG. 30 .  
         [0061]      FIG. 32  an enlarged side view a section of the slots of  FIG. 31 .  
         [0062]      FIG. 33  is a perspective view of a metal stud shown with an array of slots, each slot having a supplemental flange continuous around the slot perimeter, the slots arranged in a plurality of columns longitudinal with the stud with slots of one column staggered from slots of an adjacent slot. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0063]     The slotted metal stud  10  of the present invention is intended for use in conventional construction of stud walls. In the conventional manner of wall and building construction, a plurality of studs are spaced apart vertically in parallel between horizontal floor joists and ceiling joists  100 . Typically, a channel stud header  102  connected to the ceiling joists  100  and opening downward receives upper ends  11  of the studs  10 . Similarly, a channel stud footer  104  connected to the floor joists  100  and opening upward receives lower stud ends  13 . Because the joists  100  are required to support a lateral, or transverse load, they are larger and stronger than the studs  10 , which support a compressive, or longitudinal load. The longitudinal loading of a stud  10  with its unique vertical force distribution different from a joist  100  enables design variations consistent with that vertical loading, which design variations are not preferred for joists with joist lateral force distribution. The following therefore pertains uniquely to studs intended for vertical loading.  
         [0064]     The stud  10  comprises a conventional C-shaped channel  12  including a pair of parallel primary flanges  14  extending a same extent orthogonally from and separated by a web  16 . In the preferred embodiment, at least one and preferably a plurality of slots  18  are stamped in the web  16  such that at least one and preferably two supplemental flanges  20  bend out of the slot  18  from first and second slot sides  22 ,  23  bounding the slot  18  to extend inward, between and parallel to the primary flanges  14 . In this manner, the supplemental flanges  14  comprise a substantial areal portion, and typically a third, of the web  16  bending from the web to form the slot. The slots  18  may be arrayed in one or more columns  19 . Two or more columns  19  may be configured with slots  18  side by side in adjacent slot columns as in  FIGS. 27, 28 , and  33  or with slots  18 ′ of one column  19 ′ staggered between or overlapping slots  18 ′ of an adjacent column  19 ″.  
         [0065]     Preferably, the supplemental flanges  20  are similar, symmetrically extending inward from the web  16  from said slot sides  22 ,  24 . Thus, each supplemental flange  20  will be in length between its proximal end at the web to its distal end a distance equal to half of the width of the slot  18 . (In a minor variation, the web  16  is stamped to form a slot  18  with a single supplemental flange  20 ′ that bends inward from a slot side  22 ,  24 , in which case the length of the supplemental flange  20 ′ is the width of the slot  18 .) Though the supplemental flange preferably extends orthogonally from the web, it can also extend from the web at any angle other than perpendicular to the web, as shown in  FIG. 26 .  
         [0066]     Typically, the supplemental flanges  20  comprise a major portion, and even most of the web  16  bending inward between the primary flanges  14  forming the slot  18  and the supplemental flanges  20  therein substantially moving the stud cross sectional center of gravity away from the web  16  therein substantially transferring load support from the web  16  to the primary flanges  14 . In the preferred embodiment, a supplemental flange  20  extends from each side  22 ,  24  of a plurality of slots  18  aligned vertically in the web  16  maintaining symmetry in the stud  10  for uniform load support through the stud. In an alternative embodiment, a first supplemental flange  20 ′ extends from the web  16  at a first slot side  22  of a first slot  18   a , a second supplemental flange  21 ′ extends inward from the web  16  at a second slot side  24  of a second slot  18   b , the second slot  18   b  being adjacent said first slot  18   a , a third supplemental flange  20 ″ extends from the web at the first slot side  22  of a third slot  18   c , the third slot  18   c  being adjacent the second slot  18   b , and a fourth supplemental flange  21 ″ extends inward from the web  16  at the second slot side  22  of a fourth slot  18   d  adjacent the third slot  18   c , the fourth slot  18   d  being adjacent the third slot  18   c  such that the supplemental flanges  20 ′,  21 ′,  20 ″,  21 ″ for successive adjacent slots alternate between extension from first and second slot sides  22 ,  24 . The alternating pattern continues through the web  16  such that there are the same number of supplemental flanges  20 ,  21  on each of the slots&#39; first and second sides  22 ,  24 . Thus configured, the supplemental flanges  20 , which are all similar and all between the primary flanges  14 , extend further away from the web  16 , therein further moving the stud cross sectional center of gravity away from the web  16  more effectively transferring load support from the web  16  to the primary flanges  14 .  
         [0067]     In an further embodiment, the web  16  is stamped to form the described flanges  20  extending from slot sides  22 ,  24  and also to form flanges  20  bending from the slot top  26  and bottom  28  forming four supplemental flanges  30  bending from the slot perimeter extending therefrom either inward to or outward from the  
         [0068]     Although the preferred embodiment is for the supplemental flanges  20  to extend inward such that the stud center of gravity is moved inward the stud and away from the web  16 , thereby transferring more of the stud support from the web  16  and onto the primary flanges  14 , the supplemental flanges  20  may also bend outward, away from the stud  10 . As discussed, there is a structural advantage to moving the center of gravity inward in that the load on the stud is better distributed to the flanges instead of mostly on the web. Similarly, there is also a structural advantage in having the supplementary flanges  20  outward from the web. As given above the primary component in the stud moment of inertia of primary consequence is the term, I=b h 3 /12 where b is the stud base (web dimensional direction), and h is the height (flange directional direction). It is seen that increasing the height even a small amount dramatically increases the stud strength. Thus for a stud beginning with a 2-inch flange and increasing it by 2 inches by extending a supplemental flange outward from the web, the stud strength increases by a factor of 4 3 /2 3 , or 64/8=8. It may also be advantageous for some supplemental flanges to bend inward and some outward.  
         [0069]     In the preferred embodiments, the slot is a rectangular and supplemental flanges  20  extend from the slot  18  either vertically, parallel with the primary flanges, or horizontal, orthogonally to the primary flanges  14 . However, other variations in slot shape are deemed included in the invention. For example, the slot ends (top and/or bottom) may be of triangular shape each with two supplemental flanges bent and extending from the legs of the triangle as shown in  FIG. 20-22 . Similarly, the slot top and/or bottom may be curvilinear, such as shown in  FIG. 23-25  as a semicircle, with a plurality of relatively small supplemental flanges extending from the slot ends. Alternatively, the slot may be punched out its center to produce a continuous and uninterrupted supplemental flange around an oval slot as shown in  FIG. 4E . In a further embodiment, the stud  10  may comprise one or more slots  18  in one or both primary flanges  14  with one or more supplemental flanges  20  extending into the stud  10  as shown in  FIG. 17-19 . The illustration shows a single supplemental flange  20  extending from a slot top  32  , representative of the various alternative configurations of flanges extending from slot top, bottom or sides or a combination of the slot top, bottom or sides as described above for web based supplemental flanges, all of which are deemed included in this invention.  
         [0070]     With the supplemental flanges  20  formed out of the web  16  from web material removed and folded from the web  14  to form the slots  18 , the amount of stud material remains unchanged from a traditional metal stud. Thus, the dimensions of the supplemental flanges in the various configurations described above are defined by the dimensions of the slot from which it bends. That is, two supplemental flanges extending from the two slot sides may each be half the width of the slot. If there are flanges extending from respective ends of a rectangular slot, the side supplemental flanges are reduced in length equal to the sum of the extent of the top and bottom supplemental flanges. In maintaining the same amount of material in the stud, the stud does not reduce in support strength but in fact increases in support strength as calculated above.  
         [0071]     In a still further embodiment shown in  FIG. 30-32 , the slots  18  comprise a plurality of holes punched through the primary flanges  14  or the web  16 , or both, resulting in an array of quasi-conical holes  40  extruding from said primary flanges  14  or web  16 . The figures show the supplemental flanges  14  punched outward for illustrative purposes; however, it should be understood that supplemental flanges punched inward are deemed included in the embodiments of the invention. For these purposes, the term quasi-conical hole means a hole with material from said flanges or web extruded from said flange or web about the hole as characteristically results when a hole is punched through a metal sheet, with a concave curvilinear circumferential side  42  narrowing from a base  44  at the flange or web to the hole perimeter  46  separated from that flange or web by its side  42  giving an appearance of a symmetrical volcano shape.  
         [0072]     The stud  10  may be further strengthened by connecting supplemental flanges with a clip  50  to effect a mechanical load transference across a slot  18 , as shown in  FIG. 29 . Typically, a U-shaped clip channel  52  fits over distal ends  54  of two supplemental flanges  14  extending from opposite slot sides. As shown, a clip plate  56  across the slot  18  is tightened to the clip channel  52  by a threaded screw  58  threaded into a hole  60  in the clip channel  52 . The clip advantageously is of material with minimal thermally and acoustically conductivity.  
         [0073]     Several figures have been provided as illustrative of various embodiments of the invention. The figures are for illustrative purposes only and not as limitations of the invention. A feature illustrated on one figure can be implemented in another configuration or in combination with another configuration. For example, an array of circular slots are deemed to include all possible shapes of slots in an array configuration and not limited to circular slots. Similarly, a figure may show a slot shape with a supplemental flange extending inward from the web or a primary flange and another slot shape or supplemental flange in the same or an alternative configuration extending outward from the web. It should be understood that any slot or supplemental flange shape may be configured to extend inward or outward or in any configuration represented as a feature in another figure by another shape.