| 摘要 |
A beam for a grid in a ceiling that has drywall affixed to the grid by self-tapping screws. The beam has a hem rolled downwardly and inwardly along the edge of both flanges of the beam. The hem prevents the flange from bending upward and sliding off the screw tip. The screw tip enters one of many indentations in the flange and is captured. The captured screw tip penetrates the flange and secures the drywall to the beam. The beam does not have a face cap over the flanges.
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