| 摘要 |
A roll-formed grid runner comprising a sheet metal strip folded into an upper hollow single wall reinforcing bulb, a double wall web below the bulb, a channel extending laterally from both sides of a lower end of the web to a bend and upwardly from the bend to a panel supporting elevation, the bend on each side of the web existing at a longitudinally extending score line where a thickness of the strip is locally reduced. |
