| 摘要 |
The grating comprises longitudinal (1) and transverse (2) bars. The latter are indented to accommodate the longitudinal ones where they cross, the longitudinal ones fitting partly inside the indentations. At these positions, the bars are permanently secured together by set-screws (12, 13), which pass through bores (11) in the longitudinal members and engage in blind tapped holes (21) in the transverse bars. The set-screws can be Allen-headed, steel balls (13) being hammered into the heads. The longitudinal bars can be counterbored (11a) to accommodate the heads. |
