| 摘要 |
A fishplate comprises two portions 18 and 19 which are set at 120 DEG to each other. The fishplate has two edge portions 21,22 which are bulbous shaped and are joined by flat portion 23 in which there are rectangular apertures 24 for bolts to pass through. At the inner edge of the fishpate is a curved indentation 25 which is adapted to accommodate the junction of the RSJs forming the colliery support. Without this indentation, if the inner edge followed the line 26 the portion marked 27 would foul the RSJ beams. The curved portion is formed in the bulbous inner edge 22. The symmetry of the fishplate enables it to be used in either the right hand or left hand position and it is so shaped that is will fit snugly into the flanges of the RSJs. |
