| 摘要 |
A concrete railway sleeper is moulded by casting, to incorporate a transversely extending lining tube (19) at each end, for containing anchor pins for spring clips which secure the rail to the sleeper. A recess (24%) is moulded into the concrete, around the tube (19) ends, by a grommet (25) of resiliently deformable (rubber) material having a shank (26) which is received within the tube end, and a head (28) which protrudes from the tube end to define the recess and is resiliently deformable into sealing engagement with the tapered wall (38) of the sleeper casting mould. The grommet (25) and tube (19) are retained in the mould during moulding, by a positioning rod (36) which passes through the bore (27) of a steel grommet lens (34). The grommet (25) bears on the mould wall, at a steel caster (33), and the grommet shank (26) is externally tapered, and has axially extending ribs which locate against the tube (19). <IMAGE> |
