Concrete railway sleeper fixing screw - fits into plastics socket with threads cast into sleeper during manufacture (NL 23.5.77)

摘要

Device for mixing screws in cast concrete elements is esp suitable for screwing into railway track concrete sleepers. It involves screw-accommodating media integrated into the concrete element when it is being formed. These comprise a socket (I) for insertion into the form providing a widening seating for accommodation of two half shells (2a, 2b). These are shaped on the inside so as to make a screw-in opening (3). On the outside they at least partially fit the widening seating shape, so as to furnish an anchoring wedge for the screw. The socket and half shells may be made of plastics and the socket may also be made up from two parts, plugged together.