Patents
Patents for E01B 3 - Transverse or longitudinal sleepers; Other means resting directly on the ballastway for supporting rails (1,703)
11/1976
11/30/1976US3994436 Composite railway tie
04/1976
04/06/1976US3948010 Reinforcing device for an element of prestressed concrete
03/1976
03/16/1976US3943818 Railroad tie
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