Railroad tie with accurately located and centered embedded anchor inserts

Abstract From the Canadian patent

The present invention provides a process for precasting workpieces of prestressed concrete containing prefabricated internally threaded screw anchors comprising the, steps of: (a) providing a form of a shape corresponding to that of at least one workpiece with a horizontal nut fixedly secured to the bottom of said form; (b) securing reinforcing armatures under tension to said form above said bottom; (c) removably attaching a prefabricated screw anchor to said form by threading a headed bolt from above through the screw anchor into engagement with said nut, said bolt passing with clearance through the screw anchor without engaging the internal thread thereof; (d) pouring concrete into the …