Patent ID: 7712515
Filing Date: 2010-05-11
Classification: E02D

Abstract:
1. A method for manufacturing a frame for use in municipal castings, comprising the steps of: defining a mold cavity in a shape of the frame; providing a core having a shape corresponding to a desired shape of a bolt hole and a nut retainer, the core having a bolt hole portion and a nut retainer portion, the nut retainer portion configured to define a void shaped to receive the nut and to prevent rotation of the nut, the void having a mouth through which the nut is inserted into the void, the nut retainer portion configured to define a protrusion extending into the void adjacent the mouth, the protrusion retaining the nut within the void and preventing substantial movement of said nut in the direction away from said bolt hole portion; inserting the core into the mold cavity; introducing frame material into the mold cavity; allowing the frame material to cure into a cast frame; removing the cast frame from the mold cavity; and removing the core from the cast frame, the core leaving a cast bolt hole and a cast nut retainer in the frame.