| 主权项 |
1. A method of manufacturing a side frame of a rail car, where the side frame includes a pair of pedestals for mounting wheel sets, the method comprising:
packing a first molding material around a first side frame pattern in a first flask and subsequently removing the first side frame pattern from the first molding material to thereby form a drag portion of a mold, wherein the drag portion of the mold defines at least a portion of a pair of pedestal jaws each including at least a portion of a pedestal roof, an outboard vertical jaw, an inboard vertical jaw, an inboard thrust lug, and an outboard thrust lug, wherein the first molding material is a chemical or resin binder material; packing a second molding material around a second side frame pattern in a second flask and subsequently removing the second side frame pattern from the second molding material to thereby form a cope portion of the mold, wherein the cope portion of the mold defines at least a portion of a pair of pedestal jaws each including at least a portion of a pedestal roof, an outboard vertical jaw, an inboard vertical jaw, an inboard thrust lug, and an outboard thrust lug, wherein the second molding material is a chemical or resin binder material; forming a plurality of risers in the mold; inserting a plurality of cores that define an interior region of a cast side frame into the drag portion of the mold; closing the mold; pouring a molten material into the mold through at least one feed path to form a side frame casting, wherein the at least one feed path is positioned in a center region of the mold and is at least partially formed by the first pattern; removing the side frame casting from the mold, wherein the side frame casting includes a pair of side frame columns and each side frame column includes at least one column stiffener positioned on an inner surface of a side frame column, extending between drag and cope portions of the side frame, and defining a bolt hole opening; removing rigging from the side frame casting; finishing the side frame casting; wherein a surface finish of the side frame casting is less than 750 micro-inches RMS; wherein a pedestal surface finish is less than 500 micro-inches RMS; wherein a thrust lug draft angle of the side frame casting is no more than about ¾ degree; wherein a pedestal roof draft angle of the side frame casting is no more than about ¾ degree; wherein a jaw draft angle of the side frame casting is no more than about ¾ degree; wherein each side frame column includes at least two side frame stiffeners, and wherein a margin of error in a spacing between respective bolt hole openings of each side frame column are within about +/−0.020 inches; wherein the thickness of each side frame column in the region of the column stiffeners is about 1.125 inches; wherein the plurality of cores comprise a pair of pedestal cores, a bolster opening core, a spring seat core, a lower tension member core, and a pair of inner jaw cores; wherein the bolster opening core defines a pair of lightener openings; and wherein each of the lightener openings are centered about 10.6 inches above a spring seat and about 2 inches inboard from the nearest side frame column. |
