Patent ID: 8479661

Claim:
A center sill assembly for a rail road freight car, said center sill assembly comprising: a first portion and a second portion; said first portion including a draft arm in which to mount draft gear and a coupler; said first portion having a top flange, a bottom flange, a first side web and a second side web, said top flange, bottom flange, and first and second side webs co-operating to define a substantially rectangular tube; said draft arm having a first end and a second end, said second end of said draft arm having a striker plate thereat, said first end of said draft arm having an internal peripheral boss formed thereat, and said draft arm having a center plate mounted to said bottom flange thereof closer to said first end than to said second end, said internal peripheral boss extending lengthwise proud of said bottom flange at said first end of said draft arm; said bottom flange of said draft arm having a continuous full width portion between said center plate and said first end, said full width portion having an extent W 2 ; said second portion of said center sill assembly including a top flange, a bottom flange, a first side web and a second side web, said top flange said bottom flange, and said first and second side webs co-operating to define a substantially rectangular tube, said bottom flange including a main portion and a transition portion, said transition portion lying between said main portion and said bottom flange of said draft arm; on assembly, said boss of said draft arm fitting within said substantially rectangular tube of said second portion of said center sill assembly, and said substantially rectangular tube of said second portion of said center sill assembly mating in abutting engagement with said first end of said draft arm; said main portion having an overall flange width W 1 , W 2 being greater than W 1 ; said transition portion having a first end mating with said main portion, and a second end mating with said first end of said bottom flange of said draft arm, said transition portion widening from said main portion toward said draft arm; said main portion of said bottom flange of said second portion of said center sill assembly, said transition portion of said bottom flange of said second portion of said center sill assembly, and said bottom flange of said first portion of said center sill assembly all being substantially co-planar, whereby an in-plane stress path is provided between said bottom flanges of said first and second portions of said center sill assembly.