1. An apparatus for classifying flanged pipes comprising an elongated tray having a plurality of vertical supporting plates arranged with a spacing, a guiding means for said tray having a V-shaped passage, a chain conveyor provided along said passage for conveying said tray, an attachment provided in said chain conveyor for engaging with said tray, rails connected terminal end of said guiding means arranged with a spacing for guiding said tray, stands provided near said rails, brackets provided to slide along said stands and adapted to locate between said rails, tray holders pivotaly mounted on said bracket for holding said tray, means for sliding said bracket along said stands, stages provided along the pass of said tray holders for discharging the pipe on the tray, conveyor provided on each stage, means for engaging said tray holder provided on each stage for inclining said tray holders to discharge the pipe on the tray.