PURPOSE: To obtain a lightweight tray device for heat treatment of shafts in a perpendicular state by vertically and laterally connecting the respective tubular sleeves of upper and lower decks with ribs and disposing large clearances through which fluid is passable, thereby forming an integral structure.

CONSTITUTION: The many tubular sleeves 8 having supporting apertures 7 for inserting and supporting the bottom ends of the shafts, etc., are connected by horizontal ribs 9 and are enclosed by enclosure ribs 9a, to form the upper deck 5. Similarly, the lower deck 6 is composed of the tubular sleeves 12 having the supporting apertures 11, the horizontal ribs 13 and the enclosure ribs 13a. The upper and lower decks 5, 6 are connected by perpendicular struts 14 and the large clearances 15 are formed therebetween, to obtain an assembly 4 to ensure the smoothing of fluid flow. The assembly 4 is preferably formed to one piece by casting. As a result, the integral structure tray device, which is capable of heat treating the shaft 1 consisting of shafts 2, gears 3, etc., by automatically loading the shafts, is light in weight and has the sufficient strength to withstand transportation is obtd.