The utility model discloses a 3MM stone returns fluid welding tray, including disk body and longitudinal baffle, the disk body internal fixation is equipped with a plurality of horizontal separators,horizontal separators's top is equipped with a plurality of first recesses, the bottom of longitudinal baffle is equipped with a plurality of second recesses, horizontal separators and longitudinal baffle accessible recess block are connected, the fore -and -aft both ends of disk body all are equipped with the magnetic stripe groove, magnetic stripe inslot block is connected with the magnetic stripe, horizontal separators's bottom is fixed and is equipped with a plurality of spring assembly, spring assembly includes spring and magnetic path, the one end and the horizontal separators fixed connection of spring, the other end of spring and the one end fixed connection of magnetic path. The utility model discloses an utilize magnetism to fix PCB, it is both convenient effective, also reducedthe condition that time fluid welding in -process PCB warp, but the longitudinal baffle through setting up a plurality of first recesses and block can make the box body be applicable to the PCB of multiple width, through setting up spring assembly for the box body is applicable in the PCB of various thickness.