| 摘要 |
A revolving frame (21) for a work machine is provided which has a welded structure capable of reducing the influence of the stresses from a centre frame (23) on a portion, in which a beam (26) is welded to the center frame, and also capable of securing the load supporting strength of the beam. A skirt beam (26) welded further toward a rear side than a center of an entire length in a longitudinal direction of a center frame (23A) has a pair of beam side plates (42) welded to a region on a lower side than the center in a height direction of a side surface (24a) of the center frame (23A) by a vertical welding portion (41). Upper portions of distal end portions of the beam side plates (42) near the side surface (24a) are notched to form a pair of notch grooves (43). A beam upper plate (44) is welded between and integrated with the upper portions of these beam side plates (42). A notch connection plate (45) is welded between the pair of beam side plates (42) so as to extend from the beam upper plate (44) to reach the side surface (24a) along the notch grooves (43), and a distal end of the notch connection plate (45) is welded to an intermediate portion in the height direction of the side surface (24a) by a horizontal welding portion (46). |
