CONSTRUCTION MACHINE, TRUCK FRAME OF CONSTRUCTION MACHINE AND MANUFACTURING METHOD OF TRUCK FRAME

摘要

PROBLEM TO BE SOLVED: To provide a construction machine capable of reducing stress concentration without deteriorating the strength of a round body itself. SOLUTION: A recessed curved part 5 composing of a first curved part 5a, a second curved part 5b continuing to the first curved part 5a, and a third curved part 5c continuing to the second curved part 5b, is formed on the outer peripheral surface of the round body 4c having a lower part fixed to a center frame 4a of a truck frame 4 provided on the construction machine. Since the radius of the recessed curved part 5 can be large, the stress concentrated to the welded part of the round body 4c and the center frame 4a can be reduced, and it can be prevented that crack is generated on the welded part by an excessive concentration stress or the round body 4c is broken from the welded part. COPYRIGHT: (C)2005,JPO&NCIPI