Base carrier for tracklaying vehicle and hard facing method
AssigneeKomatsu Ltd.
InventorMasaharu Amano
Life of this patent
Estimating the term…
Abstract
The objects of the invention are: a weld overlay having stable quality is provided; cracks which have been created on a weld overlay during engagement of a part with its mating member are prevented from extending; and adverse effects on the wear of mating member are avoided. A weld overlay containing hard particles is formed on each tooth of a sprocket 6 such that each bead extending a direction (direction B) perpendicular to the rotating direction of the sprocket 6. A weld overlay containing hard particles is formed on the outer peripheral surface of a bushing such that each bead extends in a direction perpendicular to the rotating direction of the sprocket, the outer peripheral surface serving as a contact surface for the sprocket which engages with the bushing.
Claims29
A base carrier for a tracklaying vehicle, the base carrier comprising a crawler belt having bushings each mounted between a pair opposed links and a sprocket having a plurality of teeth meshing with the bushings respectively,
- each of the sprocket teeth having a weld overlay containing hard particles and composed of beads each running in a direction transverse to the rotating direction of the sprocket,
- the hard particles being contained in the weld overlay so as not to protrude from the surface of the weld overlay and so as to be densely distributed in the bottom area of the weld overlay.
A base carrier for a tracklaying vehicle, the base carrier comprising a crawler belt having bushings each mounted between a pair of opposed links and a sprocket having a plurality of teeth meshing with the bushings respectively,
- wherein a weld overlay containing hard particles is formed on the outer peripheral surface of each of the bushings, the outer peripheral surface serving as a contact surface for the sprocket that engages with the bushing and wherein the core of each bushing is made of steel of high tenacity,
- the hard particles being contained in the weld overlay so as not to protrude from the surface of the weld overlay and so as to be densely distributed in the bottom area of the weld overlay.
A hard facing method for applying a weld overlay to each of the tooth flanks of a sprocket having a plurality of teeth to produce wear-resistant sprocket teeth,
- wherein overlaying is successively carried out such that each bead extends in a direction transverse to the rotating direction of the sprocket teeth and interpass temperature is controlled so as to make the amount of heat input for each tooth substantially constant during the overlaying.
A hard facing method for applying a weld overlay to the outer peripheral surface of a bushing to produce a wear-resistant bushing, the inner and outer peripheral surfaces of the bushing having been subjected to machining, the method comprising:
- a) a weld overlay formation step for supplying hard particles to a molten weld pool being formed on a base material of the bushing by use of an arc to form a weld overlay containing the hard particles on the base material;
- b) a first thermal treatment step for applying gas carburization to the bushing on which the weld overlay has been formed;
- and
- c) a second thermal treatment step for applying reheating/quenching and tempering to the bushing after the first thermal treatment step.
A hard facing method for applying a weld overlay to the outer peripheral surface of a bushing to produce a wear-resistant bushing, the inner and outer peripheral surfaces of the bushing having been subjected to machining, the method comprising:
- (a) a weld overlay formation step for supplying hard particles to a molten weld pool being formed on a base material of the bushing by use of an arc to form a weld overlay containing the hard particles on the base material;
- (b) a first thermal treatment step for applying non-oxidative heating/oil hardening and tempering to the bushing on which the weld overlay has been formed;
- and
- (c) a second thermal treatment step for carrying out, subsequently to the first thermal treatment step, inner-peripheral-surface hardening and tempering, the inner-peripheral-surface hardening being carried out in such a manner that the inner peripheral surface of the bushing is subjected to induction heating while the outer peripheral surface thereof being cooled.
A base carrier for a tracklaying vehicle, the base carrier comprising a crawler belt having bushings each mounted between a pair of opposed links and a sprocket having a plurality of teeth meshing with the bushings respectively,
- each of the sprocket teeth having a weld overlay containing hard particles and composed of beads each running in a direction transverse to the rotating direction of the sprocket,
- wherein a weld overlay containing hard particles is formed on the outer peripheral surface of each of the bushings, the outer peripheral surface serving as a contact surface for the sprocket that engages with the bushing and wherein the core of each bushing is made of steel of high tenacity,
- the hard particles being contained in the weld overlay so as not to protrude from the surface of the weld overlay and so as to be densely distributed in the bottom area of the weld overlay.
Dependencies are inferred from the claim text.