3037079 Original Excavator Parts Bucket Shaft Pin Shaft for EX100 EX100-2 EX120 EX120-2

The part number 3037079 is marked as PIN Link to Dipper in Hitachi's original part number system, which refers to the main load-bearing pin in the bucket linkage mechanism where the H-Link (I-frame/linkage assembly) is hinged and fixed to the end ear seat of the Dipper Arm. It is not a bucket pin between the bucket and H-Link (which is 3037080/3037081), but a connecting rod stick hinge pin closer to the root of the stick, directly bearing excavation reaction force and impact bending moment. This item is mainly suitable for EX series 20 ton platforms: EX100、EX100-1/2/3/5、EX100M、EX100W/EX100WD、EX120、EX120-1/2/3/5、EX120K  Wait for the bucket linkage of the model.

As the core load-bearing pin of the front-end working device, its main function is to establish a rotatable hinge point between the ear seat at the end of the bucket and the connecting rod/H-Link, transmitting the huge reaction force of the bucket excavation to the main structure of the bucket in the form of shear and bending. At the same time, the lubrication channel (oil hole/oil groove) ensures that there is still an oil film to reduce friction under heavy load swing. Original factory sales shafts are usually made of high-quality carbon or alloy steel (such as 45 # quenched and tempered or 40Cr), which undergoes turning → milling oil grooves/drilling oil holes → heat treatment (surface induction hardening or overall quenching and tempering, with surface hardness often controlled at HRC 50-58 level and core toughness maintained) → precision grinding of the outer circle, with standard Snap Ring grooves at both ends or elastic retaining rings for hole positioning.

The majority of its lifespan depends on three things: proper lubrication, the condition of the lining, and the absence of the retaining ring. Every 8-10 working hours (or every shift), the hinge point should be greased with grease through a grease nipple until the old oil is pushed out and the new grease overflows cleanly; If one side can never enter the grease/overflow hole and no oil can be discharged, it indicates that the oil passage is blocked or the liner is rotated incorrectly, and it should be dealt with as soon as possible. Regular inspection (recommended every 500 hours): Check if there is an increase in the axial displacement of the pin shaft on the outer side of the bucket rod ear seat, if the retaining ring is deformed/partially slotted, if there are cracks at the root of the ear seat, and if there is obvious shaking in the middle of the pin by hand - if the shaking is large and the clearance between the bushings exceeds the standard, the pin and bushing should be replaced in pairs, not just half.