Hitachi-9068144-EX100 Forged Front Idler Wheel Group-Heavy-Duty Undercarriage Component

Product Specifications

The Hitachi EX100 Forged Front Idler Wheel Group is a critical undercarriage assembly designed for Hitachi EX100-series hydraulic excavators. As the track system's forward guide mechanism, it performs three essential functions:

1. Track Alignment – Maintains proper chain travel path

2. Tension Regulation – Works with adjuster to optimize track tightness

3. Load Distribution – Transfers machine weight to lower track rollers

2. Manufacturing & Material Specifications

Core Construction

• Forging Process:

  • Hot-forged from 34CrNiMo6 alloy steel (EN 10083-3 standard)

  • Grain flow optimized for directional strength

• Machining Tolerance:

  • ±0.1mm on bore diameter (ISO 286-2 H7 tolerance)

  • Runout <0.05mm on flange surfaces

Hardening Treatment

3. Bearing & Seal System

Bearing Assembly

• Type: Double-row tapered roller bearing (ISO 355:2017)

• Brand Options: SKF 32222J2/Q or NTN 4T-32222

• Preload: 0.05-0.08mm axial clearance (adjusted via shims)

Sealing Technology

• Primary Seal: Triple-lip nitrile rubber (DIN 3760 A1B1)

• Secondary Defense:

  • Labyrinth dust exclusion channels

  • Grease purge port (Zerk fitting)

4. Dimensional Data

5. Performance Characteristics

Durability Metrics

• Fatigue Life: >500,000 cycles (ISO 15653 simulated loading)

• Abrasion Resistance: <0.15mm wear/100hrs in silica sand (ASTM G65)

• Static Load Capacity: 78kN radial / 32kN axial

Environmental Ratings

• Temperature Range: -30°C to +120°C (seals rated to +150°C peak)

• IP Protection: IP69K (high-pressure wash resistant)

6. Compatibility & Interchangeability

Direct-Fit Models

• Hitachi EX100-1 ~ EX100-5

• Hitachi ZX100-3 ~ ZX100-5G

• Replaces OEM P/N: 9092973

Aftermarket Cross-References

• DPW: TRK-100F-ID

• CQC: UND-EX100-FI

• Komatsu: Not recommended (flange profile mismatch)

7. Maintenance Protocol

Installation Procedure

1. Clean track frame mating surfaces with acetone

2. Apply Molykote G-Rapid Plus to bolt threads

3. Torque sequence:

   • Stage 1: 300 N·m

   • Stage 2: +90° rotation

4. Final track tension: 35mm sag at 3.5kgf measurement

Service Intervals

• Greasing: Every 500hrs (Shell Gadus S2 V220 2)

• Bearing Inspection: Ultrasonic testing every 2,000hrs

8. Failure Analysis Guide

9. Procurement Options

Global Supply Channels

Packaging Details

• Export Crating:

  • Wooden box with desiccant (800x600x400mm)

  • Gross weight: 72kg

  • 1 unit per crate

10. Technical Compliance

• Certifications:

  • CE Marking (EU Machinery Directive)

  • GOST-R (CU-TR Certification)

  • MSHA Approval (US Mining)