Product Overview

The Carrier Roller, also known as Top Roller or Upper Roller, is mounted above the track frame of Hitachi EX100 and EX120 crawler excavators.

Its primary function is to support the upper section of the track chain and maintain correct track alignment during travelling. The carrier roller also helps reduce friction between the track chain and undercarriage frame.

A worn or seized carrier roller may cause:

• Track chain vibration
• Abnormal travelling noise
• Increased travelling resistance
• Uneven track chain movement
• Accelerated track link and bushing wear
• Increased undercarriage maintenance costs

Our EX100 / EX120 carrier rollers are manufactured using professional undercarriage production processes and provide a reliable aftermarket replacement solution for equipment dealers, distributors, repair workshops and fleet operators.

Key Features & Benefits

Wide Model Compatibility

Designed for compatible:

• Hitachi EX100
• Hitachi EX120

The exact fitment should be confirmed according to machine serial number and existing undercarriage configuration.

High-Strength Alloy Steel

Manufactured from:

40Mn2 Alloy Steel

Providing:

• High structural strength
• Good impact resistance
• Strong fatigue resistance
• Excellent wear resistance
• Long service life

Precision Heat Treatment

The roller working surface is subjected to controlled heat treatment.

Typical specification:

• Surface hardness: HRC 52-58
• Hardening depth: 5mm-10mm

This improves resistance to continuous track-chain contact and abrasive working environments.

Reliable Floating Seal System

Equipped with:

• Heavy-duty floating oil seals
• Wear-resistant bushings
• Lifetime internal lubrication

The sealed structure helps retain lubricant and protect internal components against dust, mud and water contamination.

OEM-Style Direct Replacement

Manufactured with controlled:

• Roller diameter
• Shaft dimensions
• Mounting dimensions
• Track-chain contact dimensions

Designed for bolt-on replacement when the correct configuration is selected.

Technical Specifications