Terex HPR4519 and HPR5123 Hydraulic Rock Drill Service Manual (416421)

The Terex HPR4519 and HPR5123 Hydraulic Rock Drills are percussion-style drilling systems used in mining and construction environments. This Service Manual explores percussion assembly behavior, lubrication paths, rotation control, hydraulic pressure regulation, and feed system coordination. It’s tailored for technicians diagnosing torque loss, weak impact force, overheating percussion modules, or irregular penetration speed.

Applications & Use Cases

• Servicing percussion pistons, liners, and wear components

• Diagnosing rotary drive instability

• Adjusting hydraulic pressure for drilling consistency

• Inspecting feed cylinder alignment and lubrication flow

• Rebuilding rock drill modules after heavy use

FAQ
Does the manual provide percussion system specs?
Yes, including impact output parameters.

Is it suitable for deep drilling service routines?
Yes. It covers common failure modes and wear areas.

Safety Note
Isolate hydraulic power and release feed pressure before accessing percussion components.

The Terex HPR4519 and HPR5123 Hydraulic Rock Drills are high-performance, percussion-style drilling units used on drill rigs in mining, quarrying, and heavy construction. They are designed for hole drilling in hard rock formations where consistent penetration and tool life are critical. This service manual (416421) provides detailed procedures for disassembly, inspection, and reassembly of the rock drill assemblies. It also covers hydraulic system interfaces, wear component replacement, and troubleshooting guidance for field and shop technicians.

Applications & Use Cases

• Production blasthole drilling in open-pit and underground mining operations.
• Bench drilling and controlled blasting in quarry applications.
• Rock support drilling for anchors, bolts, and dowels in tunneling projects.
• Foundation and tie-back drilling on civil construction sites with hard rock conditions.
• Maintenance planning and overhaul scheduling for fleet-managed drilling equipment.

FAQ

Q: Can this manual be used to set up the hydraulic rock drill on a different carrier?

A: Yes, for compatible carriers; use the hydraulic connection and mounting information to verify flows, pressures, and mechanical fit before installation.

Q: Does the manual include troubleshooting for loss of impact energy?

A: Yes, it outlines checks for hydraulic supply, accumulator charge, internal leakage, and wear of impact and rotation components.

Safety Note

Always depressurize hydraulic circuits and secure the rock drill before any service or disassembly work.

Terex HPR4519 and HPR5123 Hydraulic Rock Drill Index:

• Parts Ordering & Product Support
• Introduction
• Table of Contents
• Safety – Section 1
  • Overview of Potential Hazards
  • Safety Instructions
    • Before Operation
    • Operation
    • Maintenance
• General Maintenance – Section 2
  • Operation & Maintenance
    • Start-Up Procedure
    • Operating Tips
    • General Maintenance Tips
      • Accumulator Pressures
      • Contamination
      • Major Repairs
  • Preventive Maintenance
    • At the beginning of every shift
    • Every Two Hours
    • Every 500 Hours or 3 Months
• Troubleshooting – Section 3
  • Troubleshooting Chart
• Drill Disassembly & Inspection – Section 4
  • General Tips on Drill Overhaul
  • Tools Required
  • Special Tools
    • Special Tool List for HPR4519 Drill (Optional)
    • Special Tool List for HPR5123 Drill (Optional)
  • HPR4519/5123 Exploded View
  • HPR4519/5123 Parts List
  • Drill Disassembly
    • General Information
    • Water Swivel Assembly – Removal
    • Water Swivel Housing – Repair
    • Chuck End Cover – Removal
    • Chuck Driver & Pinion Gear – Removal & Inspection
    • Rotation Housing – Internal Parts
    • Rotation Motor – Removal
    • Rotation Housing – Removal from Cylinder
    • Drill Cylinder Components
    • Cylinder – Internal Parts
    • Backhead – Removal and Inspection
    • Hammer and Bushings – Removal and Inspection
    • Shuttle Valve – Internal Parts
    • Shuttle Valve – Removal and Inspection
    • Accumulator – Internal Parts
    • Accumulators – Removal
    • Accumulators – Disassembly and Inspection
• Drill Assembly – Section 5
  • General Tips on Drill Overhaul
  • Capscrew Torque Specifications
  • HPR4519/5123 Exploded View
  • HPR4519/5123 Parts List
  • Drill Assembly
    • Cylinder – Internal Parts
    • Rear Cylinder Bushing and Backhead – Installation
    • Hammer – Installation
    • Cylinder – Internal Parts
    • Front Cylinder Bushing – Installation
    • Accumulator – Internal Parts
    • Accumulators – Assembly and Installation
    • Shuttle Valve – Internal Parts
    • Shuttle Valve – Assembly
    • Shuttle Valve – Installation
    • Rotation Housing – Internal Parts
    • Rotation Housing – Assembly
    • Chuck Driver – Assembly
    • Shank Installation
    • Water Swivel – Assembly
• Charging the Accumulators – Section 6
  • Requirements
  • Procedure
  • Checking the Accumulator Charge Pressure
  • Accumulator Charge Kit
• Specifications – Section 7
  • Hydraulic Oils for Percussion Drills
  • Hydraulic Drill Rotation Unit Lubrication
    • Grease Lubrication with a Hand Grease Gun
    • Frequency
    • Grease Specifications
  • HPR4519 Wear Tolerances
  • HPR5123 Wear Tolerances
  • MAINTENANCE RECORD
• Index

Terex