Sumitomo SH-120-3 Excavator Overview

[MikePhua]

The Sumitomo SH-120-3 is part of the SH series, a line of excavators from Sumitomo Construction Machinery. Known for its reliability and performance, the SH-120-3 is frequently used in various industries, from construction to mining and landscaping. The model is widely regarded for its robustness and versatility in demanding work environments. In this article, we'll dive into the specifics of the SH-120-3, its features, common issues, and overall performance.
Background and Company Overview
Sumitomo Construction Machinery, part of the Sumitomo Heavy Industries group, has been a significant player in the global construction machinery industry. Established in the 1960s, the company developed a strong reputation for its high-quality excavators and cranes. The SH series excavators, including the SH-120-3, were engineered to provide superior operational performance, durability, and ease of maintenance, making them popular choices for a wide range of projects.
Sumitomo’s SH series excavators, including the SH-120-3, were designed with input from engineers and operators in the field. This allowed Sumitomo to address both the mechanical and operational needs that would best suit a wide variety of applications.
Specifications and Features
The Sumitomo SH-120-3 is a mid-sized, hydraulic crawler excavator known for its efficient operation and strong digging power. Here are some of its key specifications:

• Operating Weight: 12,000 kg (approximately 26,455 lbs)
  
• Engine: Powered by a Komatsu SAA6D102E-2 engine
  • Power Output: Around 85 kW (113 HP)
    
  • Fuel Tank Capacity: 400 liters (106 US gallons)
    
• Digging Depth: Approx. 6,100 mm (20 feet)
  
• Bucket Capacity: Around 0.5-0.6 cubic meters depending on the bucket used
  
• Hydraulic Flow: The SH-120-3 is equipped with a high-flow hydraulic system, offering ample power for a variety of attachments.
  
• Boom Length: 6 meters (19.7 feet)
  
• Arm Length: 2.7 meters (8.9 feet)
  

The SH-120-3 offers a balance between power and fuel efficiency, making it well-suited for both heavy-duty and precision work. Its Komatsu engine, known for its durability and smooth operation, contributes to the machine's overall reliability.
Performance and Applications
The SH-120-3 is highly versatile, with the capability to perform a range of tasks, including digging, lifting, and earthmoving. It is often employed in:

1. Excavation: The SH-120-3 excels in both heavy-duty excavation and fine grading tasks. Its powerful hydraulics enable smooth operation of attachments like buckets, breakers, and augers.
   
2. Construction: From foundation work to demolition, the SH-120-3 provides consistent performance on construction sites, with its robust undercarriage offering stability on various terrains.
   
3. Landscaping: In addition to heavy construction work, the SH-120-3 is commonly used in landscaping tasks, such as trenching for utilities and digging ponds or ditches.
   
4. Mining: The excavator’s powerful engine and hydraulic system make it suitable for mining operations, where it handles the extraction of materials such as coal, sand, or gravel.
   

Its hydraulic efficiency and durability also allow it to be equipped with a range of attachments, enhancing its versatility and making it ideal for various tasks in both urban and rural settings.
Common Issues and Maintenance
Like all construction machinery, the Sumitomo SH-120-3 is subject to wear and tear, especially when used in harsh conditions. Here are some of the most common issues and maintenance considerations for this model:

1. Hydraulic System Leaks
   Hydraulic leaks are common in older excavators, especially if the machine has been used heavily in demanding environments. This could manifest as a loss of hydraulic fluid, causing the machine’s performance to degrade. Regular inspection of hoses, seals, and joints is critical to ensuring the hydraulic system remains in top condition.
   • Solution: Check all hydraulic connections, hoses, and seals for leaks. Replace any worn or damaged components. Regularly top off hydraulic fluid to ensure optimal performance.
     
2. Engine Overheating
   Overheating can occur if the engine is not properly maintained or if the cooling system is blocked or clogged. Dust and debris can accumulate on the radiator, reducing airflow and causing engine temperature to rise.
   • Solution: Ensure that the cooling system is regularly cleaned. Check coolant levels and look for any blockages in the cooling lines. It’s also a good idea to monitor engine performance and temperature readings during operation.
     
3. Track and Undercarriage Wear
   The undercarriage of the SH-120-3 is subject to significant wear due to constant movement on rough terrain. Track tension, sprocket condition, and track link wear can all contribute to a decrease in performance and fuel efficiency.
   • Solution: Inspect the undercarriage frequently. Replace worn track links, sprockets, and rollers as needed. Properly tension the tracks to reduce wear and prevent costly repairs.
     
4. Electrical and Sensor Issues
   Over time, the excavator's electrical system may develop faults, including issues with sensors or wiring. This can lead to the failure of crucial systems, including the engine control unit (ECU) or the hydraulic controls.
   • Solution: Regularly check the electrical wiring and replace any faulty sensors. Use diagnostic tools to identify and fix any electrical faults before they lead to major breakdowns.
     
5. Cabin Comfort and Ergonomics
   Operators may experience discomfort during long shifts, particularly if the cabin is not properly maintained. Issues such as air conditioning failure, seat wear, and poor visibility can negatively impact productivity.
   • Solution: Regularly clean the cabin, check the air conditioning system, and replace worn seats. Upgrading to ergonomic seating and ensuring proper visibility can greatly improve operator comfort.
     

Tips for Maintaining Your SH-120-3

1. Scheduled Maintenance
   Like all heavy machinery, following the manufacturer’s recommended maintenance schedule is essential. This includes checking fluid levels, changing filters, inspecting hydraulic lines, and replacing worn parts on a regular basis. Preventative maintenance helps extend the machine’s lifespan and reduce unexpected downtime.
   
2. Operator Training
   Proper operator training can prevent unnecessary strain on the machine. Teach operators to monitor gauges, avoid overloading, and maintain proper speeds and hydraulic pressures to optimize the machine’s performance.
   
3. Use OEM Parts
   When replacing parts, always use original equipment manufacturer (OEM) parts. These parts are specifically designed for your SH-120-3 and will ensure the best performance and durability.
   
4. Storage
   When the excavator is not in use for extended periods, store it in a dry, covered area to prevent rust and deterioration. Additionally, it’s important to drain any water from the fuel tank and change any fluids that could degrade over time.
   

Conclusion
The Sumitomo SH-120-3 excavator is a reliable and versatile machine capable of handling a variety of tasks in construction, landscaping, and even mining. With its powerful engine, robust hydraulics, and reliable performance, the SH-120-3 is a staple in the heavy equipment industry. However, as with any piece of heavy machinery, regular maintenance and timely repairs are essential to ensure long-term performance and minimize downtime.
For those considering the SH-120-3 for their operations, it's crucial to keep an eye on common issues such as hydraulic leaks, engine overheating, and undercarriage wear. By following proper maintenance practices and using OEM parts, operators can maximize the machine's efficiency and lifespan, keeping their projects on track and within budget.