Excavators have evolved into sophisticated machines, leveraging hydraulic power, compact turning radii, and intuitive joystick controls. These powerful and versatile machines are indispensable across industries like construction, utility, public works, mining, demolition, forestry, and landscaping for tasks such as digging trenches, holes, and foundations.
Components of an Excavator:
| Component | Description |
| Cab | The operator’s station, where the machine is controlled via pedals and joysticks. Modern cabs prioritize ergonomics for operator comfort and productivity. |
| House | The main body containing the engine, oil, and fuel cylinders. It’s connected to the undercarriage by a cylindrical casing, allowing for full 360-degree rotation. |
| Engine | Typically a diesel engine, providing the necessary power for both machine movement and the hydraulic system that operates the boom, stick, and attachments. |
| Undercarriage | Comprises the gears and motor responsible for moving the machine over the ground. This includes tracks (for crawler excavators) or wheels (for wheeled excavators). |
| Boom | The primary extension arm that connects to the stick and ultimately holds the bucket or other attachments. |
| Stick | Connects the boom to the bucket or attachment. It extends or retracts to adjust the reach and depth of the digging or lifting operation. |
Choosing the Right Excavator: Key Factors
Selecting the appropriate excavator involves considering size, control systems, and job site requirements.
Size:
Excavator size dictates digging depth and power. The industry categorizes excavators by operating weight:
| Operating Size | Terminology |
| 0 – 6 Metric Tons | Micro, Compact |
| 6 – 25 Metric Tons | Mini, Construction Class |
| 25 – 40 Metric Tons | Mini, Construction Class |
| 40 – 90 Metric Tons | Large, Production Class |
It’s crucial to match the excavator size to your job requirements. Over-specifying can lead to unnecessary costs in purchase price, fuel consumption, and transport.
Controls:
Two primary control patterns exist, established by the Society of Automotive Engineers (SAE) and the International Organization for Standardization (ISO). While similar, the key difference lies in the reversal of controls for the boom arm and dipper (stick) arm. SAE controls are generally preferred in the U.S. Understanding this distinction is vital, especially when buying used equipment, as it impacts operator familiarity and productivity.
- ISO Controls: Left joystick controls swing and stick, right joystick controls boom and bucket.
- SAE Controls: Left joystick controls swing and boom, right joystick controls stick and bucket.
Job Site Locations:
The working environment heavily influences machine choice:
- Tight Spaces: Require smaller machines, potentially with zero-tail swing, that can still deliver necessary power.
- Digging Depth and Breakout Force: Evaluate the required depth and the type of material (soil, rock, concrete) to determine the necessary power and attachments. Different soil types dictate power, depth, and required accessories.
Cost:
The decision between new or used significantly impacts cost.
- New Excavator Prices: Range from $20,000 to $35,000 for compact models to $250,000 to $1,000,000+ for large excavators.
- Used Excavator Prices: Generally more affordable, with compact models ranging from $10,000 to $50,000 and large models from $150,000 to $700,000+.
- Rental: An option for infrequent use. Rental rates typically range from $2,000 to $10,000 per month, depending on size and type. Many rental companies offer delivery.
- Leasing: Offers access to needed equipment for longer periods at potentially more affordable monthly payments than rentals. However, the lessee is typically responsible for maintenance and transportation costs.
Trends in Excavator Technology:
Modern excavator advancements focus on improving performance, operator comfort, and environmental impact.
- Controls: Ergonomic improvements in joysticks enhance operator comfort and productivity, leading to faster work speeds, higher hydraulic flow rates, better fuel efficiency, and reduced stalling. All controls are typically on two levers: the left for swing and stick, and the right for bucket and boom (for ISO controls).
- Ergonomics: Manufacturers are prioritizing operator well-being with:
- Adjustable armrests, seat height, and lumbar support.
- Climate-controlled, heated, and padded cabs.
- Improved cab access with wider ladders, recessed steps, and platforms.
These features increase operator comfort and productivity, leading to higher quality work.
- Tier IV Engines and Clean Diesel Fuel Technology: The EPA’s stringent emission standards (Tier IV, starting 2011, with nitrogen oxide focus in 2014) have driven the adoption of cleaner diesel technology. This three-part system involves ultra-low sulfur diesel fuel, advanced engines, and emissions control technology. This reduces carbon footprint and improves fuel efficiency. Compliance is increasingly demanded by clients, especially in the government sector, impacting a company’s ability to bid on new work.
Types of Excavators (Detailed):
While versatile, each excavator type has specific features making it ideal for certain tasks:
- Compact Excavators (Mini Excavators):
- Weight: Under 6 metric tons (e.g., around 1-ton minimum).
- Dig Depth: Typically 0 to 6 feet.
- Features: Small undercarriage width, zero-tail swing, backfill blade, independent boom swing.
- Uses: Landscaping, light construction, forestry, working in tight spaces.
- New Price Range: $20,000 – $35,000.
- Crawler Excavators:
- Weight: 6 to 90 metric tons (commonly up to 40 tons).
- Uses: Digging trenches, lifting pipes, heavy-duty construction.
- Features: Excellent balance and stability on rough terrain, less prone to getting stuck.
- New Price Range: $100,000 – $500,000.
- Dragline Excavators:
- Weight: Up to 10 metric tons (or significantly larger, over 800 tons for specialized mining).
- Uses: Civil engineering, surface mining, large excavation projects (roads, coal extraction, quarries).
- Operation: Bucket is dropped, dragged along the surface, lifted when full, swung, and emptied by releasing the drag line.
- New Price Range: $210,000 – $650,000.
- Long Reach Excavators:
- Reach: Extended arm (40 to 100 feet).
- Uses: Dredging waterways, reaching low, hard-to-access places.
- Features: Lower center of gravity in the counterweight for stability at extended reach.
- Note: Distinct from “high reach excavators” used in demolition, which have restricted operating radii due to high side-twisting forces from demolition attachments.
- New Price Range: $150,000 – $450,000.
- Suction Excavators:
- Weight: 7 to 32 metric tons.
- HP: Up to nearly 400 HP.
- Uses: Preferred by utility companies for precise material removal around sensitive underground infrastructure, reducing damage by over 50%.
- Operation: Uses 1-foot wide pipes and suction to remove material. Operators can control suction from the cab.
- New Price Range: $250,000 – $600,000.
New vs. Used Excavators:
- New: Driven by EPA Tier 4 requirements, new models are more fuel-efficient, operator-friendly, and come with full warranties. Clients, especially in government sectors, increasingly demand compliant equipment.
- Used: Still a viable option, offering affordability and dependability. Many sellers provide maintenance reports and inspection sheets for transparency. Used excavator warranties typically cover powertrain and hydraulics for periods like 3 years or 5,000 hours.
Specifications to Compare:
Before purchasing, compare these specifications to ensure the model meets job requirements:
- Dig Depth: Maximum vertical reach for excavation. Calculate your typical range to avoid overspending on excess depth. Deeper dig depth impacts price due to increased engine power and counterweight needs (e.g., every foot of added depth in crawler excavators can increase price by 8%).
- Dump Height/Bucket Capacity:
- Dump Height: Crucial if materials are being loaded onto trucks. Compact excavators typically have max dump heights of 13 feet, while crawlers can exceed 30 feet.
- Bucket Capacity: Impacts material volume moved per pass. Larger capacity speeds up large projects; smaller capacity allows for precision.
- Weight:
- Surface Damage: Lighter excavators minimize damage to sensitive surfaces (e.g., in landscaping).
- Operating Weight (Counterweight): The maximum load the excavator can handle at the end of its boom. The excavator’s information plate specifies minimum and maximum operating weights.
- Size (Job Site Context):
- Consider tight spaces, turning radius needs, open field work, transport capabilities (larger excavators require larger trailers), and terrain type.
- Engine Power:
- Engine power is directly linked to dig depth, weight, and size.
- Compact (Under 20 tons): 95 – 120 HP
- Crawler (20-40 tons): 150 – 275 HP
- Heavy (Above 40 tons): 367 – 532 HP
- Choosing the minimum horsepower to meet job requirements saves on initial cost and long-term fuel and maintenance expenses.
Attachments:
Attachments significantly increase an excavator’s versatility and productivity. Quick coupling links and universal hydraulic links facilitate seamless switching between tasks.
| Light Duty | Price | Heavy Duty | Price | Landscaping | Price |
| Auger | $200 | Auger (with teeth) | $400 | Bucket | $300 |
| Bucket | $400 | Breaker | $1,000 | Clamp | $350 |
| Clamp | $450 | Bucket | $2,500 | Flail Mower | $600 |
| Grading Blade | $750 | Grading Blade | $2,500 | Grading Blade | $700 |
| Grapple | $600 | Grapple | $800 |
Other popular heavy construction attachments:
- Couplers: Speed up attachment changes.
- Hydra Tilt Swing: Allows the bucket to angle 30 degrees to either side for slopes, ditch cleaning, grading.
- Thumbs: Work with the bucket to pick up and hold materials like broken concrete.
- Rakes: Separate debris, can angle up to 25 degrees, and can also level, fill, and grade.
- Rippers: Penetrate frost, frozen, or hard ground (shale, limestone).
- Plate Compactor: Attaches in place of the bucket to compact soil in trenches.
Optional features (some available aftermarket for $400-$1,500, with potential monthly fees for monitoring):
- Monitoring Systems: Track operations, fuel, geofence infractions, idle hours, and schedule preventative maintenance.
- Power Boost Modes: Provide extra hydraulic muscle via a joystick button.
- Angled Backfill Blade: Allows pushing materials to the side with fewer passes.
- Climate-Controlled Cabs: Enhance operator comfort in extreme temperatures.
- Anti-Vandalism Features: Include locks, cab guards, and location tracking.
Choosing a Quality Dealer:
Selecting a knowledgeable dealer is as important as choosing the right excavator. Ask these questions:
- Training: Inquire about operator training options (on-site, facility-based, or courses).
- Maintenance: Ask about routine maintenance requirements, where service can be performed (field, your shop, dealer’s location), and how to avoid voiding warranties.
- Typical Maintenance Schedule:
| Service Interval | Description | Service Action |
| :————— | :—————————— | :————————————————- |
| 10 hours | Fluids (hydraulic, engine, radiator) | Check and add fluids |
| 50 hours | Track Tension | Check and adjust |
| 250 hours | Battery | Check and clean |
| 500 hours | Engine Oil and Filter | Change |
| 1,000 hours | Swing Reduction Gear Case | Change |
| 2,000 hours | Radiator Coolant | Change |
| 5,000 hours | Hydraulic Oil | Change |
The dealer should provide a comprehensive, model-specific maintenance list.
- Typical Maintenance Schedule:
- Support and Warranties:
- Does the dealer offer on-site service for immediate needs?
- Do they stock parts for your model? (Downtime is costly).
- New Excavator Warranty: Typically full coverage for 3 years or 3,000 hours, whichever comes first (may vary by manufacturer, some offer 4 years/4,000 hours).
- Used Excavator Warranty: Often covers powertrain and hydraulics for an average of 3 years or 5,000 hours (can vary by dealer/model, some offer 1 year/500 hours on qualifying machines).
By carefully considering these factors, you can make an informed decision and acquire an excavator that perfectly suits your operational needs and budget.