312D/312D L

Achieve high productivity and lower operating costs with the Cat® 312D Hydraulic Excavator. Unmatched versatility, improved controllability, easy operation and a comfortable, redesigned operator station help make the 312D an industry-leading performer.


SPECIFICATIONS
Engine
Engine Model Cat® C4.2 ACERT™
Flywheel Power 90.0 hp
Gross Power 97.0 hp
SAE J1349 90.0 hp
Bore 4.0 in
Stroke 5.1 in
Displacement 259.0 in3
Net Power – SAE J1349 90.0 hp


Weights
Operating Weight 28480.0 lb
Operating Weight – Standard Undercarriage 28480.0 lb
Operating Weight – Long Undercarriage 29650.0 lb


Drive
Maximum Drawbar Pull 25600.0 lb
Travel Speed 3.4 mph


Swing Mechanism
Swing Torque 22830.0 lb ft
Swing Speed 12.4 RPM


Hydraulic System
Main Implement System – Maximum Flow (2x) 33.5 gal/min
Maximum Pressure – Implements 4424.0 psi
Maximum Pressure – Travel 3340.0 psi
Maximum Pressure – Swing 3336.0 psi
Pilot System – Maximum Flow 9.5 gal/min
Pilot System – Maximum Pressure 598.0 psi
Blade System - Maximum Pressure 2990.0 psi
Boom Cylinder – Bore 4.3 in
Boom Cylinder – Stroke 40.0 in
Stick Cylinder – Bore 4.7 in
Stick Cylinder – Stroke 47.1 in
Bucket Cylinder – Bore 3.9 in
Bucket Cylinder – Stroke 37.0 in


Service Refill Capacities
Fuel Tank 66.0 gal
Cooling System 4.7 gal
Engine Oil 4.6 gal
Swing Drive (each) 0.79 gal
Final Drive (each) 0.79 gal
Hydraulic System (including Tank) 27.5 gal
Hydraulic Tank 23.9 gal


Standards
Cab/FOGS SAE J1356 FEB88 ISO 10262


Dimensions
Transport width 98.0 in
Counterweight Clearance 36.0 in
Length to Center of Rollers 10.0 ft
Length to Center of Rollers - LC 10.0 ft
Length to Center of Rollers - STD 9.1 ft
Shipping Height 9.25 ft
Shipping Height - LC 9.3 ft
Shipping Height - STD 9.3 ft
Transport width - LC 8.5 ft
Transport width - STD 8.2 ft


BENEFITS & FEATURES
Operator Station
Enhanced comfort, operation and visibility


Operator Station

Experience a spacious, quiet and comfortable operator station. The cab is pressurized to 50 Pa to reduce the amount of dust that enters the cab, keeping the operator comfortable the entire shift, while assuring high productivity during long work days.
  • The comfortable seat adjusts to suit the operator's size and weight. Available as an option is the air suspension seat.
  • Standard air conditioning with automatic climate control adjusts temperature and airflow.
  • Low effort joystick controls are designed to match the operator's natural wrist and arm position. Joysticks can be operated with arms on the adjustable armrests. The horizontal and vertical strokes are designed to reduce fatigue.

Prestart Check and Monitor Display
Prior to starting the machine, the system checks for low engine oil, hydraulic oil and engine coolant fluid levels and warns the operator through a color Liquid Crystal Display (LCD) monitor. The LCD monitor displays vital operating and performance information, in 28 different languages, for operator convenience.

Cab Exterior
The 312D provides a new cab design that allows the Falling Object Guard System (FOGS) to be bolted directly to the cab, at the factory or as an attachment, enabling the machine to meet specifications and job site requirements. The cab shell is attached to the frame with viscous rubber cab mounts that dampen vibrations and sound levels to enhance operator comfort.

Machine Security System
An optional Machine Security System (MSS) utilizes a programmable key, deterring theft, vandalism and unauthorized usage. MSS uses electronically coded keys selected by the customer to limit usage by individuals or time parameters.

Engine
Delivering the most work per liter/gallon of fuel consumed


Engine

The Cat® C4.2 engine with ACERT™ Technology optimizes performance and meets U.S. EPA Tier 3 and EU Stage IIIA regulations. In conjunction with integrated electronics, ACERT Technology reduces emissions during the combustion process by using advanced technology in the air and fuel systems. The Cat C4.2 engine delivers exceptional power, allowing more hydraulic pressure to drive productivity and reduce your cost per ton of material moved.

Automatic Engine Control and Fuel Delivery
A two-stage control with one-touch command maximizes fuel efficiency and reduces sound levels. Fuel delivery is managed by the ADEM™ A4 Engine Controller for the best performance per liter (gallon) of fuel used. Flexible fuel mapping allows the engine to respond quickly to varying application needs.

Crankshaft and Pistons
A forged, one-piece, induction hardened crankshaft enhances balance, decreases vibration and improves abrasion resistance. Heat resistant, aluminum alloy pistons have a short compression height for greater efficiency and longer life.

Economy Mode
Available as standard, economy mode allows you to balance the demands of performance and fuel economy while maintaining the breakout forces and lift capacity enjoyed at standard power.

Hydraulics
Low effort and precise control for highly efficient performance


Hydraulics

Outstanding Performance
With two percent more hydraulic pressure for additional lift and breakout forces, the 312D hydraulic system is designed for high efficiency and performance. Auxiliary hydraulic and electrical lines are routed to the boom foot making installation of hydraulic circuits much easier. This compact design utilizes short tubes and lines, reducing friction and pressure drops, resulting in a more efficient use of power.
  • Hydraulic snubbers at the rod end of the boom cylinders and both ends of the stick cylinders cushion shock, reduce sound and increase cylinder life.
  • Flow is reduced to a minimum when controls are in neutral to reduce fuel consumption and extend component life.
  • Electronic Under Speed Control electronically adjusts pump output to not exceed engine power, preventing the need to reserve engine power to avoid engine stalls.
  • Hydraulic Cross-Sensing System uses two hydraulic pumps up to 100 percent of engine power under all operating conditions, improving productivity with faster implement speeds and quicker, stronger pivot turns.

Boom and Stick Regeneration Circuit
The boom and stick regeneration circuit saves energy during boom-down and stick-in operation, increasing efficiency and lowering operating costs.

Easy Operation
Work mode and power mode switches have been eliminated making full power available at all times. Operators do not need to learn different modes, an automatic boom and swing priority function automatically selects the best mode based on joystick movement.

Undercarriage/Structures
Strong, stable and easy to maneuver


Undercarriage/Structures

Caterpillar uses advanced engineering and software to analyze all structures, creating a durable, reliable machine for the toughest applications. More than 70 percent of the structural welds are robotic and achieve additional penetration over manual welds. These structural components and undercarriage are the backbone of the machine's durability.

Carbody Design
X-shaped, box section carbody provides excellent resistance to torsional bending. Robot-welded track roller frames are press-formed, pentagonal units that deliver exceptional strength and service life. Idler and center guards (standard for LC option) are available to help maintain track alignment when traveling or working on slopes.

Grease Lubricated Track
Grease lubricated track seals protect the track link and deliver long track link pin and bushing inner wear.

Travel Motors
Travel motors with automatic speed selection let the 312D automatically change up and down from high and low speeds in a smooth, controlled manner.

Front Linkage
Reliable, durable and versatile


Front Linkage

Built for performance and long service life, Cat booms and sticks are welded, box-section structures with thick multi-plate high strength steel fabrications. Service intervals are extended with self-lubricating bearings that resist corrosion and galling for superior durability.

Boom
The boom is designed for maximum digging capability and is robotic welded to ensure consistent quality. This allows excellent all-around versatility and a large working envelope.

Stick
Three stick options are available to meet your application needs and increase performance and productivity. A new 2.8 m (9'2") intermediate stick is available to provide long reach and increased digging and lifting capability.

Versatility
More options for more work


Versatility

Work Tools
Caterpillar offers a variety of work tools, including hammers, thumbs, grapples, multi-processors, shears, pulverizers and vibratory compactors to fit your application needs. Additionally, a wide range of buckets are available to optimize machine performance.Auxiliary hydraulic and electrical lines are routed to the boom foot for easier installation of auxiliary hydraulic circuits, therefore reducing time, parts and cost required to add a work tool.

Hydraulic Pin Grabber
An optional hydraulic pin grabber is available to pick up a wide variety of work tools without having to leave the cab, thus maximizing productivity.

Enhanced Systems
Work tool functionality has increased the versatility of the machine with the enhancement of the following:
  • An optional Combined System enables one or two pump flow in one or two directions. With this system, only one hydraulic circuit is required.
  • The Tool Control System stores up to 10 different tool settings through the in-cab display monitor. Cat Work Tools are selectable with preset flows and pressures.
  • Offered as an option, the Priority Flow System provides one-way or two-way hydraulic work tools, such as a mower, priority for hydraulic flow.
  • Medium Pressure Circuit is available as an attachment for work tools requiring moderate hydraulic flow, such as a rotating bucket or shears.

Serviceability
Simplified service and maintenance saves time and money


Serviceability

Designed with the service technician in mind, many service locations are at ground level so critical maintenance can be done quickly and efficiently. Longer maintenance intervals reduce cost and increase machine availability.
  • LCD monitor has the capability to memorize working hours for filters, fluids, components and work tools. Working time histories and recommended change intervals can be displayed.
  • Oil level gauge, fuel filter and priming pump are conveniently located on engine structure for easy maintenance.
  • An optional electronic fuel water sensor is available to alert the operator when the water level is high.
  • Product Link assists with fleet management by tracking hours, location and product health.
  • New anti-skid plates over the top of the storage box and upper structure help prevent slipping and mud from falling into the upper structure.

Sampling Ports
Equipped with S·O·SSM sampling ports and test ports for hydraulics, engine oil and coolant for quick diagnostics. A test connection for the Cat Electronic Technician (Cat ET) service tool is not located in the cab.

Air Cleaner
A double-layered filter core in the radial seal air filter gives more efficient filtration. A warning is displayed on the monitor when dust accumulates above a preset level. This filter is conveniently located in the compartment behind the cab. An optional pre-cleaner is also available to extend filter life and reduce maintenance costs.

Capsule Filter
Capsule-type, hydraulic return filter is accessible from outside the tank and prevents contaminants from entering the system when changing the hydraulic oil.

Radiator Compartment
Horizontal air conditioner condenser swings out for easy cleaning. Removable screens are located in front of the radiator and hydraulic cooler, reducing cleaning time and effort.

Technology Products
Advanced technologies improve productivity and simplify serviceability


Technology Products

AccuGrade™ Systems
AccuGrade™ Grade Control Systems are easy to use and deliver a wide range of benefits to customers, including:
  • Increased productivity
  • Increased job-site safety
  • Assistance with labor shortages
  • Improved employee satisfaction and retention
  • Increased equipment versatility
  • Integration into Cat® machines.

AccuGrade Site Reference System
Advanced slope and elevation guidance simplifies excavation, improves accuracy, increases efficiency and lowers production costs.

AccuGrade Laser Reference System
This system builds on the Site Reference System by using laser receivers to carry benchmark information across a large job site.

AccuGrade GPS System
GPS satellites allow for precise digging and slope control in real-time for increased accuracy and productivity.

Customer Support
Unmatched support makes the difference


Customer Support

Your Cat dealer is ready to assist you with your purchase decision and everything after.
  • Make detailed comparisons of the machines you are considering before you buy with estimates of component life, preventive maintenance and the true cost of production.
  • Customize the machine that is right for you using Build and Quote applications on your dealer's website or www.cat.com.
  • Get the latest training literature and trained staff.
  • Repair option programs guarantee the cost of repairs up front.
  • Nearly all parts are available at dealer parts counters.
  • Financing packages are flexible to meet your needs.
  • Your Cat dealer can evaluate the cost involved in repairing, rebuilding and replacing your machine so you make the right choice.

EQUIPMENT
Standard Equipment

Alternator, 50 amp
Automatic engine speed control
Bolt-on Falling Object Guard System (FOGS) capability
Cab
  • • AM/FM radio, 24-volt
  • • Ashtray with cigar lighter
  • • Coat hook
  • • Beverage holder
  • • Economy mode
  • • Horn
Language display monitor (full graphic/full color display)
  • • Clock
  • • Filter/fluid change information
  • • Level check for hydraulic oil, engine oil and coolant
  • • Warning messages
Light, interior
Literature holder
Openable front windshield
Openable skylight with sun shade
Storage compartment
Travel control pedals with removable hand levers
Door locks and cap locks with one-key security system
Light, storage box mounted (1)
Mirrors (frame and cab)
Power Train
  • • Cat® C4.2 engine with ACERT™ Technology
  • • 24-volt electric starter
  • • Air intake heater
  • • Water separator
Radial seal air filter
Undercarriage
  • • Idler section track guiding guards
  • • Center section track guiding guards (for 312D L)
  • • Track-type undercarriage with grease lubricated seals

Optional Equipment

AccuGrade™ Basic, Laser and GPS ready
Air prefilter
Auxiliary hydraulics
Auxiliary hydraulic lines from booms and sticks
Boom lowering and overload warning control device
Bucket linkage
Cab mounted working lights
Cab mounted working lights with time delay function
Cold weather start
E-Ceiling and cab avoidance
Fine swing control
Front windshield gaurd
Hand control pattern changer
Heavy-duty bottom guard
High ambient cooling system
Power supply 7A-12V
Pull down sunscreen
Rain protector
Right side boom lights
Side steel bumper
Secondary exit, rear window
Stick and boom configurations
  • • 3.0 m (9'10") stick
  • • 2.8 m (9'2") stick
  • • 2.5 m (8'2")stick
Sun visor
Swivel guard
Vandalism protection
Water level indicator for water separator

CONNECT. DISCUSS. SOLVE.
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