521B

The new B Series track feller bunchers feature smoother hydraulic performance, increased engine HP, a more comfortable operator station and better right side operator visibility. The Cat 521B Series are zero tail swing machines designed for medium to high production clear cut and or select cut on rough terrain. These machines perform in a variety of small through larger tree size applications. A robust undercarriage utilizes proven components, customized for demanding forestry conditions. The unique boom design provides industry leading lift capacity throughout full reach range, a benefit in large timber.


SPECIFICATIONS
Engine
Gross Power 303 HP


Hydraulic System
Pumps (1) Dedicated variable displacement pump for travel circuit - 200 cc
Pumps (2) Dedicated variable displacement pump for boom and implement functions - 200 cc
Pumps (3) Electric hydraulic oil fill pump


Operating Specifications
Maximum Reach - With Head 32.5 ft


Service Refill Capacities
Cooling System 10.8 gal (US)
Engine Oil 10.3 gal (US)
Hydraulic System 118 gal (US)
Swing Drive 2.6 gal (US)
Fuel Capacity 226 gal (US)


Weights
Operating Weight - Without Head 59450 lb


Standards
Cab Cab meets FOPS/OPS/ROPS/WCB/OR-OSHA requirements


Undercarriage
Pitch 8.5 in
Size 330 EX (D7)


Power Train
Displacement 537 in³
Engine Model Cat® C9 ACERT™
Gross Power 303 HP
Gross Power - 1,800 rpm 303 HP
Rated Power - 2,100 rpm 282 HP


Boom System
Track Harvester Configuration - Lift Over Front of Tracks: Bare Pin Lift at Maximum Reach - Without Head 4000 kg @ 9.8 m (8,800 lb @ 32 ft 5 in)
Track Harvester Configuration - Lift Over Front of Tracks: Maximum Reach - With head 32.5 ft


Operating Weights - Without Heads, Standard Counterweight
Track Harvester Configuration - 521B 59450 lb


Track Gauge
521B 102 in


Track Length
Track Length 191.1 in


Ground Clearance
Ground Clearance 35 in


Tractive Effort
521B 70500 lb


BENEFITS & FEATURES
Power Train


Powerful Performance
The Cat C9 electronically controlled ACERT engine delivers power while meeting all current U.S. EPA emission standards. All models contain a fuel/water separator, engine air intake heater and a dual-stage combination air cleaner with precleaner.

High Capacity Cooling System
The side-by-side radiator/oil cooler gives excellent cooling capacity for high production bunching and harvesting. On-demand Flexxaire fan activates only when required and allows the cooling fan to purge debris from the radiator area, keeping a cleaner cooling system. The IQAN control system automatically adjusts the Flexxaire fan blade angle, reducing horsepower demand and lowering fuel consumption. The purge cycle frequency and duration can be set by operator in the cab to suit varying application conditions.

Engine Oil
Cat engine oil is formulated to optimize engine life and performance and is recommended for use in Cat diesel engines. Extended oil change intervals reduce maintenance and machine downtime.

Service
The clamshell style engine compartment provides easy access to all filters, oil dipstick, coolant reservoir, hydraulic fill pump, valves and hoses reducing maintenance time.

Service


Low Exhaust Emissions
The Cat C9 ACERT engine is a low emission engine designed to meet U.S. EPA emission regulations.

Batteries
An optional starting aid for colder climates is available for 521B machine models. This option provides two (2) additional batteries and HD battery cables.

Hydraulic Packages


Electric Hydraulic Oil Fill Pump
An easy accessible service wand allows hydraulic oil to be pumped through the hydraulic filtering system and into the tank. This reduces maintenance downtime and helps to maintain oil cleanliness requirements.

Variable Displacement Pump
521B track feller bunchers are equipped with variable displacement pumps for travel and implement functions. Hydraulics for dangle harvesting or processor heads are available for all models.

Cat Hydraulic Oil
Provides maximum protection against mechanical and corrosive wear in all hydraulic systems. Its high zinc content reduces wear and extends pump life. Biodegradable hydraulic oil (HEES) is also available from your Cat dealer and provides an environmentally-sound alternative to mineral based oils.

ToughGuard™ Hoses
Abrasion resistant hoses along the boom and stick provide strength and flexibility. The ToughGuard cover consists of a thin layer of UHMW polyethylene bonded to the rubber cover, providing exceptional abrasion resistance.

ToughGuard™ Hoses


Operator Station


Operator Comfort
The operator station is designed with joysticks and an air ride seat, reducing operator fatigue and providing easy operation. An HVAC system with updated air ducts provides better cooling and heating. A large side window with side screen allows fresh air into the cab, and an isolated mounted cab and engine reduces noise levels and vibration. Ergonomically located pedals with side-by-side foot rests provide operator comfort while operating machine travel.

Operator Comfort


Visibility
The cab design optimizes post structures and window placement to provide excellent operator visibility to front, sides and rear. A large polycarbonate skylight provides excellent upward visibility.

Visibility


Safety
The standard 32 mm (1.25 in) thick “Margard” front window maximizes operator protection. All purpose built forestry cabs meet FOPS/ROPS/OPS/WCB, OR-OSHA requirements. The skylight provides an alternate escape hatch.

Safety


Monitor
The IQAN MD3 display allows the operator to continuously monitor the operating system of the machine. The monitor has been downsized slightly to improve the operator's line of sight out the right front corner of the cab. The IQAN control system allows the operator to adjust all control parameters.

Monitor


Electrical System
The B Series track feller bunchers feature dual in-cab 12 volt power points and one 24 volt power point. Power is provided by two 12 volt maintenance free batteries and 95 amp alternator. An optional cold weather starting attachment may be selected to provide two additional batteries and HD starter cables.

Undercarriage


Undercarriage
The 521B Series machines utilize larger 330 size components providing extended life and reduced O&O costs.

Travel Motor
The proven final drives and travel motors provide up to 31 978 kg (70,500 lb) of tractive effort as standard on the 521B, giving excellent traction and power to the ground. Three (3) travel speed range selections are standard.

Track Guards
All models feature full length track guards to maximize shoe support in all types of terrain.

Carbody
The 521B model features a welded track frame to carbody design with a fixed gauge, simplifying and reducing carbody weight. The 521B provides maximum ground clearance and a smooth carbody under-surface to resist snagging on debris or large obstacles. The precision welded track frames reduce flexing and increase the durability of rollers and track links throughout the life of the machine.

Carrier Rollers
B Series models offer a choice of either standard single flange carrier rollers for moderate terrain and warm climates or star carrier rollers for severe terrain and cold climate applications. Nine bottom track rollers are used per side.

Carrier Rollers


Boom and Stick


Boom and Stick
The track harvester configuration delivers the same high performance with 4000 kg (8,800 lb) of bare pin lift capacity and 9.9 m (32 ft 6 in) of maximum reach.

Sustainability


The B Series track feller bunchers are designed to maximize efficiency and productivity while conserving natural resources.
  • The C9 ACERT engine meets all current U.S. EPA emission standards.
  • The IQAN control system automatically adjusts the Flexxaire fan blade angle, reducing horsepower demand and lowering fuel consumption.
  • Major structures and components are built to be rebuilt, reducing waste and replacement costs.

Serviceability


Extended Service Intervals
Caterpillar service and maintenance intervals have been extended to reduce machine service time, increase machine availability and reduce operating costs. Hydraulic oil change intervals can be extended from 2,000 hours to 4,000 hours. Engine coolant change intervals are 12,000 hour with Cat Extended Life Coolant/Anti-freeze. Regularly scheduled maintenance extends machine service life and lowers overall operating costs. 500-hour oil change interval reduces overall maintenance costs.

Flexxaire Fan
Standard Flexxaire fan automatically adjusts the fan blade pitch to optimize cooling and reduce fuel consumption. The reversing purge debris cycle frequency and duration can be set by operator in the cab to suit varying application conditions.

Clam-Shell Service Door
The hydraulically actuated clam-shell service door provides easy and quick access, reducing maintenance downtime.

Clam-Shell Service Door


Customer Support


Caterpillar is known the world over for the quality of customer support from its dealer network - the industry's best. No matter where you are, the expertise of a Cat dealer is always nearby. Your local Cat dealer is your forestry consultant who can recommend the machines, work tools and services to maximize your operation and provide the support to keep you at top productivity.
  • 24-hour parts availability, where and when you need them, to minimize expensive downtime.
  • Remanufactured parts that carry the same warranty as new parts at a reduced cost.
  • Operator training to get the most out of your Cat equipment.
  • Field services to provide on-site help when needed.
  • Timely repair and replacement services.
  • Customer Support Agreements to lower your operating costs.
  • State-of-the-art diagnostic programs, such as S·O·SSM oil analysis, inspection services and trend reporting to help avoid unscheduled repairs.
  • Financing programs for buying, renting or leasing Cat equipment.
  • Cat Access Account, a fast and convenient way to pay for or rent anything offered at any Cat dealer or The Cat Rental Store.
  • Cat Insurance to cover equipment losses from theft, collision, flood, upset or overturn, fire, vandalism and more.
  • Product Link™ to manage your equipment fleet through remote monitoring.
  • Cat Certified Rebuild to get a second life from your equipment.
For more information on Cat products, dealer services and industry solutions, visit www.cat.com.

EQUIPMENT
Standard Equipment

ELECTRICAL
  • 24 volt electrical system
  • Two 12 volt maintenance free batteries with 950 CCA
  • 95 Amp alternator
  • IQAN programmable controls
  • MD3 monitor display screen
GUARDS
  • Hydraulically actuated hinged engine enclosure with warning alarm
  • Engine fan guard
  • Bottom guards
  • Isolation mounted cab and engine
  • Heavy duty radiator guard door
OPERATOR ENVIRONMENT
  • OPS/FOPS/ROPS/WCB/OR-OSHA certified cab
  • Dual joystick control
  • Reverse slope windshield
  • Air ride seat
  • Skylight - alternate escape hatch
  • Top escape hatch
  • 76.2 mm (3 in) retractable seat belt
  • DIN mount radio ready with speakers
  • Operator sound suppression to standards
  • Travel alarm
  • Cup holders (2)
  • Two 12 volt and one 24 volt power outlets
  • Front window, 32 mm (1.25 in) thick Margard
  • Positive filtered ventilation, pressurized cab with bi-level air conditioner, heater and defroster with manual control
  • Left side fresh air window with screen
  • Forced air fan
  • Washable floor mat
  • Neutral lever (lockout) for all controls
POWER TRAIN
  • C9 ACERT engine meets U.S. EPA emission standards
  • Variable travel speed (3 ranges)
  • Under hood primary air filter
  • 43° C (109° F) degree ambient temperature cooling package: - Aluminum core ATAAC and side-by-side radiator and oil cooler - Removable debris screen - Swing out A/C condenser
  • Electric fuel priming pump
  • Fuel water separator
UNDERCARRIAGE
  • Track roller guards with access holes
  • Hydraulic track adjusters
  • Double flange track rollers
  • GFT80 Lohmann final drives
  • Cat 330 size undercarriage components
  • Nine (9) track rollers and two (2) carrier rollers per side
  • Welded, non-leveling carbody
HYDRAULICS
  • Dedicated fixed displacement pilot pump
  • Dedicated variable displacement pumps for track and implement functions
  • 325 EX swing drive and swing motor
  • Electric hydraulic oil fill pump
  • 265 L (70 gal) hydraulic tank
ANTIFREEZE
  • 50% concentration extended life coolant
OTHER STANDARD EQUIPMENT
  • Heavy duty hood enclosure
  • Flexxaire fan
  • Vandalism protection
  • Spare hose storage area
  • Grease gun bracket and storage area
  • 856 L (226 gal) fuel tank

Optional Equipment

LINKAGES
  • Harvester Long
  • Omission - Linkage
HYDRAULICS
  • Harvester
TRACK SYSTEMS
  • 610 mm (24 in) SG pads, clipped corners, with mud/snow reliefs
  • 711 mm (28 in) SG pads, clipped corners, with mud/snow reliefs
  • 711 mm (28 in) DG pads, clipped corners, with mud/snow reliefs
  • 914 mm (36 in) Tri-track, clipped corners, with mud/snow reliefs
  • Star Carrier Rollers
  • Standard Carrier Rollers
OTHER EQUIPMENT
  • Lighting Gp-HID, replaces certain standard lights
  • Heavy Counterweight
  • Starting Aid, Cold Weather - includes two additional batteries
  • Starting Aid, Arctic - includes engine and hydraulic oil Arctic heater
FIELD INSTALLED ATTACHMENTS
  • Skylight, peaked, removable