TERRA TK804 4-Ton Knuckle Boom Crane

The ideal choice depends on your specific operational environment and cargo-handling requirements:

• Telescopic Boom Crane (Stiff Boom): Utilizes a high-torque bent-axis hydraulic winch and wire-rope mechanism for precise vertical hoisting. It is engineered for long-range reach, high-altitude lifting, and precise placement (e.g., lowering loads into deep foundation trenches or erecting steel frames on tall buildings).
• Knuckle Boom Crane (Folding Boom): Features an articulated boom system that folds compactly behind the truck cab, leaving maximum space on the truck bed for cargo. Operating without a wire winch in standard configurations, it uses direct hydraulic cylinders to lift, grab, and clamp. It is highly versatile in tight urban areas, under bridge decks, and works perfectly with hydraulic attachments like brick grabs and clamshell buckets.

Truck crane tonnage is rated at its minimum working radius (usually 2 to 2.5 meters from the slewing center). As the boom extends, the maximum safe lifting capacity decreases due to gravity leverage. To select the right crane, calculate your required Lifting Moment (expressed in kN·m) using the formula below:

• 2T – 5T Series: Optimized for light-duty municipal maintenance, landscaping, and small equipment transport.
• 6.3T – 12T Series: The global industry standard for general construction, utility repairs, and brick/timber logistics.
• 14T to 200T heavy-duty series: Built for extreme industrial heavy-recovery, mining support, and large-scale machinery relocation.

Our cranes feature a universal high-strength sub-frame designed for easy mounting on world-renowned commercial truck chassis to ensure easy local maintenance. Our systems are fully compatible with chassis brands widely used in South America, the Middle East, Africa, and Central Asia, including HOWO, SHACMAN, DONGFENG, ISUZU, SCANIA, FOTON, and FAW. Depending on the crane’s weight and torque, we recommend:

• 4×2 / 6×2 Chassis: Ideal for 2T to 5T cranes.
• 6×4 Chassis: Recommended for 6.3T to 12T cranes.
• 8×4 / 10×4 Chassis: Essential for heavy-duty cranes from 14T up to 100T+ to ensure proper axle weight distribution and comply with local road regulations.

Yes. Our cranes are designed with auxiliary dual-action hydraulic lines and high-pressure flat-face quick couplers at the boom tip to power a wide variety of heavy-duty attachments, transforming your vehicle into an autonomous multi-purpose cargo machine. Popular B2B attachments include:

• Earth Augers: For rapid power line pole drilling and foundation boring.
• Timber/Scrap Grapples: For high-volume forestry and recycling logistics.
• Hydraulic Brick Clamps: Specifically tuned with constant-pressure relief valves to prevent crushing bricks during loading.
• Amphibious Clamshell Grabs: Equipped with slotted drainage valves for river dredging and municipal wastewater sludge cleanup.

Safety under load is our highest engineering priority. All TERRA cranes are equipped with redundant mechanical and hydraulic safety systems, including:

• Load Moment Indicator (LMI): Actively monitors load weight, boom angle, and extension, triggering automatic visual/audible alarms and cutting off dangerous movements before an overload occurs.
• High-Strength Hydraulic Locks: Fitted on all outrigger and lift cylinders to prevent hydraulic cylinder “drift” or sudden collapse in the event of an engine shutdown.
• Dual-Seal Two-Way Balance Valves: Provides a dual-seal barrier to securely lock the telescoping boom at any angle under full load.
• Over-Winding Alarm System: Automatically stops the bent-axis winch drum (applicable on stiff boom cranes) to prevent wire rope snapping when the hook blocks approach the boom tip.

We specifically customize our hydraulic and cooling systems to withstand the harshest climates in emerging markets:

• Tropical/Desert Package (Middle East & Africa): Equipped with a large-volume, high-power hydraulic oil radiator featuring an oversized cooling fan to keep oil temperatures below 60°C in ambient heat up to 50°C.
• Cold Climate Package (Central Asia & Russia): Outfitted with specialized low-temperature resistant hydraulic seals and high-fluidity low-pour-point hydraulic oils, allowing smooth operation down to -40°C.
• Dust & Sand Protection: The slewing bearings and cylinder rods are protected by heavy-duty wiper seals to prevent abrasive sand from penetrating the system and causing premature wear.

To maximize your payload capacity and ensure road compliance, our cranes are fabricated entirely with Premium High-Tensile Structural Steel of European-standard high-yield strength. This advanced material drastically reduces the crane’s deadweight (tare weight) while maximizing its Resisting Bending Moment (RBM). For B2B fleet operators, this means a lighter truck crane that can legally carry more cargo on the truck bed while enjoying superior structural rigidity that prevents boom twist or cracking under heavy stress.

Standard knuckle boom cranes do not use a winch drum or wire rope; they utilize direct hydraulic cylinders and heavy-duty mechanical linkages to raise and lower cargo. This design allows for extremely fast loading cycle times and precise close-range handling. However, for specialized utility construction or high-altitude rescue work, we can customize knuckle boom cranes by adding an auxiliary hydraulic bent-axis winch at the main boom tip to provide vertical wire-rope hoisting capabilities.

In many emerging markets, complex computer sensors and fragile microprocessors are the leading cause of prolonged machine downtime. TERRA cranes are engineered with robust, high-pressure, mechanically actuated control valves and heavy-duty gear/piston pumps. This robust mechanical-hydraulic design ensures high reliability under extreme workloads, allows for manual emergency overrides, and can be easily serviced by any local hydraulic technician with zero digital diagnostics tools required.