• Sep 30, 2025
• News

Overhead Crane with Clamshell Bucket and Grab Bucket

Overhead cranes equipped with clamshell or grab buckets—rated for 5–20 t—excel at handling bulk materials (e.g., coal, grain, scrap) in heavy-duty settings such as power plants and ports.

Introduction to Overhead Cranes with Clamshell and Grab Buckets

Specialized overhead cranes with clamshell or grab buckets are engineered for efficient bulk-material handling in environments like power plants, docks, and large-scale warehouses. By pairing these buckets with a double-girder design (spans up to 34.5 m), operators achieve higher cycle rates and reduced deflection—key benefits demonstrated in a recent port deployment where throughput increased by 30%.

Key Components and Features

When you explore crane options for bulk or scrap material handling, it helps to understand how each part of the system affects performance, cost, and long-term reliability. Grab overhead cranes are used in material recovery facilities, bulk-handling terminals, ports, and scrap yards. Strength, reach, repeatability, and safe material handling are all balanced in the design. Every mechanical element—from the girders to the grab bucket and control system—works together to support smooth operations and safe movement of materials. Understanding these details makes it easier to select a crane that fits your facility layout, material type, work cycle, and future expansion plans.

1. Single/Double Girder Design

A single-girder crane works well for lighter-duty operations where cost efficiency, moderate lifting height, and lower span lengths matter. It usually takes up less space and requires simpler installation. A double-girder design, however, gives you higher lifting capacities, longer spans, and a more rigid structure. Most buyers choose a double-girder system when they need improved stability during high-intensity grab work. Because double girders resist bending and twisting, they allow smoother material placement and faster cycle times. The added stiffness also supports heavy trolley assemblies, walkways, and multi-rope reeving systems without compromising safety. During installation, precise rail alignment and foundation strength are critical to ensure the crane performs as designed and avoids uneven wear.

2. Grab and Clamshell Buckets

Clamshell buckets use two hinged shells and suit free-flowing bulk like sand, grain, or fertilizer; they scoop cleanly and dump reliably. Grab buckets come in orange-peel, multi-rope, or two-shell variants and handle irregular, dense materials such as scrap, logs, or demolition debris. Hydraulic cylinders give clamshells quicker, more precise closing and opening, while hydraulic or higher-tension multi-rope grabs give up to ~30% greater bite force for compacted or heavy feed. Designers choose bucket volume, shell profile, teeth, and wear liners to match material abrasiveness and bulk density. Suspension can be single-point, multi-point, or with a spreader beam to reduce load swing. Quick-change couplings let crews swap buckets fast. Proper matching of bucket type, hoist speed, and reeving pattern keeps cycle times efficient and reduces wear.

3. Mechanisms

The hoisting system usually uses a drum or multi-part reeving with steel wire rope sized to meet rated loads and safety factors. Motors are often three-phase AC with VFDs for smooth acceleration, soft starts, and precise control of closing and lifting speeds. Gearboxes use helical or planetary gears for quiet, durable operation and carry lubrication systems and inspection ports. Brakes are designed as following: an electric or spring-applied holding brake plus a service brake to meet OSHA/industry proof-load and holding requirements. Load monitoring systems (LMI or load cells) provide real-time weight readouts and trip at preset limits. Ropes run on crowned drums and grooved sheaves to extend life. Designers fit emergency lowering systems and manual backup gear where required. Regular inspection points include rope termination, drum grooves, brake lining, gearbox oil levels, and motor temperature.

4. Safety and Control Features

Bridge and trolley travel use dual independent drives for smooth positioning. Drives typically pair VFD-controlled gear motors with helical gears and robust couplings. Anti-collision systems use radar, ultrasonic sensors, or PLC logic to prevent multiple cranes from entering the same zone. Limit switches, end-stops, and rail clamps stop travel at safe points and protect structures. Wheelsets use hardened treads and greaseable bearings; many systems include flange lubrication and automatic track cleaning for dusty yards.

Applications of Overhead Cranes with Grab Buckets

Overhead cranes fitted with clamshell or grab buckets move large volumes of loose material quickly and with control. They lift, carry, and place coal, ore, grain, scrap and similar bulk loads. Operators can open and close the bucket to scoop, hold, and release material precisely. These cranes come in many sizes and can be matched to job needs — from small workshop units to heavy-duty harbor gantries. They reduce manual handling, cut cycle times, and lower the risk of spills and damage. Controls, wear-resistant buckets, and dust-mitigation options make them safe and economical for continuous use.

1. Power Plants

In power plants, clamshell and grab buckets handle fuel delivery and ash removal with speed and reliability. The cranes unload coal from railcars or ships, move it to stockpiles, and feed conveyors or hoppers that lead to boilers. For biomass plants, buckets are shaped and lined to limit material hang-up and contamination. Features like dust enclosures, inerting systems, and sealed buckets reduce airborne particles and fire risk. Heavy-duty designs resist abrasion from coal and ash, and automation keeps the fuel feed steady to avoid boiler interruptions. Routine inspection of bucket teeth, seals, and hoist brakes helps prevent costly downtime.

2. Ports and Docks

At ports and docks, grab-equipped overhead cranes speed up ship unloading and loading of bulk cargos. They handle iron ore, coal, sand, grain and aggregates directly from a ship's hold into barges, stockpiles, or conveyor inlets. Different grab styles — clamshell, orange-peel, or multi-shell — suit different materials and moisture conditions. High-capacity grabs and fast cycle rates cut vessel turnaround time and terminal congestion. Operators use spreaders and remote controls to place loads accurately while minimizing spillage.

3. Workshops and Factories

In workshops and factories, grab buckets move irregular or bulky materials that are hard to palletize. They scoop scrap metal to feed shredders and separators. In steel mills and foundries, robust grabs transfer hot or heavy pieces safely when combined with heat-resistant liners and quick-release systems. These cranes improve workflow by placing material exactly where operators need it. Quick-change attachments let a single crane serve multiple tasks. Regular maintenance keeps seals, hydraulics, and linkages working under tough conditions.

4. Warehouses

In large warehouses and distribution centers, grab buckets handle bulk goods that are unloaded in loose form or in large sacks. They speed up movement of grain, fertilizer, wood pellets, and similar stock between dock, storage, and staging areas. Using grabs reduces the need for forklifts and manual shoveling. Systems can integrate with warehouse management and conveyors to automate batch transfers and inventory replenishment. For fragile or dusty products, soft-grip liners and enclosures protect goods and keep the space clean. Well-matched bucket size and careful operator training maximize efficiency and cut product loss.

Advantages of Overhead Cranes with Clamshell and Grab Buckets

Yuantai Overhead Cranes with Grab Buckets & Clamshell Buckets

Ask for Price

Double Girder Grab Overhead Crane

Yuantai builds heavy-duty overhead cranes fitted with clamshell and grab buckets for efficient bulk handling. These systems move coal, ore, grain, scrap and other loose materials quickly and reliably. We tailor each machine to the worksite, the material, and the workload.

1. Production materials: We manufacture main structures from Q235B and Q345B steel to give the best mix of strength and toughness for crane service. Q235B offers good ductility and weldability for fabricated parts and secondary members. Q345B provides higher yield strength and better fatigue resistance for highly stressed components like girders and end trucks. Fabrication includes precision cutting, welding to code, stress relief where needed, and strict dimensional inspection. All steel receives surface preparation such as shot-blasting, primer and finish coats, or hot-dip galvanizing on request for outdoor or corrosive environments.
2. Custom Grab Designs: We design grabs to match the material and cycle needs. Options include multi-rope grabs for large lifts, hydraulic grabs for smooth, adjustable closing force, and electric grabs for energy-efficient, low-maintenance operation. Grab shapes cover clamshell (two-shell), four-shell and orange-peel styles so you can handle free-flowing bulk, dense lumps, or scrap metal. We add wear liners, replaceable teeth, and quick-change couplings to reduce downtime. Grabs integrate with crane PLCs and controls for synchronized sequencing, auto-release, remote operation and optional live cameras or sensors to help operators work safely and faster.
3. Safety parts: Safety comes first in every design. We fit overload limiters or load cells, top and bottom travel limit switches, emergency-stop interlocks and precision control systems (VFDs and PLC control) for soft starts and anti-sway control. For outdoor use we provide weatherproof housings, covers for moving parts, sealed connectors with appropriate IP ratings, and corrosion-resistant coatings on exposed equipment. We supply inspection access points, maintenance manuals, spare parts kits and training packages. Units are designed to meet applicable international standards and to support routine NDT and inspection schedules for long, safe service life.

Conclusion

Overhead cranes equipped with clamshell and grab buckets are indispensable for industries dealing with bulk materials. These cranes can easily grab scattered goods, which greatly improves efficiency compared to manual labor. Yuantai Crane offers advanced, customizable solutions to meet diverse industrial requirements