- Jul 02, 2025
- Case Studies
Hydraulic Grabs and Electromagnet to Saudi Arabia
Discover high-quality hydraulic grabs and electromagnets designed for steel plants in Saudi Arabia. Enhance your operational efficiency and productivity with our advanced solutions tailored for the steel industry.
A large steel manufacturing plant in Jubail Industrial City, Saudi Arabia, turns scrap metal and steel billets into finished products. The plant is open around the clock, handling bulk scrap inbound and steel plate outbound. Efficient material handling is crucial, as the plant transports up to 1000 tonnes of scrap each day from storage yards to electric arc furnaces. Overhead cranes and lifting attachments must function dependably in tough outside situations, high temperatures, and high cycle counts.
The customer required specialized lifting accessories for their current overhead crane, including hydraulic grabs for handling loose scrap and an electromagnet for moving steel sheets and plate bundles. These attachments would replace old grabs and forklifts, boosting productivity and safety.
Hydraulic Grabs: Customer's Lifting Need and Pre‑Installation Challenges
Bulk scrap handling provides distinct issues requiring both high capacity and severe safety precautions. Before installation, the customer's yard used old grabs and front-end loaders to feed its melting furnaces. These methods struggled to meet output targets while exposing workers to considerable dangers. The plant's pre-installation conditions and special requirements influenced the design of the grab attachment, as detailed below.
1. Hydraulic Grabs: Scrap Handling Requirements
The yard collects shredded and chunk steel scrap up to 6m high. Small motorized grabs fitted atop loaders scooped just 1 m³ of material per cycle. Moving enough scrap for a single furnace charge requires many passes, causing scrap loading durations to exceed acceptable limits and bottleneck furnace utilization. Each loader run also required two workers—one to drive and one to serve as a spotter under rigorous safety protocols—which increased labor costs. The abrasive quality of steel scrap required loader repair every 200 hours, resulting in frequent and unplanned downtime. Manual handling posed its own risks: a slippery fragment could fall from a height, denting furnace hoods or hurting crew members.
2. Hydraulic Grab Pre‑Installation Problems
Using a hydraulic grab installed on an overhead crane can improve scrap-handling operations by increasing reach, protecting infrastructure, and regulating feed rates. Prior to the renovation, the plant's front-end loaders battled with uneven scrap piles, resulting in frequent disruptions. The pre-installation concerns necessitated the switch to a dedicated overhead crane grab system, as shown below.
1. Limited Reach
Front-end loaders used bucket geometry and wheelbase to access scrap piles. Loader buckets were unable to reach the middle of mounds taller than 4 m or with steep sides. Operators used loose scrap to build manual ramps, increasing the risk of slips and injuries from shards.
2. Damage to Infrastructure
Loader buckets with high-strength steel teeth damaged subsurface pipelines and concrete while searching for scrap. The repeated collisions harmed crane runway supports and trench coverings used for utilities. Maintenance crews need to spend extra time on patching concrete and replacing damaged pipe segments.
3. High Downtime
Abrasive metal pieces accelerated the wear of loader bucket teeth and cutting edges. Staff will need to replace parts or make repairs every so often, which increases fertilizer handling time somewhat.
4. Inconsistent Loads
The density and composition of mixed scrap can vary significantly. Loader operators often overfilled buckets with dense cast iron, exceeding safe handling restrictions, or underfilled them with low-density turnings, causing the furnace to starve. These oscillations made it impossible for process engineers to maintain a consistent feed rate, resulting in temperature swings in the melting furnace and an increase in energy usage of up to 8%.
Hydraulic Grabs: Product Design and Engineering
1. Hydraulic Grab Attachment: Structural Design
Yuantai engineered a double‑tine hydraulic grab with the following key specifications:
| Parameter | Specification |
|---|---|
| Rated Capacity | 3 tonnes per cycle |
| Volume | 1.8 m³ |
| Tine Length | 1.2 m |
| Material | Hardox 450 abrasion‑resistant steel |
| Hydraulic Flow | 80 L/min at 250 bar |
| Cylinder | Double‑acting, 150 mm bore, 80 mm rod |
| Mounting | Universal hook‑type coupling for overhead cranes |
| Weight | 1 200 kg (grab body) + 400 kg (hydraulic unit) |
The drop‑forged tines are easily replaceable, and the grab features a self‑draining hydraulic circuit to prevent fluid contamination by scrap debris. Each cylinder includes a hard‑chrome rod and integrated cushions to reduce impact at end travel and prolong seal life.
2. Hydraulic Grab: Hydraulic System and Control
The hydraulic system gives you precise, reliable control of the grab so handling scrap is faster, safer, and cleaner. The core is a compact powerpack mounted alongside the crane trolley that houses the hydraulic reservoir, filtration and cooling circuits and the drive for the pump. A 4-way solenoid valve bank governs open/close actions and lets the control system modulate flow for smooth, stepless motion. In the cab, an electronic proportional joystick gives the operator fingertip control over the grab’s position and speed, which helps you place loads precisely. Pressure transducers feed a closed-loop control system that limits closing force to prevent overloads and to cut blade wear, and a pressure relief valve and accumulator handle peak loads safely.
Electromagnet: Customer's Flat Steel Handling Need
The customer needed a faster, safer way to move flat steel from the slitting line to blanking presses. Their plates and bundles ranged from about 1 to 5 tonnes and measured up to 3 × 1.5 m. Existing methods — hand-held magnetic lifters and forklift-mounted magnets — were slow and unreliable. Operators faced the constant risk of dropped loads if a magnet lost power. The plant wanted an overhead-crane-mounted electromagnet that would speed transfers, protect plate edges, and give the team a reliable lift with room for extra safety.
1. Electromagnet: Steel Plate Transfer Requirements
The plant also needed to move finished steel sheets and plate bundles from the slitting line to blanking presses. Each plate weighs between 1 and 5 tonnes, measuring up to 3 × 1.5 m. Manual magnetic lifters and forklift-mounted magnets were slow and unsafe, risking dropped loads if power failed. The customer required a high-strength electromagnet attachment for their overhead crane, capable of lifting up to 6 tonnes with a safety margin.
2. Pre‑Installation Plate Handling Issues
Before installing the electromagnet, lifts were unreliable and work was slow. Forklift-mounted magnets could lose power on uneven ground and drop a plate mid-move. Teams resorted to slings and shackles for many lifts, which added roughly ten minutes each time and reduced throughput. Slings also pinched and bent plate edges, raising scrap and rework.
Electromagnet: Product Design and Engineering
Electromagnet Attachment: Structural Features
Yuantai provided a 6‑ton overhead electromagnet with these specifications:
| Parameter | Specification |
|---|---|
| Rated Capacity | 6 tonnes (flat steel) |
| Diameter | 1200mm |
| Coil Type | Insulated copper winding, IP55 |
| Core Material | Silicon steel laminations |
| Mounting | Hook‑type coupling for crane trolley |
| Weight | 1500kg (magnet body) |
The electromagnet's flat face design uses 100mm thick pole shoes to ensure even magnetic flux distribution and full plate lifting capacity. Stainless steel skirts protect the plate surface from scraping.
Electromagnet Electrical System
This electrical system is designed to give you stable lifting performance and precise control when handling steel plates and similar materials. The electromagnet is powered by a 400 V, 50 Hz supply and receives power through a slip ring assembly mounted on the crane trolley, which allows smooth operation during travel and lifting. Inside the crane cab, a thyristor-based control unit manages soft magnetization and demagnetization, so the current rises and falls gradually instead of hitting the system all at once, which helps protect the crane drive and extends component life. A residual flux demagnetizer circuit ensures the load releases fully when you switch off the magnet, so plates do not cling to the magnet face and slow down your workflow. To keep daily operation safe, the system includes overload and short-circuit protection using thermal and magnetic trip units, reducing the risk of electrical damage or unexpected downtime.
Yuantai Grab and Overhead Crane
Diverse Task Handling: Operational Performance
Hydraulic Grab in Scrap Yard Operations
Once installed, the hydraulic grab improved scrap yard throughput by 45%. It lifted 2.8 tonnes of shredded scrap per cycle, reducing batch feed time to the furnace from 20 to 12 minutes. Closed‑loop force control allowed operators to contain light-flake scrap without over‑closing, avoiding hydraulic shock. The grab's heavy‑duty tines with Hardox 450 steel resisted abrasive wear, extending tine life to over 4000 operating hours between replacements.
Electromagnet in Plate Handling Lines
The electromagnet enabled single‑lift movement of 6 tonne plate bundles from slitting lines to blanking presses. Plate transfer cycles dropped from 15 to 6 minutes per bundle. Soft magnetization prevented shelling (plate edge chipping), improving product quality. The residual flux demagnetizer ensured clean release, eliminating manual striking or prying to remove plates.
Combined Use in Mixed Material Handling
In certain tasks, the plant alternates between scrap and plate handling on the same crane. Quick‑change hook‑type couplings allow operators to switch from hydraulic grab to electromagnet in under 10 minutes. This flexibility maximizes crane utilization across yard and plant areas without needing multiple cranes.
Advantages of Hydraulic Grabs and Electromagnet Solutions
Enhanced Throughput and Efficiency
Hydraulic grabs and electromagnets together reduced material handling time by 40% plant‑wide. Scrap feeding to furnaces became more consistent, improving furnace energy efficiency by 3% due to steady scrap flow. Plate handling speed increased line capacity by 35%.
Improved Safety and Reduced Risks
Automated grabs eliminated manual bridging and loader risks. Safety sensors on both attachments stop operation if load sway exceeds set limits. Since installation, the plant recorded zero lifting‑related injuries or dropped loads.
Reduced Maintenance and Operating Costs
The tines on grabs and protected coil windings on magnets minimized wear. Hydraulic components are easy‑access and use standard seals. Electromagnet coils are housed in IP55 cabinets. The plant reports 50% fewer maintenance hours compared to previous loader and magnet setups.
Scalability and Flexibility
The hook‑type coupling system allows future attachments—such as coil grabs or slab clamps—to attach to the same crane. The hydraulic powerpack and magnet control units can be relocated to other cranes if plant layout changes.
Energy Efficiency
Variable‑displacement pumps on the hydraulic grab reduce pump power draw when partial closes are needed. The electromagnet's soft‑start reduces inrush by 70%, avoiding nuisance tripping of the crane main drive.
Other Applications for Hydraulic Grabs and Electromagnets
Hydraulic grabs and electromagnets provide diverse material-handling solutions for industries outside traditional crane or hoist applications. Their capacity to handle bulk commodities and lift ferrous metals streamlines processes and increases throughput in both heavy-duty and precision-sorting applications. The following are some prominent sectors where these linkages provide considerable operational benefits.
1. Port Bulk Handling
Hydraulic grabs are used in maritime terminals to load and unload bulk commodities like coal, grain, ore, and recyclable materials. The grab’s many tines converge hydraulically to clamp irregularly shaped cargoes, then open to deliver cargo into hoppers or transport vehicles. Electromagnets supplement this by handling steel billets, scrap plate, and railway wheels without the use of slings, which reduces handling steps and speeds up vessel turnaround. Both systems work with crane control logic to automate pick-and-place cycles, enhancing safety by keeping humans away from the hold.
2. Scrap Processing Yards
Hydraulic grabs feed mixed scrap, including car bodies and industrial castings, into jumbo metal shredders and balers. Electromagnets separate ferrous metals from non-ferrous portions. The grabs' strong closing power can handle dense bundles, and the interchangeable tines adjust to various scrap sizes. Meanwhile, electromagnets placed on overhead cranes or movable gantries lift steel turns and cast iron components and deposit them on conveyor belts or in separate stockpiles. This dual-attachment approach optimizes yard throughput and provides consistent feed to downstream processing equipment.
3. Steel Service Centers
In plate and coil warehouses, electromagnets on overhead or gantry cranes transport massive steel bundles (up to 30t) from storage racks to processing lines. Precision control ensures low sway and accurate placement in slitting, leveling, or cutting machines. Hydraulic grabs provide support by removing plate offcuts, trim scraps, and mill scale from work areas and depositing them in scrap hoppers for recycling. This combination reduces manual handling, speeds up material flow, and ensures clean work areas.
4. Construction Demolition Sites
Excavators and crawler cranes use hydraulic grabs to take up concrete debris, brick, and mixed demolition rubbish, which is then sorted and loaded into trucks or crushers. Operators can manage bulkier material as well as finer particles thanks to various bucket and tine arrangements. Electromagnets placed on mobile cranes or overhead gantries then remove reinforcing steel bars imbedded in the debris. These attachments separate steel on the spot, reducing landfill volume and recovering high-value metal for recycling, lowering disposal costs.
5. Mining and Quarry Operations
In surface mines and quarries, hydraulic grabs transport overburden, huge rock boulders, and ore chunks from extraction faces to haul trucks or crusher feeds. The grabs' hydraulics provide the force required for heavy, abrasive materials. During tunnel construction and maintenance, electromagnets attached to shuttle cars or monorail systems operate underneath to move steel support beams, rails, and shotcrete mesh. Both attachments include wear-resistant metals and sealed linkages to withstand dust, moisture, and impact loads, assuring dependable performance in severe mining settings.
Conclusion
Yuantai's hydraulic grabs and magnetic attachments changed material handling in the Saudi steel sector. The adaptable hook-type connector enables for quick attachment changes and future grab or clamp installations. Aside from this plant, comparable solutions are used in ports, scrap yards, service centers, demolition sites, and mining activities. Hydraulic grabs and electromagnets are tried-and-true solutions for increasing efficiency, safety, and cost savings in industries that handle a lot of scrap or steel.
