1000-70000 DWT 200-1500t/h Rail mobile Screw Ship Unloader

Continuous Discharging for 1,000–70,000 DWT Vessels

The ATXL-B rail mobile screw ship unloader walks longitudinally on the dock track and reaches every hatch through a combination of gantry travel, ±135° horizontal tower slewing, ±30° boom luffing and a vertical arm that swings 30° inward and 40° outward. This three-dimensional motion lets the feeder follow the material surface inside the hold without repositioning the vessel.

Material is lifted by the vertical screw into the horizontal screw and discharged to the shore conveying system through a sealed transfer chute. Because the material path is fully enclosed from intake shroud to discharge hopper, fugitive dust is controlled at source rather than captured after release.

Technical Specifications

Configuration Options

We configure each ATXL-B around the material, vessel mix and shore interface. The screw drive uses variable frequency control for flow modulation from 20% to 100%, with torque monitoring that adjusts feed rate automatically when bulk density changes between light materials such as fly ash and heavier clinker.

• Wear protection: hardfaced flighting at 600 Brinell hardness or bolt-on chrome carbide wear segments for abrasive materials such as petcoke, limestone or iron ore concentrate.
• Dust filtration: integrated pulse-jet baghouse with reverse air cleaning, three-stage capture at screw intake, boom transfer chute and discharge hopper; 99.95% efficiency for particles above 1 micron.
• Power transmission: cable reel or festoon system, with standby generator connection available.
• Control interface: remote monitoring for productivity tracking and predictive maintenance alerts; remote operation consoles available as an option.
• Environmental package: marine-grade epoxy coating (minimum 300 microns DFT), zinc-nickel plated fasteners, IP65 electrical enclosures for saltwater exposure.

Application Fit Across Dry Bulk Terminals

The rail mobile configuration suits terminals that need to serve multiple berths with one machine. Because the unloader travels on dock rails, it can move between unloading positions without the capital cost of fixed infrastructure at each berth.

Installation and Site Requirements

Rail foundation design is confirmed against the loads and tolerances of the ATXL-B. The four-point support bogie system distributes weight across the rail, and rail clamps engage automatically when wind speed exceeds 18 m/s.

• Rail gauge: 6,000–8,000 mm.
• Foundation load rating: minimum 30 tonnes per wheel.
• Rail straightness: ±3 mm over 10 m length; maximum gradient 0.5%.
• Wind performance: operational up to 25 m/s; stowed design withstands 55 m/s.
• Utilities: 400–690 V, 50/60 Hz three-phase supply; cable reel or festoon for power transmission.

Quality Control and Acceptance Testing

Each ATXL-B undergoes a pre-delivery factory acceptance test at 100% capacity. On-site commissioning includes an 8-hour continuous run test, and annual load testing to 110% of rated capacity is supported for classification society requirements.

Dust control validation follows EPA Method 5 for stationary sources, with achieved values verified at 100% nameplate capacity using representative material over a 4-hour continuous sampling period. Third-party validation is available.

AOTUO holds more than 100 invention, utility and appearance patents and software copyrights, and is the responsible drafting unit for industry standard JC/T 2575 "Bulk Cement Spiral Unloader". Our production workshop covers 14,000 m² with advanced testing equipment, and we operate under quality, environmental and occupational health and safety management system certificates.

Maintenance and Serviceability

Screw flighting thickness is inspected every 500 operating hours, with liner plate wear measured at 1,000-hour intervals. For cement handling, screw flight replacement typically occurs at 4,000–6,000 hours; abrasive materials such as petcoke or limestone double the inspection frequency. All wear components are field-replaceable without removing the screw assembly.

The pulse-jet baghouse uses differential pressure monitoring to trigger automatic cleaning cycles when resistance exceeds 1,200 pascals. Our service network provides 1-hour response and 6-hour solution targets, with installation, after-sales, operation and maintenance personnel supporting projects along the Belt and Road route.

Information We Use to Configure Your Solution

To prepare a configuration and quotation for the ATXL-B, we need the following project inputs. These determine capacity, wear package, dust control scope and interface design.

• Material: type, bulk density, moisture content, angle of repose, particle size distribution, temperature and abrasiveness.
• Vessel mix: DWT range, hatch dimensions, freeboard range and expected annual throughput.
• Berth layout: rail gauge, rail length, number of unloading positions, gradient and foundation load capacity.
• Shore interface: receiving conveyor capacity, discharge hopper height, power supply voltage and frequency.
• Environmental limits: dust emission target, noise limit and applicable local regulations.
• Automation scope: required control interface, remote monitoring, operator certification and spare parts strategy.

Related Equipment in Our Range

For projects that need a different mobility or capacity configuration, we also manufacture the 1000-70000 DWT 200-1500t/h Tire Mobile Screw Ship Unloader and the 600-15000 DWT 100-500t/h Fixed Screw Ship Unloader. For coal and clinker terminals, our environmentally friendly screw unloader range covers higher capacities and larger vessel sizes.

Frequently Asked Questions

What is the capacity range of the ATXL-B rail mobile screw ship unloader?

The ATXL-B is rated from 200 to 1,500 t/h based on cement bulk density of 1.2–1.5 t/m³. Actual throughput varies with material angle of repose, moisture level and particle size distribution. We confirm the working point during configuration.

Which vessel sizes can this unloader serve?

The standard configuration covers 1,000 to 70,000 DWT, from small coastal freighters through Panamax-class bulk carriers. The articulated arm geometry is matched to the hatch dimensions and freeboard range of the vessels in your trade.

How is dust controlled during unloading?

We use a three-stage capture system: primary at the screw intake shroud, secondary at the boom-to-vertical arm transfer chute, and tertiary at the discharge hopper. Each stage connects to a central pulse-jet baghouse with reverse air cleaning, maintaining emission at or below 10 mg/m³ at the stack outlet.

What maintenance intervals apply to the screw assembly?

Screw flighting thickness is inspected every 500 operating hours, and liner plate wear is measured at 1,000-hour intervals. For cement, flight replacement typically occurs at 4,000–6,000 hours. Abrasive materials double the inspection frequency. All wear parts are field-replaceable.

What power supply does the unloader require?

The ATXL-B operates on 400–690 V, 50/60 Hz three-phase supply with installed motor power of 250–400 kW depending on capacity configuration. Power is transmitted through a cable reel or festoon system, and a standby generator connection is available.

Can the unloader handle materials other than cement?

Yes. With appropriate wear components and screw geometry, the ATXL-B handles clinker, coal, grain, fly ash, mineral concentrates and other free-flowing dry bulk materials. We specify the wear package and drive settings based on the material properties you provide.