Stacker Cranes
Automated storage and retrieval system (AS/RS) for pallets designed to boost productivity and increase warehouse capacity.
The product
The stacker crane: automated, speedy, error-free storage
Stacker cranes are machines designed to store and retrieve pallets automatically. They move in length, height, and depth to load and unload goods from racking structures in a highly agile, precise manner.
Mecalux stacker cranes are equipped with state-of-the-art technology, significantly increasing warehouse productivity and maximising space utilisation to boost storage capacity. Moreover, they help reduce errors and risks associated with manual operations.
Advantages of stacker cranes in warehousing
- Increased productivity: these machines can run continuously 24/7/365. Storage and retrieval are performed in the same movement (combined cycles), making the system highly agile.
- Total automation: their autonomous operation streamlines warehouse management and eliminates errors linked to manual tasks.
- Maximum space utilisation: stacker cranes can reach up to 45 m high in aisles as narrow as 1.5 m wide.
- Double- and multi-depth: these machines can operate with high-density racking with deep channels — e.g., pallet flow racking or the Pallet Shuttle system — and with single- or double-deep racking.
- High flexibility: Mecalux’s wide range of stacker cranes allows users to tailor the system to their load capacity, height and cycle time requirements.
- Safety: stacker cranes handle pallets with extreme precision. In addition, they significantly reduce handling equipment traffic, enhancing warehouse safety.
- Comprehensive solution: Mecalux designs, manufactures, installs and commissions all AS/RS components. These include the racking, stacker cranes, conveyors, and warehouse control and management systems (WCS and WMS).
We’ve shortened the time spent on fulfilling and distributing each order
Applications of automatic stacker cranes
High-throughput system that adapts to the needs of different types of warehouses
Mecalux stacker cranes are versatile storage solutions that cater to the needs of multiple companies. They have proven their effectiveness across numerous industrial sectors, including the food, metallurgy, automotive and pharmaceutical industries.
Warehouses with high inbound/outbound volumes
Automatic stacking cranes are an ideal solution for facilities with high-turnover SKUs and constant inflows and outflows.
Companies requiring greater storage capacity
Stacker cranes make optimal use of warehouse space, both vertically and horizontally.
Cold stores
These machines can operate in negative temperatures as low as -30 °C.
Gallery
By leveraging available height and operating in narrow aisles, stacker cranes expand storage capacity
How does a stacker crane work?
Stacker cranes fully automate pallet storage and retrieval operations
A stacker crane is a machine designed to perform 3 types of movements: longitudinal (to move along the aisle lengthwise), vertical (to operate at height) and transverse (for the forks to enter the racking depth-wise to deposit or remove pallets).
Transporting the pallet to the aisle
The conveyor next to the AS/RS brings the pallet to the end of the aisle.
Pallet pick-up
The extraction system picks the pallet up and places it on the lifting cradle.
Movement along the aisle
To transport the pallet to the location assigned by the WMS software, the stacker crane moves along the aisle in a simultaneous translational (lateral) and lifting motion.
Pallet storage
The extraction system inserts the pallet into the racking to place it in the assigned location.
Retrieval of another pallet
After storing the pallet, the stacker crane moves to another position to remove a pallet (in an operation known as a combined cycle).
Pallet exit
The stacker crane moves towards the end of the aisle and places the pallet on the outgoing conveyor.
Testimonials
Automation has enabled us to enhance our storage capacity and safety, cut maintenance and personnel costs and rigorously monitor product movements.
During peak demand periods, we ship around 2,400 pallets a day. Automating our logistics operations has helped us shore up the increase in sales.
Automation has resulted in reduced logistics costs and more flexible production.
By automating our logistics centre, we’ve improved our throughput and responsiveness. We’ve also lowered operating costs and errors caused by manual management.
Case studies
Cepsa
Next-generation automated clad-rack warehouse: a sure bet to streamline of logistics processes at Cepsa
The energy company Cepsa entrusted Mecalux with the construction of a 37 m tall automated, turnkey warehouse in its lubricants production facility in the town of San Roque (Cádiz). The Mecalux Easy WMS warehouse management system has also been included in the set up, and is responsible for managing all the activities of the centre. Read more
Würth
A 100% automated, turnkey warehouse for Würth in La Rioja
The German fastener, connector and assembly component company Würth has opened a new automated clad-rack warehouse in La Rioja (Spain). This very large installation means the company can supply its Wúrth stores throughout Spain, as well as customers who have purchased tools, drill bits, nuts and bolts online. Read more
Gioseppo
Gioseppo's shoe warehouse: 1.6 million shoes and 3,500 orders a day
Gioseppo, a manufacturer and distributor of footwear and fashion accessories, has adapted its e-commerce logistics operations with Mecalux storage solutions. In Elche, Spain, the company has installed an automated warehouse in addition to multi-tier shelving and a mezzanine to fill thousands of orders. Read more
Sabarot
French canned foods producer Sabarot leaps into automation
Sabarot, a French company dedicated to the production and distribution of cereals, has centralised its logistics operations with an AS/RS for pallets. Supervised by Easy WMS warehouse management software, the AS/RS is ready to be expanded if Sabarot's future needs require this. Read more
British Sugar
British Sugar reaffirms its commitment to innovation with an AS/RS in Wissington
British Sugar, the UK’s main sugar producer, has installed an AS/RS (automated storage and retrieval system) from Mecalux in Europe’s largest sugar processing plant, producing 400,000 tonnes of sugar and 64,000 tonnes of ethanol a year. Read more
EcoWipes
EcoWipes: automated logistics, 30% jump in productivity
Cosmetic and hygiene product manufacturer EcoWipes has connected its warehouse in Poland with its production lines automatically via conveyors. It has also installed live pallet racking with a stacker crane and Movirack mobile pallet racking to optimise its storage space. Read more
Hayat Kimya
Mecalux builds one of the largest automated clad-rack warehouses in Europe
Automated stacker crane models
Wide range of stacker cranes easily adaptable to specific warehouse needs
Mecalux’s single- and twin-mast automatic stacker cranes cover a broad spectrum of requirements. Thanks to this versatility, there is a suitable model for any load capacity, construction height and necessary cycle times.
SC0 stacker crane
Ideal for facilities up to 18 m tall and with few movements. It can work with single- and double-deep racking and the Pallet Shuttle system.
SCX single-mast stacker crane
High-performance stacker crane for warehouses with high-volume inflows and outflows and up to 45 m tall. It is compatible with single- and double-deep racking and the Pallet Shuttle system.
SCX twin-mast stacker crane
Also recommended for facilities with high turnover. It differs from the single-mast model by offering greater load capacity in double-deep racking and can incorporate two lifting cradles.
SC1 stacker crane
Stacker crane up to 12 m high with an extraction system compatible only with the Pallet Shuttle.
MT0 stacker crane
Also known as an automatic trilateral stacker crane, this model is the simplest in the range. It is typically implemented to automate conventional racking up to 14 m high, previously operated using trilateral forklifts.
Components of pallet stacker cranes
The design of stacker cranes for pallets minimises the forces transmitted to their supporting framework. This prevents damage to the AS/RS racking and structure in the long term.
A stacker crane is a fully automatic high-performance machine composed of various elements. These include masts, upper and lower guide bases, a lifting cradle, an extraction system and a hoisting mechanism.
The extraction system used will vary based on the application, the type of load to be handled, the arrangement of the racking and even the operational requirements. In general, there are 3 types: telescopic forks (single- and double-deep), the Pallet Shuttle and on-board conveyors.
Mecalux stacker cranes are fitted with a set of components designed to maximise the safety of the AS/RS.
Masts
Made of high-strength steel sheet metal, these constitute the stacker crane’s main axis. The lifting cradle, which supports the pallet, travels along the masts.
Lifting cradle
This moves loads vertically and performs storage and retrieval cycles through its extraction system.
Hoisting mechanism
Device with an AC motor that drives the lifting cradle in its vertical movement.
Lower guide base
Box-shaped structure equipped with a drive wheel and a freewheel. It enables the stacker crane to move along the aisle longitudinally.
Upper guide base
Ensures the stability of the stacker crane and dampens noise and vibrations resulting from its high-speed movement.
Aisle equipment
Aisles are outfitted with a bottom guide rail, top guide rail, safety equipment, electrical supply, data transmission and positioning systems.
Electrical cabinet
Located next to the mast, this supplies the stacker crane with electrical power.
Transfer bridge
Component responsible for moving stacker cranes from one aisle to another in facilities requiring this operation. The stacker crane positions itself on the bridge, where it is anchored. Then, it moves laterally to the destination aisle, where the transfer takes place.
Curved track system
Alternative solution to the transfer bridge in which the stacker crane carries out the aisle-change manoeuvre by means of a railway-type switch.
Single-deep telescopic forks
This handling mechanism stores and retrieves pallets in single-deep racking.
Double-deep telescopic forks
This extraction system is employed for loading and unloading pallets in double-deep racking.
Pallet Shuttle
Autonomous shuttle car capable of lifting, moving and depositing pallets inside very long channels. The cradle is prepared to house the Pallet Shuttle and is equipped with motorised chains to transfer pallets from/to the incoming and outgoing conveyors.
On-board conveyor
Extraction system consisting of a platform with motorised rollers used in stacker cranes that feed pallet flow racking.
Safety features in the lifting cradle
The lifting cradle is equipped with a set of components that ensure its correct operation. They include several photocells (to verify maximum load dimensions, confirm empty locations, prevent dragging/pushing of pallets with the forks and detect the exact position of the beams), load cells (to prevent start-up in the case of overweight loads), a centring check system for forks and loads, and a webcam.
Aisle safety equipment
The aisle features various safety elements, such as the stacker crane’s safe velocity control devices and hydraulic buffers positioned at the ends of the aisles. These buffers are designed to absorb the impact generated by the stacker crane when moving at maximum speed, with the lifting cradle at its highest position and carrying the heaviest load.
Safety elements for maintenance
AS/RS stacker cranes are equipped with different safety devices to facilitate maintenance tasks. They include the cabin, anchorage points, lifeline to which the operator’s harness is attached when using the ladder, and maintenance platforms.
Safety partitioning and safety mesh
Perimeter fences delineate the stacker crane’s operating area, creating a protected space for AS/RS operations. Fall protection netting covers the sides of the racking adjacent to transit areas, preventing accidents resulting from falling goods.
Access control
Access doors and push-button pads allow safe entry into aisles for performing maintenance work. The push-button pad features a safety interlock position, and the aisle access procedure is carried out in accordance with the harmonised standard UNE-EN528.
Light curtains and high-speed doors
These safety elements are used to prevent individuals from entering through the pallet entry and exit points of the conveyor lines. The doors open only when a pallet enters or exits the AS/RS. The light curtains differentiate whether what passes through the access point is a load or a person.
Emergency stop system
This halts the operation of the stacker crane. It is activated using standardised push-buttons in the manual control positions and in specific areas of the AS/RS.
FAQs
A stacker crane is a fully automatic machine designed to store and retrieve goods from locations within a racking system.
Automating a warehouse with pallet stacker cranes offers multiple benefits. Among them are increased productivity, safe and reliable operations, error elimination and optimisation of available space thanks to their ability to work at significant heights in extremely narrow aisles. Of course, the initial investment in automatic pallet racking solutions is higher than that of conventional storage systems. However, the increased operational capacity associated with automation and the reduction in operating costs (linked to handling equipment, for example) results in a rapid return on investment.
Mecalux stacker cranes can operate with single- or double-deep racking, pallet flow racking or the Automated Pallet Shuttle system.
Mecalux’s automatic trilateral stacker cranes enable the quick and cost-effective automation of adjustable pallet racking up to 14 m high. That is, these machines can be integrated into pallet racking that was previously operated with trilateral forklifts, all without modifying the racking structure. Automating other types of conventional storage systems, however, requires the replacement of the existing structures in the facility. Mecalux advises its clients on the design and implementation of the AS/RS that bests meets their needs.
Automatic stacking cranes for pallets are primarily used to move palletised loads in storage and retrieval operations. Additionally, Mecalux offers stacker cranes for boxes. Specially designed for miniload systems, these machines handle smaller unit loads such as boxes, trays and even tyres.
Mecalux stacker cranes are configured to operate in three different modes: automatic (the usual operating mode), semi-automatic (for specific and support operations) and manual (for maintenance work). The stacker crane’s automatic mode is used to execute the commands it receives from the WMS software. For instance, it performs storage and retrieval operations, storage position changes and self-learning of AS/RS locations in this mode.
This is not essential in all scenarios. For companies requiring a relatively low turnover of goods but a high storage capacity, one stacker crane could be shared by several aisles. In such cases, aisle-changing solutions (e.g., a curved-track system or a transfer bridge) can be installed to enable the stacker crane to operate in different aisles. Nevertheless, to maximise efficiency in an AS/RS, it’s ideal to use one stacker crane per aisle.
Yes. Stacker cranes incorporate regenerators that transform the energy generated during descent and deceleration manoeuvres into electricity. This electric energy is leveraged by other elements in the AS/RS, reducing power consumption.
Absolutely. In an AS/RS, access to areas where moving equipment (i.e., stacker cranes, conveyors, etc.) operates is appropriately restricted by wire mesh partitioning and secure access doors.
Yes. Every AS/RS requires two software programs. On the one hand, the warehouse management system (WMS) supervises and controls stock and assigns each unit load a location. On the other, the warehouse control system (WCS) is responsible for sending movement instructions to the stacker crane. Mecalux can supply both software programs.
Stacker cranes can operate at heights of up to 45 m.
The maximum load capacity of the stacker crane’s cradle is 1,500 kg for single-deep racking and 1,000 kg for double-deep rack configurations. Stacker crane models equipped with two cradles increase the load capacity to 3,000 kg (1,500 kg per cradle) in single-deep racks and 2,000 kg (1,000 kg per cradle) in double-deep racking.
Stacker cranes can move at a travel speed of up to 160 m/min.
The maximum lifting speed of a stacker crane is 66 m/min unloaded and 54 m/min loaded.
Mecalux stacker cranes can work in temperatures ranging from -30 °C to +40 °C.
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