ASRS Throughput Per Hour: Synchronizing High-Speed Production with Automated Logistics

The Physics of Throughput: Beyond Simple Speed

When plant managers ask about 自動トレイ倉庫 throughput, the conversation often starts with “how fast does the crane move?” While the starack-Standard system boasts horizontal speeds of up to 240m/min and vertical speeds of 60m/min, maximum velocity is a vanity metric if not paired with acceleration and settling time.

For liquid products—such as beverages, dairy, or industrial chemicals—rapid deceleration causes “sloshing.” This liquid movement shifts the center of gravity within the pallet. If a crane stops abruptly at 30 meters high, the sway can trigger safety sensors, forcing a system fault and a manual reset. This kills throughput.

We solve this via S-Curve Acceleration logic embedded in the PLC. Instead of a linear ramp-up, the drive motors follow a sinusoidal curve for acceleration and deceleration. This ensures that a 1,000kg pallet of bottled water is moved at high speeds but stops with absolute smoothness, preventing load instability and ensuring the crane is immediately ready for the next cycle. This cycle time consistency is the foundation of reliable throughput per hour.

Calculating True System Capacity

To determine if an AS/RS can handle your peak production hours, we calculate the Composite Cycle Time. This is not a theoretical number from a brochure; it is a calculated value based on the specific X (travel) and Y (lift) coordinates of your rack design.

In a typical double-mast starack configuration handling finished goods, the throughput logic follows this structure:

Cycle Type	Description	Typical Throughput (Single Crane)
Single Cycle (SC)	The crane performs one task: either putting a pallet away (Production -> Rack) OR retrieving one (Rack -> Shipping).	28 – 35 Pallets / Hour
Dual Cycle (DC)	The crane deposits a pallet and picks up another on the return trip. This maximizes efficiency by reducing “deadheading” (empty travel).	45 – 55 Pallets / Hour

For a facility requiring 200 pallets/hour throughput, we do not simply speed up the machine. We engineer the system with the correct number of aisles (cranes) to split the load. A 5-aisle system running Dual Cycles can comfortably handle 220+ pallets per hour, providing a safety buffer for production spikes.

High Density vs. High Selectivity: The FIFO Dilemma

In the Food & Beverage industry, stock rotation is non-negotiable. You operate on strict FIFO (First-In, First-Out) or FEFO (First-Expired, First-Out) rules. However, you also have high batch quantities—producing the same SKU for an 8-hour shift.

Using a standard single-deep rack for this scenario is a waste of expensive cooled air and volume. The solution is the starack-Shuttle system. By using a satellite shuttle car that detaches from the stacker crane, we can store pallets 10-deep in a channel.

This configuration reduces the number of aisles (and cranes) required, which lowers the initial investment while maintaining high throughput for batch retrieval. When a truck arrives to pick up 33 pallets of “SKU A,” the crane stays in one position while the shuttle rapidly feeds pallets out of the deep lane. This burst-throughput capability significantly reduces truck turnaround time at the docks.

Structural Rigidity: The Hidden Variable in Speed

Why do we insist on Q355 high-strength steel and a fully bolted structure for our High Bay Warehouse solutions? It is not just for durability; it is for speed.

A welded structure or one made of lower-grade steel suffers from “whipping” or oscillation at heights above 20 meters. When the crane stops, the mast vibrates. The laser positioning system must wait for this vibration to cease (settling time) before it can extend the forks, typically adding 3-5 seconds per cycle.

The starack double-mast design minimizes this oscillation. By maintaining structural rigidity, we shave seconds off every move. Over a 24-hour operation, saving 5 seconds per cycle across 5 cranes results in hundreds of additional pallets moved per day, directly impacting your plant’s total throughput capacity.

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Frequently Asked Questions

1. Can the system handle peak shipping times that exceed production speed?
Yes. This is the primary function of the AS/RS as a buffer. While production inflow might be constant at 100 pallets/hour, shipping might spike to 300 pallets/hour between 2 PM and 4 PM. We design the crane capacity and the outbound conveyor loops to handle these shipping peaks, decoupling shipping demands from production limits.

2. How does the system handle “ugly” or leaning pallets from the production line?
Before entering the high-speed zone, every pallet passes through a Profile Gauge. If a pallet has overhang >50mm or is leaning due to poor wrapping, it is automatically rejected to a rework spur. This prevents these pallets from entering the crane aisle and causing high-altitude jams that would stop throughput.

3. What happens to throughput if one crane needs maintenance?
We typically recommend a WMS strategy that distributes stock of high-velocity SKUs across multiple aisles. If Aisle 1 is down for maintenance, the WMS automatically directs retrieval commands to Aisles 2 and 3, allowing shipping to continue with only a marginal reduction in total system throughput.

4. Is the starack system compatible with existing ERP/WMS?
Yes. The system acts as the execution arm of your SAP or Oracle system. We implement a handshake protocol where your upper-level system requests a specific batch for an outbound order, and our WCS (Warehouse Control System) determines the most efficient path to retrieve it, optimizing crane movements to minimize travel time.

5. Can we install this in an existing warehouse with low ceilings?
Throughput is maximized in vertical space. If you are limited by a standard 10m ceiling, we can deploy a multi-shuttle system or modify the facility. However, for maximum ROI, many food & beverage clients opt for a Rack Clad structure (where the rack supports the roof and walls), allowing us to build up to 40 meters on the same footprint, tripling storage density and throughput per square meter.