Vertical buffer modules (VBM) and vertical lift modules (VLM) make the picking process of items seamless. They’re both automated storage and retrieval systems (AS/RS) but differ in their approach. Here are several ways these machines differ:
Technology Used
Vertical lift storage modules consist of two columns of trays that have an automated inserter/extractor positioned down the middle. This inserter/extractor moves up and down between the stored trays to retrieve items as needed. VLMs supply a production line that is efficient and accurate for order fulfillment.
Vertical buffer modules obtain an aisle in the middle of the machine that serves as a multi-segment shelving system. Using a unit controller, the machine user puts the gripper in motion to pick up bins or totes to transport them to a picking station.
Foot Traffic Saved
VLMs and VBMs measure up your facility rather than across the floor space to maximize foot traffic. Standard-sized VLM machines are roughly 5 to 15 feet wide and 7 to 10 feet deep; if trays are too deep, operators cannot reach items toward the back easily. By installing VLMs in your facility operations, you can save up to 90% of floor space, which opens up opportunities to integrate other revenue-generating machinery.
As stated above, VLMs are designed to measure up toward the ceiling rather than across your facility’s floor space. The average VLM height is between 35 to 45 feet but can reach 98 feet if needed. Before you integrate VLMs into your facility, it’s vital to consider your ceiling height, storage needs, and throughput requirements.
When it comes to VBMs, the picking station—or the turntable—on the front of the machine measures 5.8 feet wide while the unit extends an average width of 8 feet. However, VBMs can reach over 34 feet long, so they take up much more floor space than VLMs.
Compared to VLMS, VBMs offer a maximum ceiling height of 39 feet, so they’re typically longer than they are tall. This gives them more of a rectangle shape for a storage solution.
Load Capacity
Load capacity is a key factor when choosing between a VLM and a VBM. VLM trays can handle up to 2,200 pounds per tray; this storage machinery solution is ideal for maintenance and repair operations because their equipment is typically heavier than other industry equipment.
On the other hand, VMBs can only handle 77 pounds per tote. So if you’re looking for a storage solution to hold heavier items, the VLM is the better choice.
Product Mix
One of the most significant differences between the two types of machinery is how they store goods—VLMs store items in trays while VBMs store items in totes. Trays and totes vary in weight distribution, so it’s crucial to determine the size and weight of the items you want to store; this helps you decide which machine best suits your operations.
As items enter the machinery, the VLM uses a height sensor at the back of the access opening to measure how tall each stored item is. The machinery’s software directs the VLM to organize it productively to maximize storage density.
Unlike VLMs, VBMs do not maximize space density the same way. This is because VBMs handle two standard sizes, 600 x 400 mm and 640 x 440 mm, and they cannot be used interchangeably.
Throughput Efficiency
Compared to traditional methods, both the VLM and VBM systems significantly improve productivity and yield quick throughputs. Both units use a pick-to-light method that enables the workers to look and pinpoint the item they’re seeking.
Since VLM trays can have high density, the search time for items can take longer than VBM totes. In addition to higher density, the taller the VLM, the longer the throughput of item retrieval.
SWWS Provides Efficient Solutions for Storing a Wide Range of Products
For over three decades, SWWS has been helping manufacturing companies like yours optimize processes through AS/RS systems. In addition to vertical buffer modules and VLM machines, SWWS supplies other AS/RS, including:
Modula’s SLIM
Modula’s SLIM automation system is designed to build storage space toward the ceiling. However, this model is ideal for storing loose materials, small items, spare parts, and more.
Mini-Load Systems
Mini-load systems are engineered to transfer small parts quickly. With mini-load systems, you have the opportunity to store and retrieve products without worrying about the impact of your material handling equipment or order picking system.
Customized AS/RS Solutions
Do you need help finding a solution that’s best for your business? SWWS and Modula are dedicated to customizing an AS/RS solution that fits your facility’s exact needs.
Ready to take the next step toward a more efficient facility? Contact your friends at Southwest Warehouse Solutions today to get started.
