Vertical Carousels: The Dark Horse of Order Picking
The most common vertical carousel application today is product security. With lockable doors, automated security doors and a variety of inventory management software to provide traceability, it's no wonder that the vertical carousel lends itself nicely to storing and managing high dollar value items; it's quite a nice fit.
While this is a great application, the most overlooked application for a vertical carousel is order picking. That's right, plain good old fashioned order picking. When picking orders that average 4 lines per order or more, vertical carousels with inventory management software is an ideal solution. It offers fast retrieval times, provides good throughput and minimal operator travel time.
Using inventory management software, a vertical carousel will only rotate around one time to make all picks required for an order. This means the time it takes to deliver a complete order to the operator will never be longer than the time it takes for a vertical carousel to make one full rotation. An average sized vertical carousel at 20 feet can make a complete rotation in 90 seconds. Compared to other storage technologies that require trays to be extracted, it would take up to 132 seconds to deliver four trays to an operator.
Here is where the slotting argument comes into play. Of course if you slot the storage machine efficiently and two of the four parts are located on the same tray the storage device only has to retrieve and deliver three trays, cutting down the delivery time. The same argument can be made for the vertical carousel. When slotted properly, the most frequently picked items (or fast movers) are stored on carriers that are close to one another, cutting machine delivery time.
Vertical carousels can also be programmed with a "home" location. When the machine has sat idle for a specific amount of time and no order is currently being picked it automatically rotates to the home position. This ensures that when the next order is ready to be picked the vertical carousel is already rotated to the "home" position where fast movers are stored.
Batch Picking For Improved Throughput
When integrated with software, batch order picking is possible. Batch order picking is the process of picking multiple orders (or a batch) at a time. A combination of vertical carousels, software, a batch station and pick to light technology allows an operator to batch pick. A batch station is commonly located in front of the carousels and the operator stands between the carousels and the batch station.
First, an operator assigns an order to a tote on the batch station. The software coordinates the picks so that the carousel rotates around to present the operator with the first pick and the lights direct the operator to pick a specific quantity of that SKU from the carousel. The operator picks a the quantity and turns to distribute them among the batch of orders located on the batch station. This allows the operator to fill multiple orders with only one rotation of the vertical carousel, increasing throughput substantially.
Minimal Walk Time
When order picking, it's always important to take into consideration operator walk time. A typical vertical carousel is 12 foot wide, lining up 4 vertical carousels side by side in a row can create a 48 foot area for an operator to cover. Instead, place two vertical carousels next to each other and the other two vertical carousels across from the first two. The operator then only has to walk a maximum distance of 24 feet to make a pick. When designing a vertical carousel order picking system it is important to strategically place the carousels to minimize walk time.
Making it Work in the Real World
Vertical carousels are working every day to assist organizations in picking orders. An electronic contract manufacturer based in Utah uses three 20 foot Megamat vertical carousels for order picking. The vertical carousels manage the electronic components used to produce printed circuit board assemblies. Orders are picked daily to feed the manufacturing line. The vertical carousels have pick to light technology and are equipped with FastPic inventory management software that interfaces with the companies ERP system.
When a job is ready for fulfillment, the order is downloaded from the ERP system to the FastPic inventory management software. When ready, the operator starts the order, causing the vertical carousels to spin into position for picking and the batch lights to light. The operator easily moves from one pick to another filling the job order. Most job orders contain between 100 and 150 lines.
The carousels require less people and allow the company to fill job orders faster than ever. Previously picking job orders from shelving, the company has seen not only an improvement in productivity, but an uptick in picking accuracy as well.
Kardex Remstar, LLC, a company of the Kardex Group is a leading provider of automated storage and retrieval systems for manufacturing, distribution, warehousing, offices and institutions. For information about our dynamic storage solutions, call 800-639-5805 or visit www.kardexremstar.com.