BROKEN CASE PICKING SYSTEMS

Chapter seven RightStore Pieces: Piece Picking Principles, Systems, and Best Practices

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Order-pick times for vertical carousels are theoretically less than those for horizontal carousels. The decrease results from the fact that items are always presented at an order picker’s waist level. This eliminates the stoop ing and reaching that go on with horizontal carousels, further reducing search time, and promotes more accurate picking. (Some of the gains in item extract time are negated by the slower rotation speed of the vertical carousel. Recall that the direction of rotation is against gravity.) Additional benefits provided by vertical carousels include excellent item protection and security. In vertical carousels, only one shelf of items is exposed at a time, and the entire contents of the carousel can be locked up. Vertical carousels are much more expensive than horizontal carousels with cost increasing with the number of shelves, weight capacity, and special features. The additional cost of vertical over horizontal carousels is a result of the sheet-metal enclosure and the extra power required to rotate against the force of gravity. Miniload Automated Storage and Retrieval Systems In miniload ASRSs (Figures 7.51 through 7.57), an automated storage/ retrieval machine travels horizontally and vertically simultaneously in a storage aisle, transporting storage containers to and from an order picking station located at one end of the system. The order picking station typically has two pick positions. As the order picker is picking from the container in the left pick position, the storage/retrieval machine is taking the container from the right pick position back to its location in the rack and returning with the next container. The result is that an order picker alternately picks from the left and right pick positions. The sequence of containers to be processed can be determined manually (the order picker keying in the desired line-item numbers or rack locations on a keypad) or automatically by computer control. Miniload systems vary in height from 8 to 70 feet and in length from 40 to 300 feet. As is the case with carousels, the height and length of the system are dictated by the throughput requirements and building restrictions. The longer and taller

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