A project for S. P. Richards Company

This is a project to accompany the course and the book Warehouse & Distribution Science, at the Georgia Institute of Technology, by John J. BARTHOLDI, III and Steven T. HACKMAN. Everyone is welcome to use the book and materials for educational purposes, as long as all copyrights remain intact.

The company and its DC operations

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Small parts stored in 18-inch deep shelves.

P. Viehweg, Senior Vice-President for Logistics of S. P. Richards Company (SPR), visited on 04 February and described the company and some engineering goals at the Philadelphia distribution center. (His presentation is available here in ppt (8MB) or pdf (8 MB) formats.)

Here are highlights from his talk. SPR distributes wholesale office products. Each DC accepts orders until 5PM and ships overnight for next day delivery. The DC's depend on a mostly manual system because it is not clear that capital investment would generate sufficient savings.

Most of the activity in Philadelphia is in zones C and D. Zone C, on the mezzanine (upstairs), holds light-bulk items, such as briefcases. Zone D, downstairs, holds the small parts, such as pens and pencils. (As expected, Zone D holds the most items.) There are also some light-bulk items in Zone D to help complete orders within that zone.

There are four pickers and two checker/packers upstairs in Zone C; and there are eleven pickers and five checker/packers downstairs in Zone D. (During the last hour of work, everyone from Zone C comes downstairs to help complete the work in Zone D.

Each order-picker works within a single zone. He/she pushes a cart and travels a complete circuit through the main aisles of the zone, picking a batch of orders totalling about 50 pick-lines from among about 100 aisles of static shelving. Workers pick directly into final packaging. Most of the time separate boxes are packed in each zone, which means that the customer might receive multiple boxes, some of which are, strictly speaking, unnecessary. Some customers insist on reduced packaging and their orders must be sent from Zone C to Zone D for completion, which greatly increases their flow time through the system.

The project

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Light bulk stored in 30-inch deep shelves.

The Philadelphia DC is reported to be among the best in the SPR system. However they continue to look for ways to improve. They have generated the following list of possible improvements, to which I have added some thoughts to help you get started:


The company data is copyrighted and proprietary. You may use it for the purposes of this course only. (If you would like to use it for something else, please contact me to discuss.)

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Order-picking at S.P. Richards Co. On a typical trip a worker picks about 50 pick-lines out of 100+ aisles.

You can download all the data below in one monolithic database (zipped mdb format, 30M). Alternatively, you can download the following flat, tab-delimited text files, which have been exported from this database. Finally, I can provide a CD-ROM for anyone without fast internet connection.

Be sure you are aware that this, like all data, has flaws


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Order-pickers in Zone D follow the red pick-path and detour as necessary into the cross aisles. Orders start/finish at the head of the conveyor (marked by a red square).

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A pick ticket for SPR. The pick ticket number in the upper right hand-corner is the order number in the sales history above. In this example, it is 01-885584. The 01 indicates the Atlanta DC. If this pick ticket were for the Philadelphia DC it would read 23-885584. The left-most column gives the locations to be visited. This example requires picks from zones A, C, and D.

Suggested first steps