Warehouse Operations
Missions of a Warehouse
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Location: Near the manufacturer/Point of manufacture |
Location: Central to production locations/Customer base |
Location: Local area/Close to customer |
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Demand: Monthly/Quarterly replenishment of stocks |
Demand: Weekly/Monthly orders |
Demand: Daily |
Figure 1. Warehouse roles within the distribution network
Functions in the Warehouse:
Although it is easy to think of a warehouse as being dominated by product storage, there are many activities that occur as part of the process of getting material into and out of the warehouse.
Figure 2. Typical warehouse functions and flows
Typical warehouse functions are as follows:
Receiving (Collection of activities involved in orderly receipt of all materials coming into the warehouse; providing the assurance that the quantity and quality of such materials are as ordered; disbursing materials to storage or to other organizational functions requiring them)
Prepackaging (Performed when the products are received in bulk from a supplier and subsequently packaged singly, in merchandisable quantities, or in combinations with other parts to form kits or assortments. An entire receipt of merchandise may be processed at once, or a portion may be held in bulk form to be processed later.
Put-away (Act of placing merchandise in storage. It includes transportation and placement.)
Storage (Physical containment of merchandise while it is awaiting a demand. The form of storage may depend on the size and quantity of the items in inventory and the handling characteristics of the product or its container.)
Order picking (The process of removing items from storage to meet a specific demand)
Packaging and/or pricing (An optional step which may be used after the picking process. Individual items or assortments are boxed for more convenient use. Waiting until after picking to perform the packaging and pricing process provides flexibility in the use of on-hand inventory and eliminates the repricing activity as price lists change while merchandise sits in inventory.)
Sortation and/or accumulation (Sortation is the conversion of batch picks into individual orders. Accumulation is the process of gathering all the items that are part of an order.)
Packing and shipping (Include checking orders for completeness; packaging merchandise in an appropriate shipping container; preparing shipping documents; weighing orders to determine shipping charges; loading trucks)
Cross-docking (Shipping directly from the receiving docks)
Replenishment (Transferring items from reserve storage locations to primary picking locations)
Receiving and Shipping:
Receiving and shipping are two separate departments , but have similar personnel, equipment and space requirements. The receiving department is the start of the material flow, while the shipping department is the end of the material flow within a warehouse. The placement of the receiving and shipping department has a significant effect on the flow of material in the plant. Receiving and shipping departments could be placed next to each other or across the plant from each other. A key decision in designing the receiving and shipping functions is whether or not to centralize these two functions. The location of receiving and shipping depends on access to transportation facilities.
Figure 3
Figure 4
Figure 5
Figure 6
Advantages of Centralized Shipping and Receiving :
Common equipment
Common personnel
Improved space utilization
Disadvantages of Centralized Shipping and Receiving :
Space congestion
Lost materials
Errors in material flow direction (Example: Shipping out newly received parts by mistake)
Receiving and Shipping Space Planning:
Determine:
what is to be received and shipped
number of docks to be used
type of docks to be used
parking space requirement for trucks at the shipping/receiving areas
staging area requirement
Truck access to the Property:
The first consideration in designing the proper dock configuration is the flow of carriers about the facility. For truck access, truck traffic patterns must be analyzed and the following guidelines should be taken into consideration :
1. Two-directional service roads should be at least 24 ft wide,
2. One-way service roads should be at least 12 ft wide,
3. If pedestrian travel is to be along the service roads, a 4 -ft wide walk physically separated from the service road should be included,
4. All right angle intersections must have a minimum of a 50 ft radius,
5. Truck waiting areas should be allocated adjacent to the dock apron of sufficient magnitude to hold the maximum expected number of trucks waiting at any given time.
Figure 7. 90 o Dock configuration
Figure 8. 45 o Finger dock configuration
Space requirement for a 90 o dock is illustrated in Figure 7. If adequate apron depth does not exist for a 90 o dock, a finger dock must be utilized. 90 o docks require greater apron depth but less bay width. Dock widths may vary from 10 ft to 14 feet. The most common dock width is 12 ft. For extremely busy docks use 14 ft width. Table 1 shows the space requirements for a 12 ft wide dock with 90 o parking.
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Truck length (ft) |
Apron Depth (ft) |
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40 |
43 |
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45 |
49 |
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50 |
57 |
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55 |
63 |
Table 1. Space requirements for 90 0 docks for 12 ft wide docks.
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Finger Angle (Degrees) |
Apron Depth (ft) |
Bay Width (ft) |
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10 |
49 |
66 |
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30 |
74 |
62 |
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45 |
92 |
54 |
Table 2. Finger dock space requirements for a 65 ft trailer. (Dock width = 12 ft)
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Last Update: July 27, 1999 |
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Prepared by : Serdar Z. Elgun |
