This is part 3 of the blog entry on Stocking Policy for the Warehouse Pick Face. Part-1 was about parameters that influence stocking policy in your pick face and in Part-2, a simple approach to formulating stocking policy for the pick face was discussed.
How does it all fit in if you are using Oracle WMS to manage your distribution centers?
Pick Face Definition
The physical space that constitutes pick face in your warehouse needs to be a separate sub-inventory. The individual storage bins in the pick face can be defined as locators in this sub-inventory. As discussed in my earlier post, you may choose to define locators using a Row, Rack and Bin criteria and assign a check digit for improving inventory accuracy. An excel spread sheet that makes it easier can be downloaded here. If the pick area stores a particular pack configuration e.g. cases, cartons, units, each, etc. you may also configure the pick unit of measure for the sub-inventory corresponding to this pack configuration. The pick unit of measure will let you configure pick rules that minimize material handling in your warehouse by fulfilling orders in integer multiples of pack configuration.
Dedicated and Floating Locators
Next step is to assign items to your pick face sub-inventory. Here you have two options. You can either dedicate specific locators to items or have a "floating" locator for the item in the sub-inventory i.e. assign items to sub-inventory without assigning a specific locator. As we discussed in the earlier post, you will likely dedicate your best locators to items with high pick frequency and uniform demand pattern.
Replenishment Setup
A pick face needs to be replenished from a reserve or a bulk storage area. The parameters for replenishment such as minimum quantity, maximum quantity and replenishment lot size can also be setup for items in the pick face. The replenishment lot size should be the UOM multiple of the higher level pack configuration e.g. if you replenish 2 full cases every time you replenish the pick face and each full case contains 24 EA, your replenishment lot size is 48 EA.
Replenishment Planning
The first two steps take care of the setup needed for the pick face. In order to keep the items stocked in the pick face, it needs to be replenished at regular intervals. To do so, a min-max replenishment planning can be scheduled to run at regular interval say every 30 minutes. Replenishment planning will compute the replenishment quantity using the following equation:
Replenishment Quantity = Maximum Quantity + Pending Demand - Stock on hand - Pending Supply
Once the replenishment quantity is computed, the replenishment move orders are generated using replenishment lot size. The replenishment move orders that are generated at this point, do not have a source and destination locators identified. Pick and putaway rules let you do that.
Pick and Putaway Rules
Pick rule identifies the source locator for replenishment while putaway rules can be configured to identify the destination locator for replenishment. Putaway rule can be very easily used to select a destination locator that is dedicated to a particular item.
What about floating locators? This too can be achieved using putaway rules. If the item already exists in the pick face, a simple putaway rule can be configured to aggregate material at the same location. You can also use locator flex fields and SQL expression in the putaway rule to setup almost any business policy. The Rules Engine Example (Note: 232247.1) document available on Metalink has sample setup and putaway rules example where locators can be assigned to items based on their ABC classification.
Replenishment Tasks
The pick and putaway rules are invoked during move order allocation. The allocation process also generates replenishment tasks that can be assigned to a warehouse resource for execution. The allocation process itself can either be carried out manually for a move order or allocated in batch using "Move Order Pick Slip report". The replenishment tasks can be dispatched to an eligible warehouse resource as any other pick tasks.
This concludes the 3-part series on stocking policy for your pick face. I will be very interested in knowing your thoughts, any specific challenges that you face or your own perspective on this topic.
Comments (3)
Aditya,
Have you ever come across the situation whereby the customer is using standard carton sizes for all products but does not strictly control the UOM multiples in each carton e.g. one carton might have 50 units in it, another 55? And if so how do you manage the requirement to replenish the pick face in whole cartons?
Posted by David Petronzio | July 3, 2007 9:26 AM
Posted on July 3, 2007 09:26
David
I have come across this type of situation. Though a non-standard pallet is a more common scenario.
If this is the case, you can't effectively model the case as a UOM. There are three alternatives:
a. Vendor compliance: If you have sufficient bargaining power with your vendor, try to enforce UOM compliance i.e. you will accept a case of 50 EA only. In order to make it easier for the vendor, its a good idea to place a purchase order in multiples of integer case quantities e.g. 50 EA, 100 EA, 150 EA, etc.
b. Define Cases as LPNs: You can have each case defined as LPNs and then define pick rules to allocate entire LPNs. However keep in mind that case level LPNs could be messy to deal with especially if you are dealing with a high volume item.
c. Overpick: Define UOM conversion for standard conversion. WMS will create picks for standard quantity e.g. 50 EA. If the operator does encounter a case of 55 EA, an overpick for 55 can be done. However it implies that operator should manually check the quantity in each case. Not a good thing from a productivity viewpoint.
Hope it gives you some ideas
-Aditya
Posted by Aditya Agarkar | July 9, 2007 7:35 PM
Posted on July 9, 2007 19:35
I have similar issue for Replenishment, but form one subinventory to other. The problems are not all LPNs have the same number of products, and we want to move complete LPNs.
How I could tell to rule, only move entire LPN.
Example.
Min 5 Max 50
LPN 55
When I ran the Min-Max, the move order is generated for 50, and in the task asks to pick only 50 not for 55.
Posted by Erwin Cortes | May 22, 2008 5:45 PM
Posted on May 22, 2008 17:45