A recent article from CIOInsight made light of the fact that many customers report that their ERP system are underutilized (note not specifically SAP). I will not get into a discussion on whether this is important or not but I do bring it up because as I work on SAP systems and I do have the opportunity to see that in many cases functionality which can have a large impact on productivity is either incorrectly used or not used at all. We recently worked on a study to identify the best ways SAP customers can optimize their logistics execution processes and this bit of functionality came up.

Anyone using SAP WM can have a big impact on efficiency and productivity by you probably already guessed it implementing queues. Yes your probably saying, ha Phil we use them here. Well before you get all smug, let me say that in my experience and I have been working SAP WM systems ( and non-SAP) for some time, most implementations are either not using them, using them improperly or in a very limited fashion. Now after making a bold statement like that let me add the following caveat, any system is only good if it supports your business and there certainly maybe a very good reason for using functionality in some way other then intended.

Why do I want queues?

If I told I could give you real-time visibility to your workload in the warehouse and also visibility to your workers wouldn’t that be great, and to add icing on the cake increased your workers utilization/productivity, ok I have your interest don’t I. Read on and I’ll show you an example of how this works.

Hopefully your somewhat familiar with WM concepts so this will make sense. (you can see some of my previous posts on this subject i.e. The IM vs. WM series )

What is a queue?

First before I get into my example, let’s start with what SAP says about queues

You hurt your what?

Ok, let me put it in my words, queues are a logical representation of your work areas that include work tasks and resources.

Queues are defined using standard SAP configuration tools so this is not something you’ll be able to change on the fly.

One way that queues can be used is to establish queues that correlate to you functional work areas in your DC or plant. Your specific requirements will define your model so this is just for my example. In my example I have queues for Picking, packing, Replenishments, receiving putaways etc. Easy enough.

Our example queues

Ok, now that we have established some queues let’s see how they are used and why they are so important.  Note queues are based on transfer orders, why is this important? Well if you noticed in my design I do not have a queue for inventory control, this is because unfortunately inventory documents are not tracked in queues, a lost opportunity if you ask me, but I digress.

Each time a transfer order is created SAP assigns it to a queue. If you look at a typical transfer order you will see the queue assignment in the header as shown in the below example. If your not using queues yet it will be blank.

Transfer order header detail

Workload visibility

Ok now let me introduce you to the tool used to manage your queues, this is the Warehouse RF monitor (T-code LRF1 and LRF2) this is a central display of all transfer orders active in the warehouse and guess what they are grouped by queue, ok I am sure you are now starting to see the picture. In a typical distribution center It might be that you can have 100’s or 1000’s of open TO’s at any given time but without the RF monitor (the name is part of the reason why some clients have been lead to believe it is only useful in an RF environment. It should be labeled something else really) there is not an easy way to visually see your workload. This is really the only central tool that visually displays where and what I have to work on in my warehouse from your own meaningful perspective. Now before you get all excited it does have it’s limitations so it’s not a complete warehouse dashboard, the main limitation is that it is transfer order dependent as I mentioned above. (I’ll talk about the warehouse activity monitor in a later post but it’s not exactly a complete tool either).

Warehouse RF monitor

Resource visibility

Ok as shown above now all the open TO’s in my warehouse are nicely divided up by the queue (functional area) so I can see how many active transfer orders I have in my warehouse at any point in time, Nice!! But I’m not done (ok I’m starting to sound like a infomercial) This is where an RF enabled warehouse leverages the use of queues. SAP has developed functionality for use within RF based applications (we leverage it in our own library ) to allow you to assign your workers to queues, now if you didn’t use any other functionality at this point you can still use the RF monitor to see how many open TO’s you have within a queue and I also can see who is currently actively working in that queue (think of it as an area). Sweet!!

Worker visible in a queue

In the above example I can see that I (PAVELAR) am currently working on the receiving area doing putaways. See how useful this can be?

OK, so we are almost are done, I have queues, I have transfer orders in my queues , and lastly I have my workers assigned to a specific queue, now the Pièce de résistance , SAP and my company of course have developed system guided RF applications, this simple explanation is that the SAP system uses the queues to assign work to your resources (yup SAP actually assigns them the work) , I think your probably starting to see the possibilities.

Ok let me walk you through an example of how this works. Lets say I have a picking queue (and no you can’t have mine get your own ) and I have open transfer orders in the queue to be picked. When a worker accesses a system guided application, the application goes to the queue the resource is currently assigned to and selects the next open transfer order to be worked on and assigns it to the worker. It does the same for any other worker that accesses the application. When a worker has completes a transfer order the application assigns the next available transfer order from the queue and keeps going until there are no more or the worker logs off, which ever comes first. No fuss no muss, just productivity baby!!

Ok so that helped your productivity but there’s more…. (I think I missed my calling)

Let’s go back to our handy RF monitor and let’s see what’s happening.

If you look at the RF monitor you will see it is broken up into 3 sections, the main section is the queue display which we looked at earlier but let’s take a closer look.

Warehouse RF monitor

This has a break down of the queues we defined but also look at the columns to the right, I have a Column “TOs” for the number of open TO’s available, “Last” which is your calculated workload and the last 2 columns are what I like, the Proc. By (huh?) is how many workers are currently logged into a particular queue, the column with the traffic light is a visual indicator that based on a ratio you define (not as complex as it may seem) means that I either have too many workers in a queue based on the proportions of workers to queues or I have too many TO’s and not enough workers. I know at this point your sold right?

Ok there is one last piece I want to mention here and that is drag and drop, yes I know sometimes there are employees you would like to drag and drop and now you can. Ok it’s not what you think but if you highlight a worker and drag them from one queue to another in essence you have reassigned that worker to start to get assignments for the new queue. Certainly in some cases this makes absolutely no sense but if you have a extensive structure then it might make sense to move a worker on a forklift from high bay picking to replenishments, this would make sense and the only impact after you have dragged and dropped the poor worker is that the next transfer order he is assigned directs him to replenish a bin as opposed to taking the goods to the shipping dock. You didn’t even move out of your chair. Seriously though this dynamic reallocation of resources is important and a key element in fully utilizing your labor and of course deploying them to the most critical areas of your operations.

Although I was pretty thorough there is still more functionality available but I think you get the idea.

Summary

Lets summarize why you want to use queues

• Enables an inexpensive Warehouse dashboard to view real-time workload (at least transfer orders in your DC), got to start somewhere.
• Enables system guided functionality for use in driving resources in the warehouse, and makes them more productive.
• Provides a management tool for repurposing associates to address bottlenecks in real-time in your DC.
• Because I said so. ok maybe not.

Well that’s it for todays post, I hope I was able to shed some light on this topic, if you have any questions always happy to hear your comments. 

Later…