Kanban systems are a huge help in industry, ensuring a steady availability of parts and products without excess stock. However, Kanbans are not necessarily limited to industrial use. In this post I will describe a simple Kanban system for office supplies. This system is also sometimes known as triangle kanban. One benefit of this system is that it will improve the availability of pens, paper, and other supplies. However, a second major benefit is that this provides a risk-free opportunity to train your people in creating and using Kanban systems.
Simple Kanban System for Office Supplies
The principle of restocking office supplies is similar to restocking industrial parts and products. At one point you order more, and some time later the products will arrive. It also has the same problems as with industrial parts. When you find out that you are out of stock is usually when you need the goods. Hence, taking control of the information and material flow can help. However, while you can establish a full-blown system with Kanban cards on all packages, defined rules for supermarkets, calculate the number of Kanban, establish lot sizes, and many other details, this feels overdone to merely order pens.
Hence, simplicity is the key. Usually, office supplies are rather inexpensive. Hence, while minimizing inventory is usually a big deal in industry, the effort is usually not worthwhile to save a few pens. The bigger problem is running out of pens. Let me explain to you my method using my most favorite Uni-ball Jetstream Retractable Roller Ball Pens as an example. Here’s what I do:
I have a number of boxes of pens in the office supply cabinet. Only the last box has a colored laminated Kanban card attached. On this card it says:
If you open this box, put the card on the assistant's desk. Assistant: Re-order three boxes Uni Ball Jetstream Pens in Blue, Number xyzabc.
As a result, whenever we are down to the last box, the assistant is informed to reorder more pens. The assistant collects this and other cards and, once per week, orders office supplies. When the supplies arrive, the assistant sticks the card on the last box using adhesive tape, and the cycle can start again. Since all people in the office are informed about this system, it has worked flawlessly for me for many years.
In industry such single kanban systems are also known as triangle kanban, since the kanban is often triangular shape. The number of parts after the triangle kanban has to cover the time until the system is able to restock the inventory (the replenishment time).
Examples of Products for Simple Kanban Loops
There are many different examples for products that can be managed using such a simple system. One major category is office supplies. Pens, papers, scissors, staples, markers, etc. can all be managed using such a system to avoid stock-outs. In truth, a stock-out in pens is usually not critical. People generally have multiple pens, and if the blue one is out then they just take a black one. Of course, it is a problem if pens are missing, but compared to other problems on the shop floor these are minor.
Much more serious is another stock-out in the office: Coffee! Many office workers seem to be unable to work without this stuff. And, for some reason, substituting tap water doesn’t help. However, you can use the same simple system for coffee supplies. The last box of milk has a card, as does the last pack of coffee beans, sugar, and so on. Since I’ve been using this system, I’ve never had a stock-out on coffee, which probably would have much more serious consequences than a stock out on pens :-).
Yet a third instance where I use this system is for printer ink at home. I have multiple packages of ink in different colors. The last one has a Post-it attached, telling me to reorder magenta, blue, yellow, or black. Again, if your printer strikes due to low ink, it is usually a most inconvenient time. Luckily, with using this system, it has not happened so far.
Benefits of this Simple System
The system is actually quite simple. The last box has to be enough supplies to last until new supplies have arrived. If you have a larger office, you may add the Kanban to the second to last box.
The colored card with the instructions is usually self-explanatory. Even people new to the office have no problem using this system. Usually, I have multiple boxes in the system before the Kanban. In theory, only one box would be needed to cover the replenishment time. Having multiple boxes, however, allows for a less frequent reordering, saving time for the assistant. The time to order one box is the same as for ordering three boxes. Due to the (usually) low value of the goods, the time saved is worth the extra stock.
This is especially true when ordering printer ink at my home. I usually order a year’s worth of supply, so that I have to go through the hassle of ordering and picking up ink parcels only once per year rather than every month. Overall, the system is very little effort for small and low value goods, yet ensures good availability of material.
A Great Training Opportunity
I cherish this method also for a second reason: It is an excellent example to teach your people Kanban. The system is very easy to understand, very visual, and requires no fancy computer support. Yet it contains all the important elements of information and material flow. Both supply and demand can have fluctuation that have to be covered. Information and material flow is standardized. The replenishment time can be estimated to see how many boxes you would need.
Most importantly, this is much more than a theoretical class room exercise, but a real-life working system with which your people interact on a daily basis. Hence, there is usually much more motivation to do it right. I hope this post was helpful for you.
Now go out and Organize your Industry!