Written for all people interested in the subject, but primarily for people working with manufacturing execution.
Queues (-or waiting lines) in every shade is a strange phenomenon.
Whether we are stuck in our car at the motorway, the checkout counter in the supermarket, checking in for a flight, waiting rooms etc. Every time we encounter a queue, we ask ourselves the questions: For how long am I supposed to wait here? For how long am I supposed to be in this queue, and when will the queue possibly dissolve itself. These are some of the questions we ask ourselves many times in many different situations each day. And often there are no answers.
The traffic light
We must put this into a system structure to be able to deal rationally with the phenomenon. There are 3 queue phases at a servicing facility: Being served right now (analog to a green traffic signal), Waiting in a queue to be served (analog to a yellow traffic signal) and Arriving at some later point (analog to a red traffic signal) at a possible queue.
An example: 8 check-out counters are open in the supermarket. You are checking out right now at one of them (Green status = Being served). Other customers are queuing up at the checkout desks ready to be served (Yellow status = Queuing). And others customers are still filling their cart (Red status = Arriving later because they must queue up to pass the checkout desk to get out again)
The short history of queue management
Originally it was a Danish engineer guy named A. K. Erlang in the early 1900 who put his thoughts and experiences down on mathematical formulas in his work designing and dimensioning a telephone exchange central based on old mechanical relay technology and the expected traffic. A real technical queuing problem to secure everyone would get telephone connected without too much delay. Erlang’s work became the basis of queue management theories.
There is a lot of mathematical formulas behind all this stuff in the dimensioning of queue systems.
I will save you from all this and come to a point where it is possible to manage your own queues; for example if you work with planning and execution in a manufacturing production.
The NAVEKSA SHOPFLOOR planning and execution solution
At NAVEKSA we have built a SHOPFLOOR solution for Microsoft Dynamics NAV which operates on easy-to-understand queue principles. We have replaced the check-out desks with work centers, operators, machines and resources, and as production orders move through the factory executing enforced different processes at different “check-out desks” – cutting, turning, drilling, welding, assembly etc. they will be handled on an individual basis by their status at each “desk”
All people understand these “traffic-light” principles because they have their roots in what we all are exposed to and understand in practice every day.
On top of the moving status system we have added information and decision points to solve problems related to managing inappropriate queues in terms of the opportunity to adjust servicing resources, re-sequencing and re-prioritizations to make the most out of a certain resource.
And that is why our customers are successful using our solution.
No fancy algorithms, just pure common “traffic light “sense for all involved people.
The key to manufacturing execution success
It is a well-known fact that the key to successful manufacturing operations are managing the right sequence and avoiding bottle-necks in a clever way. This has huge influence on all kinds of inventory levels and customer service. And to this right you need the right tools. I simply do not believe the macho-people types who think they can manage a complex production from a piece of scratch paper or an excel sheet in an optimal way. They cannot. Soon they will leave with a lot of stress.
So the task is to go from chaos and firefighting to well-ordered execution:
All production people must pull together
As a last point please remember there is just one success criteria when using an IT manufacturing planning and execution system: ALL involved people (planners, shop floor operators etc.) must understand and must be able to operate the system. This includes also the person out back in the far corner in the factory not having a PC at home, a smartphone or other IT-competencies. If not, your solution or ambitions are deemed to failure.
Thanks you very much for reading ! Bent Korsgaard, MD at NAVEKSA