As we celebrate the start of 2023, it’s interesting to reflect on how technology and innovation have changed the shop floor.
We generally have more technology innovation than ever, but new challenges are evolving at an equivalent pace:
We’re not telling you anything new of course. For Operations, dealing with these challenges is daily life. Still, it’s relevant because within this new reality, line philosophy needs to be perfect and most often, it can be overlooked.
In a typical accumulation packaging line, a so-called V-Curve is most often used to set the production line speed.
What is a V-Curve? Is there a ‘better way’ to set line speed?
Today we’ll dive into the V-Curve theory and analysis, the pros and cons of this set-up and, most importantly, a dynamic alternative to production line speed control.
Accumulation production lines rely on this structure to manufacturing line optimisation running states. The V-Curve set-up is relatively straightforward:
1. Start by identifying the slowest machine on your line. This will be the critical machine.
2. Then, set the standard running speed for all machines according to the critical machine speed (in normal conditions).
3. Next up: Set the two machines immediately before and after the critical machine to 10% faster in recovery speed (this is after a buildback scenario downstream, and after a lack scenario upstream of the critical machine).
4. After these two are configured, adjust each machine after/before them to run faster by 10% increments in recovery speed.
5. On top of all of this, machines will use sensors on the infeed and outfeed to intelligently identify lack or buildback.
Picture this setup as a 'V'. The critical machine may be a filler. The one after it, a labeller. The piece of equipment before the filler might be a depalletiser.
Here's a shot of what a V-Curve might look like in a typical production line.
Advantages of the V-Curve theory:
Disadvantages of the V-Curve theory:
While the traditional V-Curve method is a proven approach, communication between PLCs and other technology advances allow for more precise and dynamic line control.
Dynamic accumulation allows for additional empty conveyor space, lending operations a bigger buffer zone in the case of stoppages or breakdowns.
While in these instances the critical machine is the only one that will be running at a consistent speed, all other equipment can handle lack and buildback.
Getting the V-Curve right:
Identify the real critical machine:
Your production line can be optimally balanced