Process/line/workload balancing

In every company, no matter how well intentioned managers are, there is a high chance that some people have more work to do than others. Some processes are more work intensive than others. Some production lines are more technically complex than others. While it is impossible to try and balance out every single workload (for one of my projects I’ve tried to do it to the best of my abilities, and still managed to only get within +/- 10% of each other) it is a good measure to at least try and use resources equally and thus increase flexibility by not overworking some and underworking others

Line (or process or workload) balancing reduces variations within a production line by making it more stable and flexible enough to adapt to unexpected variations. For example, let’s imagine we have 3 production lines that make the exact same product. One line outputs 100 pieces an hour, the second outputs 300 pieces and hour and the last outputs 500 pieces an hour. It is clear that the 3 lines aren’t balanced, and this lack of balancing causes ripple effects in production, both for the production teams, where some are working 5 times faster than others as well as for supporting functions like logistics, where there is an uneven delivery rate of raw and finished materials, making things complicated for those who follow up on it. 

So what balancing does is try to make sure that all production lines run more or less on the same speed, making it easier for everyone to follow up. If we do line balancing correctly we end up with a situation where we reduce a lot of wastes, like waiting and inventory.

Let’s imagine the 3 lines from the previous examples as making 3 different types of products, that have to be sent together to the customer. The line that outputs 500 pieces an hour will end up having 5 times as much inventory and waiting time compared to the line that outputs 100 pieces. We end up with a situation where we have to wait on line 1 before we can send out the product bundle to the customer. That is pure inefficiency.

 The way that line balancing happens can be varied.

We could do time analyses of the activities that take place in the lines and try to see which tasks take longer on one line than another, and then fix the root cause

We could identify technical bottlenecks or excess capacity. Are the machines on line 1 older than those on line 3? Do we really need to output 500 pieces an hour or is that just a competition between the line managers?

We could reallocate resources. We see workers on line 1 are all new recruits that don’t understand the process. We can move a few experienced workers from line 3 to line 1.

We could improve other things. There isn’t enough light on line 1 so it’s impossible to focus as well as needed to produce the pieces. We implement standard lighting all throughout the production hall and suddenly line 1 produces more pieces.

Ideally, we would do all of these steps, as we want to have the most balanced and most efficient line working possible, but since time and resources are probably always going to be limited, then we need to apply the ones with the highest chance of success in the current environment.