The Impact of Batch Size on Flow | Operational Excellence Quick Hits
Quick Hits share weekly tips and techniques on topics related to Operational Excellence. This week’s theme relates to Organizational Performance Part 7: Batch Sizing Decisions. We hope you enjoy the information presented!
Speaker 1: (00:05)
In today’s session, we’re going to talk about understanding flow and the impact of batch size on flow. So if you remember, from our previous sessions, we talked about what flow looks like and value added activities, activities that transform the product or service one step closer to what the customer’s demanding and then value added activities, which don’t transform. If we look at a timeline, what poor flow looks like as we have very few times where we have value added, but the non-value added time when you keep time waiting time while the product or service is waiting to be worked on is significant, much larger than the value added time. We want to look at improving flow and cutting down on the non-value added time, not focusing on the value added time. One of the things that really affects our flow is batching. So batching is defined as the amount of work that is done before switching off to do something else. So a lot of people try to be efficient by batching work.
Speaker 1: (01:16)
What are different batching definitions? So the order size is typically what the customer orders under one purchase order that you’re going to process within your organization. The batch size is the number of items that are released under one work order that might be released to someone in the system to start working on. We can also look at transfer batch. So transfer batches amount of work that is transferred from one operation to the next operation within the same run or within the same setup. And then we have a process batch, which is the amount of work for this process as a group between runs. So that means we have to do some changeover or some activity to change from one process to another process as part of that Batch. What’s the impact of Batch reduction on the organization. So if we look at Batch and Queue Processing, and this can be any type of product, any type of service, or even meetings as a form of batching.
Speaker 1: (02:23)
We don’t make decisions until meetings. So what happens is a lot of information gets batched. So in this case, we have three process steps and there’s 10 items that need to be processed through process A. Then 10 have to go through process B and the same time 10 need to go through process C. So we process all of items, one through 10 on process A, it takes one minute to process each unit. So in that case, it takes us 10 minutes to get through process A, it gets moved to process B same thing, one minute to complete those. So 10 minutes on process B, and then we move that to process C, were same thing one minute for the 10 items. So the total time to complete the whole order is 30 minutes that’s without any setup time between processes.
Speaker 1: (03:16)
Then our first piece comes off. After 21 minutes, we got 10 minutes on A, 10 minutes on B, and then the first good piece comes off after one minute on process C, after 21 minutes, where if we look at Synchronous Flow and we can go from process [inaudible 00:03:33] A to process B to process C, we can look at first minute, we start minute two we’re parallel processing, minute three we’re parallel processing. So our first good piece comes off after three minutes and the total order takes 12 minutes. So we’re cutting the lead time from 30 minutes down to 12 minutes.
Speaker 1: (03:54)
So of course, process batch will increase setup, but transfer batch, we’re doing, we’re just transferring components from one step to the next step. It doesn’t affect setup time. It affects transportation time. So if we have long distances between operations and we do Transfer Batch Reduction, we’re going to increase our transportation time. Otherwise, if we do Process Batch Reduction we are going to effect set up time, so then we would look at different techniques to solve those problems within the organization, but either way Transfer Batch, Process Batch Reduction can significantly improve flow and lead time. Remember most operations in the process have excess capacity. If, you’re an unbalanced operation. So doing more setups on a process, that’s not a bottleneck or a constraint doesn’t hurt the system. It actually helps the system.