Standards are one of the cornerstones of modern manufacturing. However, they are not easy to write, and a bad standard can make things even worse than before. In my previous post I started to introduce how to write a standard. This post continues the topic of writing a standard with a few more tips.
Christoph Roser
Standards Part 3: How to Write a Standard
Standards are the result of problem solving. In this article I will talk more about how to write a standard, but this is the outcome or the last steps of the problem-solving process. From this post onward I will look more at work standards, although the following is applicable to a lesser extent to part standards. Again, a standard is not something done on its own, but is part of a problem-solving process.
Standards Part 2: Why and Where to Do Standards
Standards are crucial to making your manufacturing system work smoothly. But where should you have standards? Sometimes you hear the answer, “Everywhere,” but this is not really helpful and I also think not really correct, either. Hence, let me talk a bit on why and where to have standards. This applies to all kinds of standards, not just the standardized work that is the most widely discussed one when talking about standards in lean.
Standards Part 1: What Are Standards?
Standards. You know they are important for manufacturing. You know Toyota and hence lean uses them extensively. But you may also know that they are not easy. I was thinking about writing a few blog posts on standards for a long time, but… it is a challenging topic. Let me give you my thoughts on standards and how to use them in lean manufacturing. But before going deeper into the use of standards over a few blog posts, I’ll provide a quick introduction on standards.
How Much to Adjust the Pull Inventory Limit
In my last post I looked at the behavior of the supermarket inventory for different kanban systems. In this post I will use this information to estimate how much the material availability of a system changes if you increase or decrease the inventory limit of your pull system (i.e., number of kanban).
Parts of this blog post are loosely based on chapter 13.2 of my new book All About Pull Production: Designing, Implementing, and Maintaining Kanban, CONWIP, and other Pull Systems in Lean Production.
Behavior of a Kanban Supermarket
Setting up a kanban system is tricky, especially determining the number of kanban. The kanban formula is at best a rough estimate. It is usually advisable to adjust the number of kanban as the system is running. In general, if you have too much inventory, reduce the number of kanban. If you run out of material – and the cause is a lack of kanban – then increase the number of kanban. However, this general recommendation can be refined a bit by looking at the supermarket inventory. Let me show you how to improve your kanban system by analyzing your supermarket inventory.
This blog post is loosely based on chapter 13.2 of my new book All About Pull Production: Designing, Implementing, and Maintaining Kanban, CONWIP, and other Pull Systems in Lean Production.
Performance Comparison of Job Shop and Flow Shop
Job shops are, in their nature, much more chaotic than flow shops. Previously, I have written a lot on this topic. In this post I would like to take a deeper and quantitative look at this effect. Using simulations, we take two systems and try to make them as identical as possible – except that one is a flow shop and the other is a job shop. This blog post is based on a thesis by my student Daniel Ballach.
What Different Pull Systems Can Be Combined?
In my last few posts I have shown you different ways to establish pull systems, and which one is right for you. This post discusses how you can mix and combine these systems. You can combine some pull systems within the same pull loop, although there are some restrictions. Combinations of different kanban systems are very common, often also including a CONWIP system.
You can also combine different pull systems for sequential loop, where for example a kanban system feeds into a CONWIP system. This blog post is loosely based on chapter 3.3 and 11.1.7 of my new book All About Pull Production: Designing, Implementing, and Maintaining Kanban, CONWIP, and other Pull Systems in Lean Production.
This is a cross post with the same article on Planet Lean.