Category: Control Charts

You can learn a lot about your process by monitoring its change over time. There are different trend charts which will allow you to do that. Let’s look at a few. 

Background FabChip (fictitious name) was a leader in the global semiconductor industry, known for its cutting-edge wafer-fabrication equipment. With the semiconductor sector at the core of everything from smartphones to medical devices, FabChip’s role in supplying this vital technology was crucial. The equipment FabChip manufactured, however, was often large and complex. When it arrived at […]

Have you ever wondered why your doctor may keep you waiting in the waiting room or why you have to fast before doing a blood test? Let’s see if Lean Six Sigma can give you an answer.

Steps in Constructing an X-Bar and R Control Chart: This document contains the step-by-step instructions to construct an X-bar and R control chart. First the R chart is constructed. If the R chart validates that the process variation is in statistical control, the XBAR chart is constructed.

Do you possess a crystal ball to see what the future brings for your organization? Probably not, but you do have a statistical version of a crystal ball by using trend analysis. 

Are you hearing voices? If it’s in a business context, then there is nothing to worry about — and it might even be a good thing. Let’s listen in to the voice of the process and hear what it has to say.

The run chart is a powerful, simple, and easy-to-use process improvement tool. Often, the run chart is shortchanged as the statistical tests that can be used with run charts are overlooked. This article takes the reader through the benefits of a run chart as well as how to correctly create and analyze one. […]

Steps in Constructing a p-Chart: p Charts can be used when the subgroups are not of equal size. This guide shows you the steps involved in constructing a p Chart.

Out-of-control Action Plans (OCAPS) are a piece of the Lean Six Sigma methodology that is often overlooked. Though they have been phased out in some organizations, it is important to understand their purpose and how they can help a company improve its processes.

Does your data from yesterday represent the current state of your process better than that from a month ago? How can you place more emphasis on it yet still make use of older data? That’s what the Exponentially Weighted Moving Average does. 

Common cause vs. special cause variation, aren’t they the same thing? At first glance, you’d be allowed to think so. However, as with any part of the production cycle, there is a reason for these two measurements to exist. So, let’s dive right into what makes these variations different, and how to identify […]

Throughout any project, you’re going to gather up quite a bit of data. Now, this can be broken down into two categories: variable and attribute data. Understanding the difference and learning how it is applicable during the analysis stage can be crucial for future decision-making. So, with that in mind, let’s take a […]

Control charts have two general uses in an improvement project. Undeniably, the most common application is as a tool to monitor process stability and control. A less common, although some might argue more powerful, use of control charts is as an analysis tool. Throughout this guide, you’ll have the various control charts identified. […]

The seven basic tools in my home tool chest are a hammer, screwdriver, wrench, saw, drill, pliers, and duct tape. What basic QC tools do you have in your continuous improvement tool chest? Let’s check it out.

Short production runs are a necessity in high-mix, low-volume manufacturing environments. The trend in manufacturing has been toward smaller production runs, with production runs – as well as products – tailored to the individual customer’s needs. Although this minimizes inventory and improves responsiveness to the customer, it complicates the application of statistical process control (SPC). Classical […]

Providing the proper organizational environment for engaging people in your continuous improvement effort will provide large benefits for your organization. In this study, we look at how the combination of using control charts and providing an environment for people engagement helped one company achieve significant financial benefits. Control charts are a powerful tool for understanding […]

A box plot may seem like a simple tool, but as this example shows it can help reveal common and special cause variation that may not have otherwise been noticed. Be sure you’re looking below the surface to optimize your performance!

A U chart is one of four quality control charts that engineers use to track variation in a manufacturing process. The other three typical quality control charts are the p chart (which plots the proportion of defective items, the c chart (which shows the number of defects), and the np chart (which shows the number […]

When you speak of subgrouping, it is usually in the context of constructing a control chart. Let’s explore the topic in a little more detail. Subgrouping is a technique used in control charts to group data into smaller, more manageable sets or subgroups. The purpose of subgrouping is to increase the sensitivity of the control […]

Do you want to know whether your process is in control or not? Statistical Process Control, or SPC, is the tool you want to learn about, so let’s get started. 

How do you know if your diet is working? You need to start with a baseline and then measure change from that. You should do the same for all your processes. From that process baseline, you can know whether your process is getting better, worse, or not changing. The term “process baseline” typically refers to […]

In-control is not referring to the behavior of your children. It’s about whether your process is exhibiting common or special cause variation. Let’s explore how this works.

Are all your organization’s problems and issues of equal importance? Probably not. How should you handle those that are the most critical and important? Let’s find out. A Key Business Issue (KBI) refers to a critical problem or challenge that your organization faces, which can significantly impact your performance, growth, or competitiveness. KBIs are specific […]

Since there is variation in all processes, how can you tell whether the variation is due to random expected variation, or something unexpected? The control chart is a tool for making that distinction. Let’s learn how that is done.