When was six sigma developed

This article will explain how Cpk is calculated and interpreted. We will explore its application, benefits and provide some tips and best practices so that you can begin assessing how well your process is doing when measured against the requirements specified by your customer. The goal of process capability is to come up with a quantified measure that informs you as to whether you are meeting your customer expectations or not as well as a relative value of how well you are meeting or how badly you are missing.

It represents the best the process capability can be for the specs and process distribution. If there is only a one-sided spec, then Cp cannot be calculated. Therefore, if we look at the formula above, a value of 1 would mean that the width of the distribution is equal to the width of the specifications or specs.

A value greater than 1 would mean that the specs are wider than the distribution of the process, so we are comfortably within spec. If the value is less than 1, it means that the width of the process distribution is wider than the specs, and items will be outside the specs.

But this is rarely the situation. Since the process mean is now off center, you will report out the minimum condition depending on whether the process has shifted closer to the upper spec or closer to the lower spec.

Essentially what you are doing is measuring the distance from the mean to the different specs. Then you divide that distance by half the width of the distribution or 3 standard deviations. See the formula below. A value greater than positive 1 means that the spec limit is far enough away that the process should be capable and be within specs. A value of 0 means that the mean of the distribution sits on the spec so that half the process will be out of spec.

This means the closest spec is 4 standard deviations away from the mean. If staying in spec is critical, then the preferred value is 1. Finally, if the value of Cpk is 2, then the closest spec is 6 standard deviations.

But, as it is in most cases, if the process is shifted off center, then the Cpk will account for that shift. If a manufacturing line had a Cpk of 0. The owner, Norman, was an advocate of Lean Six Sigma and had improved their processes as well as invested in the best equipment available. He was sure that his competitors were nowhere as good. Using the Cpk formula he backed into how much tighter the specs could be made and still be well within them.

Knowing his competitors, Norman figured that if the specs were made tighter, his competitors would no longer be able to produce products at a competitive price or quality. That meant Norman would get a bigger share of the total business. He realized that he did not need to stay centered within the specs. Therefore, he adjusted his equipment to produce off center and closer to the lower spec while still staying well within spec.

This allowed him to reduce the amount of plastic in each part, therefore saving a small amount of money on each part. Since he was producing parts in the millions, the small increment of savings would add up to a significant increase in profits.

A win-win all the way around. Cpk is a generic measure of how well a department is doing relative to its required specs. You can also calculate Cp, Pp and Ppk to measure process capability. It assumes that the process data is normally distributed but does not require that the mean of the process be centered if there are upper and lower specifications.

That difference is then divided by 3 standard deviations. The higher the value is, the better the process capability. It can be used for any process with stated specs or qualitative expectations and can be used as a comparative tool across different functional areas.

Instead, they wanted to measure the defects per million opportunities. Motorola developed this new standard and created the methodology and needed cultural change associated with it. Since then, tens of thousands of companies around the world have adopted Six Sigma as a way of doing business. Six Sigma is a top-down solution to help organizations:. The Six Sigma Management System drives clarity around the business strategy and the metrics that most reflect success with that strategy.

It provides the framework to prioritize resources for projects that will improve the metrics, and it leverages leaders who will manage the efforts for rapid, sustainable, and improved business results. Enthusiasm for Six Sigma, in all its manifestations, has been building in the United States since the s. Today, almost every corporation in the world uses Six Sigma or some form of quality management system.

Six Sigma, although originally a method of production process improvement, has since been applied to many processes unrelated to manufacturing. As noted by Motorola, "Transactional processes -- such as billing, customer support, etc. While Six Sigma is an admirable standard to aspire to, some companies find that it simply costs too much to maintain the standard of Six Sigma, and instead adopt a Five Sigma standard.

Five sigma is DPMO. Improving quality to a point where there are less than DPMO is still a huge accomplishment and may certainly be an acceptable standard, particularly in those sectors that do not impact consumer health or welfare.

Renee O'Farrell is a freelance writer providing valuable tips and advice for people looking for ways to save money, as well as information on how to create, re-purpose and reinvent everyday items. Her articles offer money-saving tips and valuable insight on typically confusing topics. O'Farrell is a member of the National Press Club and holds advanced degrees in business, financial management, psychology and sociology.

Who Started Six Sigma? By Renee O'Farrell. What Is 'Systems Thinking' in Business? As noted above, individuals can obtain Six Sigma certification, which solidifies and verifies their professional skills. These certifications are awarded through a belt system similar to karate training. These belt levels are:. People with a black belt can become masters and champions. Someone with a master black belt is considered an expert and strong leader with excellent problem-solving skills.

A champion is a lean Six Sigma leader who can maximize profits through the elimination of waste and defects. You can get certified by going through courses offered by certain schools or companies. Keep in mind, though, that there is no unified standard for the courses. As such, the curriculum for Six Sigma certification varies, which means individual courses can vary depending on the offering entity. Six Sigma is used by corporations and local governments. Below are two examples of how six sigma improved operational efficiency, saved money, and increased customer satisfaction.

Microsoft MSFT is one of the largest software producers in the world. In order to improve the reliability and availability of its networks worldwide, Microsoft implemented Six Sigma methodologies to use a robust data-driven process to help eradicate any defects in their systems and data centers to systematically reduce IT infrastructure failures. The company first established standards for all of its hardware and software to create a baseline measurement for detecting defects.

Microsoft used root-cause analysis, including collecting data from past high-priority incidents, server failures, and recommendations from product group members and customers. Using the historical data, Microsoft established baseline standards from which to measure going forward.

Large amounts of data were collected on a daily and weekly basis from various servers. Data analysis and reporting identified the defects and remediation steps for each defect were then established.

The incidents were prioritized based on how severe the defects impacted the business and the company's underlying services. Using Six Sigma methodologies, the teams executed eradication initiatives of the defects. The mean or average time between server failures improved from 18 days to days. As a result of Six Sigma, Microsoft improved the availability of its servers, boosted customer productivity , and increased customer satisfaction.

The local government began to use the program on a county-wide level in and has trained more than 5, employees on employing the methodology. The county states the savings are coming from hard budget items, which no longer need funding as well as savings in employee hours. You can get your Six Sigma certification through a company or college. Keep in mind, though, that there is no unifying body that standardizes the curriculum.

This means that courses can vary based on where you take your course. Six Sigma refers to a methodology that is driven by data and statistics. It is used by businesses to eliminate defects and improve any of their processes in order to boost their profits. Six Sigma is a process with a certain outcome. Companies implement Six Sigma to help eliminate defects and improve processes so they can boost their profits.

Companies that put lean Six Sigma methods into their plans do so in order to improve performance by eliminating waste and defects while boosting the standardization of work. The key with lean Six Sigma is to add value for the customer. This is an acronym that stands for define, measure, analyze, improve, and control.

Go Lean Six Sigma. Accessed Oct. Purdue University. Six Sigma Daily. Career Advice. Business Essentials. Business Leaders.