An Overview Of Poka Yoke And Quality Control Strategies

It is important that you pay close attention to the quality of your products. Businesses that produce poor quality products are rarely successful. There are several reasons for this. In the worst case scenarios, dangerously defective products could be produced.

These reasons could lead to recalls or even a lawsuit. However, there are other situations where the lack of quality assurance could result in cumulative losses over the course of time and is just as damaging to your business.

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How Quality Control Can Help Your Company:

Incorporating quality assurance into your business's manufacturing can make your workers' tasks less repetitive and will decrease employee burnout at your business, and it will increase your business' productivity and worker satisfaction. When employees are more satisfied with their jobs, they will be more easily able to learn new information that can further streamline production. Also, the increased workplace satisfaction can decrease the amount of employee turnover and can save your company a significant sum of money.

Saving the money and effort is better to be put into recruiting new hires.The increase in internet usage over recent years also makes quality assurance especially important for your company. If the quality of your products is poor, wrong information can spread quickly online and can be true even if only a small number of your products are defective or of poor quality. In fact, only a few negative articles on the first page of results for a search of your business could cause your sales to decrease by as much as 70%! A single negative article on the first page of results for a search of your business could lead to more than a 20% decrease in sales! These types of losses have the potential to ruin your business.

Increased in returns are due to products that aren't of high quality. Product returns cause unexpected losses. Returns can occur even if a product isn't defective but merely of mediocre quality. Putting quality controls in place at your company can ensure that returns occur less often.

An organized effort for managing quality can reduce the amount of time and effort that goes into training your workers. If there are relatively reliable methods in place for ensuring the quality of products, the burden of quality assurance won't be as strong for as many of your workers as it would be otherwise.

If errors do somehow slip through the cracks, they will be spotted right away if methods of quality assurance are in place and will ensure that the errors do not occur over an extended period. Without adequate methods of quality assurance, errors can go undetected for a long time and could result in many customers receiving a faulty product!

The Affordability Of Quality Assurance:

In many cases, implementing quality assurance is quite affordable. In fact, devices that would make a part of the manufacturing process run with nearly no risk of error are available for less than 100 dollars. A minuscule cost to pay considering what these devices can do for your company. Also, the common quality control device for your production could save you more than 2,500 dollars per device, according to one company! This average was obtained from the results of quality assurance devices at a well-known telecommunications company. The specific cost to savings ratio for your business may vary, but it is likely to be highly advantageous to your bottom line.

Paying close attention to the quality of products is an integral part of a well known Japanese business philosophy. A famous Japanese business expert named Dr. Shingo started the theory in the 1960s. In Japanese manufacturing, quality controls are referred to as poka-yoke. This strategy can be incorporated into just about any lean manufacturing process.



There are different ways that poka-yoke can be implemented into your company. For some companies, the operator of the company is immediately alerted if errors in the process are detected. Dr. Shingo called this method a 'warning poka-yoke'. In other cases, the process isn't completed if an error has been detected. This was referred to by Dr. Shingo as 'control poka-yoke'. Here are a few ways to integrate poka-yoke into your company's manufacturing process:

The Motion Step Method:

The motion step method ensures that the correct manufacturing process was followed. If the process was not correctly followed, the operator is alerted, or the production of the product is stopped before it is sold. This method does not necessarily involve direct examination of your final product. However, it can be a highly effective poka-yoke method for the production of certain items.

The Fixed Value Method:

This poka-yoke method involves a check to ensure that the right number of steps were completed. If an additional step is performed or a step is omitted, this method will detect it immediately. This method can be essentially a fail-safe method of quality assurance for some companies. If it is appropriate for your company, this method might be somewhat easier to implement than other methods of quality screening.

One example of the fixed value method in action would be a drug company selling cold medicine in single dose sized containers to prevent a customer accidentally taking too much of the medicine. Another example would be an operator of a bottling plant using a container that holds six bottles and checking to see that the containers have all the bottles. If you choose to implement this poka-yoke method, you will have to decide how it will work best for your company.

Using The Contact Method:

The contact method is another common poka-yoke strategy . When this method is used, the final product's physical attributes are tested. This helps to detect and prevent defects in the product. There are different ways that the contact method can be implemented. In some cases, an employee or group of employees can check to ensure the quality of a product. In other cases, the contact method can be implemented through machinery.One example of the contact method in action would be ensuring that a USB drive can only be plugged into the correct ports and checking to see that it fits. Assuming a product was checked at the factory according to the pre-determined manufacturing process, the product could never be sold if it was faulty.

Poka-Yoke Example

Poka-Yoke Example

Tips To Ensure That A Poka-Yoke Strategy Is Effective:

  • The manufacturing process must always remain the same, and the end product should continue to be the same. If there are any changes to the production process, you must develop a new strategy.
  • It must be known exactly what the final product is supposed to look like, before starting production. While this may seem obvious, small errors in the process often go undetected due to an operator being unaware of what individual errors would look like. This is particularly true about complex manufacturing processes, such as manufacturing for the electronics industry.
  • The poka-yoke must be included at the right point in the process. In other words, it must be included in a cause and effect. For instance, a poka-yoke device would be ideally positioned after a product goes through an assembly line but before it is being sent out for shipping. The errors must be caught while they can still be easily corrected.
  • A poka-yoke device should be utilized whenever different steps could be followed next. For instance, if a car factory needs to paint cars with a particular set of features in a specified color, it would be wise for the company to install a poka-yoke device before the start of the painting process. You can also apply to parts of the assembly process when replacement parts are necessary, or manual processes must take place at certain intervals.
  • It is a wise idea for you to put a poka-yoke device in any area part of the manufacturing process where an error is likely to occur and includes areas where parts are configured similarly to one another. In these cases, machines may be better able to detect errors than the human eye.

How Much Effort Is Needed To Pay For Poka-Yoke Strategies?

The amount of time, money and effort that you need to dedicate to quality assurance depends on the product you are making. If you are operating in an industry that requires the manufacturing of products with exceptional precision, it is necessary to put a significant amount of effort into quality control. If you are making a product that has a relatively simple manufacturing process, less effort might successfully ensure that your product remains produced to a high standard of quality. You will need to make a detailed assessment of your product before determining what poka-yoke methods to put in place.

Author: Eric Raio

Eric Raio is one of the founders of Factory Solutions. When he isn't plotting new ways to create awesome software. He likes to geek out about flying drones and technology.

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