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Total quality techniques for continuous improvement

Table of contents:

Anonim

COURSE AGENDA "BASIC QUALITY CONTROL"

OBJECTIVE: This course aims to delineate the basic concepts of quality that any worker in a company must handle, from the heads to the lower level personnel, both in the productive area and in administrative and sales areas. Knowing techniques for identifying and solving problems, types of inspection and mainly knowing what your responsibility is in the quality of a finished product and in the degree of customer satisfaction, regardless of your position in the organization.

INTRODUCTION

In today's competitive world of companies, we must ensure that the process is aimed at improving the level of customer satisfaction as a result of our activities.

For this to happen, the entire organization's commitment in time and effort is required, in understanding what is happening within the company, why it is happening in this or that way and what is the role that each of us must play to cause improvements in systems.

Within our work we can cause great progress by doing our work with quality, which ultimately translates into quality products and that is what the customer expects from us.

We observe day by day that technological advances in the field of processing and control in companies are rapidly increasing, but for companies far from large world centers such as our country, it is very difficult to obtain these technological advances quickly and even within our There are companies with more or less resources in the country.

But we can supply a large part of these advances and finally we come to compete to some degree with these companies, replacing high technology with greater performance, efficiency and increasingly exceeding our quality of manufacture and service.

It may be far from being the most advanced company in the area, but it is up to us exclusively when we want it to be the best.

THE MEANING OF QUALITY

In our daily life the word "quality" is closely linked to us and although everyone talks about it and insist that they have quality in their articles, likewise when they buy an appliance for their home they demand quality, we like to dress in quality clothes, eat good quality food, in short, we live surrounded by that magic word called quality and we demand it, but ultimately, do we really know what quality means?

Defining the word quality is something very broad, there would be as many definitions as there are people in a classroom, perhaps one of the most technical as a definition is the following:

"Quality is the degree of adaptation of a product to the needs of a user".

This in other words means giving the customer what they want, when they need it, and at a fair price, it is giving them a good reason to buy our products again.

Quality is ultimately, not only the intrinsic quality of the product, it is also the speed and the way to satisfy customer needs, deliver orders correctly, invoice correctly and a wide response from our after-sales services.

We must also supply products and services at a cost that the client is willing to pay and to achieve this objective we must minimize the number of errors and corrections that we may have in our production and administrative processes.

QUALITY CIRCUIT

In the definition of Quality it was mentioned that it was "the degree of adaptation of a product to the needs of the user". This means that each article that is manufactured responds and must therefore be in accordance with a need, which forces us to ask ourselves the following questions before creating a product:

  • What we want to produce. What is the objective. How we are going to produce it.

This leads us to create a series of stages for the manufacture of a product, which are called "Quality Circuit" and is established as follows

According to this scheme, the "Quality Circuit" is composed of the following steps:

  1. A market that has a need for the product to be produced. Set the objectives. The "what" is required to produce. Establish a program for the elaboration of the product, which establishes the stages of production and control. Design the product with its standards and specifications. Begin with its production with the proper personnel and machinery for the elaboration of a good quality product at a reasonable cost Establish a distribution network suitable for the market that can be by sellers, representatives, distributors, as well as direct sales to the public or all at the same time Have a support and service network technical according to the market.After completing these stages, we are just in the presence of a product made capable of satisfying the demands and demands of the market.

COST / QUALITY RATIO

At one stage of the Quality circuit, the phrase "good quality and reasonable cost" was mentioned.

We know that when manufacturing a product it will have a manufacturing cost, it includes raw materials, energy consumption, supplies, payment to personnel, maintenance and in general all the expenses that originate in the production of the product and its environment.

We also know that these items will have a price in the market that must be in line with the competition of similar products and also with the quality that it has during its use.

To achieve good quality and a fair price, manufacturing costs have to be within a reasonable margin and within these costs are those assigned to quality control, which must maintain a balance between the cost of quality and the intrinsic value of the quality.

To better understand this balance, we will now look at what is known as “Jurassic Schemes”, in which firstly what is the optimal manufacturing quality, then what is the minimum cost to maintain quality.

Optimal quality is considered the right balance between quality cost and quality value.

Analyzing table 1 we can see that even if we increase our quality costs, whether by incorporating a new technology, more personnel for control and more qualified (therefore more expensive), a point is reached where the value of the quality of a product remains stationary and higher quality is not achieved no matter how much we control. Therefore, you have to find a middle point between the quality you want to obtain and the expense involved in achieving it.

In Table 2 we see as more costs are incorporated into quality control, losses due to defective items can be reduced, but it reaches a point that it is more expensive to control quality than the benefits it brings. Let's not forget that these costs are included in the final price of the article and there may come a time that it is so expensive, even if it is of the best quality, that we will not have a market that is willing to acquire it and our work will not make sense.

For this reason, all companies and sometimes international organizations give quality guidelines, setting specifications with minimum and maximum ranges of defective items or quantity of defects per unit.

The best way to solve this problem is to have the right and qualified personnel to control quality and in the productive area to have highly specialized workers at each stage of the process, with a clear awareness of what it is to work with quality, capable of self-controlling their own work and correct the deficiencies that occur in the process, just for the fact of being better and wanting to do your job better.

We must not forget that the quality of a product is not obtained by the one who controls, it is manufactured together with the product and is made by the worker who works directly in the process.

INCORPORATE QUALITY INTO THE PRODUCTION PROCESS

The issue of maintaining quality in the production process is, in general, in a nebula of desires, ideas, criteria, consumer demands, similar items from the competition, etc.

The personnel involved in product quality is also very diverse and their interests are consequently very diverse. Sales, acquisitions, design, the availability of money for the acquisition of inputs, raw materials and materials intervenes in this matter has a strong influence on quality. The production areas must be limited and adjusted to all of them and their work has a direct impact on the final quality of the product. Even with all these limitations, the Operations Management must deliver a finished product that satisfies the Sales Management, who appreciate it for the customer's response, at a cost within the margins established by the General Management, solving the problems generated by the lack coherence between what is required and what is provided by the different links in this chain.

Although the General Management is responsible for the decisions that affect quality, we have to worry a lot about how it is going to be controlled. One of the most important requirements is to establish clear quality policies and they must be in writing.

There are many advantages to a written quality policy, first it demands thought, second it is a means of communication, especially in relation to authority, third it outlines the primary objectives of the control program and finally it creates an exchange of information through which management You can determine the degree to which quality policies are being met.

When the quality objectives are in writing. they become significant and have a great tendency to unify criteria, also promote harmony, motivate action and allow planning of operations.

WHAT IS TOTAL QUALITY?

We have seen and analyzed what quality is within a productive company and it is necessary to have a basic idea of ​​what total quality means as such, we will do this based on the following definition:

“TOTAL QUALITY is the set of efforts deployed by the different means of an organization, which are integrated for the development, maintenance and improvement of the quality of a product, in order to make possible manufacturing and service to the complete satisfaction of the consumer and the customer. most economical level ”.

As you can see, this definition speaks of the different levels of an organization, it does not refer specifically to a group, be it inspectors, analyzers, nor to specific areas. It refers to each of the components of the company, because just like safety, quality is a responsibility of each member of our organization from the General Management to the most modest worker.

Total Quality is based mainly on standards, specifications and ethical principles that regulate the manufacturing process to achieve a good final quality at a minimum cost, avoiding unnecessary losses. This stage is called "Standardization" and we will define by rule "any specification that has turned out to be good over time." In short, they are the requirements that a product must have to be of good quality.

Total Quality is the incorporation of quality into the supplies, processes and completion of the articles to be manufactured. Controlling quality in our various operations involves inspections during the arrival of supplies, during the process and at the end of the production line. It also implies the obligatory establishment of norms and quality standards and the standardization of procedures with respect to constancy in the determination of our quality requirements.

So, in order to obtain quality control, we must control the output quality of products at each point of our manufacturing processes.

When we define our quality requirements, which are the accepted products and which are rejected (reprocessed, classified in second quality or discarded) and we establish a written registration procedure, indicating the number of pieces or lots accepted, rejected or discarded, we are in the presence of the first step to a quality control program.

Although the log only provides us with a history, it certainly tells us what the level of quality is being produced. The more defined we can make the inspection procedure and the more specifically we can define defects, the greater the interrelation we will have between our inspectors and the more successful we will be in the pre-written standards.

If we subsequently receive complaints or returns from our consumers, we have to redefine our criteria or take corrective or disciplinary actions with those workers who do not meet the pre-established standards. Corrective actions are a fundamental part of quality.

In this way we can have a final inspection, a quality control, a statistical control, the latter consisting of a quality control through the law of exceptions, this control by exception is known as "control by sampling" and depends for its reliability from another law, that of "mathematical probabilities" or the "law of chance."

Instead of inspecting items in process 100% at each stage, we select samples and then based on the data obtained, we will judge these samples taken as representative of the lot or batch. If the sample has a defect or is outside the established specifications, the whole lot will be rejected and 100% inspected, but if the sample yields values ​​within the control limits then the entire batch is accepted and can continue to the next stage of the process..

Inspection, therefore, constitutes the heart or motor center of quality control as a program, that is, when we speak of quality control or statistics we are simply referring to the degree and form of inspection.

While the inspection alone almost always represents only an opinion, the Quality Control and the final inspection formalize it within a pre-written and carefully drafted standardization to support this opinion. Statistical quality control makes this even more precise, by establishing a level of quality measurement using the percentage of defects in the Plant.

Final Inspection is an operation that is performed at the completion of the manufacturing process. Its purpose is to determine if the finished product was made not according to the specifications and the required tolerances, defining whether the product is accepted or rejected. Generally, this inspection is carried out on fait accompli, except for defects that could be reprocessed to eliminate them, but reprocessing increases the cost of the product, which, since it cannot be transferred to the price, makes the item more expensive and the profit obtained from it is less.

When a 100% inspection is made, the client could be sure that the products will be of the required quality, this can offer the company a reputation for good quality in its products, but the result is that it has a higher cost due to the high percentage of rejects or second quality and for executing an operation that alone adds more cost to the product.

Experience indicates that a 100% inspection is not 100% effective and the reason is that the human eye is unable to distinguish good from bad for 8 hours straight. This can be verified in companies that have a 100% final inspection and claims and returns still persist.

In the same way, 100% inspection does not act as an effective corrective action, since the faults found are not all registered and the data is not enough, nor does it go back to the operation that may have caused the failure.

Likewise, inspectors are often given verbal instructions and lack written information to guide or backtrack through a failure. The inspector has to use her own judgment or seek that of the supervisor, who in turn uses her own judgment. Simply put, the entirety of the final inspection is based on one person's skill, efficiency, judgment, and experience.

TYPES OF INSPECTION

In quality control there are two types of inspection to control production processes, these are: Inspection by Attributes and Inspection by Variables. But before knowing these two types of inspection, we will define the concept of inspection.

"Inspection is understood as the set of measurement, verification and testing procedures that aim to compare a product with its specification".

Inspection by attributes is the type of inspection in which each item is simply classified as defective or non-defective, that is, the number of defects per unit is counted, according to a set of specifications.

Variable inspection is the inspection of a unit of measurement in which a specific quality characteristic is measured on a continuous scale, such as kilograms, centimeters, meters per second, etc. and its value is noted.

CLASSIFICATION OF DEFECTS

Critical defect: it is a defect that, according to good judgment and experience, can present dangerous conditions or risks of accidents for users or those who depend on the product, as well as prevent the tactical function of the final article.

Major defect: it is a defect that without being critical can result in a failure or reduce the possibility of the use of the article that is intended.

Minor defect: it does not appreciably reduce the possibility of using an article for the purpose that it is intended or that, when interpreted in relation to the established standards, shows a discordance that does not produce appreciable consequences in the use or operation of the product.

CLASSIFICATION OF DEFECTIVE

Critical Defect - Has one or more critical defects.

Major defective: has one or more major defects but no critical defects.

Minor Defect - Has one or more minor defects but has no critical or major defects.

Product unit: it is the quantity of product inspected to measure its quality characteristics according to its specifications.

Percentage defective: it is obtained by dividing the number of defective units by the total number of units inspected and the result is multiplied by 100

Percent Defective: Number of Defective Units x100

Total number of units

ASSIGNABLE AND NON-ASSIGNABLE CAUSES

Within a production process, failures inevitably occur in the different operations, some due to deficiencies in the handling of materials and / or machinery and others that are not direct causes of these deficiencies. These faults are called "assignable causes" and "non-assignable causes."

Assignable causes: are those that are not produced by chance, and produce large variations in quality results, they can be identified and corrected.

Non-assignable causes: those causes of variation caused by chance are generally inherent to the process and are not identifiable for correction.

PARETO PRINCIPLE

One of the most indicative tools for the causes of rejection and that allow us an objective view of the points to attack in the solution of these rejections is the so-called "Pareto Principle" or as it is also known "80/20 Law".

Pareto, an Italian economist, recognized that most of his country's wealth was in the hands of very few people. About 80% of the money was in 20% of the people.

In many situations, a similar pattern becomes apparent when we consider the relationship between the number of items and their construction to the extent of the problem. This pattern was referred to as the 80/20 law and it is demonstrated in many ways.

For example, in the clothing area of ​​a company, 80% of the failed product corresponds to 20% of the total number of failures recorded in that area. Taking this same example to the sales area of ​​a company, we can determine that 80% of the orders are made by 20% of the customers.

The 80/20 principle does not exactly mean that 80% of the problem is in 20% of the data considered. The figures can be 70/30, 90/10 or even 60/40. The ratio itself is not as important as the fact that it is the main causes that are emphasized.

The Pareto principle should not be used as an isolated tool, it has to be tried to apply in conjunction with the “Cause and Effect Analysis”.

CAUSE AND EFFECT ANALYSIS (fishbone diagram)

The Pareto principle allowed us to find which were the problems with the highest incidence in the quality results, but it did not allow us to obtain a means to solve these problems. This is where cause and effect analysis becomes a proven technical tool to help understand the true causes behind a problem.

Each problem is the effect resulting from a particular cause or a combination of causes. We know the effects but we need to find the cause that originates it.

For example, if a machine does not work it can be for various reasons: electrical failure, mechanical failure, material failure, operator error, etc. We know the effect: the machine does not start, but we must discover the cause, a way to provide a solution to the possible problem.

The causes are represented in a cause and effect or fishbone diagram, as shown in the following figure:

WORKFORCE

MATERIALS

MACHINES

METHODS

PREPARATION FOR THE FISH BONE DIAGRAM

  • Identify the problem to be solved with a Pareto analysis can help to work on the problem Schedule a joint session with the most suitable people who can collaborate with ideas about the problem and its possible causes State the problem as an effect at the end from the fishbone diagram.Add branches to the main spine, each branch represents a particular cause. Most of the situations will be addressed using the four main categories of causes: Machines or equipment, Methods of work, Material and Labor, (las 4 M.) and the diagram remains as stated in the figure above. Discuss the information presented by way of determining the most outstanding causes. A decision on the cause can be made by:
  1. Majority vote Using the Pareto system known data.

Remember to use Pareto associated techniques and sessions with idea collaborators.

Do not narrow down the standard ranking, 4M are often chosen to help you find other preference groupings.

Listen to the causes to solve the problem. Remember that all ideas must be taken into account at the beginning of the work, then the ideas that are closest to the problem are selected.

Use the “Fishbone” diagram in successive steps of a process to extract common causes that help us to solve the problem.

Use the “Fishbone” diagram to focus reasons for making improvements, as well as to find the causes of problems.

Always remember to listen to others, everyone in the organization has ideas and those who are closest to the problems and know the solutions best are the workers who work in the areas where these problems occur. Do not underestimate the capacity of those around you, they are the best support for your management.

Total quality techniques for continuous improvement