Just-in-time production philosophy

Introduction

Leading companies around the world have adopted this new management philosophy, leading to extraordinary advances in terms of quality, agility in deliveries and costs.

Competitive advantage

We can list five variables that will serve as the basis for achieving this competitive advantage: cost, quality, service, flexibility and innovation. This set of decisions constitutes what is called a production strategy.

The just-in-time philosophy (JIT)

The JIT method is not just another project to eliminate waste or waste.

The Just-in-Time system has four essential objectives which are:

Attack fundamental problems. Eliminate waste. Seek simplicity. Design systems to identify problems.

Attack fundamental problems.

Establish systems to identify problems.

With JIT, any system that identifies problems is considered beneficial and any Establish mechanisms to identify problems.

1. Be willing to accept a short-term reduction in efficiency in order to gain a long-term advantage.

The objectives of Just-in-Time are usually summarized in the so-called "Theory of the Five Zeros", being these:

Zero time to market Zero product defects Zero time loss Zero working paper Zero stock

To which is usually added a sixth "Zero":

Zero accidents.

Cost / benefit of applying Just-in-Time

With the JIT application, all the expenses involved are mainly training expenses.

Just-in-Time is synonymous with simplicity, efficiency, and minimal waste.

Complete analysis of non-productive costs

Current capacity = work + loss

The preliminary step for the application of the just-in-time production system is to fully identify non-productive costs such as:

Non-productive costs due to excess production Non-productive costs in workers' time (unemployed) Non-productive costs for transport Non-productive costs of the processing itself Non-productive costs of stock available (inventories) Non-productive costs for other activities Non-productive costs in the manufacture of defective products.

By eliminating these unproductive costs we can completely improve operating performance by a wide margin. The just-in-time production system clearly reveals an excess of labor. The definition of waste that Western companies have assumed is about "anything other than the absolute minimum resources of material, machines and labor force required to add value to the product." Considering as absolute minimum resources:

A single provider, if it has enough capacity. No people, equipment or space dedicated to repeating a job already done. No safety stock. No excessive lead time. No one performing a task that does not add value.

"Only those activities that physically change products add value." In other words, counting, moving or even inspecting are tasks that do not add value, but cost; therefore they are wasteful.

Operational advantages provided by a strong reduction in stock and terms

Increased agility, and better monitoring of the market.

Ability to meet urgent orders Quick reaction due to shorter lead times Better response to market expectations Possibility of planning production in the short term taking into account only firm orders (instead of planning based on forecasts).

Improved productivity and reduced production costs.

Reduction of warehouses for finished, expensive and rigid products. Suspension of tasks related to the management, handling, transport, surveillance and protection of warehouses (risks of fire, theft, corrosion, etc.).

Space Gain

Reduction of rents or the possibility of using the surface gained for other activities. Possibility of optimizing the implementation of the activities. Elimination of the need to occupy other buildings later on by extension of the activity.

Improving efficiency

Greater visibility. Decrease in the number of information to be taken into account. Better circulation of information. Reduction in the number of missing pieces. Reduction of waste.

Decreased investment needs and relative maintenance burdens:

To the extension of the premises. To the warehouse handling equipment: forklifts, containers, pallets, bridge cranes, among others. To the storage equipment (traditional or automatic). To the warehouse management computer system.

Reduction of routes

Complexity is not inevitable, making it possible to considerably improve the distribution of activities in factories. The cell layout of the workshops.

The geographical separation and the bringing into line of the manufacturing of different products. The other activities to be located next to each other. The decentralization of the activities of reception, storage and dispatch.

Machine cells

A cell corresponds to the minimum route that a piece treated by each of its machines would have to carry out. It allows to chain the successive operations related to the same piece, with which the deadlines are made minimum. Parts are easily located.

Activity groupings

Not all factories can be "targeted" by products and put online. You should immediately chain your operations and remove the intermediate warehouses.

Quick tool change

In the factories, the machines are most often multipurpose, which enables a high utilization rate to be obtained, guarantees their profitability and low production costs. To go from one type of production to another, you have to change the “tool” of the machine.

The idea of reducing tool change times is therefore not traditional in the industry. A sharp reduction in tool change times, however, would offer multiple advantages. A few very simple ideas are enough: changing all fastening systems for instant locking systems, reducing the number of screws and bolts, creating tool sets permanently located light next to the machine, installation of a stock of tools next to the machine, tools transported by a truck dedicated to the machine, review of the sequence of operations, creation of setting gauges, among many other changes. A program to reduce tool change times widely is a competitive imperative for all industrial societies.

SMED application. It is made up of four stages:

Know the real conditions of the preparation to improve. Preparation times are analyzed and identified using the stopwatch. Separate internal preparation from external preparation. It is about separating the tasks according to their nature into internal or external, and performing the external tasks while the machine is working. In this way, reductions of between 30 to 50 percent of the time spent in internal preparation can be obtained. Convert internal preparation into external preparation. This stage is divided into two phases: in the first phase, it is a matter of re-evaluating the procedures declared as internal and, without making any changes to the processes, seeing if there is the possibility of carrying out one with the machine running, that is, making it external. In the second phase,It is done in conjunction with the first, working with processes that are intrinsically internal, looking for ways to make them external by making the necessary modifications. Perfecting all aspects of the preparation. Although with the three previous stages it is possible to have reached less than ten minutes, not for this reason we have to stop and settle for what has been achieved but, as the Japanese have already accustomed us, we will continue reducing the preparation time, both internal and external.For this reason, we must not stop and settle for what has been achieved, but, as the Japanese have already accustomed us, we will continue to reduce the preparation time, both internally and externally.For this reason, we must not stop and settle for what has been achieved, but, as the Japanese have already accustomed us, we will continue to reduce the preparation time, both internally and externally.

Usual enhancements for quick tool change

Avoid travel, waiting, waste of time, search, need to choose. Have everything you need next to the machine. This is achieved by: tool sets, gauge gauges, setting instruments, next to the machine; materialize areas for classified placement of tools in lockers. Dedicate means of maintenance. Suppress physical efforts. This is obtained thanks to: tool trolleys at machine height; devices to place the tool (bearings, slides); pneumatic or hydraulic jacks for lifting tools; and revision of the tool design to avoid having to disassemble more than a small part of the tool.Reduce tool fixing times. Reduce the number of bolts and screws; reduce the length of the bolts and screws;replace holes with notches and notches (to avoid having to completely unscrew the bolts Reduce adjustment and connection times. By normalizing tool heights, shims, color markings, graduations, notches; adjustment templates; presence, next to the machine, of a type tasting witness piece to be produced. Carry out tasks after hours. Cleaning, maintenance, sharpening of tools; cleaning, control and contrast of gauges; preheating of tools; and partial disassembly of the tool previous.Review the conception.Normalization of the pieces to be produced; and normalization of the dimensions of tools and molds.By standardizing tool heights, shims, color cues, graduations, notches; adjustment templates; presence, next to the machine, of a type tasting witness piece to be produced. Perform tasks after hours. Cleaning, maintenance, sharpening of tools; cleaning, control and contrast of gauges; preheated tools; and partial disassembly of the previous tool. Check the conception. Standardization of the pieces to produce; and standardization of the dimensions of tools and molds.By standardizing tool heights, shims, color cues, graduations, notches; adjustment templates; presence, next to the machine, of a type tasting witness piece to be produced. Perform tasks after hours. Cleaning, maintenance, sharpening of tools; cleaning, control and contrast of gauges; preheated tools; and partial disassembly of the previous tool. Check the conception. Standardization of the pieces to produce; and standardization of the dimensions of tools and molds.preheated tools; and partial disassembly of the previous tool. Check the conception. Standardization of the pieces to produce; and standardization of the dimensions of tools and molds.preheated tools; and partial disassembly of the previous tool. Check the conception. Standardization of the pieces to produce; and standardization of the dimensions of tools and molds.

Suppression of random risks

Numerous random risks can disrupt the production and operation of traditional factories, such as missing parts, delays in shipping from suppliers, frequent machine breakdowns, quality defects in manufactured products. Safety margins here take the form of high stocks and long terms, which are accompanied by disorder, unproductiveness and sharp increases in costs.

The reliability of the machines

This lack of availability severely cuts the production capacity of the machines and thereby increases the average cost of production. The lack of availability of the equipment is the result of two phenomena: lack of reliability and insufficient maintenance. Lack of reliability explains the high frequency of failures and incidents. Defective maintenance results in long repair and set-up times.

The breakdowns and incidents in the operation of the machines can present multiple aspects. An industrial machine is a complicated system, made up of mechanical, hydraulic, electrical and electronic elements. The possibilities of breakdowns or incidents are therefore multiple.

It should be noted that these inadequacies of the machines rarely require their replacement by newer equipment. The design of the machines may also be responsible for some repairs, since the elements are difficult to access, not very modular or requiring too much time for their replacement.

Since production is the raison d'être of factories, machines are intended to be used to the greatest extent possible. It is therefore difficult to find time for maintenance. This lack of cleanliness has detrimental effects on the reliability of the machines. The layer of dirt that covers a machine prevents seeing an oil leak, which foreshadows a further breakdown.

The correct thing is to implement preventive and predictive maintenance. Preventive maintenance consists of systematically carrying out interventions, essentially to change elements and leave the machines in good condition again.

The set of such actions can be grouped under the term "Total Productive Maintenance", of which preventive and predictive maintenance represent only two aspects.

The actions to be carried out are inspired by three simple ideas:

In order to reduce the number of machine failures, it is first of all necessary to know what is happening to you. To improve the use and monitoring of the machine, you must involve your operator. Given the multiple cases of machine breakdowns or incidents, you can seem difficult to quickly reduce its frequency. It is really enough to be logical: you have to start fighting the main problems.

Thus improving the safety of men and machines (Zero Accidents). Focus primarily on the most frequent problems. After a single week of implementation of the notebooks or monitoring software, it is easy to identify the two or three types of breakdowns or incidents that immobilize the machine most frequently. In this way, those breakdowns that generate greater problems in the regular operation of machines and equipment are attacked. It will then be necessary to proceed with the improvement of the machine. Incident due to misuse of the machine. Incident due to lack of current maintenance or cleaning. The operator must be in charge of the cleaning and current maintenance of the machine or equipment. Incident due to normal wear and tear, caused by the operation of the machine.

The problem of reliability cannot be reduced to the treatment of serious breakdowns through preventive maintenance.

Cleaning of each machine by its operator.

Improvement of the machines.Improvement of the conditions of use.Training of the operators.Conservation carried out by the operators.Preventive maintenance.Predictive maintenance.Maintenance from the conception of the machine or equipment, by improving its reliability and ease of use. maintenance.

For this purpose, a diagram of Total Productive Maintenance (TPM) is given below.

Total Productive Maintenance

Something vital to improve quality, as well as to reduce inventories and reduce idle times for both machines and personnel, is to install Short Preparation Times (SMED) systems and Total Productive Maintenance.

Total Productive Maintenance is an approach to equipment maintenance that results in no shutdown.

The quality of production

Producing a defective part that must be discarded in the middle of the production process represents, on the one hand, the loss of the investment made in the part until the defect has arisen, but also causes us to manufacture another part to replace it and continue the process. productive, so the total cost of the defective part is, on the one hand, the part itself plus the costs of replacing it.

The four levels of quality management

Different levels at which the quality management system can be framed can be detected in the various companies, depending both on the development of the existing quality system and on the focus in each of them.

Level 1: Inspection. At this level it is assumed that the company produces quality defects and there is a team or department that is solely and exclusively dedicated to separating the products. However highly developed the inspection may be, if this is the only tool used to obtain quality products, We will be at the low level of quality systems. In the most evolved quality systems there is also inspection, but the philosophy is totally different. It is not a matter of inspecting to eliminate defective products, but to compare the quality obtained with the planned quality, study the deviations and correct the process to obtain the desired quality. More ambitious quality systems like Six Sigma don't even accept the possibility of defective products.In these systems, the final inspection can be eliminated by replacing it with process inspections. If the process is controlled, the final quality will be as planned.

Level 2: Quality Control. The application of statistical techniques to production processes allows us to obtain very valuable information about production processes. We can determine the capacity of a process, that is, demonstrate whether the process is well enough prepared to produce without quality defects under normal conditions.

Level 3: Quality Assurance. Quality assurance is one more step in the evolution of quality systems because in these systems all departments of the company are involved, not only the quality department, greater importance is given to the human factor in the company and the management The company begins to take the leadership role in achieving quality objectives. However, quality assurance systems are not the most evolved quality systems known because they have a certain quality objective and they are limited to ensuring that level of quality without worrying about exceeding it. Although continuous improvement is encouraged in the better-known quality assurance systems such as ISO 9000 and others, these systems are not sufficiently evolved to achieve permanent process improvements.

Level 4: Total Quality. Total quality integrates all the quality elements of the previous levels but extends them to all levels of the company and all its personnel. It is at this level that the companies that have implemented the Just-in-Time System operate.

Currently companies with quality systems of different levels coexist in the competitive arena, despite the increase in competition and the globalization of markets are inexorably pushing companies to develop more evolved quality systems.

The basic pillars of any quality system

The pillars on which all effective quality systems must be based on columns are:

The conviction of the Management. The training of managers and staff. The Statistical Process Control. And, the Continuous Improvement.

Management conviction. The conviction of the Management is fundamental and indispensable for the purposes of building the Total Quality System. Quality systems are based on very long-term improvement strategies, or elements that are difficult to assess in the short term.

Companies with a Just-in-Time system must choose the most beneficial long-term alternative

Training. Another of the pillars on which quality systems are based is training. In the words of the Japanese consultant Ishikawa “quality begins and ends with training. Quality systems seek to take advantage of all the capabilities of the company's employees, but not only the capabilities already demonstrated, but also the potential ones. Two aspects must be highlighted when we refer to the concept of training in quality systems.

Statistical Process Control And Continuous Improvement

The entire quality system must seek a single objective: to organize the activities of the company and create the appropriate management structure to allow continuous improvement.

Relationship with suppliers

The uncertain quality of the delivered products. The quality requirements expressed by the company to its suppliers are in the nature of good wishes without being accompanied by any demand for proof of quality control of the products delivered.

A large number of suppliers and antagonistic relationships. For this reason, the company has thousands of names in its supplier file. The company cannot hope to rival its international competitors if it maintains antagonistic relationships with suppliers that deliver its orders infrequently, long terms and without quality assurance. Today it is crucial to destroy the barriers that separate the company from its customers and suppliers.

The participation of suppliers in the design stage of the company's products and services is of fundamental importance.

The kanban

Kanban is considered as a subsystem of the Just-in-Time system. In the system in question each process

What is a Kanban?

A Kanban is a tool to achieve "Just-in-Time" production. Two main types are used: the transport kanban and the production kanban. The first specifies the type and quantity of product to be removed by the subsequent process, while the production kanban indicates the type and quantity to be manufactured by the previous process, and is therefore called a process kanban.

Author's conclusions

The Just-in-Time system forms a broader system called Kaizen, a system that pursuing continuous improvement allows for a systematic and sustainable reduction of both cost and failure levels, while increasing productivity and customer satisfaction levels.

Trial Comments

The Just In Time production methodology aims at continuous processing, without production interruptions. In the just-in-time application, production times are considerably reduced, since when producing in small batches, defective parts are easily detected in each of the departments that enter the production process, thus carrying out a control that allows any time modify the process that is causing the deviation.

The work that adds value to the production, is the one that during the processing on the materials and components represents one more aggregate of the final product.

Just-in-time benefits

Investments decrease to maintain inventory. Inventory turnover increases Material losses are reduced. Improve overall productivity. Lower financial costs Savings in production costs Less storage space.Quality problems are avoided, bottleneck. coordination problems, unreliable suppliers, etc. Rationalization of production costs. Obtaining little waste. Effective knowledge of deviations. Decision making at the right time. Each operation produces only what is necessary to satisfy demand. There are no random or disordered processes.The components involved in production arrive at the time of use.

Just-in-time application environment

The Just in Time methodology as a productive management and management procedure can be used in any type of company, both industrial and services.

Thematic annex

The philosophy that frames just-in-time production is to produce only the necessary quantities of product and when required by customers.

Just in time vs. Traditional production

The main differences that arise from the Just in Time model and the traditional production methodology are summarized below:

Decrease in inventories

The Just in Time system seeks to reduce inventories to very low levels, while in the traditional system, materials are supplied and transferred to the next process regardless of the level of existing demand.

In traditional production, products are moved from one group of identical machines to another department with machines that perform other specific work, the Just in Time replaces this pattern with one of production cells in which the machines are grouped into families and they are arranged in such a way that a series of sequential operations can be carried out.

We leave you with the next couple of videos through which you can learn more about the just-in-time production philosophy and its advantages, as well as the main elements that make it up. The first video (12 minutes) is a theoretical approach to the system and the second (23 minutes) is a documentary that shows how JIT has been applied in a British car producer. Good material to complement and deepen your learning.