lunes, julio 14, 2008

Just In Time Production

Dudo mucho que esto sea un tema a tratar en una cervecería virtual como esta, pero nunca se sabe. El caso es que últimamente me estoy topando con el Just In Time por todas partes, y pensé que quizás alguno de los otros miembros de esta ilustre mesa pueda estar al tanto y no le importe leer un poco más sobre el tema.

Lo que sigue a continuación es un texto en el que describo las ventajas y desventajas que aporta esta filosofía de producción importada de Japón (de Toyota, en concreto), en comparación con los métodos de fabricación tradicionales aplicados en Europa y América.

Es triste descubrir que esta filosofía que en Asia emplean desde hace décadas, y que en el Oeste se pagan millones a consultoras que sean capaces de implantarla en cualquier empresa, consista básicamente en aplicar el sentido común a todas y cada una de las tareas que se realizan. That's life. Por cierto una pequeña pega, el texto está en inglés.



For many years now, Japanese companies and their manufacturing methods have impressed western companies. The huge increase in their productivity and quality figures after the Second World War brought everyone’s attention. One of the most successful companies (if not the most) is Toyota, and so, their methods have been “copied” in Europe and US many times, with more successful results sometimes than others.

One of the most characteristics in the Toyota managing method, is the Just-In-Time production, based on the very simple principle of “erasing wastes (anything unnecessary)” from the manufacturing process.

Rather than a method, JIT procedures are more a philosophy, and if we study it in deepness, we will find out that there are no complicated mathematical models or simulations and no complex statistical data behind it, it is all about doing things simple and easy. It requires mainly the focus on two aspects:

* “Pull” system: The production at one level only happens when the upper level has requested it. “Push” methods work the other way round, the line is concentrated “On what’s coming from behind” and so, a global perspective of the line is lost.
* Workers must be empowered to take decisions and eliminate the founded waste, since they are the ones who know the production line better; they ultimately control quality.


Advantages


Because it is a very different manufacturing model from the standard ones in Europe, it has many advantages:

* Inventory: Using a “Pull” method radically reduces the inventory because there are no intermediate stocks. It requires a Kanban system in order to properly track the product during the line.
* Capacity: There is less spare capacity in the line, thanks to “lean” effect produced on it by the pulling system.
* Lead-time: It is obviously reduced given the inventory reduction.
* High Quality: It MUST be Higher, given the fact that each piece clear identified in the line and therefore, each defect is quickly detected.

All these advantages should help to achieve the key aim’s of this philosophy stated in the six zeros:

* Zero Inventories
* Zero intervals
* Zero defects
* Zero breakdowns
* Zero waste
* Zero papers


Disadvantages

Of course, as anything else, JIT systems have some drawbacks that although they can easily be overcame, they must be taken into account very seriously:

* Fragile line: Since there are no stocks between workcenters, the relationship with the suppliers needs to be very close. Any disruption in the chain may cause a stop in the production line, and with no stocks we will suffer any problem that may occur to the supplier:

o Weather problems
o Labour/union problems
o Regulatory changes
o Breaking down due to local government problems:

+ Road repair
+ Municipal services
+ Electricity, garbage removal, recycling

The action needed in order to get over these issues is to have a very close relationship with the supplier, or better say suppliers, because having more than one will help us avoiding those problems. Anyway, what is really needed is a complete understanding of this philosophy by the supplier: if they do not adopt JIT, at least they need to know how it works.

* Variations in demand: Working with such a close relationship with the demand, may be difficult when this demand changes dramatically. In this case, the flexibility of the manufacturing process is basic if we want to adapt in time to the new times.
* Idle Time: The continuous flow has a key problem: all the operations must be done in the same time; otherwise, idle times may arise of machines and workers. The proposed action to avoid this problem is to do a balance of the working times. If we study the operating times of each workcenters and worker, it will be possible to match those differences.
* Throughput Rate: Given again the fact that we will be working with a continuous flow and with no stocks, any setup that needs to be done on a certain point of the line may cause the whole line to stop. Then again, flexibility and control come to our minds. These two features are crucial in order to plan properly these setups and to coordinate them so that no time is lost. Otherwise, the throughput rate will decrease and the idle time will increase.
* “Eastern philosophy”: "The first issue (and possibly the source of all the other problems) is that the entire JIT philosophy is based on eastern cultural characteristics. As with other management innovations which have emerged from Japan, it is reasonable to anticipate that there will be significant implementation impediments when these concepts are applied to western businesses."

This time, probably the only solution available is to take JIT seriously. Everybody on the organisation has to understand how it works as well as the suppliers. It is essential that everyone involved cooperates with the system; otherwise the problems will overcome the line.

3 comentarios:

Morvader dijo...

A costa de ir en contra de todos nuestros valores chigreros, aunque solo sea por esta vez, voy quitame l paliyu la boca y falar de aquellu que conozco.

La primera vez que vi juntas las letras JIT fue en la asignatura de Procesadores de Lenguaje, cuando nos explicaron la compilación just-in-time, que básicamente se trata de una técnica para mejorar el rendimiento de una aplicación compilando/interpretando en tiempo real sólo las partes de la misma que necesitas.
La mayoría de las plataformas modernas (.NET y Java) funcionan así, "pre-compilando" el código para luego ser ejecutado por una máquina virtual que optimiza su comportamiento.

Y otro concepto muy similar al que explicas en el post es la "extreme programming", que ya de por sí tiene nombre de peli de Spilberg y acojona un poco.
Se trata de un enfoque de ingeniería del software para producir programas de la manera más ágil posible, haciendo un desarrollo totalmente adaptativo a las necesidades actuales. En este tipo de desarrollo las reuniones son constantes y más que con informes o documentación se trabaja sobre las actas de reunión.

Supongo que este tipo de técnicas de producción Just in Time serán tanto más útiles cuánto más indecisos y heterogéneos sean los clientes.En mi opinión, para un producto rígido e inequívocamente especificado no tiene mucho sentido. Digo yo...

Eso sí, puxa asturies, cagon rosss !!!!

srcocodrilo dijo...

uoooo!!! Acaba de invertirse la lógica de este blog. Obtener una respuesta a este post es el equivalente virtual a que el dr. alergia haga una rotonda según las flechas del disco... algo inverosímil!!!

Pijadas aparte, JIT es una filosofía y no un método de trabajo, con lo que en teoría ha de poder aplicarse a cualquier proceso, incluidos los informáticos. Llevando esto al extremo, uno podría gestionar su casa aplicando métodos JIT y de Lean Manufacturing con el objetivo de tener todo ordenado y en su sitio, pero eso sería el primer paso de camino a convertirse en un stalker de los buenos.

Resumiendo mucho esta filosofía, se podría enunciar como "el intento de depurar cualquier proceso mediante la eliminación de despilfarros, y a través de una mejor continua."

Creo que esta definición encajaría tan bien en una planta de coches como en un programa informático.

dr.alergia dijo...

chaval, la única manera de llegar Just-In-Time con el twingo es que la última salida de la rotonda sea la primera.