Introduction to material flow

Distribution in plant design involves the analysis of the space needs for each center of work, the total available space, logical relations within the productive process and the costs of displacement of materials generated by the distribution. Thus, if the design is not suitable, will appear the lack of optimization of production-related problems of varied origin.

A correct distribution of plant is the base for an organization to achieve its objectives in its supply chain, maximizing plant efficiency and minimizing the cost of operations.

To start the theme, we must give a first definition of the term layout.

Overview

Material flow - Layout is a term use to designate the physical layout of spaces, facilities and jobs. The displacement of people, supplies and products, trying to minimize the costs of storage, handling and transportation. To facilitate information flows and processes input/output products.

Work on the layout represents a valuable aid to gain efficiency and safety. The importance of having a correct distribution of plant is behind an incorrect setting there are lots of hidden costs such as, for example, unnecessary movements of materials, energy expenditure and time, wear additional staff physicist, as well as excessive handling of the materials, which carries risks of suffering blows, cracks and other defects that translates into a waste and require, often, to do the work again.

Between waste to avoid in a company, there are three directly related to the distribution plant and material flow:

• Timeout: occurs when a worker remains stopped waiting to get the material or that the machine runs out of process.


• Transport: are the costs associated with the movements of materials, i.e., resources that are used for these (people, machines, etc.).


• Motion: move, itself, does not add value to the product. For example, a worker can stay hours moving the plant materials. These hours have increased the cost of the product associated with the materials but however do not they added no value.

For this reason a good distribution in plant directly affect the productivity of the same.

The relationship between a good distribution in plant and the improvement of productivity with the following relationship can be summarized as(material flow):

• The production capacity increased: with less cost.


• Decrease in delays in production: balancing of loads and reduction of the storage of material in process.


• Allow greater use of machinery and labor by reducing waiting times.


• Shorten production times by reducing distances, waits and storage.


• Reduction in the requirements for movements of materials.

It is necessary to take into account the factors that directly affect the design of the layout:

• Materials: Design, variety, quantity, necessary operations and their sequence.


• Machinery: Production equipment, useful, tools and their use.


• Labor: direct, indirect, supervision and ancillary services.


• Movements: Transport of materials between operations, storage, inspection, etc.


• Waits: Temporary and permanent storage.


• Services: Maintenance, programming, launch, etc.


• Building: Interior and exterior elements, distribution and equipment installations.


• Changes: Flexibility, versatility and expansion.

We see an interesting presentation that will help us to better understand all these concepts.

There are different types of distribution in plant based on different factors: product distribution, distribution by process, distribution group or cell manufacturing and distribution by fixed position. In the following sub-sections explains briefly what each one of them.

Distribution line of manufacture (product-oriented).

In this type of distribution jobs are prepared in accordance with the sequence of operations that favor the flow of product to the customer. The objective is to minimize the displacement of the product and that the jobs are in the most appropriate sequence this will be fulfilled.

Advantages:

• Low levels of material in process.


• Low investment materials.


• Avoid costs of storage and movement.


• Minimize handling materials.


• Easier production scheduling.


• It reduces the congestion and the area occupied by halls and storage.

Disadvantages:

• It requires greater investment


• They are designed for a specific product, which makes them inflexible.


• Design and implementation to more complex.


• A fault can disrupt the entire process.


• Downtime in some jobs.


• Increasing individual performance has not impact on overall performance.

It is more effective and efficient distribution when justifies it a high volume of production of identical or very similar units. It is necessary that the balance of operations and continuity of materials circulation can be accomplished without many difficulties.

Functional distribution (process-oriented).

Machines are distributed according to the function or process carried out. It is the plant is organized in sections whose machines perform similar operations. Advantages:

• The best use of the machines allows one smaller machine investment.


• Flexibility for changes in products and the volume of demand.


• High incentive for workers to raise their performance.


• There is local accumulation of experience in the process.


• It is easier to maintain continuity in production in case of machine failure, lack of material or part of staff absent.

Disadvantages:

• High levels of inventories of work in process.


• Expensive maintenance.


• Complex programming.


• It requires skilled labor.


• Transport between work centers.

This type of distribution is recommend for a process with a variety of products and demand low or intermittent of each of them. Also if there are wide variations in the times require by the various operations.

Distribution by group or manufacturing cell.

Is a combination between the distribution process-oriented and product-oriented?. It is a plant organize into different sub-sections each of which can operate with some independence. Advantages:

• It reduces implementation time underway.


• It reduces the time of transfer of materials.


• Reduce inventories of work in process.


• It reduces production time.

Disadvantages:

• The products are classified into homogeneous groups from the point of view of the process to assign a manufacturing cell.


• It is necessary to be able to order the machines in each cell in a complex workflow, where all parties follow the same sequence as the machines.

It is recommend for systems with flexibility, allowing to obtain reduced production times.