Introduction

Did you know that manufacturing can be defined in technological and economic terms?

From a technological point of view, manufacturing is the application of various processes in order to modify the properties of the raw material and convert it into a finished product.

From an economic perspective, manufacturing involves the act of adding value to a material or series of materials by transforming them, through various manufacturing or assembly processes (Groover, 2018).

The core components of manufacturing systems are the activities related to work design, standards and methods. It is at these points more than anywhere else that the intervention of engineers influences the competitiveness of the manufacturing of a product through efficient design of the man-machine relationship, tools and workstations.

The creativity of an engineer provides for the improvement of existing products and working methods. The objective of the manufacturing system is to lay the foundations for the production of quality products, at the lowest possible cost and on time, with the minimum use of capital and with the maximum self-fulfillment of the worker.

When a manufacturing system has been finalized in its design and put into operation, the problems that its operation will present are those related to the analysis and control of the activities of such system. Generally speaking, there are issues related to the flow of products through the plant, the scheduling of production, the sequence of manufacturing orders, and how production activities should be kept on schedule.

Another aspect that tends to generate problems is related to production volumes and the right time to start production. An additional problem related to production plans is the determination of the optimum production batch.

In addition to the above, there are a number of other problems related to the operation of manufacturing systems that by their nature fall outside the scope of our discussion. However, you should not forget that there will always be a better method of doing the necessary work. The search for continuous improvement in the production activities of a plant is the task of the "method analysis".

An element related to the operation that should not be forgotten within manufacturing systems is the measurement of work, whose methods include the time study with stopwatch, synthetic and the standard data method.

Explanation

1.1 Basic definitions of a manufacturing system

A manufacturing system is an organized procedure that is executed to achieve the conversion of inputs in useful goods or services. A schematic representation of a manufacturing system is shown in Figure 1:


Figure 1. Basic manufacturing system.


The main characteristic of a manufacturing system is input conversion through a productive process.

The definition of manufacturing requires that the produced product (goods or services) is different from the raw material. If there is no difference, it may be a storage or distribution system or some other, but it is not a production system.

In a manufacturing system there are three variables that determine the response of the system:


 

The result at the end of the production process is the generation of new goods or services.

1.2 Design of activities in manufacturing systems

In the design of the activities of a manufacturing system, nine main analyses are used, which form a systematic method of analysis of the activities that will be included in the system, the nine main analyses are the following.

Click on each type of analysis for more information.

It answers the questions: what is the operation for, is it necessary, can it be eliminated without consequences? can it be combined with another?

It is necessary to review the design of the parts in search of improvements.

Closed tolerances are sought and opened where they are not really needed, there should only be closed tolerances where they are required for the correct functioning of the part. There is what is called economy of tolerances, the more demanding the tolerances of the parts, the higher the manufacturing cost.

The least expensive and easiest to process materials should be sought after, materials should be used in the most economical way, materials should be standardized, and the best supplier should be sought after in terms of price and availability.

When a change is made in one operation, possible consequences in other operations should be sought after, the mechanization of manual operations, the use of better machines and tools in mechanical operations, and the most efficient operation of mechanical devices and installations will be sought after.

This concept refers to scantlings, which is a pattern or guide to follow in the construction or manufacture of an object and the tools necessary to carry out a process. The main element to consider in all types of tooling and configuration (preparation) is economics. The optimal number of tools for the process depends on the number of parts to be produced, the possibility of repeating part production, the delivery conditions and the capital needed.

The main objective of a material handling system is unit cost reduction, and it refers to having the material, at the right time, in the right amount and in the right place.

The main objective of the effective layout of equipment in the plant is developing a production system that facilitates the manufacture of the desired quantity of products at the lowest possible cost. The type of plant layout depends on the type of process being used.

It has to do with improving the arrangement of the parts at the workstation, the movements required to perform the task and the design of the workstation itself, i.e., it is the natural field of application of ergonomics. The golden rule in job design is the following: "The operation must adapt to the worker and not the worker to the operation" (Niebel and Freivalds, 2013).

 

 

1.3 Planning and control of activities for manufacturing systems

The different activities that make up the system must be planned in terms of their design, whose rules were exposed, and in terms of the number of times they will be used in the different production processes of the organization. These activities should be controlled by the industrial engineering area in terms of their application, according to the design and improvement that can be made of them.

The main control parameter of the activities of the manufacturing system will be the standard times determined for such activities and their proposed methods. The way to control these two elements is through periodic audits to ensure compliance with these, both times and methods. When monitoring is not used as a control method, it is very likely that the proposed methods deviate to inappropriate methods.

Two other critical elements in the control of a manufacturing system are production and cost control. Production control it is the activity of the manufacturing system responsible for the programming, route determination, expediting and monitoring of production orders, trying to reduce costs and meet the requirements of the organization's customers. The basic control method for production control is scheduling.

Production scheduling is handled on three levels:

  1. Master scheduling:

    The master production plan is a medium-term plan where the times of obtaining supplies and the production of products are considered in advance. The master plan is a dynamic plan, as it adjusts to demand, introduction of new products and orders from new customers.
  1. Scheduling of accepted orders:

    The schedule of accepted orders is a short-term program in which the start and end dates and volumes of production orders that have been accepted by the company are already displayed, it is the basis for the realization of the detailed schedule of the operation.
  1. Detailed schedule of the operation or loading of machines:

    The detailed program of the operation is a very short-term program, in which the production load that the production lines or machines used in the manufacture of the products is shown in detail, based on the orders that must be made. It can be so detailed that it shows the daily production schedule of the plant

Each of the three levels of production scheduling increases the level of detail of the program, being the operation the most detailed of all, it is the program that specifically assigns the operations to the different production lines or machines.

It should be noted that none of the three types of production schedule would be possible without the existence of time standards. Time standards provide the information to determine the production flow and the work in progress, this information is necessary for scheduling with a good degree of accuracy.

As in any other activity that is based on the management of information, the accuracy of it, provided by the standard times, determines the accuracy of the schedules that are generated from them. Without the existence of time standards, no production program of any level can be reliable.

The manufacturing costs are classified into four groups:

  1. Direct material cost: the direct material cost is the unit cost assigned to the raw material that will be used in the manufacture of the products. The calculation of the direct material cost does not involve materials that are not part of the products, even if they have been used for their manufacture, the cost of the latter type of materials will be included in the manufacturing expenses.

  2. Direct cost of labor, manufacturing expenses and overhead: direct labor cost is the cost of personnel directly involved in the processes necessary for raw material transformation, meaning, it only includes the personnel who transform the raw material. It does not consider the cost of manufacturing support personnel, such as maintenance personnel, material handling, quality control, among others.

    The cost of this last type of personnel is quantified within the manufacturing expenses, which includes the non-productive inputs and energy used to produce the products. Overhead includes all expenses incurred for the operation of the plant, excluding direct costs and manufacturing expenses. Overhead includes administrative costs. The manufacturing cost results from the sum of the above four elements.

  3. Standard cost: it should be carefully determined from the manufacturing cost plus a normal variation factor. The standard costs become goals that must be achieved and that are used in the preparation of budgets and performance evaluation of actual manufacturing costs.

  4. Actual costs: they may differ from standard costs. The way to control these is through the comparison of standard costs with actual costs computed during a production period. The variations between these two costs can be favorable or unfavorable to the organization, if the actual cost is less than the standard, the variation will be favorable and vice versa. Knowledge of variations provides the organization with the necessary information on the changes required to operate the manufacturing system in a profitable manner.

Example:

A metal manufacturing company wants to add a new product line to its current catalog. The inputs of the new production line will be the space to be used, the necessary equipment, raw material, labor, manufacturing methods, systems, administrative personnel, operating capital, and so on.

Manufacturing engineers determine the method, machinery, floor space and labor to be used. Based on the information above, they determine standard manufacturing times and costs along with the finance department. The materials department receives information from the sales department and together with the production department they draw up the detailed production schedules. Once the installation of the machinery and the initial tests of the manufacturing system have been carried out, the manufacture of the new products begins.

At that moment the manufacturing engineers start the control of standard times and methods designed for manufacturing; the materials and production department start the production control and the finance department will compare the standard costs with the actual manufacturing costs to detect variations. Any variation that is found by the different control processes must be corrected immediately in order to maintain an efficient operation of the manufacturing system and achieve or exceed the different established goals.

Glossary

  • Standard time: time determined as necessary to perform an operation under normal conditions by a qualified worker for the performance of this. There are various methods for the determination of standard time.
  • Master scheduling: Long-term scheduling based on customer or market demand. No orders or sequences are scheduled and only the expected production volumes are considered and scheduled for the appropriate deadlines.
  • Scheduling of accepted orders: It is the scheduling of customer orders to be fulfilled in a cost-effective manner for the organization.
  • Detailed schedule of the operation or machine load: It is the daily scheduling of production, with the assignment of work for the different machines or production lines involved. It is the production program with the highest level of detail.
  • Direct material cost: It is the cost of the raw material required for the manufacture of a product.
  • Direct labor cost: It is the cost calculated from the amount of time required for labor to manufacture a product multiplied by the cost of that time.
  • Manufacturing costs: It includes the cost of indirect labor, tools, machinery and energy.
  • General costs: The costs of administrative staff, rent of premises, insurance and various services are included, everything necessary to support production.
  • Standard cost: It is the estimated cost from the estimation of the four elements of the total cost of manufacturing.
  • Actual cost: It is the cost determined from the accounting of the actual costs incurred during the production process. Generally, all costs related to the manufacture of a product are established as costs per manufactured unit.

To learn more about the current trends in manufacturing systems, check out the following video:

Click on the icon to watch the video

Bernard Marr. (2022, January 24). The 7 Biggest Future Trends In Manufacturing [Video file]. Retrieved from https://www.youtube.com/watch?v=gEPTFlIcKqs

The following link do not belong to Tecmilenio University,
when accessing to them, you must accept their terms and conditions.

 

Conclusion

The main element for the achievement of a good manufacturing system and its subsequent continuous improvement and, therefore, productivity it is the uninterrupted use of the fundamentals of methods, standards and design of work. It is the only way to achieve this and obtain a higher productivity from the manufacturing system designed and put into operation.

The principles of operations analysis are in themselves a method and a system for the analysis and design of what we want to happen on the production floor. These principles are applied in the planning of a new job, as well as in the improvement of existing ones. As a result of this methodology, we can achieve waste reduction, increases in production and improvements in product quality.

Regular and constant monitoring of the standard times and methods implemented ensures that the expected benefits of its implementation are achieved. This means that there must be a periodical inspection to ensure the implemented methods continue to be used on the shop floor, as this is the only way to ensure that this happens; thus, guaranteeing that the plant's efficiency is continually sustained.

If the efficiency of the manufacturing system is not measured continuously, it will be impossible to improve it and it is very likely that it will deteriorate over time because it is not being controlled. The last thing that a manufacturing organization should allow is that its productivity does not continuously increase, since its competitiveness will immediately deteriorate with the negative consequences of such deterioration.

Now that you know the general concepts of manufacturing systems, you will move on to the next topic, to review in greater depth the important concepts of manufacturing planning and control.

Checkpoint

Make sure that you:

  • Distinguish the basic elements that make up a general manufacturing system.
  • Identify the steps in the design of the activities of a manufacturing system.
  • Understand the planning and control phases of the activities of a manufacturing system.
References

  • Groover, M. (2018). Automation Production System and Computer Integrated Manufacturing (5th ed.). United States: Pearson.
  • Niebel, B., & Freivalds, A. (2013). Niebel's Methods, Standards, & Work Design (13th ed.). United States: McGraw-Hill.
Additional Resources

The following links do not belong to Tecmilenio University, when accessing to them, you must accept their terms and conditions.

Videos

To learn about the evolution of manufacturing systems in the automotive industry, check out the following video: 

To learn more about the most relevant manufacturing processes that are currently applied, check out the following video:

Readings

To learn more about supply chain cost-reduction and management, we recommend reading :

To learn more about manufacturing trends, we recommend reading:

Activity 1. Introduction to manufacturing processes

Description:

Through an information search and classification, the student will identify the main characteristics of the elements that make up a generic manufacturing system and carry out the implementation of several of these.

Objective:

To identify and implement the main components of a manufacturing system.

Requirements:
  1. Recycled paper sheets of any size.
  2. Read the chapters marked in the bibliography of the topic.

Textbook:
Groover, M. (2018). Automation Production System and Computer Integrated Manufacturing (5th ed.). United States: Pearson.

  1. Chapter I. Introduction
  2. Chapter II. Manufacturing operations

Instructions:

  1. First, read the suggested textbook and prepare a synoptic table where you include all the components of a manufacturing system and highlight the main characteristics of each of these.
  2. Then, carry out the planning of a manufacturing system, following the following instructions:
    1. It is desired to produce envelopes for money using recycled paper sheets as a base. Each envelope must have a standard size and possess a unique identifier.
    2. The estimated production is 60 envelopes per 30 minutes.
    3. Include the following elements in your production plan:
      • Inputs, production process, finished product.
      • Activities involved in the manufacturing system.
      • Planning and control systems of activities.
      • Fictitious cost plan representing the costs involved in the process.
      • Manufacture five envelopes, measure the time you invested and evaluate the results obtained from the estimated results during the planning for a person who works directly in this process.

  3. Finally, develop a report that includes all the data of the plan. Incorporate a small personal reflection on the learning carried out in the activity.
Evaluation criteria:
  1. Prepare the synoptic table with the requested elements.
  2. Identify the inputs, the production process, and the finished product.
  3. Identifies the elements of production planning and control.
  4. Draw up the cost plan and evaluates the practical results based on the planned results.
  5. Prepare the report incorporating your personal conclusions about the activity.
Homework

Description:

The student will compare Mexico in the field of manufacturing through research and perform a graphic analysis where he/she includes at least three companies in terms of inputs to manufacture their products, the production process to transform them and finish them. Finally, the student will write a report with his/her conclusions.

Instructions:

Individually.

  1. First, answer the 17 questions of the review question section from chapter 1. Introduction of the textbook, click here.
    Groover, M. (2018). Automation Production System and Computer Integrated Manufacturing (5th ed.). United States: Pearson.
    1. Chapter I. Introduction
  2. Next, conduct research in which you compare how Mexico is doing in a certain manufacturing area, such as car manufacturing, per capita income per manufacturing activity, the number of assembly plants installed in the country, among others, compared to other countries. Include the following in your research:
    1. The graph or table where you compare Mexico with other countries.
    2. Explain what the table or graph refers to, as well as terms used in it.
    3. Your analysis or point of view on the position that Mexico occupies in the table.
  3. Then, do some research about three manufacturing companies that work in your region and identify the following points for each of them:
    1. The inputs used to manufacture their products.
    2. The production process used for the transformation of inputs.
    3. The finished products.