Industrial Engineering

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An introduction to the process of designing work methods – The general procedure for solving problems

An introduction to the process of designing work methods – The general procedure for solving problems

In the general procedure for solving problems, three different phases can be distinguished: i) a definition phase, ii) a search phase and iii) a definition phase.

Definition phase

It consists of determining the characteristics of the problem, that is:

  • The specifications of the initial and final state.
  • Existing restrictions.
  • The criterion (preference).
  • The number of repetitions.
  • The time limit.
  • This includes a description of the data or constraints within which the methods analyst must operate.

Search phase

The search process implies an inquiry regarding the alternative solutions of the problem, that is, the different methods to achieve the transformation of the initial state towards the end.

This process is characterized by an investigation as exhaustive as possible, to later carry out a synthesis. In this phase, the ingenuity and inventiveness of the methods analyst plays an important role.

Decision phase

The decision process consists of evaluating the alternatives obtained, and then choosing based on the established criteria.

In practice, the aforementioned phases of the problem-solving process may have points in common, and it is often necessary to repeat the cycle, with the corresponding feedback, before finding a satisfactory solution.


An introduction to the process of designing work methods – The characteristics of a problem

An introduction to the process of designing work methods – The characteristics of a problem

What are the characteristics of a problem?

Being familiar with the characteristics of a problem is one of the foundations for its solution, since it facilitates the understanding and scope of the design and the procedure that it implies, since the design is, in essence, the solution to a problem that by tradition is entrusted to the engineers.

Solving an engineering problem, including of course related to methods engineering, involves dealing with several different methods to achieve the desired result. If there were no known or unknown alternative solutions, there would be no problem.

If all solutions were equally satisfactory, then there would not be a problem either, however this is usually not the case, since a problem involves finding a preferred method; for example, the least expensive. Therefore, if the preferred method is obvious from the beginning, there is also no problem.

In any problem there is a set of initial circumstances (input, or starting point) and a set of final circumstances (output, goal, or result for which a method is sought). The characteristics of a problem are listed below:

  • The number of possible solutions is, in general, large.
  • Possible solutions to a practical problem are seldom obvious at first. In reality, it is not often that all possible solutions are known in advance, even if prior analysis or research has been done.
  • Alternative solutions are not equally desirable, therefore the preferred solution is sought, for which it is necessary to apply selection or decision processes. In this way, the existence of methods with different degrees of preference enables a fruitful search before making a choice. The base of the preferences is usually called the criterion and in various problems in the business world, this parameter is the profit obtained; This allows choosing the best alternative among various investment alternatives. Therefore, the method sought is the one that maximizes the profit when time, money and other resources are invested.
  • The relative advantage of alternative solutions to a problem is generally not evident, and the search for data, measurements and calculations must be carried out to determine it satisfactorily. 

The cost of time and other resources dedicated to solving a problem must be considered in a reasonable way, since, as with many economic concepts, a point is reached where it is more difficult to find additional solutions and where productivity begins to decline. descend. Thus, while the search for better methods continues, a point in time is reached where better solutions are unlikely to be found that justify a greater investment of time, money, and other resources.

Can a problem be solved perfectly?

There are two reasons why a problem cannot be solved perfectly: i) the time required for such a task would be greater than the life of the problem, which is true for the vast majority of problems in the industry and ii) it is not economically optimal to try to find a perfect solution. It is more economical to direct efforts to other problems that require solutions, before continuing to try to find a perfect solution.

In solving problems, it is not intended to find one that is completely ideal, nor is it expected to find it, since there would be no possibility of recognizing it as such if it were found. The idea that is pursued is to progress towards the ideal solution, looking for better solutions until it is determined that it is not productive to continue with the search.


Investigation of accidents at work - What incidents should be investigated?

Investigation of accidents at work - What incidents should be investigated?

In general, everything related to incidents at work must be monitored by the administration of a company. However, there are several events of a different nature that, due to their possible impact on the normal development of the organization's activities, should be the subject of an investigation. Within this framework, a large part of the country's legislation provides for the investigation of at least those events whose impact or severity is relevant.

For example, when a death occurs in the workplace or accidents that cause severe damage to the health of workers occur, especially if they are recurring, investigation processes are surely required, which is required by the competent authorities in matters of occupational health and safety.

Generally, the competent authorities require a formal investigation and reports in this regard, in the following cases:

  • Any accident with severe damage to the health of workers or death, incidents involving the collapse of structures and situations involving the use of hazardous substances.
  • Incidents that result in workers requiring medical treatment.

Incidents that could have generated catastrophic damage, but did not. In this context, companies can establish standards that help determine the cases in which an incident should be the subject of a formal investigation (these standards must minimally comply with the requirements of the labor authorities). In this way, the occupational health and program of a company could establish, for example, the following criteria to activate an investigation and the corresponding report to the authorities:

  • Any event that causes physical harm to workers, including those that require medical help, or causes prolonged interruptions of normal activities;
  • Any event that requires recurring medical treatment;
  • Any incident that goes against the company's accident prevention policy;
  • Any event that has had the potential to cause physical damage to workers;
  • Any event of serious damage to company property;
  • Any event of poisoning by chemical substances;
  • Any event that has generated a flood in the work environments;
  • Any event that has generated a fire or explosion.

Critical factors in the incident and accident investigation process

Critical factors in the incident and accident investigation process

Incidents that materialize in accidents are generally the result of several interacting factors, which is why area supervisors must undertake accident investigation in coordination with personnel specialized in occupational health and safety. In this way, they must focus on three essential factors: the human, the situational and the environmental or environment.

Human factors

Beyond the training they may have, due to their human nature, the attitudes and way of acting of the workers can become a source for the occurrence of incidents. Thus, the following questions should be asked when investigating the human factors related to an accident:

  • What was the worker doing at the time of the incident?
  • Was he doing a regular or special task?
  • Was he doing maintenance work?
  • Was he helping a partner?
  • Was the worker performing his or her work in accordance with established procedures?
  • Are the tasks or work procedures new?
  • Was the area supervisor present?
  • What was the employment status of the worker? Are you a seasonal, part-time, or full-time worker?
  • How much experience did the worker have to perform the task he was developing?
  • What was the worker's posture and location?
  • Did any unsafe act contribute to the occurrence of the event?

Situational factors (unsafe conditions)

The analysis of possible unsafe conditions is a central element in the investigation of accidents, so the equipment and tools must be carefully examined. In this sense, the following questions should be asked when carrying out the analysis of situational factors:

  • Was he being the machine properly?
  • Were the controls working properly?
  • Were the security measures working satisfactorily?
  • Did the analysis of materials or equipment indicate how the accident occurred?
  • What was the place or location of the incident?
  • What tools, equipment or objects were involved in the incident?
  • Was the right equipment available to do the job?
  • Was personal protective equipment being used?
  • Were the machinery guards in place?
  • What time did the accident occur?
  • What work shift were you operating at the time of the incident?

Environmental or surrounding factors

Environmental factors such as light or noise can increase the likelihood of an incident occurring. For example, if the reflection of light prevents a machine operator from seeing clearly, this could lead to an accident. Likewise, the noise generated by some machine could prevent hearing the movement of vehicles or people in the work area.

Critical factors in the incident and accident investigation process

Critical factors in the incident and accident investigation process

The investigation of incidents and accidents is closely linked to the opportunity, severity (ie impact) and legal requirements.

The opportunity in the investigation of incidents and accidents

Opportunity is a critical factor in the investigation of incidents and accidents, since time has a crucial impact on the generation of any type of information. Delays in an investigation could cause the parties involved to partially or completely forget the circumstances of the occurrence of an accident, in addition to changes in the place of the event or the loss of valuable evidence.

In the case of people, if the investigation is not started in a short period of time, it is highly possible that the details of the circumstances of the accidents present distortions and the witnesses do not provide reliable and accurate information.

The investigation process should start immediately after people who may have been affected by an incident are cared for and the scene of the incident is secured to prevent further harm.

The severity or impact

Since any investigation requires time, companies must prioritize the allocation of more resources to those incidents with the most relevant consequences. This applies even to accidents that have not generated significant damage, but due to their characteristics could have a significant impact at some point.

Thus, it is recommended that the following types of incidents be investigated with greater emphasis:

  • Those that result in damage that generates a loss of time beyond the day of the incident;
  • Those in which the personal damages have been minor, but the potential damage has been high.
  • Incidents with property damage greater than USD1,000;
  • Incidents with loss of time resulting from the aggravation of previous damage.

In general, beyond the system used by a company to determine the severity of an incident, there is a legal obligation to report all incidents that result in personal injury to employees.

Legal requirements

Depending on the severity of an incident, the presence of physical damage and the jurisdiction where it occurred, certain reporting requirements to the competent authorities must be met. Certain types of events, such as those in which medical help is required or result in significant loss of time, must be reported to special instances related to workers' compensation mechanisms.


Investigation of incidents and accidents in occupational health and safety

Investigation of incidents and accidents in occupational health and safety

Incident investigation is a fundamental component of any organization's occupational health and safety program. Different studies identify the benefits of incident investigation as follows:

Direct determination of the causes: An investigation reveals the direct causes of an incident, allowing corrective measures to be established.

Identification of associated factors: Incidents can be the result of many factors, for example, the direct cause of an incident can be the inadequate use of protective equipment on the machines, however, there can also be associated factors, such as the lack of training in handling equipment.

Prevention of similar incidents: Once the direct causes and associated factors are identified, corrective measures such as training programs or improvements in the design of equipment or workplaces are implemented to prevent similar incidents in the future. 

Creation of permanent reports: The reports generated in an investigation can be used by the human resources area and occupational health and safety specialists to identify trends related to the frequency of incidents, inadequate plant design and layout, inadequate operating procedures, etc. Reports are also important in situations where compensation disputes or claims arise. The actions taken to improve occupational health and safety records contribute decisively to adequately allocate monetary, human and equipment resources to the areas with the highest frequency of accidents or to those where the effects are most harmful.

Determination of associated costs: The reports help to understand a certain situation more precisely and therefore to quantify and determine the costs associated with the occurrence of an incident. All factors, including lost time by workers, damage to equipment and machinery, loss of supplies and materials, etc. they are likely to be quantified, a task that can be better accomplished from the reports that are part of the incident investigation.

Promotes a culture of employee safety: When an incident investigation is conducted appropriately, it signals to workers that top management takes occupational health and safety seriously, seeking to maintain the well-being of employees. The foregoing motivates the company's workers, regardless of the area where they work or their rank, to have a greater commitment to good safety and health practices in the workplace.


The techniques used in the “pull” production system

The techniques used in the “pull” production system

The "pull" manufacturing system is characterized by producing only what is required, minimizing inventory in process. To achieve this end, several particular approaches have been created, such as those described below:

Just-in Time: In which only the appropriate components, at the precise moment they are required, are manufactured.

Kan-Ban: It is a paper record that enforces just-in-time, moving with each batch of components. This can be automated using barcodes, QR codes, etc.

Manufacturing cells: Combine the requirements of a variety of products so that a set of equipment can produce each of them, as needed. This mainly applies to manufacturing and sometimes to assembly.

Batch-of-One: Refers to the ability to make any combination of items with a batch size as small as one.

Continuous improvement: Refers to the ability to find ways to improve current processes, often by combining and/or eliminating manufacturing activities.

Statistical process control: Referred to monitoring how well the process is working.

The manufacturing process had played a secondary role in product design for most of the 20th century, resulting in many problems when it came to manufacturing the products. While major aspects of manufacturing processes have been researched and implemented in physical devices for many years, the assembly process had very little beyond the rules of thumb to guide it.

Ideas for improving assembly capability and for designing cost-effective manufacturing systems only began to flourish in the late 1970s. During this period, many individuals and companies began to realize that the most rational course of action involved design. of products and the design of manufacturing systems together, which is called concurrent engineering or simultaneous engineering. A more recent term, which involves the entire company as well as suppliers and customers, is known as collaborative engineering.

Manufacturing methodologies – the pull and push systems

Manufacturing methodologies – the pull and push systems

Traditionally, there has been a clear separation between the creation of a product and the means through which it is produced. In much of the 20th century, manual production methods were used in different processes, especially those in which assembly was present. However, many important design decisions were worked on behind a desk.

Between the late 1970s and throughout the 1980s, manufacturing industries of all types and sizes wanted to know how they could replace their manual production methods with better processes. In this way, large companies that produced larger volumes of a product determined that automation was the best solution. In this way robots and other programmable machines were developed. Manufacturing plants of this era were characterized by having work-in-process inventory that took up large amounts of space, creating significant costs that did not generate revenue.

In the 1990s, up to the present day, industries of all sizes need to be agile and flexible, so a new paradigm in the field of production was introduced. This approach means that companies are looking to have the ability to respond to any customer very quickly, while minimizing their costs. Thus, the production philosophy changed from making a stock of some product to manufacturing on demand, which required rethinking the way in which production processes should be carried out.
In this framework, Toyota introduced the approach of producing only what is required, with which the "pull" method replaced the "push" method.
 
In the “push” production method, each stage of the manufacturing process ran at the highest possible speed, regardless of what happened in subsequent stages, which meant having significant batches of inventory in process. To optimize these processes, elaborate simulation methods were created.

In the "pull" method of production, each stage of the manufacturing process works only when the next stage provides notice that it requires inputs. Viewed another way, each step in the process has a customer, either internal or external, to which it responds. Using this system, inventories in process are minimized, being completely eliminated in many cases. The analysis of such a manufacturing system is much less complex than traditional simulation methods.
 
Producing only what is required is a fundamental concept of "pull" manufacturing systems, which minimizes in-process inventory. Work is not done in any area until the next level says it is ready for input.

Adds

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Accidents (8) Activities of industrial engineering (6) Batch of one (1) Continuos improvement (1) Costs of accidents (6) DEFINITIONS (17) Domain of industrial engineering (1) EDUCATION AND TRAINING (1) EVOLUTION OF INDUSTRIAL ENGINEERING (16) GETTING A JOB (2) Health and Safety at Work (10) Health and safety management (5) HISTORY OF INDUSTRIAL ENGINEERING (24) HS (1) HSE (6) HUMAN FACTORS AND INDUSTRIAL ENGINEERING (6) Industrial accidents (3) INDUSTRIAL AND SYSTEMS ENGINEERING (5) Industrial engineer job (9) INDUSTRIAL ENGINEERING (20) Industrial engineering functions (4) INDUSTRIAL ENGINEERS (2) Industrial revolution (1) Industrial Safety (9) Inputs (1) Investigation of incidents and accidents (4) Just in time (2) Kan-ban (2) Machine accidents (2) Manufacturing methodologies (2) Measure of productivity (3) Methods design (5) METHODS ENGINEERING (11) Motion and time study (4) Non machine accidents (3) Occupational health and safety (4) OPERATIONS RESEARCH (1) Outputs (1) Performance measurement (2) POSTGRADUATE CURRICULUM (1) Process analysis (5) Production engineering (2) Production systems (4) Productivity (6) Pull system (2) Push system (2) Quality control (1) Reporting (4) Solving problems (2) Statistical process control (1) TOPICS RELATED TO INDUSTRIAL ENGINEERING (11) Types of productivity (3) UNDERGRADUATE CURRICULUM (1) WHAT INDUSTRIAL ENGINEERS DO (7) WHERE INDUSTRIAL ENGINEERS WORK (6) Work simplification (9) Work study (2) Workplace design (2) Workplace desing (2)

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