# What are some of the topics the industrial engineer studies?



## Shibani (25 يوليو 2007)

What are some of the topics the industrial engineer studies?

_People_

This area is what sets industrial engineering apart from the other engineering disciplines. The IE undergoes several courses in psychology and social science to help them understand some of the work place dynamics involved in managing people. It also helps them develop effective methods of dealing with these problems. Other areas of concern for the IE are how many people are required, is the job designed correctly for a human operator (Ergonomics), is the operation safe, what level of pay should be offered for the work, does the job require the employee to get more training, and is there good communication between management and their employers.

Manpower Requirements
To understand the manpower requirement a great deal of time study and motion study activity will need to occur. Depending on the company’s policies for setting work standards one of several methods will be chosen.
Performing a motion study. Every job can be broken down into its’ fundamental work elements. The Gilbreth family found that there are seventeen of these motions. The time to complete each motion does not change. This is the important part. Jobs can be studied visually or through the assistance of a camera for micro-motion studies.
Whether the study is visual or micro the IE will be applying the same rules of motion economy to the person, environment and tools. The rules that are applied to the person, intend to help the person move in a more balanced and synchronized manner. For example, both hands should begin and end moving at around the same time. Foot pedal devices should only be used when the operator can sit down.
The environment for the workers also needs to be set up to promote efficiency of work. Tools should be placed in fixed locations to eliminate the search and selection therbligs. Work surfaces and chairs should be adjusted to the correct working heights to eliminate stress. Whenever possible, gravity feeders should be used to deliver parts to the correct location. The worker's tools should be designed to eliminate multiple cuts. Adjustment handles should be designed to maximize the operator’s mechanical advantage.
The process above is a continuous process. To stay competitive companies must continue to increase the production capacity of their facilities while reducing their cost. The IE will be expected to come up with additional improvements each year.
Performing a time study. Without a standard the company will find it hard to estimate lead-time on their products. Times very greatly when the employee does not know what the expectation of company is. In order to correct this problem the IE will develop a fair standard expectation for each operation. It has been estimated that 12% of a company's total cost comes from direct labor. Another 43% of cost comes from the material cost. The other 45% is spent in overhead. So the idea that the largest productivity gains can be felt on the floor does not hold up in this light. Standards will be set for all parts of the company not just the operations performed by the direct laborers. The IE will be involved in analyzing and standardizing office work as well.
A good time study will take into account the unavoidable delays, fatigue, and to an extent, outside interferences. Time for wasteful steps, such as searching for tools, will not be included in the final standard. The expectation is that the workplace will be designed to accommodate the work and will be free from this type of waste.
By setting a performance standard the company can look at the schedule for the next year and determine if they have the proper amount of manpower. Prior to establishing standards the company would have to go on their gut feelings about the current capacity and need for additional help.

Ergonomics
The idea of mass production is to take a complex job and break it down into simple and repeatable task that can be performed with a high level of precision by the same set of operators. If the workstation, task, and environment are not designed properly the worker will be subjected to safety and health risk. Companies sometimes choose to ignore violations do to cost; however, with the current health care prices, the company could easily find itself paying triple the original cost. The IE should be aware of these issues and work with management to resolve them as quickly as possible.

Compensation
From the company's point of view they want to minimize the amount of money they have to pay to the employees. This goal often goes against the other goal of management and that is productivity. The productivity of the employee is directly linked to the monetary rewards for the employee. There are several plans that have been developed over time with the intent of balancing the cost with productivity.
An IE will help the company analyze their current situation and will often be responsible for suggesting an appropriate plan. After a plan has been decided upon the IE can be instrumental in its success. Some examples of plans are: piece rates and standard labor hour plans, gain-sharing plans, employee stock ownership plans, and profit-sharing plans.

Training
The operators must be appropriately trained. Standards are set using people that are familiar with the job and people who have mastered the skills required to perform the job. If other individuals are going to be expected to perform at this level then they will need to be trained.
In a competitive market the employees become even more valuable, but if their training is not kept up to par then the company's most valuable asset is losing value. As new processes and methods are developed it is the responsibility of the IE to help make sure the proper level of training is administered.


_Machines_

Capacity
Where the mechanical engineer and manufacturing engineer will be concerned with the specific machine abilities and tooling requirements, the IE will be looking at the amount of time it will take to set-up the machine, the cycle time of the machine, the number of operators required, the foot-print size, the power requirements, as well as the ergonomic design.
While the mechanical and manufacturing engineer will also be interested in the above information they will not be making their selection based on these criteria. However, the IE needs to integrate the equipment in a predefined production environment. If the machine is too large it may not fit into the area allocated for it. If the machine runs too fast then the company is buying excess capacity that may not be able to be used. If the machine runs to slow then the company is injecting a bottleneck into the system. The bottleneck will regulate the output of that part of the system. These are the types of considerations that the IE goes through during the selection of a machine.

Mobility
The size of the machine and the energy requirements are very important if the equipment is going into a cellular environment. If the machine requires a separate foundation then it becomes a monument in the plant and the flow of parts must be compensated. Unless it is unavoidable, smaller less expensive equipment should be purchased, even if minor enhancements are required. This is usually a better practice then buying a more expensive machine and only using 20-40% of its’ functionality. This will also help the company to remain competitive by reducing the amount of invested capital. A group of specialized people can be developed in house for the purpose of machine modification. By buying less expensive machines and then modifying them the employer will have specialized equipment not available to their competitors and this will help give them an added edge.

Set-Up Times
Set up time is the amount of time it takes to begin producing different parts on a machine. For example, this time would be calculated from the last good part, type A, to the first good part, type B. It is extremely important that this time be minimized so the economic lot size can be shrunk. If set-up times remain large the company will operate with high levels of work in progress and finished goods tying up the companies valuable capital. Companies that fail to reduce their set-up times have a tendency to look sluggish in regards to their customers.

Cost
An IE will generally be responsible for coming up with a cost analysis on the equipment purchase. There are a several ways of coming up with this. The IE or the upper levels of management will decide upon the specific method.

Life Time
The IE will also take into account how long the machine is expected to last when developing the cost analysis. A straight-line depreciation may be decided upon over the machines life. The salvage value, or the value of the machine at the end of its’ useful life, is also taken into account.

Efficiency
The traditional way of looking at efficiency was to keep the machine running at a 100% whether the products can be used or not. The idea was that the cost of the machine could be spread out over the amount of time it was kept running. Therefore the higher the machines efficiency, time running / time available, the better the accounting numbers looked in regards to machine cost. This tended to increase the work in progress as well as build finished goods inventories, which is undesirable.

Maintenance
The amount of maintenance that the machine is going to require is a variable that must be considered by the IE before the machine is put into the system. All machines are going to require some amount of maintenance, but care should be taken when selecting machines so maintenance time is minimized.
Another issue about maintenance is whether or not the staff on hand will need to be retrained. The OEM may require that a third party perform the maintenance on the machine, if so the cost of this service should be included in the overall cost analysis.


_Material_

The IE is concerned with the delivery and flow of material throughout the plant. It is nice if the plant has been planned with material flow in mind, but often the plant has evolved as the company has. This can lead to a poorly outfitted facility that could be hindering higher levels of production.

Facilities Layout
Many IE are employed to evaluate the needs of a company and then design a facility that can accommodate these needs. Planning starts with the geographical selection and location. Research must be done into the local compliance codes. The planner will need to determine if there will be adequate access to suppliers and the local transportation industry.
Based on the head count in the facility the IE will need to ensure that there is enough water, adequate restrooms, and cafeteria or local food service available. If the employees will be driving cars to work then an appropriate parking lot will need to be set up.
Beyond that the IE will also be responsible of laying out the equipment and material storage locations for the plant. The key part of this analysis is how things will flow through the plant. You don’t want the parts to travel any further then they must. Traveling is a form of waste that needs to be minimized.

Lot size
To allow the manufacturer to stay flexible the production lot sizes should be minimalized. This will only be economical after the reduction of machine set-ups have been achieved. An IE can look at the lot size of a company as an indicator of flexibility of a company.

Economic Order Quantity
This is one of the calculations that can be used to determine the quantity of material that should be ordered to minimalize the shipping and additional cost of raw material. This is a one form of a linear equation, an example of using methods development by the operations research scientist.

Inventory Levels
Since inventory is capital that cannot be converted until finished and purchased by a consumer, it should be kept to a minimal. Inventories not only tie up capital but they reduce the flexibility of the supplier. If the customer requests a change then the inventory runs the risk of becoming obsolete. The cost of this outdated inventory will, more then likely, have to be written off by the host company.

Quality
The quality of the material can affect all parts of the system. Poor quality material often introduces excessive amounts of rework into each of the processes. If the company accepts poor material then their product will possibly end up shoddy and may or may not cause the company to loose business. A typical job for an IE would be to work with the quality department to set up a Total Quality Management system TQM.


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