Using Industrial Hydraulics |
Applications of Computer-Aided Manufacturing
Machine tool operators operate or tend one or more types of machine tools that have already been set up for a job. These tools cut, drill, grind, bore, mill, or use a combination of methods to cut or finish pieces of metal or plastic products.These machines include lathes, boring mills, drilling and screw machines, jig grinders and borers, and milling machines. Some machine tool operators work with numerically con trolled equipment.
At one time, before modern manufacturing procedures, goods were made individually by one craftsworker. As shops grew larger and employed more workers, the process changed. The steps involved in creating a product were separated into a series of easy tasks, which workers could learn quickly and do repetitively. Each worker was responsible for one part of the process Various tools were used in the manufacturing process, even in early times One of the earliest machine tools, the wood lathe, actually dates back to ancient times and is probably a variation of the potter’s wheel It performs by mechanically rotating a workpiece against a stationary cutting tool.
With the advent of the industrial revolution, machine tools became more advanced and more widely used. During this time, lathes were adapted for cutting metal, and by the late 1700s, British inventor Henry Maudslay had devised the first screw-cutting lathe of high quality. By 1775, British industrialist John Wilkinson had invented a boring machine that made holes in metal with precise accuracy. The planer, a metal-cutting device that holds a workpiece in place while a cutting tool moves back and forth, was developed 25 years later. The planing tool allowed holes and flat surfaces to be smoothed to necessary degrees.
Technological improvements in machine tools affected the burgeoning industrial revolution. The use of such tools was, in fact, responsible in part for the design of early mass-production methods in the United States. However, the most rapid spurt in the development of machine tools has come since World Wars I and II. During the wars, it was necessary to build tanks, planes, jeeps, ships, and guns rapidly and accurately, so machines had to be devised that would turn out the thousands of pieces required.
The latest developments began in the 1950s and 1960s with the design of numerically controlled machine tools. A numerical control system regulates the performance of a machine tool by interpreting coded numerical data, which then directs the positioning and actual machining of the tool. Further improvements in machine tools have paralleled the advances in computer technology. Methods from which machine tooling has benefited include computer-integrated manufacturing, computer-aided design, and robotics.
Machine tool operators tend to the operation of one or two machines that have already been set up by a job setter or setup operator. Although some workers are known by the specific machines for which they are responsible (e.g., lathe operator, drilling machine operator), most are trained to work on a variety of machines. A typical machine tool operator, for example, may tend a drilling machine. The operator starts the drill, inserts a piece of metal stock into the guide that holds it during machining, pulls down the lever of the drill press until the piece is drilled the prescribed distance, and releases the lever. Completed parts are then removed from the machine and placed in a bin.
During the machining process, the operator watches to make sure that the machine is working properly. When needed, the operator adds coolants and lubricants to the machinery and the workpiece.
Except during breakdowns or while new stock is being brought up for machining, the machine tool operator generally repeats the same process until the batch of pieces is completed. In some shops, though, an operator tends a series of the machines that shape and finish a machine part, and may even do some programming. Skill requirements vary from job to job. When a new program is loaded, it often must be adjusted to obtain the desired results. A machinist or tool programmer usually performs this function. Because numerical control (NC) machine tools are expensive, operators who work on these more advanced machines carefully monitor operations to prevent costly damage to cutting tools or other parts. The extent to which this is required, however, depends on the type of job and equipment being used. In some cases, the operator may only need to watch a machine as it functions, and therefore can set up and operate more than one machine at a time. Other jobs may require frequent loading and unloading, tool changing, or programming. Operators check finished parts with micrometers, gauges, or other precision inspection equipment to ensure they meet specifications, although NC machine tools are increasingly performing this function as parts are produced.
A high school diploma is preferred by most employers of machine tool operators. Classes in algebra, geometry, and drafting or mechanical drawing are excellent preparation for this job. Machine shop classes are also helpful.
Most workers in this occupation learn their skills on the job. Trainees begin by observing and helping experienced workers, sometimes in formal training programs. As part of their training, they advance to more difficult and complex tasks, such as adjusting feed speeds or changing cutting tools. They also learn to check gauges and do basic shop calculations. Eventually, they become responsible for their own machines.
If you are interested in this work, you should have better than aver age mechanical aptitude and manual dexterity and an interest in machines. The ability to pay close attention to a task, even when it becomes repetitive and dull, is essential. As machinery becomes more complex and shop floor organization changes, employers are increasingly looking for people with good communication skills. Because machine tool operators spend most of their day standing at machines, you should have a certain amount of physical stamina.
Hobbies such as building models and working with wood and other materials provide practical experience in fundamental machining concepts. If you want to explore the occupation further, high school or vocational school shop classes teach technical theory and machining techniques. You might join a student organization, such as SkilisUSA (http://www.skillsusa.org) or the Technology Student Association (http://www.tsaweb.org), if one is active at your school.
If you wish to see machine tool operators in action, you can ask your teacher or guidance counselor to set up a visit to a local plant or you can investigate a summer or part-time job as a general helper in a nearby shop.
According to the U.S. Department of Labor, approximately 91 percent of machine tool operators are employed in manufacturing industries—primarily in fabricated metal product manufacturing, plastics and rubber products manufacturing, primary metal manufacturing, machinery manufacturing, and motor vehicle parts manufacturing.
Shops and plants are most often found in the industrial areas of the Northeast and Midwest as well as California.
Job seekers should apply directly to the personnel offices of machine shops and factories. Entry-level workers start out by doing a wide variety of jobs at the plant, first learning skills by observing experienced workers, and later by working under supervision until they are capable of working independently. This type of training usually lasts about one to two years. Job openings for machine tool operators are often listed in classified ads of newspapers as well as with state and private employment agencies.
Becoming a professional, skilled operator with commensurate wages often takes a number of years. In addition, it is generally only after several years’ experience that a machine tool operator can advance to the position of setup operator. An operator who can read blueprints and use measurement tools, and who is willing to try new methods, is more likely to be moved into a supervisory job or to a more versatile position such as a numerical control programmer or a job setter. Operators may also transfer to training programs for other related occupations, such as precision machinist or toolmaker.
The annual wage for machine tool operators varies according to which machines they run, the size of the facility, and where it is located. According to the U.S. Department of Labor, annual wages in 2006 ranged from less than $20,600 to $46,690 or more, depending on the position. Many workers often work more than 40 hours a week and earn overtime pay. Earnings also vary considerably by industry. Operators who work in the manufacturing of transportation equipment earn substantially more than those who work in rubber and plastic products manufacturing.
Many machine tool firms have traditional benefit plans, including retirement programs to which both the employer and the employee contribute. Most operators are also eligible for paid vacations, sick leave, and group hospitalization insurance. In many manufacturing operations, the plant closes for a period of time to change over machinery in order to make new models. Workers are seldom paid for this downtime.
In general, machine tool operators work a standard 40-hour week, but often, when large orders have to be met quickly, they may be asked to work late and on Saturdays. Work is performed exclusively indoors. Conditions can be somewhat dangerous, particularly because of the high speeds and pressures at which these machines operate. Therefore, protective equipment must be used, and safety rules must be observed. There are other minor hazards as well, including, for example, skin irritations from coolants used on cutting and drilling machines. Operators must wear goggles and avoid wearing loose clothing that could get caught in machinery. Most machine shops are clean, well lit, and ventilated, although some older ones may be less so. The shops are often noisy because of the operating machinery.
The main drawback to this profession is the repetitive and sometimes boring nature of the work. Machine tool operators typically spend hours each day performing the same task, over and over.
However, the fairly high wage for work that is relatively easy to learn and perform may compensate for the tedium of the job.
Employment of machine tool operators is expected to decline through 2014, according to the Occupational Outlook Handbook. The main reason is the change to labor-saving machinery. In order to remain competitive, many firms have adopted new technologies such as computer-controlled machine tools to improve quality and lower production costs. Computer-controlled equipment allows operators to tend a greater number of machines simultaneously, and thereby reduces the number of employees needed. However, employment of operators who are skilled in the use of these machines is expected to increase, while positions for manual machine operators continue to decline.
Also, the demand for machine tool operators parallels the demand for the products they produce. In recent years, plastic has been substituted for metal in many manufacturing parts. If this trend continues, the demand for machine tool operators in plastics manufacturing will be greater than for those in metals. The U.S. Department of Labor predicts that employment opportunities will also be better for multiple-machine-tool operators and molding, core-making, and casting-machine operators, metal and plastic. Employment declines are expected for metal-refining furnace operators and tenders and pourers and casters, metal.
Even with the slow growth and decline in certain positions, there should be many job possibilities for machine operators. It is estimated that within the next 10 years, 60 percent of the existing workforce will be leaving the occupation due to expected retirements and will have to be replaced.
FOR MORE INFORMATION
For information on training and jobs for machine tool operators, contact:
International Union, United Automobile, Aerospace, and Agricultural Implement Workers of America Skilled Trades Department
8000 East Jefferson Avenue
Detroit, MI 48214-3963
International Union of Electronic, Electrical, Salaried, Machine, and Furniture Workers-Communications Workers
301 Third Street, NW
Washington, DC 20001
For literature on training and careers in the machine tools trades, contact:
National Tooling and Machining Association
9300 Livingston Road
Fort Washington, MD 20744-4914
Precision Machined Products Association
6700 West Snowville Road
Brecksville, OH 44141-3212
For useful resources about careers and internships in the metal-forming industry, contact
Precision Metal-forming Association Educational Foundation
6363 Oak Tree Boulevard
Independence, OH 44131-2500
For industry information, contact:
Tooling and Manufacturing Association (TMA)
1177 South Dee Road
Park Ridge, IL 60068-4379