Getting the Power to Control
One of the advantages of using machines to control processes
for you is that you can harness tremendous amounts of power
and energy which humans do not possess. By a flick of a switch, huge sliding flood gates can move to
allow large quantities of water to flow out of a dam. With
just a slight twist on a handle, supertankers weighing
hundreds of thousands of tons are able to turn because of the
corresponding rotation of huge rudders. Similarly, processes operating valves can be remotely operated
to control flow, temperatures, pressures and so on. All these final control elements - flood gates, rudder,
valves - must be operated by actuators. The function of the
actuator is to move to control elements in the processes. In order to move the actuator, there must be a medium for
transmitting the required power or action. All the actuators
are mechanical in nature. The common means of transmitting the
power are: pneumatic (air), hydraulic (fluid), and electrical
(motors). The actuators must be designed to work for that medium. There
are several advantages and disadvantages for choosing a
particular medium. For example, pneumatic actuators are
particularly useful when the atmosphere contains flammable
gases. By using pneumatic actuators, there is very little
chance that a spark can be generated to cause a fire. However
using air for actuating may be more expensive to install and
to maintain. Using electrical motors to drive gearing may be an excellent
choice when cost is a consideration. Electrical wires can be
laid more easily and electrical systems are relatively clean. Use of hydraulics may be excellent where power and simplicity
is important. Most of the actuators operate in a linear (straight line)
manner. Hydraulic rams, and pneumatic diaphragms work in this
manner. There are also some that are constructed to operate
in a rotary manner. Electrical motors normally operate in a rotary manner. However
if a linear motion is needed, this can be obtained by means
of spur gears, rack and pinion arrangements, crank and other
means. Actuators can provide the power to move final control elements,
but do they know when to stop? A good control system will provide the sensing and feedback
loop to tell the actuator when to stop its actions. Well folks, be in control! "Tap the Traditional Effective Information Source!" Magazines
contain more information for you. Use them to as your tools!
"Obtain QUALITY INFORMATION through these time-tested media!" Many years of working experience in Marine, Facilities,
Construction has given the author material for writing e-books
and articles related to engineering, and management. Subscribe to facworld ezine
More information at Marine Engineer and M & E Engineer
Related News
|
 |
|
|
RELATED ARTICLES
Top Ten Air Purifier Questions
1. Do I really need an air purifier in my home?
Be Cool and Comfortable While Saving Money
The cost of energy is on the rise, so if you want to have better air quality and feel more comfortable, you must be prepared to pay for it. People in homes and businesses are looking for ways to save money and still remain comfortably cool. Purchasing a portable air conditioner is one way to lower your energy costs. Central air conditioning an entire home is expensive. The portable model will cut down on the cost by only spot cooling the room you wish. Ceiling fans help circulate the air while a dehumidifier takes the moisture out of the air. These two work in tandem with portable air conditioners creating totally comfortable surroundings. Your sunroom might be the warmest room in the house or your bedroom might be located on the second floor.
The Importance of Bedroom Design in a Home Decoration Project.
A home is a place where we live, spend most of our lives,
with family members and our loved ones.
Swimming Pools ? Lets Get Wet
"Beverly Hills. Swimming pools. Movie stars."
Poster, Print or Painting - Where Are You Going To Put It?
If you are redesigning or decorating a room, or house, care has to be taken where your piece of art is to be displayed. Even if you have bought a picture on impulse there are a few tips that will not only enhance the picture but its surroundings.
10 Common Uses for Baking Soda
Baking soda is a great household cleaner. Here are ten ways to clean your home with baking soda:
The Secret to Your Home?s Interior Design
The secret to your home's interior design is Love.
What to Look For in a Drill Press
A drill press, also known as a pillar drill, is the stationary form of a hand-held drill. The advantage of the drill-press over the hand drill is the tool's accuracy and power. A drill press is a very valuable tool with several different types and models of drill presses to choose from. Here are a few things to consider when purchasing your own drill press.
Carbon Monoxide Can Be Deadly--Early Detection Monitors Make It Easy to Protect Your Family
If you burn gas, kerosene, or wood in your home to produce
heat for cooking or warmth, you need to monitor the level of
carbon monoxide. Carbon monoxide is odorless and can easily
build up to dangerous levels. Ordinary carbon monoxide
detectors don't sound an alarm until certain levels of
carbon monoxide accumulate in the air. New monitors show the
amount of carbon dioxide in the air at any given time, so
you can take action well before levels reach the danger
zone.
Outdoor Kitchens ? Simple and Sophisticated
After September 11, many of us decided to stay closer to home. We are electing to remodel our existing homes instead of buying new and moving. We are also entertaining in the backyard more than ever, so it is a natural progression to take what we love about our hearth and home and put it all outside creating the perfect outdoor room. If you have never thought of installing an outdoor kitchen before, it is time you start thinking about it. You don't need a backyard the size of Southfork to create an efficient, fun outdoor kitchen of your very own.
Creating Dynamic Window Coverings Without Breaking the Budget
When creating dynamic window coverings, it's important to choose carefully, because your window coverings will become the focal points of a well-decorated room. But choosing the right window treatments, at the right price, takes some thought about not only the look you're hoping to achieve, but also about the nature of the space itself.
Seven Essential Color Concepts for Designing Spaces
Understanding a few essential color concepts will help you design your living and work spaces more purposefully. Embrace the colors that work best for your specific activity and emotional support. Here are seven Design Psychology color basics:
Contractor Referral
"As a contractor with 16 years of experience and speaking on behalf of professional contractors. I want people to be aware of the warning signs that they may be dealing with the wrong contractor."
This Is Why People Should Consider Granite Countertops
Granite countertops are among the most beautiful things you can add to your kitchen. Kitchen countertops gain a beautiful glow from these pieces of art. They are made in nature and, once harvested by people, are refined into beautiful kitchen countertops that will add value to any kitchen. They come in many colors, colors that are made in nature and of true iridescent quality.
Popular Trends in Home Technology
As a former home automation installer and a former manufactures rep, I have
observed many trends. The following items are certainly the hotest trends this year
in home technology.
Vinyl Replacement Window Terminology
With so many homeowners in the market for more energy efficient windows and doors for their home, I thought I would use this week's article to cover the more common terms used to describe a window's ability to insulate your home from the elements. There is an organization called The National Fenestration Rating Council (NFRC). Their purpose is to test each window manufacturer's product to independently verify the ratings for each test administered. So, let's discuss each test and what it means.
Stair Railings Styles
The stair railing at home is more than a simple way to get from a floor to another. You can create an extension of your personal likes in decoration, with ornamental parts of wood, iron and other material easy to install that will increase the value of your home at the same time. If you think that the stair railing is one of the first tings that people see when they come in, you should think as well that, for building a new staircase or just a new remodelling, ask always for the advice and good service of a qualified person who will give you some good ideas for.
Window Dressing from the Outside Looking In
Window coverings are important to the overall look and feel of a room, of course, but when designing window treatments, don't forget to take into consideration what your overall design will look like from the outside of your home.
Use Air Filters and Common Sense for Allergy Relief
Do you suffer from allergies or asthma? If you are one of the millions of people that do, air filters and air purifiers provide much needed relief. Do you have smokers in the house? Air filters or air purifiers get rid of smoke and odor in your home. Different filters will accomplish different goals so you wouldn't purchase the same filter for both problems mentioned above. Before you buy, consider what kind of allergens or particles you are trying to remove. There are a variety of technologies used in room air cleaners including ionization, ozonation, electrostatic precipitation, ultraviolet light, mechanical filtration and odor absorption.
Basic Methods of Foundation Waterproofing
It is absolutely necessary to waterproof the foundation of your home. Foundation waterproofing is a critical step in maintaining your home's value and an important measure for preventing very serious damage. Usually done by professionals, foundation waterproofing is generally not recommended as a do-it-yourself project. Your home is likely your biggest investment, and foundation waterproofing is imperative in order to protect that investment. Ideally, foundation waterproofing takes place as the home is being built, but years of settling and water leakage or negligence on the part of the contractors often leaves the home's foundation unprotected.
|
