Cylinder Machines

Some Knowledge about Rotary Actuators

The term rotary actuator might not be something that you think about every day, but it is something that you take advantage of every day, in both direct and indirect ways. So what are rotary actuators?

 

In some ways, you can think about the actuator in the same way you would think about an arm, finger, hand, or leg. By definition, an actuator is operated by a source of energy that is then converted into motion. In the case of an industrial application, the source of energy is usually electrical current. In the case of your finger, hand, arm, or leg, it’s much different. However, in both situations the actuator allows the mechanism – be it hand or robotic part picker – to interact with the environment.

 

Without actuators life would be incredibly different. Have you ever tried to live a day without the use of your arms? Or maybe you do make do without the use of a limb. In the same way, the industrial world relies on actuators to make many manufacturing processes possible. Without actuators, many of the products we expect to be readily available would be much scarcer.

 

In simple applications, actuators are predominantly mechanical, providing linear motion in a single direction to provide rotation or movement as needed. While most actuators tend to be powered electrically, many others are also powered with hydraulics or pneumatics. This article will focus on the usage and application of pneumatic rotary actuators.

 

Pneumatic rotary actuators are very low maintenance units available in different configurations to suit varying applications. Two of the primary configurations often considered for pneumatic rotary actuators include either a double crank mechanism for modulating control or a scotch yoke mechanism that enables on/off control.

 

A double crank mechanism is exactly what it sounds like, two cranks working in conjunction to provide the needed rotational movement. On the other hand, a Scotch yoke converts the linear motion of a slider into rotational motion by combining a piston with a sliding yoke that then interacts with a pin on whatever part is rotated. This newer and more advanced system allows for fewer moving parts and smoother operation.

 

Today, pneumatic rotary actuators are used in a number of industries such as petrochemical, food, mining, manufacturing, power generation, paper, and more. Applications range in magnitude from simple machinery to large-scale engineering applications like sluice gates and dams. Because of the diverse and widespread use of rotary actuators the size, power, and possible speeds capable are as varied as the industries they are utilized in.

 

Autogrip Machinery Co., Ltd. is a rotary actuators manufacturer in Taiwan. We specialize in manufacturing power chucks, special purpose power chucks, collet chucks, stationary chucks, facing heads, rotary cylinders, rotary valve/rotary joint and parts/accessories. If you need further details about Autogrip and our products, welcome to visit our website and feel free to contact us!

 

Article Source: http://EzineArticles.com/expert/Hank_Moon/1260388

 

Article Source: http://EzineArticles.com/7118819

 

Share

Comments Off on Some Knowledge about Rotary Actuators

How Do Hydraulic Cylinders Work?

Hydraulic cylinders are remarkably simple, nothing more than a piece of iron tube, a steel rod and other bits holding it all together, yet so incredibly powerful. They are truly the workhorse of our world, providing the muscle that moves & forms the earth & structures around us. But do you know how hydraulic cylinder works? How does something so simple & relatively small do such an amazing amount of work?

 

It’s an old principle. The amount of pressure exerted on anything increases in force as the area of the object increases. If you put 1 pound of pressure on a 1 inch object, you get 1 pound of pressure. If you put 1 pound of pressure on 2 inches, you get 2 pounds per square inch. The formula for this is Area X PSI (Pounds per square inch) = Force.

 

So, the larger the cylinder piston, the more lifting (or pushing) it can do.

 

The PISTON is the part inside the cylinder that the fluid pushes against. The diameter of the cylinder piston is called the BORE. The larger bore cylinders have more force exerted upon them, therefore a higher lifting capacity. The hydraulic fluid is contained by the piston seal. That’s why a cylinder with a defective piston seal will not lift as much as it should. Even though the cylinder may not be leaking on the outside, a damaged piston seal will allow oil to bypass the piston, so the pressure will not reach the required level to do the lifting that is expected.

 

The ROD (or shaft) of the cylinder is the part that travels through the GLAND (or head) of the cylinder and attaches the piston to the end fitting (usually a clevis, cross-tube or tang). The diameter & hardness of the rod are important because the further out it is extended, the more “side-load” is exerted on it, increasing the risk of bending. That’s why higher pressure cylinders have stronger rods, so that if they are lifting a heavier load they are less likely to bend. This is commonly know in the industry as COLUMN LOAD. Welded hydraulic cylinders typically have an “induction-hardened” rod, which is much harder to bend.

 

The STROKE is the difference between the fully retracted length and the fully extended length of the rod. This is the total travel of the cylinder. This is one of the key measurements of a cylinder, but also on that is most commonly confused.

 

The GLAND (or head) of the cylinder is part of the cylinder that the piston rod travels through. The rod seal is contained inside the gland and is the most common cause of cylinder leaks, since it is exposed to the elements and is in charge of removing debris from the rod as it retracts into the body of the cylinder.

 

The BUTT is the base (or cap) of the cylinder. On tie-rod cylinders it is a separate piece that also has an o-ring seal, which is a point of potential leaks. On welded cylinders, it is welded to the hydraulic cylinder tube, so no seal is required.

 

Some cylinders are made single-acting (push under pressure, gravity return), but most are double-acting which means that the piston is under pressure on both the push and pull side of the cycle. Double-acting cylinders can be easily used in single-acting applications, because a breather fitting can be fitted in the unused port to allow air to be displaced on that side.

 

So, that’s how it works in a nutshell. As stated previously, its such an amazing amount of work executed by an elegantly simple process that is so often overlooked. Hydraulic cylinders are truly a design masterpiece and will not soon be replaced by any other tool due to their power, efficiency and durability.

 

Visit the hydraulic cylinders page at International Hydraulics’ Website for information, how-to’s & more. International Hydraulics supplies hydraulic components for major industries throughout the US from their facilities in Roanoke, VA.

 

Article Source: http://EzineArticles.com/expert/L._Kelly/1273329
Article Source: http://EzineArticles.com/6857643

Share

Comments Off on How Do Hydraulic Cylinders Work?

Pneumatic Cylinders and Their Types

Pneumatic cylinders are a type of mechanical appliance that makes use of power generated from compressed gas to create a force in reciprocating linear motion. They are also sometimes referred to as air cylinders, as in “pneuma” meaning air. Much like in hydraulic cylinders, a force is exerted into the piston which propels it towards the desired direction. In these devices, the piston is actually a cylinder or a disc, and the force developed by it is transferred by the piston rod to the object that is to be moved. Pneumatics is occasionally preferred by some engineers as they are much cleaner, quieter and doesn’t require much space for the storage of fluids.

Depending on the purpose for which they are used, these cylinders come in a variety of shapes and sizes. This is also applicable to the kind of material used to construct these cylinders. They can be made out of steel, stainless steel, aluminum and nickel-plated brass. Choice of materials is mostly dictated by the humidity, temperature, specific stroke length and the amount of loads. The body constructions in which these cylinders are available include the following:

  • Flanged-type cylinders: In this type, fixed flanges are present at the ends of the cylinder.
  • Tie rod cylinders: This is the most common form of cylinder construction and can be used for a wide variety of loads. It has also been proven as the safest form to work with.
  • Threaded end cylinders: In this type, the ends are screwed to the tube body. However, reduced material may lead to weakening of the tube and introduce thread concentricity issues to the system.
  • One-piece welded cylinders: In this type, the ends are crimped or welded to the tube. Although these are inexpensive, they make a cylinder non-serviceable.

There are different types of pneumatic cylinders in use in a wide variety of industrial and commercial arenas. Some of them have been discussed below in brief.

Single-acting cylinders

Single-acting cylinders or SAC makes use of pressure that results from compressed air to create a unidirectional driving force, usually towards the outside, and a springing motion to get back to its original position. In most cases, these cylinders have very limited extension because of the space taken up by the compressed spring. Another flip side of single-acting cylinders is that a portion of the force is always lost as it attempts to push itself against the spring.

Double-acting cylinders

Double-acting cylinders or DAC makes use of air pressure to move in extend as well as retract strokes. These cylinders are comprised of two ports which lets the air in; one for instroke and the other one for outstroke. The stroke length for double-acting cylinders is not limited. This type of cylinder is not however without its flaws. The piston rod may buckle and bend over time and precise calculations should be carried out before working with these cylinders.

Telescoping cylinders

Telescoping cylinders or telescopic cylinders come in either single-acting modes or double-acting modes. It makes use of a piston rod that is placed within a few hollow stages of ascending diameters. Once activated, the piston rod along with each of the successive stages “telescopes” out like a separate segmented piston. This type of pneumatic cylinder design allows for much longer strokes than what can be achieved by a single-stage cylinder of same retracted or collapsed length. However, its segmented piston design increases the chances for piston flexion. For this reason, these type of telescoping cylinders are mainly reserved for applications where its piston has to go through minimal side loading.

 

Article Source: http://EzineArticles.com/8640058

Share

Comments Off on Pneumatic Cylinders and Their Types

Cylinder Head Machine Manufacturer

Chin Minn has been a cylinder head machines manufacturer for more than 20 years. Our machine products including roll forming machine, automatic assembly machines and special purpose machine, cylinder honing machine, cylinder boring machine etc. Our team has always strived to meet the highest level of customer satisfaction and we are committed to service our clients through continuously evolving to meet the ever changing demands of the manufacturing industry. If you are interested in our products, please feel free to contact us.

Special Purpose Machine

Special Purpose Machine

CHIN MIN INDUSTRIES CO., LTD.
Address: No.3-3,Shiow Chung Street, Shiow Shoel Hsiang, Chang-Hua, Hsien 504, Taiwan
Tel: +886-4-7699101
Fax: +886-4-7681010
E-Mail: chin.minn@msa.hinet.net

 

Share

Comments Off on Cylinder Head Machine Manufacturer