A 10" Air Cylinder in a 6" Space? |
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Perhaps none of our customers offer TECO Pneumatic more challenging application problems than the Lawrence Livermore National Lab. We are proud to have contributed in a small way to the National Ignition Facility at the Lab, which is now in operation as the largest laser in the world. If you get a chance to visit the Lab, you’ll recognize the NIF as the building about the size of a football stadium! Several years ago, design engineers at the Lab approached TECO Pneumatic with a difficult problem. The task called for a 10" bore cylinder operating at the maximum available air pressure over a 5 7/8" stroke. While there were some nonstandard mounting requirements, this presented no particular difficulty. The challenge was that the available space allowed for a cylinder with no more than 6" bore. Engineers correctly assume that force (the available air pressure) times area (the biggest bore cylinder that will fit) pretty much limits the work a cylinder can do. Fabco-Air offers a cataloged product for just this sort of difficult application.
Retracted As shown below, Fabco Multi-Power® air cylinders combine multiple pistons on a common cylinder shaft within a single cylinder body. Air moves between pistons by means of a unique air passage within the center shaft. One to four pistons and bores from 1 1/8" to 12" are available in this cylinder series. This creates a cylinder that can produce up to 44,000 pounds of force from standard shop air.
In the application at the Lab, TECO Pneumatic was able to provide a 6" bore, three-stage Fabco Multi-Power® air cylinder with a thrust force equivalent to that of a 10.2" bore single piston cylinder. It literally was a 10" cylinder in a 6" mounting space. Fabco-Air illustrates the operating principle of this cylinder with an excellent video. We also have cut-a-way cylinders that illustrate how this principle works in applications that call for clamping, pressing and punching as well as putting a big equivalent bore in a small space. Multi-Power® cylinders can eliminate the need for hydraulic systems, they save space, money and air. If the physics of air cylinders has you in a tight spot, contact TECO Pneumatic and explore the Multi-Power® option. Catalog information on Multi-Power® cylinders is available at the TECO website, www.tecopneumatic.com.
Kinetic Energy Management Options from NorgrenNorgren offers several interesting approaches to managing the energy in air cylinders at the end of stroke. In most motion control applications we first think about how to make cylinders go when, where and as fast as we want them to go. Stopping air cylinders is sometimes a neglected art, which we think of only when we see premature cylinder failures. Ecology piston seals provide significant energy absorption capacity, allowing for guaranteed and repeatable cushioning. On a 4" bore air cylinder with adjustable cushions that moves at 30 inches per second, Ecology piston seals will absorb a load of over 99 pounds. For complete information on the application of Ecology seals and information on how this data was derived, please see the Norgren section of the TECO Pneumatic web site.
In our last newsletter, we described how Norgren Ecology piston seals reduce the sound associated with end of stroke impact, providing up to 80% of the actual load stopping capacity. A conventional cylinder depends completely on the compressibility of air trapped within the cushion to do the stopping. The chart below shows the significant reduction in decibels of impact noise in 2" bore cylinders when the Ecology seal is employed.
Norgren’s Ultra Cushion design employs a unique one-piece seal that is allowed to "float" in both the linear and radial plane. This virtually eliminates problems associated with cushion misalignment and provides exceptionally fast "out of cushion" stroke reversal without the use of a mechanical check valve.
Decel-Air™cushioned cylinders from Norgren combine the Ecology piston seal and the Ultra Cushion with an extra long cushion sleeve and spear. The extra cushion length provides additional deceleration capacity that slows the cylinder’s moving mass to the point where the piston seal can provide the final cushioning. In the 4" bore cylinder example mentioned above, the stopping capacity with a Decel-Air™cushion would double to 198 pounds. In many applications a Decel-Air™cushion will replace a cylinder-mounted shock absorber.
If you have an application that calls for operating air cylinders at high speed, if you can hear your air cylinders beating themselves to death as you read this, please contact TECO Pneumatic. We would be happy to demonstrate Norgren’s innovative approaches to end of stroke energy management.
Easy Mounting Watson Miniature Air CylindersWatson Pneumatics offers a broad array of standard and custom made miniature air cylinders. At the center of their product range are cylinders with threaded bodies that mount quickly and easily without a special mounting bracket. The full OD thread allows for exact placement and mounting adjustability. These brass body, nickel plated cylinders are available in bores of 1/4", 3/8" and 1/2" and with strokes to 1/2". A non-rotating rod is available on the two larger bore sizes. Although small, these cylinders are very tough; the 660 bronze rod bearing is at least twice as long as the rod diameter.
In addition, Watson offers as standard products front and rear base mounted cylinders, rectangular body flat mount cylinders, miniature back-to-back cylinders and threaded nose mount cylinders.
Watson also makes excellent right angle flow controls, needle valves and check valves in 1/8", 1/4" and 3/8" NPT ports. Both the flow controls and check valves combine bubble tight sealing with 2-PSI crack pressure and generous reverse flow volume. Pressure drop and flow information along with detailed specifications are available at the Watson Pneumatics section of the TECO Pneumatic web site, www.tecopneumatic.com. If you need a lot of air cylinder in a small package, please ask your TECO sales representative about Watson miniature air cylinders. A New Tool for Specifying Position SensorsNow you can employ a powerful new tool to help specify Baumer Electric position sensors and rotary encoders. The site is easily accessible through the TECO Pneumatic web site, www.tecopneumatic.com. From our home page, click on "Our Suppliers," and "Baumer Electric." Then click on "Go to the Baumer website," and "Database." You can then select the category of sensor you need on a pull down menu (for instance, "Capacitive Sensors") and enter the parameters for your application. By inputting your application requirements and specifications, you can use the Baumer search engine to select the sensor or encoder product that suits your needs. The vast world of position sensors just became easier to navigate! We now have on hand an excellent new sensor catalog from Baumer. The new catalog includes a wide array of new sensors. Among them are:
diffuse laser sensors, page 2-2.28.
Please check it out on our website or ask your TECO salesperson for a copy.
Summer Thoughts...Quarterly thoughts have been part of the TECO newsletter since its inception in 1990. A compilation of more than 375 of these items is now available to you at our website, www.tecopneumatic.com. Please visit our website and check out the range of information available to you there, along many thoughts like the following:
Final ThoughtsThanks to each of you who stopped at the TECO Pneumatic booth at the Semicon Show last month. The show was, as always a chance to see what is new in this important market. Our colleague Dave McArthur has reworked both the TECO Pneumatic web site and our catalog on disc. We are very proud of both these resources. The TECO website (www.tecopneumatic.com) is always the best place to get up to date information on the products we supply and includes links to almost all our manufacturers. It also contains many past issues of this newsletter along with a compilation of more than 300 of our quarterly thoughts, cross referenced by author. Please do visit the website and let your TECO representative know if you would like to have a new updated CD catalog.
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TECO
Pneumatic Inc., Box 1809, Pleasanton, CA 94566 |
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