Linear Slides

Specifications subject to change without notice or incurring obligations Page 6 FABCO-AIR Linear Slides 1-12-10 Factor 4 – continued Linear Ball Bearing Loading and Life Expectancy Many slide applications involve an overhung load applied to the end of the guide shaft. In almost all of these cases, the slide's load capacity is determined by the strength of the guide shaft and its ability to resist bending. Linear ball bearings are not the limitation because their load capaci- ties dramatically exceed the bending strength of the guide shafts. Linear Ball Bearing Load Capacities For Shaft Diameters of Rolling Load Ratings .250" . . . . . . . . . . . . . . . . 60 lbs each bearing .375" . . . . . . . . . . . . . . . . 64 lbs each bearing .500" . . . . . . . . . . . . . . . . 177 lbs each bearing .625" . . . . . . . . . . . . . . . . 272 lbs each bearing .750" . . . . . . . . . . . . . . . . 300 lbs each bearing 1.000" . . . . . . . . . . . . . . . . 410 lbs each bearing 1.500" . . . . . . . . . . . . . . . . 900 lbs each bearing Example: from the load sizing guide found on page 45, a model EZ1000 slide with 2.0" stroke has a recommended overhung load of 200 pounds (produces .005" max. toolbar deflection or less). This load is supported by two lin- ear bearings rated at 410 lbs each, 820 lbs total - which translates to a “safety factor” of more than 4 to 1! For a 20" stroke with the same .005" deflection, the load sizing guide gives a load recommendation of 4 pounds – a factor of over 200 to 1! Linear ball bearings provide precise “no play” motion and long life is assured because it is loaded only to a small frac- tion of its capacity. Life expectancy is 3 million to over 10 million cycles. This general cycle life can be predicted regardless of its stroke because the linear ball bearing is being so lightly loaded, compared to its rated capacity. Cycle life is determined as much by the number of “ball circuit reversals” as any other factor, including inches of total shaft travel. Loading of Sleeve Bearings Sleeve type bearings offer simplicity and low cost. They are ideal for moderate overhung loads, and can easily handle high loads in moderate speed carriage load applica- tions. Fabco-Air's superior Duralon ® bearing offers increased performance over other sleeve bearing materials. Self lubricating, low friction Duralon ® is a composite of Teflon ® /Dacron ® fabric liner bonded to filament-wound, high strength fiberglass and epoxy shell. Duralon ® is resistant to corrosion, moisture, and temperature to 325° F. It has outstanding physical properties, very low friction, and will not gall or score guide shaft material. Duralon ® bearings are provided as standard on “GB” and “L & S” Series slides, and are available as an optional substitution (specify option code “X”) on all other Fabco- Air linear slides. Rulon ® bearings can be substituted for linear ball bearings by specifying option code “W”. These bearings have an anodized aluminum shell with a Rulon ® liner, and are available for users preferring this type of bearing material. Guide Shaft Material Selection The “GB” and “L & S” series slides are provided standard with pre-chrome plated stainless steel shafting. This material is supplied on other slides when option “X” (Duralon ® ) or option “W” (Rulon ® ) is specified. Slides with linear ball bearings are supplied with case hardened and ground steel (1045) shafting (shaft surface acts as inner race for the linear ball bearings). “SE” series uses a slightly larger tolerance material than “EZ” and “TS” slides, to provide a controlled pre-load for “no-play” mo- tion. When option “Z”, stainless steel shafting, is specified for use with linear ball bearings, a 440C case hardened and ground stainless material is supplied, ground to the same tolerance as 1045 shaft would be for that slide model. Note: 1045 shafting is hardened to 60-65 R c, while 440C stainless is hardened to 52-56 R c. Higher loaded slides may have a slight shaft life expectancy reduction with the 440C material. Pancake ® , Square-1 ® , & Multi-Power ® are registered trademarks of FABCO-AIR Inc. Global Series™ is a trademark of FABCO-AIR Inc. Teflon ® & Dacron ® are registered trademarks of DuPont. Duralon ® is a registered trademark of Rexnord. Rulon ® is a registered trademark of Furon APD Dixon

RkJQdWJsaXNoZXIy NDI5NDE=