Crossed Roller Bearings Series Crossed Roller Bearings Series:

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1 Crossed Roller Bearings Series Crossed Roller Bearings Series: Proprietary 2V Grinding Technology 102

2 Crossed Roller Bearing Series: Overview High Precision Bearing Sets Proprietary 2V Grinding Technology Parker Bayside uses a proprietary 2V grinding technology designed to achieve accuracy levels that are twice as high as the industry average. In the first step of the 2V process, CNC grinders with specially developed wheel media grind the banking reference and mounting surfaces in the same sweep. In the second step, another CNC machine, with a different wheel media, grinds the V-shaped bearing surface in a soft force magnetic chuck and in strict reference to the banking surface. Pre-sized high-precision rollers and customdesigned roller retainer strips complete a bearing system unlike any other in the market. Step 1 of 2V grinding process When to Use: High Precision Short Travel up to 440mm High Carrying Load Zero Bearing Clearance Clearance When to Use: Applications: Electronic Assembly Fiber Optics Medical Pharmaceutical Semiconductor Step 2 of 2V grinding process 58 to 62 Rc Cross sectional view of a Crossed Roller Rail showing hardness values RC Series Sizes Raceway Lengths Load Carrying Capacity 138 Crossed Roller Bearings 3mm and 6mm 50mm to 700mm 2,180kg (4,806 lb)

3 Crossed Roller Bearing Series Rail Set Dimensions Part Roller Diameter A B C D E Number (mm) (in) (mm) (in) (mm) (in) (mm) (in) (mm) (in) (mm) (in) RC RC Part F G H J K M Number (mm) (in) (mm) (in) (mm) (in) (mm) (in) (mm) (in) RC M RC M Part Travel L # Holes # Max. Load Number in Rail Rollers (mm) (in) (mm) (in) (kg) (lb) RC RC RC RC RC RC RC RC ,044 RC ,161 RC ,278 RC ,452 RC RC ,202 RC ,444 RC ,918 RC ,160 RC ,200 2,645 RC ,310 2,888 RC ,520 3,351 RC ,740 3,836 RC ,960 4,321 RC ,180 4,806 RC ,960 4,321 RC ,180 4,806 (1) Max. Load is based on a set of rails which consist of 4 rails and 2 retainers. P.A.C.T. is a Patented Anti-Creep Technology that prevents roller migration in vertical and high-speed applications. This option is available in bearing sizes of 3mm and 6mm. To order P.A.C.T. call out P/N PP-001 as a separate line item on your order. See how to order for options.

4 Installation Guide Crossed Roller Bearing Installation Crossed Roller Bearings, when properly installed and preloaded, provide repeatable low-friction linear motion while eliminating side play. The opposed axes of the successive rollers create a line contact that allow crossed rollers to be mounted in any attitude. As compared to linear bearings using balls that have a point contact, crossed roller bearing line contacts have the ability to carry heavier loads (up to 10 times higher than ball bearings), obtain higher accuracy / repeatability and provide a smoother rolling motion approaching than that of an air bearing. The Crossed Roller Bearing line contact also eliminates the grooving or wearing problem associated with ball bearing point contact ensuring the integrity of your application over time. The following guidelines will help you install your bearing set. Mounting Surface of Your Bearing Set The most important issue in obtaining the highest accuracy and repeatability from your bearing set is the accuracy of its mounting surfaces. Special care should be taken to ensure the accuracy of parallelism and coparallelism of the mounting surfaces and their perpendicularity is to the highest tolerances. To obtain travel accuracy better than 1u / cm (0.0001" / ") your mounting surfaces should be equal or better than the following. B REFERENCE WALL A B.0001" A RAIL BED Preloading Bearings Bearing preloading is a process of eliminating any side and vertical play while at the same time being careful not to create any friction in your bearing set. The most common method to load your bearings is by applying even amounts of force against an adjustable rail with a set screw in order to obtain a smooth rolling motion and mechanical stiffness. Special care should be taken to ensure that the preload is evenly distributed over the full length of the raceway. This can be accomplished by using a torque wrench or an experienced hand. Depending on the amount of stiffness needed for your application and the rigidity of your mounting structure, preloads can vary from 2% to 25% of the maximum load of the bearing. At right is a common preload method, if your application requires an alternative method contact the factory for application assistance. 1. MOUNTING SURFACE 2. BANKING SURFACE 3.ADJUSTABLE RAIL 4. PRELOAD SCREW 5. MOUNTING SCREW

5 Crossed Roller Bearing Series Installation Guide Bearing Spacing The spacing of your bearing set will have an effect on the stiffness and performance of your assembly. A general rule of thumb is to have the distance of the contact length of your bearings strip set relative to the distance between bearing. While this relationship can vary, ideal conditions should provide for a 1.5 contact length (C) to 1 bearing distance (W). (C) CONTACT LENGTH (W) BEARING WIDTH Lubrication The low co-efficient of friction of crossed roller bearings (approx 0.003) means little lubrication is necessary for your bearing set. Lubrication is used more to protect against corrosion than wear. Often a single application of lubricant can last a lifetime. For applications that have special environmental considerations there are a number of alternative lubricants available. Contact the factory for special lubricant recommendations. Component set part numbers include the following: Crossed Roller Four rails, two roller strips and eight end screws. Double V Crossed Roller Two rails, one double V rail, two roller strips and six end stops.

6 How to order How to Order Order Numbering Example: RC 3 T 200 A 35 1 A B C D E F G A BEARING SERIES RC Crossed Roller E RETAINER MATERIAL (1) A - Steel B BEARING SIZE (2) 3 3 mm 6 6 mm F ROLLER COUNT Number of rollers C BEARING MATERIAL T S Tool Steel Stainless G OPTIONS 1 None 2 End Stops D Rail Length Bearing Size 3mm 6mm NOTES: (1) Contact factory for alternative retainers - Al, Brass and Plate (2) Available 3 mm only (3) Pact (anti-creep) per request How to Order Parker Bayside s Crossed Roller Series is supported by a worldwide network of offices and local distributors. Call for application engineering assistance or for the name of your local distributor. Information can also be obtained at or Specifications are subject to change without notice. 107