Linear guide systems - Nadella - #10

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table.main {} tr.row {} td.cell {} div.block {} div.paragraph {} .font0 { font:8.00pt "Arial", sans-serif; } .font1 { font:10.00pt "Arial", sans-serif; } .font2 { font:11.00pt "Arial", sans-serif; } .font3 { font:23.00pt "Arial", sans-serif; } Technical features Lubrication Bearing lubrication All the guide rollers, except for the FRN..EI, based on needle bearings, are equipped with long life lubricated bearings. This means that the grease inside the bearing is enough for the entire life of the roller guide. The roller guide type FRN..EI, with needle bearings, accommodates the re-lubrication of the bearings. Rail lubrication Rails must be lubricated. This allows reducing the friction, to reach the calculated lifetime of the system and to work at high speed. No or insufficient lubrication will cause rapid deterioration. The typical signal of tribocorrosion is the presence of a red/dark oxide and rapid wearing of the rail and guide rollers. The lubrication of the rail, the working environment and the load must be considered all together for a correct estimation of the lifetime of the guide system. Generally speaking, for application with low duty frequency, a periodic relubrication with a grease or with a viscous oil will sufficiently maintain the lubrication film. The re-lubrication interval depends on the application and must always be tested in the real working conditions. In a system with ground rails and short stroke without lubricators, you can consider a re-lubrication interval every 100,000 cycles. Increasing the load, speed or stroke, or using an under sized bearing will increase lubrication demand and result in a shorter lubrication interval. For a constant lubrication we suggest the use of felt lubricators to ensure a constant layer of lubricant between guide rollers and raceways. Felt lubricators enlarge the lubrication interval more than ten times. The recommended lubricants are greases and oil for bearings, linear rails or chains, with a high viscosity of the basic oil and with EP additives, in order to separate the metallic surfaces even with low speed. Assembly instructions Guide rollers The eccentric guide rollers allows the preload or clearance of the carriage to be adjusted independently of the guide roller mounting hole positioning tolerance or the distance between the rails. Recommended mounting hole tolerance is H7. When adjusting the eccentric guide roller care has to be taken to avoid excessive preload. Excessive preload can reduce the life of the linear system. Set the preload turning the guide roller counterclockwise so that any movement caused by vibration will cause the nut to be tightened. Ensure the preload is not increased when tightening the nut. A simple way of setting a roller preload is as follows: 1 move the slider on the guide, holding the roller being adjusted with two fingers to prevent it from rotating 2 increase the preload by means of the wrench 3 repeat step 1 making sure the roller slides without rolling 4 when it is no longer possible to prevent roller rolling, slightly decrease the preload and fully tighten the lock nut, thereby setting the position of the eccentric. When correctly adjusted it is just possible to cause the guide roller to slip on the guide rail when a torque is applied to the roller. Guides For single guide rail type FS, FWS, DC and LM no special assembly instructions are necessary. For multiple parallel rails parallelism has to be checked to avoid guide rollers overload or excessive carriage play. When constant preload is required parallelism error has to be lower that 0.050 mm. Connection between the rail and the mounting surface has to be designed accordingly with the operating condition to ensure proper product positioning and functionality. The direction and intensity of the load, the number and strength of the screws, the geometry of mounting surfaces, use of pins or wedges have to be evaluated to fully utilize the linear guide load capacity. Carriages Carriages are supplied with concentric guide rollers nut tighten already. Eccentric guide rollers have to be set and tighten during final assembly operation by customer. 9