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BALL SLIDES

Del-Tron Ball Slides

®

6 Reasons to chooseDel-Tron Ball Slides

Load Ratings and Life Estimates ®
The rated load capacity of Del-Tron ball slidesmay be a mass load on a horizontal slide,or a force load normal to the mounting surface in any position. The rated load must be centered and distributed over the slide, andthe base must be fully supported on a flatmounting surface so that the ball slide does not act as a beam subject to concentrated or distributed bending forces. Loads supported by protruding arms reduce accuracy and load capacity by acting as levers or ratio arms, and should be avoided even when load forces are small.When used at the rated load capacity andmoderate speeds, a life of 10 million inches of travel can be expected.The expected life at one half the rated load is 100 million inches. ® Friction and Lubrication The coefficient of friction is lower for linear ball bearings than for rotary bearings, where the peripheral track is shorter on the inner race than on the outer race, causing the ball to skid on one or the other. The balls run exactly equal distances on the pair of tracksin linear bearings, permitting the ball to runwithout friction, wear, or skidding at any preload.The typical coefficient of friction for Del-Tron ball slides is 0.003.Lubrication is recommended for speedsabove 1800 inches/min, and is advisable at lower speeds where high loads are applied in continuous duty applications. 1. Factory preload adjustment preventssideplay and backlash.2. Lightweight aluminum carriage andbase with high load capacity.3. Built-in holes simplify installationand component mounting.4. Steel shafts, ground over the entirelength, reduce coefficient of friction to 0.003.5. Long life, self cleaning ball bearingneeds no lubrication.6. Mounting surfaces, parallel to theline of motion, provide straight line accuracy to 0.0005
® Mounting and Accuracy The mounting surfaces of the ball slide are machined flat and smooth, and parallel to each other and the line of motion. They must be mounted on smooth, flat supports that will not deflect under load. Especially with longslides of small cross section, binding may becaused by distortion of the bottom member when mounted on irregular surfaces. If so, round shims or spacers may be placed over the mounting screws to raise the slide above the surface asperities. Bedding in epoxy resin is also recommended.The specified accuracy for all standard Del-Tron ball slides is .0005inch/inch of travel.This is measured by comparison of the line of travel to a master straight edge, using a gage or indicator mounted on the slide. ″ / ″ of travel.
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