Then the engineer defines the excitation and natural system frequencies and calculates maximum isolator stiffness. First the designer defines the system into which the isolator is going - by supported load, number of isolators to support the load, and whether the application will see just compression or rolling. Wire-rope isolator selection is a three-step process. WIRE ROPE ISOLATOR FULLJust remember that stiffness values are for full-loop versions - and reduced-loop versions have stiffnesses that are the unit’s standard stiffness times the ratio of actual loops to the standard number of full loops. Published values average vibration stiffness and shock-stiffness values for use in equations to predict system performance. However, note that wire-rope isolators exhibit non-linear stiffness so small deflections (usually associated with vibration isolation) induce different spring rates than large shock deflections. Another option for high-fatigue applications is a “bellmouth” having mount bars with radii manufactured into the wire-rope hole edges. Its wire-rope isolators come in two-loop versions all the way to full loop numbers. Options are through-hole, countersunk, and threaded bars for mounting. Wire-rope isolators cost effective in long run + protect machine frames Click To Tweet WIRE ROPE ISOLATOR INSTALLOne benefit to the compact versions is that they install with just a single point of attachment at each interface. The samples reviewed in the above video include both traditional bar and compact isolators - these square ones. An array of mounting options and sizes exist with versions to meet commercial, industrial, and defense including MIL standards. Part of some helical isolator designs is a patented crimp pattern. But adding wire-rope isolators is cost effective - and done upfront, it protects machine welds and brackets from fatigue. It’s expensive to keep equipment perfectly balanced, and it’s inefficient to add braces. Corrosion-resistant metal construction gives the isolators a design unaffected by temperature extremes, ozone, chemicals, oils, and abrasives. In some cases, the split bars clamp onto the cables. Standard wire-rope isolators from some manufacturers are made of stranded stainless-steel cable that threads through aluminum-alloy retaining bars. Wire rope isolators do this and attenuate shock too. Vibrations damage machines and electronics, so designs often incorporate wire-rope isolators, air springs, or elastomers - but elastomers only attenuate noise and vibration levels. In the video below, I join my colleague Mary Gannon to review several wire-rope isolators from ITT Enidine and where they make the most sense. But adding wire-rope isolators is a cost-effective way to address vibration - and when done upfront, it can save machine structures from fatigue. It’s expensive to keep equipment perfectly balanced, and it’s often inefficient to add structural reinforcements.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |