Jun 1, 2007 12:00 PM

Call it what you will — resonance, looseness, vibration, shock load, backlash, imbalance, noise, or strain cycles — none of it is good for machinery and equipment, leading to premature aging, unsafe operating conditions, and errors. Consider the following expert tips and tools for dealing with vibration and its noisy cousins.

Shock absorbers

MC 150H3, 225H3, and 600H3 industrial shock absorbers offer weight ratings from 400 to 10,000 lb. to decelerate loads, prevent impact damage, increase cycle speeds, and damp noise; ideal for heavy loads at low speeds.

Ace Controls Inc.
www.acecontrols.com

Oldham and jaw couplings

Oldham couplings and zero-backlash jaw couplings with standard keyways are now available as stock items. Keyways increase the coupling's torque capacity, useful in applications prone to shock loads caused by sudden stops and starts.

Ruland Manufacturing Co. Inc.
www.ruland.com

Resonance dampers

NEMA 17 dampers are durable and easily mounted to NEMA 17 stepmotors. As motors step, inertia makes the rotor oscillate in its new position, which can contribute to erratic system motion. Adding a damper to the motor shaft reduces the oscillations.

Lin Engineering
www.linengineering.com

Self-lubricating gears

Cast-in metal core gears use gear-life calculations in a one-piece gear design for lubrication-free, high-torque transmission in applications where shock, vibration, and frequent start/stop cycles are present.

Intech Corp.
www.intechpower.com

DBO Ulist

•  Many vibration issues are easily solved if caught early in the design cycle
•  Vibration is detrimental to bearing life and machine performance

•  Vibration takes many forms and varies with frequency; three main types are linear, bending, and torsional

•  Measuring vibration is essential to controlling it

•  When choosing a vibration sensor, think about measuring displacement, velocity, and/or acceleration

•  Apply vibration isolation and damping treatments close to the source

•  If vibration isolation isn't practical, use structural damping to reduce structure-to-structure vibration transmission

•  Apply damping treatments to areas undergoing high dynamic strain

•  System looseness creates problems with mating components; avoid it

•  Consider tuned damping to increase the performance of high-speed, position-critical motion systems

•  Misalignment is one of the biggest factors leading to excessive vibration

•  Use couplings to eliminate or minimize vibration

•  Servo-insert couplings with polyurethane spiders between coupling hubs help damp vibration

•  Zero-backlash couplings deal with imbalance and isolate shock loads

•  Safety couplings and torque limiters can prevent unexpected shock load from transmitting down the drive chain