Plain bearings stand up to the earthquake test
Simplicity® linear bearings have been installed in an earthquake simulation machine developed by the Washington University Structural Control and Earthquake Engineering Lab (WUSCEEL) in St. Louis, Missouri. Due to their ability to tolerate intense shock and vibration without fretting and require no added grease or oil, the PBC Linear plane bearings were perfectly suited to handle the job.
Intense shock vibration is an obvious pre-requisite to study the impact of earthquakes and structure analysis. To recapture the conditions of an earthquake, researchers construct what is typically referred to as a “shock table”. A shock table is a machine that simulates the conditions of an earthquake. The entire structure weighs up to 850 lbs, and when vibrating can exert 3-4 g’s of force on the bearings and shafting.
The PBC Linear solution
Simplicity linear plane bearings are designed to last in the toughest environments; including heavy loads and short strokes. With no rolling elements, the linear plane bearings contain no moving parts to fret and seize up; this completely eliminates the potential for catastrophic failure. Their proprietary FrelonGold® liner also enhances load capacities and dampens shock vibration—making the Simplicity line an attractive candidate to anyone seeking to study earthquakes or other heavy load applications. Combined with PBC Linear ceramic coated shafting, the Simplicity plane bearings provided smooth, quiet and long-lasting linear motion even in the cruel environment created by the shock table.
The WUSCEEL shock table is used to test for a wide range of structural analysis: bridge and building stability research, fragility curves and vibration control of aero systems. Any structure or material that could be affected by an earthquake or other high vibration surroundings is put to the test on these tables. These experiments prompted the researches to discover new ways to build earthquake resistant bridges, more reliable air planes, and stronger buildings.