Earthquake, vibration and shockVerification of earthquake resistance is a well-developed working area for SP, which has a broad and substantial experience of the work. Much of this type of testing is used to assist export industries and the Swedish nuclear power plants stations. Typical items tested include electrical equipment, electronics cubicles with control and instrumentation equipment, and telecommunications equipment. We perform earthquake resistance tests in accordance with most international standards.
Testing is carried out on a two-axis servo-hydraulic shake table, of sufficient power to excite large and heavy items. The table can apply vertical and horizontal accelerations simultaneously, together with rotation up to a frequency of about 80 Hz, independently of each other. For larger objects, or those more then 3 m high, we use a single-axis shake table that can excite objects up to 3 x 3 x 6 m up to a frequency of about 50 Hz in the horizontal direction.
Our servo-hydraulic shake table can also be used for simulating vibration in vehicles. We carry out vibration testing not only of transported goods, but also of equipment that is secured to or in vehicle. The equipment is suitable for testing large, heavy items at low and moderate frequencies, while smaller and lighter items can be tested at high frequencies on SP's electromagnetic vibration rigs.
Our two-axis vibration table can be used for shock testing, which can half sine shock pulses with durations exceeding 20 ms and accelerations up to about 5 g. For shock testing with pulses os shorter durations, SPs electromagnetic vibrator is in most cases the most suitable equipment.
A crash sledge is available for extremely long-duration shock pulses. We can produce horizontal shock pulses with acceleration levels up to 25-50 g with durations of the order of 50 ms.