Estimating Shock Severity
The recently issued specification ANSI/ASA S2.62-2009, Shock Test Requirements for Equipment in a Rugged Shock Environment, specifies shock severity levels according to the plateau level on the PVSS plotted on 4CP, (pseudo velocity shock spectrum plotted on four coordinate paper). The levels run from 1 - 10 meters per second or 40 to 400 ips. These ANSI levels provide an example of how to identify shock severity. Examples are plotted of both PVSSs and SRSs divided by 2 pi f, to form an acceleration PVSS or APVSS on 4CP. These show that the plateau of the APVSS is the same as the PVSS. Thus published SRSs can be evaluated with constant velocity lines drawn on the SRS which also show the severe frequency range. The paper shows severity levels of many SRSs. Several pyroshock references that refer to plateau severities of 50 ips as very mild, 100 ips as moderate, and 300 ips as very severe are examples.
KeywordsExplosive Assure Sine Hunt Editing
Unable to display preview. Download preview PDF.
- 1.Hunt, F. V. “Stress and Strain Limits on the Attainable Velocity in Mechanical Vibration;” J. Acoustical Soc. Am. Vol 32, no. 9, Sept 1960, pp 1123-1128.Google Scholar
- 2.Gaberson, H. A. and Chalmers, R. H., “Modal Velocity as a Criterion of Shock Severity,” Shock and Vibration Bulletin 40, Part 2, Dec 1969, pp 31-49.Google Scholar
- 3.Gaberson, H. A,, "Pseudo Velocity Shock Spectrum Rules for Analysis of Mechanical Shock"; IMAC XXV, Orlando, FL; Society of Experimental Mechanics; Bethel, CT, http://www.sem.org; Feb 2007; p 367
- 4.Gaberson, H. A, "Pseudo Velocity Shock Spectrum Rules and Concepts", Proceeding of the Annual Meeting of the Mechanical Failure Prevention Technology Society [http://www,mfpt.org] Apr 07
- 5.Gaberson, H.A. SAVIAC Training lecture notes, Part 2, available on http://www.SAVIAC.org/ under Shock and Vibration Symposium, Training. 2008, 2007, etc.
- 6.Gaberson, H.A., D. Pal, and R.S. Chapler, "Shock Severity Measurement for Facilities Equipment" 69th Shock and Vibration Symposium, October 1998; published in the meeting proceedings spring of 1999.Google Scholar
- 7.7.. Piersol, Allan G., "Preliminary Design Procedures for Equipment Exposed to Random Vibration Environments", J. of the IEST, Winter 2001, pp 23-27Google Scholar
- 8.ANSI Equipment ruggedness specification ANSI/ASA S2.62-2009: Shock Test Requirements for Equipment in a Rugged Shock Environment.Google Scholar
- 9.STANAG 4549, NATO Standarization Agreement (STANAG) Testing of Surface Ship Equipment of Shock Testing Machines, 2008Google Scholar
- 10.10.. Eubanks, R.A. and Juskie, B.R., “Shock Hardening of Equipment,” Shock and Vibration Bulletin 32, Part III, 1963, pp 23-73Google Scholar
- 11.Gaberson, H.A., and Eubanks, Ph.D., S.E.,R.A., "Simplified Shock Design for Equipment Installation," NCEL Technical Note, N-1622, March 1982 ADA AD114331.Google Scholar
- 12.Morse, Robert, presentation at Spacecraft & Launch Vehicle Dynamics Environments Workshop Program - June 20, 2000, Aerospace Corporation, El Segundo, CAGoogle Scholar
- 13.Walton, W. Scott; "Ballistic Shock Fundamentals"; Shock and Vibration Symposium; 2001Google Scholar
- 14.Kurng Y. Chang, "Pyrotechnic Devices, Shock Levels And Their Applications", Pyroshock Seminar, ICSV9, July 8 - 11,2002, Orlando, FL, Slide 18aGoogle Scholar
- 15.Bateman, Vesta I. "Are All Pyroshock Simulations with Resonant Fixtures the Same?", 79th Shock and Vibration Symposium, Oct 2008, Orlando, FLGoogle Scholar
- 16.17.. Gaberson, H. A, "Use of Damping in Pseudo Velocity Shock Analysis", IMAC XXVI, Orlando, FL; Society of Experimental Mechanics; Bethel, CT, http://www.sem.org; Feb 2008
- 17."Harris' Shock and Vibration Handbook" 5th Ed. 2002, Ed by Cyril M. Harris and Allan G. Piersol, p 1.20Google Scholar