Shock Tech Isolation Efficiency Graph

ISOLATION

PERCENTAGE

Solutions for Shock, Vibration & Noise Control

GRAPH

The SHOCK TECH Isolation Percentage Graph is a three (3) axis plotting tool that can be used to quickly determine percentage of isolation by comparing Forcing Frequency (Ff) to Natural Frequency (Fn) system values.

· The Efficiency Graph tool is limited to a single degree of freedom (SDoF) and single dynamic input of any kinematic relationship for a mass in steady state sinusoidal motion. It also reveals to the user that the Fn needs to be at least one (1) full octave away from the Ff to intersect at the 70% isolation range line which is a common rule of thumb baseline for start of efficient isolation.

These web site examples are shown as indicators to determine what a suspension system will need to remain in the isolation range as well as provide a guide for selecting isolator Fn that is not too soft as to be impractical. If you are not sure that the graph is yielding percentage results that you would like to have in your system, contact a SHOCK TECH Applications Engineer to help you with your solution and advice as to what limitations their may be with geometry, size the mount, materials or stability for your system values. To download a clean 'A' size (8.5in x 11in) PDF of the Isolation Percentage Graph, click on any of the graphs below to print or save it from the new browser window for your use.

The Isolation Percentage Graph tool is for use as a general guide only for determining what mount performance parameters might be needed for any given application. It is not a guarantee of exact requirements or performance of any dynamic suspension system. SHOCK TECH always recommends testing to validate any mount selection's performance for all applications.

Sinusoidal Vibration Example in Amplification:
Forcing Frequency (Ff) = 30Hz
System Natural Frequency (Ff) = 25Hz
Problem: Determine if System is in Isolation Range.
Step 1: Locate Ff along horizontal line line; = 30Hz (1800CPM)
Step 2: Locate Fn along the vertical line; = 25Hz (1500CPM)
Step 3: Read the Percent Isolation from the Percent Isolation values (rotated 45° clockwise/to the right from vertical); = Amplification Range

Sinusoidal Vibration Example in Isolation:
Forcing Frequency (Ff) = 30Hz
System Natural Frequency (Ff) = 15Hz
Problem: Determine if System is in Isolation Range.
Step 1: Locate Ff along horizontal line line; = 30Hz (1800CPM)
Step 2: Locate Fn along the vertical line; = 15Hz (900CPM)
Step 3: Read the Percent Isolation from the Percent Isolation values (rotated 45° clockwise/to the right from vertical); = 70% Isolation