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You are here: opti-pack > B1: Measurement of Fragility to Shocks

B1: Measurement of Fragility to Shocks

It is important to understand the forces damaging the products. To explain the theory we here use a model product – a cabinet with parts mounted on a plate welded to the side of the cabinet. In this model the forces come as shocks from the bottom.

Shock - Produkt

A drop of 20 cm against a hard floor parallel to the side results in a 200-800 g shock at the cabinet. Let us study the forces of such a shock.

The shock works up in the walls of the cabinet. When passing the mounting plate with the components, the mass of the components creates stresses in the plate with a critical point/area in the connection between the cabinet and the plate. Before damaging the product, two conditions have to be fulfilled

  • The forces shall be higher than max. torque for the plate or cabinet.
  • The energy in the shock shall be high enough (short shocks with a high peak will not always have enough energy to make damage)

 

High shock – short time

OK

 

High shock – long time

Damage

 

Low shock – short time

OK

 

Low shock – long time

OK

 

The difference between short and long time is between 1-10 msec.