Westpak is certified to conduct product/package integrity testing to help guarantee successful delivery of products worldwide by any means of transportation.

Westpak is accredited to ISO/IEC 17025-2005, one of the most rigorous standards available for a mechanical testing laboratory.

Westpak is certified to the requirements of ISO 9001-2008 for quality management, and to ISO 14001-2004 for environmental management and sustainability efforts.

Creep Testing


Creep is the deformation of a material occurring with time due to an externally applied constant stress. For cushioning materials specifically, it may be defined as the change in thickness of a cushion under

static compressive load over a period of time.

It is also referenced as a procedure designed to determine the resistance of a shipping container to a vertically applied constant load for either a specified time or to failure. The test method may also be used for palletized or unitized load configurations.

Another test method covers determining the resistance of an empty paper corrugated shipping container to a vertically applied constant compression load for a specified time. The test method may also include palletized or unitized loads made of such containers. The boxes are tested in the orientation that they are most likely to be stacked in a unitized or palletized load.

Finally, the term "creep testing" may refer to test methods or procedures for determining the ability of packages to withstand internal pressurization. The creep test maintains a specified pressure for a specified time or until the package fails.

Typical Procedures/Protocols
ASTM D2221
ASTM D3575

More Information
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Westpak Capabilities

Westpak continually upgrades and expands its equipment line-up. Therefore this list is a minimum of our capabilities:

(20) Kertner Creep test box fixtures