Cable Particulation Study For Cleanroom Environments

By W. L.Gore & Associates

Introduction

Particle generation from cables in cable chains is a complex problem for cleanroom environments. To minimize particulation means eliminating as much friction among cables and tubes as possible. Although particulation can be reduced by minimizing moving components, it is impossible to eliminate cable movement in automated manufacturing lines. In addition, the dividers and shelves used to separate round cables and tubes are another source of particulation. If dividers are not used or they are installed improperly, friction among cables and tubes results in creeping, walking, or twisting of these components, which in turn increases particulation.

As much as possible, system designers should reduce the number of moving components and the friction among these components to achieve a low particulation cable system that will last for tens of millions of cycles.

Cable chain manufacturers provide detailed guidelines for proper cable management, which determines the cleanliness of your system. However, cables and cable chains that will be used in cleanroom environments should be tested to identify the particulation characteristics of the cable materials and the interactions of these cables within the overall system.

W. L. Gore & Associates recently contracted with the Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart, Germany, to measure the particulation of two GORE™ cables for ISO cleanroom certifi cation. While the Fraunhofer certification should only be used to compare cables and cable chains evaluated under the same testing conditions, Fraunhofer's tests show that the GORE™ cables maintain the lowest particulation levels for repeated flexing.