Guidelines for Conducting Cable Blowing Tests

Abstract:
Guidelines for conducting cable blowing tests are described in this paper. It is argued qualitatively that test trajectories with only subsequent bends without straight sections in between them can be useful to accommodate thermal expansion differences of bundles of microducts in the ducts, but that unwanted speed resonances might occur during cable blowing. It is stated that the cable shall always reach the end of the duct in blowing tests with a not too high pressure (e.g. 10 bar), if not cutting back of duct loops is needed. It is recommended to use the same and low end speed, e.g. 20 m/min, for each test. This shall be anticipated by adjusting the air pressure well before reaching the end, to create a stationary situation.