The presence of air in a pipeline and its impact on operations is probably one of the most misunderstood phenomena in our industry today. Many operational problems are blamed on inadequate thrust blocking, improper pipeline bedding, etc. These problems include broken pumps, valves and pipe, as well as faulty instrumentation readings. In reality, many of these problems are not caused by improper installation of the equipment but by failure to de-aerate the pipeline. It has been said that if a pipeline is properly de-aerated, you can't guarantee against a line break. However, if you don't properly de-aerate a pipeline, you should be prepared for one.