Asphalt producer waits two years for pneumatic pump to fail -- it's still waiting
For many years, Western Paving, Inc., an asphalt production company located in Denver, Colo., had a serious problem. The granite dust collected by its dust collector was so abrasive that every 25 to 35 working days it destroyed the rotary airlock that moved the dust from the collector to a pneumatic air line and back into production.
Needless to say, repair and replacement costs were high, and downtime was frequent and lengthy. As an experiment in September 1986, Western Paving's management replaced the airlock with a pneumatic dry-material pump. If the pump withstood the abrasive dust for at least 4 months, they reasoned, the experiment would be a success. Two years later the pump is still on the job, working 6 days a week, 12 to 16 hours a day.