In 2009, a New Jersey-based asphalt company approached Wm. W. Meyer & Sons seeking a solution to an issue they were having with a competitor’s airlock ability to hold a seal. The valve was lined with ceramic tiles and was supposed to have a one-year lifetime in that particular system. Unfortunately, the asphalt company realized the valves were only lasting 5-6 months at the most. The limited lifespan on the rotary valve ended up costing the asphalt company more than double what they had budgeted for their rotary valves and a significant loss of production time.
      Meyer traveled to the asphalt company’s facilities in New Jersey to take a look at the application and determine what type of solution could be found for the air leakage problem. After seeing the process, which was running rock dust at 25 tn/hr, and discharging into a 6-in. conveying line at 8 PSI, it was determined that the air leakage was being caused by wearing on the valve. Wm. W. Meyer & Sons suggested its screw pump as a solution for this application.
      The screw pump has a special coated steel machined shaft that doesn’t wear nearly as quickly as the ceramic tiles that were on the previously installed airlock. Since the shaft on the screw pump wears significantly slower than a rotary valve does, it creates a much tighter seal and provides for a longer life. The tighter seal on the screw pump would also give them the added advantage of improving the conveying efficiency in their system.
The asphalt company felt reassured that the screw pump was the right choice for this application and removed the installed rotary valve and replaced it with the suggested screw pump.
       The screw pump was delivered and installed in time for the 2010 asphalt season. It solved the problem and has run for two years with no lost productivity or unscheduled downtime.
       For more information, visit www.wmwmeyer.com.