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Material Conveying Systems

Modified on Saturday, 31 January 2015 11:51 PM by mpieler Categorized as Consultants Corner
Material conveying systems
Vol. 27 #1, March 2000

Poorly installed tubing joints can be a source of fines generation. Conveying tubing joints must be installed correctly. Care should be taken to ensure the tubing ends have a good perpendicular cut. The tubing ends need to be deburred to eliminate sharp edges. The mating ends of the tubing should be butted against each other within the coupling taking care to avoid creation of a gap.

Conveying velocity is critical in vacuum conveying systems. When the conveying velocity that is too high it will cause the pellets to smear and plate out on the inside of the conveying tubing. This material will buildup and periodically peel off, resulting in what is commonly referred to as angel hair & snake skins which will cause material feed problems. A conveying velocity that is too low will cause line surging & slugging which may result in plugged conveying lines. Adjusting the air to material ratio within the conveying system controls conveying velocity. This adjustment is usually made at the material pick up point with equipment provided by the systems manufacturer.

- Pete Stoughton, Conair

See also:
  • Angel hair
  • Flow surging

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