A processor making chemicals for use in the aerospace industry was having problems sealing a horizontal rotary vacuum dryer. One particular requirement they had was that the seals could not allow grease or particles from packings to enter the process. They had been using an unsplit, double-faced mechanical seal, which was not able to hold vacuum, causing drying times to be excessively long. The seals were expensive to replace and failed frequently.
The dryer’s shaft diameter is 10.5” (267 mm), turning at 4 rpm. Process temperature is 160°C/320°F and pressure ranges from 20mm Hg vacuum to 14 psig. Different products are dried in the dryer in separate batches. The products consist of abrasive pastes, containing a variety of solvents. No single elastomer material was compatible with all of the processes, so MECO designed a mechanically-driven ( elastomer-free ) “Ex-Pac” model seal for the dryer.
The MECO seals hold the vacuum throughout the cycle, causing the drying process time to be shortened by 50% on many batches. Other advantages provided by the MECO seals include accommodating both thermal growth and run-out motion of the shaft, as well as changes in process pressure during the drying cycle. No product contamination was observed. The seals’ split design affords quick and inexpensive rebuilds, done annually in this case. Nitrogen consumption for the seal’s purge line is less than 0.25 cfm.
All MECO seals are custom-engineered to suit specific processes. MECO engineers take all factors such as shaft size, speed, runout and process chemistry, temperature and pressure into account when designing each seal.
Since the installation of these seals in 2002, MECO has successfully applied the Ex-Pac seal to dryers at higher temperatures and pressure ranges than those detailed here.
Please also visit us at: Booth #2414 at the International Powder and Bulk Solids Expo in Chicago, May 9-11, 2006, see:
Seals Improve Vacuum Dryer Efficiency
Seals Improve Vacuum Dryer Efficiency
A processor making chemicals for use in the aerospace industry was having problems sealing a horizontal rotary vacuum dryer. One particular requirement they had was that the seals could not allow grease or particles from packings to enter the process. They had been using an unsplit, double-faced mechanical seal, which was not able to hold vacuum, causing drying times to be excessively long. The seals were expensive to replace and failed frequently.
The dryer’s shaft diameter is 10.5” (267 mm), turning at 4 rpm. Process temperature is 160°C/320°F and pressure ranges from 20mm Hg vacuum to 14 psig. Different products are dried in the dryer in separate batches. The products consist of abrasive pastes, containing a variety of solvents. No single elastomer material was compatible with all of the processes, so MECO designed a mechanically-driven ( elastomer-free ) “Ex-Pac” model seal for the dryer.
The MECO seals hold the vacuum throughout the cycle, causing the drying process time to be shortened by 50% on many batches. Other advantages provided by the MECO seals include accommodating both thermal growth and run-out motion of the shaft, as well as changes in process pressure during the drying cycle. No product contamination was observed. The seals’ split design affords quick and inexpensive rebuilds, done annually in this case. Nitrogen consumption for the seal’s purge line is less than 0.25 cfm.
All MECO seals are custom-engineered to suit specific processes. MECO engineers take all factors such as shaft size, speed, runout and process chemistry, temperature and pressure into account when designing each seal.
Since the installation of these seals in 2002, MECO has successfully applied the Ex-Pac seal to dryers at higher temperatures and pressure ranges than those detailed here.
Please also visit us at: Booth #2414 at the International Powder and Bulk Solids Expo in Chicago, May 9-11, 2006, see:
https://forum.bulk-online.com/showth...p?postid=19362
For more information on MECO Shaft Seals, please visit:
https://edir.bulk-online.com/profile...ex-bearing.htm
Attachments
mecoshaft_case_2006 (JPG)
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