Sterling 882.00379.00 ユーザーズマニュアル

Conveying System Mechanical Components    Chapter 6: Troubleshooting 

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Vacuum leak(s) in vacuum 
hoppers.  

•

  Replace or re-install worn 

or misaligned gaskets. 

•

  Hopper discharge flapper 

not sealing under vacuum. 

1)  Replace worn or 

missing gasket. 

2)  Clean fouled flapper. 

3)  Check counterweight 

for proper operation. 
Repair or adjust as 
needed. 

•

  Internal check valves 

missing or damaged. On 
single line Y systems, 
internal check valves must 
be installed in the vacuum 
hoppers to seal all hoppers 
not being conveyed to. If 
the check valves are 
present and undamaged, 
they may be pushed too 
far onto the tube stub to 
permit a proper seal. Also, 
if the hopper is over-filled, 
the check valve may not 
seal properly. 

Vacuum leaks in material 
lines.  

Check for leaks as described 
in previous steps. 

Material take-offs not 
properly adjusted.  

Too much air and not 
enough material or too much 
material and not enough air. 
Close takeoff compartment 
material inlet, slowly open 
until you hear material 
surging and slugging. Close 
material inlet until surging 
disappears. On most 
systems, a proper adjustment 
generates a 6” to 10” Hg 
(203 to 339 millibars) 
vacuum. 

Vacuum conveying rate is 
declining due to a vacuum 
loss in the system. 
 
(Cont’d.) 

The blower is dead-headed. 

Check the blower inlet for 
obstruction.