Sterling 882.00379.00 Replace or re-install worn, Or misaligned gaskets, Hopper discharge flapper

Problem	Possible Cause		Possible Remedy
			∙	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.
	Vacuum leak(s) in vacuum		∙	Internal check valves
				missing or damaged. On
	hoppers.
				single line Y systems,
				internal check valves must
				be installed in the vacuum
				hoppers to seal all hoppers
				not being conveyed to. If
Vacuum conveying rate is				the check valves are
				present and undamaged,
declining due to a vacuum
				they may be pushed too
loss in the system.
				far onto the tube stub to
(Cont’d.)				permit a proper seal. Also,
				if the hopper is over-filled,
				the check valve may not
				seal properly.
	Vacuum leaks in material	Check for leaks as described
	lines.	in previous steps.
			Too much air and not
			enough material or too much
			material and not enough air.
			Close takeoff compartment
			material inlet, slowly open
	Material take-offs not		until you hear material
			surging and slugging. Close
	properly adjusted.
			material inlet until surging
			disappears. On most
			systems, a proper adjustment
			generates a 6” to 10” Hg
			(203 to 339 millibars)
			vacuum.
	The blower is dead-headed.		Check the blower inlet for
			obstruction.

Conveying System Mechanical Components Chapter 6: Troubleshooting 100 of 138