ITT GOULDS PUMPS 3180, Инструкция по установке, эксплуатации и обслуживанию

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Evenly adjust each of the two gland bolts with a one-quarter (1/4) turn until the desired leakage rate is
obtained. Tighten the bolts to decrease the rate. Loosen the bolts to increase the rate.
Tightening of packing
NOTICE:
Never over-tighten packing to the point where less than one drop per second is observed.
Over-tightening can cause excessive wear and power consumption during operation.
If you cannot tighten the packing to obtain less than the specified leakage rate, then replace the packing.
6.3.3 Dynamic seal maintenance (3180 and 3185 S, M, L, and XL groups
only)
Precautions
WARNING:
• Packed stuffing boxes are not allowed in an ATEX-classified environment.
• Dynamic seals are not allowed in an ATEX-classified environment.
Dynamic seal parts
Dynamic seal parts normally do not wear enough to affect operation unless the service is particularly
abrasive. The dynamic seal consists of two parts:
• The repeller seal prevents leakage during operation.
• The secondary seal prevents or minimizes leakage during shutdown of the unit. The seal can be
either one of these types:
• Graphite packing, provides adequate life when it runs dry but can provide longer performance
if it is lubricated with clean water (Flush) or grease via a spring loaded grease cup.
• Diaphragm seal, which is an elastomeric disk that seals against a follower when the pump is
not operating.
Repeller seal maintenance
Some services might require a flush if solids have built up on the repeller. The unit contains a flush tap
for that purpose. The unit also contains a drain tap in order to drain the repeller chamber if there is a
danger that the unit might freeze.
Graphite packing maintenance
Graphite packing requires the same maintenance as any other packing. When adjustments can no lon-
ger be made with the gland because it contacts the box face, perform these maintenance tasks:
• Shut down the pump.
• Relieve the pressure.
• Add another ring of packing to the box.
If the lantern ring connection is used but no longer lines up with the flush port, you need to clean and
repack the stuffing box. The repacking procedure is the same as the procedure outlined in the Commis-
sioning, Startup, Operation, and Shutdown chapter except this is the arrangement:
• One ring of packing
• The lantern ring
6.3 Shaft-seal maintenance
76 Models 3180, 3181, 3185, and 3186 Installation, Operation, and Maintenance Manual