CapstanAG PinPoint III ENVELOP, Operator'S Manual

Page: 82 / 128

TM
Maintenance
Plunger Seal Inspection
Figure 30:
After extended use, the plunger seal will wear a groove (1) where the seal impacts the hard orifice
seat. Replace the plunger if worn or damaged.
As the groove deepens, the pressure capacity of the valve will decrease until the pressure capacity
interferes with the operating pressure of the system.
The result is erratic pulsing, often described as “flickering.” The system will operate normally at lower
pressures until replacement parts can be installed. High operating pressures and abrasive chemicals
will accelerate the wear of the plunger seal material.
Figure 31:
When replacement of the plunger is necessary, make sure that you have the correct plunger:
(1) Standard Flow—4 slots on the outside
(2) Standard Flow—2 slots on the outside
(3) Heavy Spring—The spring (4) on the plunger has a larger diameter than the spring on the
standard valve plunger.
©
2021 Capstan Ag Systems, Inc.
82
PinPoint
™
III ENVELOP