Inserting The Plunger; Installing The Gland; Installing The Stuffing Box; Connecting The Plunger - Pentair Myers Aplex Series Installation And Service Manual

correctly. This is most easily done before installing
the plunger.
Lantern rings are provided with O.D. and I.D. reliefs
and two (or more) oil holes to allow lubricant to reach
the plunger. After the last unit of Styles 838 and 858
packing is in place, generously oil the lips of all seal
rings to ease plunger entry.

INSERTING THE PLUNGER

Apply oil liberally to plunger O.D. and lightly tap it
through the packing.
A soft rubber mallet is recommended to avoid any
damage to the plunger face or its threads. Remember:
The fragile nature of packing rings and plunger
surfaces deserves your respect and avoidance of
careless damage to these key elements!

INSTALLING THE GLAND

Considerable downward pressure on the gland is
required to compress the spring, to move the packing
into location, and to start the threads of the box.
Once the gland threads are started, screw it down
completely until it makes up tightly against the face of
the box, for spring loaded packing. For Hi/Lo, J-Style
or Gland adjusted packing, tighten the gland until it is
seated firmly against the packing.

INSTALLING THE STUFFING BOX

Myers Aplex Series stuffing boxes derive their alignment
from the bores of the power frame and the faces of the
fluid end. So these surfaces must be cleaned of rust, scale,
and dirt before assembly is begun. Wash all contacting
surfaces with clean solvent and dry with a clean shop
towel.
A nitrile rubber seal is used to seal between the face of the
fluid end (must be flat, clean and smooth) and the
face of the box. Replace if damaged.
All stuffing boxes are retained by four large studs and nuts
which extend through the power end, serving to clamp the
box and the powerframe tightly against the fluid end face.
These four stud nuts must be evenly tightened.
Using a socket, socket extension, and torque wrench,
tighten clean, well-oiled threads and nut faces.
Stud Threads
1" – 8UN at 1" – 8UN at
440–465 Ft. Lb. 400–465 Ft. Lb.
SC-170
SC-170H
MA-95M MA-120L-HD
MA-120M
SC-170L
MA-120L
FLUID END
Disassembly/Assembly:
When removing fluid end, pump several gallons of clean
water through before service is performed to remove
contamination left behind. Inspect fluid end for stress
cracks to determine if replacement is necessary. Inspect
and clean all openings for contamination.
Disconnect suction/discharge piping before disassembling
the fluid end. Remove the stuffing boxes and nuts between
the fluid and power end. Support the fluid end while sliding
the assembly away from the power frame.
Reverse procedure to reassemble and torque all fluid end
nuts to 750 Ft. Lbs.

CONNECTING THE PLUNGER

Install the metal baffle plate on the extension rod and roll
the pump slowly until the extension rod male threads just
touch the mating plunger female threads.
Applying a pipe wrench to plunger knurled area, thoroughly
tighten the connection. Do not use a "cheater" when
connecting plunger to extension rod. (Serves no useful
purpose, and may damage the connection!)

PACKING

Packing life for aramid fiber packing may be improved
in some applications by regular, systematic lubrication.
An optional force feed lubricator assembly is often
recommended especially for pumps on continuous duty.
This provides regular, controlled supply of lubricant
lowering friction and heat.
Additionally, the regular application of the correct lubricant
aids dissolving of salt and gyp tending to build up on the
plungers in produced water applications. For this service,
Rock Drill Lubricant is a popular and effective packing
lubricant.
Plungers in CO , ethane, or other very cold liquid services
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may use brake fluid. This fluid does not congeal into a
solid which cannot enter the packing. Consider the use of
an air-sealed cradle into which dry (instrument) air may
be directed, excluding the moisture which causes plunger
icing especially in very humid conditions.
Packing lubricant for pumps on light hydrocarbons,
hot water, lean oil, naphtha, or gasoline often requires
experimentation.
A good start is to use steam cylinder oil. Castor oil is
sometimes successful as a packing lubrication for liquid
propane and butane services, at ambient temperature.
In pumps placed in arctic service, a special low pour point
oil is indicated.
Packing lubrication is not permitted on some services,
such as amine, food stuffs, etc., and other packing styles
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