Flowserve MARK 3 GROUP 4 - Manual (Page 34)

MARK 3 GROUP 4 USER INSTRUCTIONS ENGLISH 71569286 08-12
Page 34 of 48 flowserve.com
®
6.6 Fastener torques
Non-metallic gaskets incur creep
relaxation – retighten to the tightening torques
provided.
All torques specified subject to a tolerance of +/- 10%
Bolt size
Torque Nm (lb ft)
Pump feet
fasteners
All other fasteners
M 16 (⅝ in.)
M 20 (¾ in.)
M 24 (⅞ in.)
M 27 (1 in.)
M 30 (1⅛ in.)
M 36 (1⅜ in.)
M 42 (1⅝ in.)
M 48 (1⅞ in.)
170 (125)
340 (250)
590 (435)
770 (570)
1 100 (810)
1 840 (1 350)
2 000 (1 475)
2 240 (1 650)
84 (62)
165 (120)
285 (210)
375 (275)
540 (400)
900 (660)
1 410 (1 040)
2 060 (1 500)
IMPELLER NUT
TIGHTENING TORQUE
FRAME 4K
Nm lbf.ft.
400 300
TIGHTENING TORQUE FOR STAINLESS STEEL
STUDS
WITH LUBRICATED THREADS
THREAD SIZE TIGHTENING TORQUE
Nm ft. lb.
M10x1.5 (3/8–16UNC) 13 10
M12x1.75 (1/2–13UNC) 27 20
M16X2 (5/8-11UNC) 60 45
M20x2.5 (¾-10UNC) 100 75
6.7 Renewal clearances
As wear takes place between the impeller and casing
the overall efficiency of the pump set will decrease.
To maintain optimum efficiency it is recommended
that the impeller be adjusted to maintain the impeller
axial clearance as detailed in section 6.11 to
clearance as detailed in table 3.5. Typically doubling
the clearance can reduce performance by 5%
depending on pump size and operating condition.
6.8 Disassembly
Refer to section 1.6,
Safety
, before dismantling
the pump.
Before dismantling the pump for
overhaul, ensure genuine Flowserve replacement
parts are available.
To disassemble the pump consult the sectional
drawings, see section 8,
Parts list and drawings
.
6.8.1 Rotor unit
The following procedure is recommended for
removing and disassembling the back pull-out
element (rotating assembly).
Note that the replacement gaskets and
similar consumable materials should be available
since they will be required for reassembly.
a) Isolate motor and lock off electrical supply in
accordance with local regulations.
b) Isolate suction and discharge valves.
c) Remove coupling guards and disconnect the
coupling halves.
d) Drain pump casing. Remove any auxiliary piping
if applicable.
e) Disconnect stuffing box, cooling water and
auxiliary piping.
f) Drain the oil from the bearing frame [3130] if
bearing frame is being dismantled.
g) Place the sling around the bearing frame [3130]
and carefully take up the weight without straining
the casing. Refer to Section 3 to determine hoist
and sling requirements.
h) Release the thrust bearing housing [3240] hold
down bolts and jam nuts. While rotating the
pump shaft [6] by hand, tighten the three jacking
screws evenly until the impeller [2200] lightly
clamps the stuffing box head [4110] in place.
This will simplify withdrawal of the rotating
element from the casing.
Excessive clamping force could
damage bearing races.
Rotating the shaft helps to clear away solids
which may be trapped between the impeller and
stuffing box head.
i) Remove the bolts connecting the rear support
foot [3134] to the baseplate.
j) Remove the frame to casing bolts
k) Withdraw the rotating element from the casing.
6.8.2 Stuffing box
6.8.2.1 Shaft seal - mechanical seal
Refer to any special instructions supplied with the
mechanical seal.
a) Remove seal cover screws and pull off seal cover
complete with the stationary seal ring which is
held in place by the O-ring seal.