Flowserve Worthington WXB - Manual (Page 32)

WXB USER INSTRUCTIONS ENGLISH - 07/14
Page 32 of 51
6.7.4 Dismantling of mechanical seal
1) Secure the mechanical seal by putting the
mounting plates into the groove of the shaft
sleeve. Loose the grub screws, and disconnect
the seal piping.
Drain the seal system, if
applicable.
2) Loose hex nuts [6581.4] and pull off mechanical
seal cartridge from the shaft. [2100]
6.7.5 Dismantling of hydraulic cartridge
1) Start at the line bearing side first following chapter
6.7.2 and 6.7.4.
2) As next step dismantle the thrust bearing side
following chapter 6.7.3 and 6.7.4.
3) The further dismantling has to be executed from
the thrust bearing side. Remove the o-ring [4610.4]
and draw the stuffing box housing [4110] out of
the discharge casing [1140].
4) Open the hex nuts [6581.1] of the studs [6572.1]
and dismantle the pump stage by stage beginning
at thrust bearing side.
5) First off all loose the socket head cup screws
[6579.2] at the balancing drum [6230]. Then
remove the clamping ring [1240], which is fixing
the retaining ring [2530]. Now pull the balance
drum [6230] from the shaft.
6) Now take the cup spring [4263] and the diffuser
last stage [1410.2]out of the pump.
7) Start to dismantle the pump stage by stage. All
parts of a stage (impeller [2200.1, 2200.2],
diffusers [1410.2, 1410.1] and stage casing
[1160.1] have to be numbered to assure a
reassemble in original sequence. The availability
of a crane to secure the heavy parts would be very
helpful, to avoid that they will fall on the shaft and
damage or bend it.
8) Support the stage casing which is next to the
discharge casing. Lift the discharge casing
inclusive the bush [1600], which is fixed on it and
also the diffuser of the last stage [1410.2] which is
close in the casing. When necessary remove the
bush from the discharge casing by loosen the
socket head cap screws [6579.3]. By removing the
o-ring [4610.6] out of the discharge casing with the
help of a sharp tool also the diffuser can be
removed.
9) Now draw off the impeller [2200.1] with the
impeller wear ring [2300.1] from the shaft. Then
take the key [6700.1] out of the groove and
support the next stage casing [1160.1] which is
closer to the suction casing and lift the last stage
casing inclusive diffuser [1410.1] and casing wear
ring from the pump.
10) As next step remove the interstage sleeve [2410]
and the impeller [2200.1] with the impeller wear
ring[2300.1] from the shaft. Now take again one
key [6700.1] from the shaft and support the next
stage casing. Remove the next stage casing still
you have reached the suction casing [1130].
11) Remove the impeller first stage [2200.2] with the
impeller wear ring [2300.2]. Then you can draw the
shaft out off the suction casing. Pull out the suction
casing [1130] from the casing [1100]. In the
suction casing you can find the casing wear ring
for the first stage [1500.2].
Pumps equipped with an inducer
have a separate stage casing in front of 1st
stage impeller.
6.8 Examination of parts
1) Check the casing wear ring and the impeller wear
ring against any wear. The diametrical clearance
between the rings must not exceed twice the
value in new condition.
2) Check all parts against corrosion and erosion.
3) Carefully check the coupling against any wear.
Rotate the angular contact bearing by hand, to
check against abnormal sound. Check the
bearing cages against any wear and the outer
and inner race against running marks. Check the
runout of the shafts. TIR (Total Indicated Runout)
shall not exceed 0.04 mm/m (0.0005 in./ft) of
length. TIR shall not exceed 0.08 mm (0.003 in.)
over total shaft length.
6.8.1 Gap between particular parts
The diametrical gap between casing wear rings
[1500.1, 1500.2] and impeller wear rings [2300.1,
2300.2] in assembled condition is:
Pump
size
Material
Diametrical
gap
diametrical gap between
balance drum [6230] and
bush [1600] mm (in.)
2 WXB
Steel rings
mm (in.)
0,4 (0.016)
0,3
(0.012) Stainless
rings
mm (in.)
0,5 (0.019)
3 WXB
Steel rings
mm (in.)
0,45 (0.017)
0,4
(0.016) Stainless
rings
mm (in.)
0,55 (0.022)
4 WXB
Steel rings
mm (in.)
0,45 (0.017)
0,35
(0.014) Stainless
rings
mm (in.)
0,55 (0.022)
6 WXB
Steel rings
mm (in.)
0,45 (0.017)
0,4
(0.016) Stainless
rings
mm (in.)
0,55 (0.022)
The diametrical gap between diffuser [1410.1] or
interstage bush [1610] and interstage sleeve [2410] is
0,25 mm (0.010 in.).