KSB GIW MDX, Инструкция по установке и эксплуатации

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MDX [en-US]
47
Bolt Size
Distance per Full Turn of
Adjustment Bolt
Bolt Size
Distance per Full Turn of
Adjustment Bolt
ENGLISH inch mm METRIC inch mm
3/4" – 10 NC 0.100 2.54 M20 – 2.5 0.098 2.50
1" – 8 NC 0.125 3.18 M24 – 3.0 0.118 3.00
1 1/8” – 7 NC 0.143 3.63 M27 – 3.0 0.118 3.00
1 1/4" – 7 NC 0.143 3.63 M30 – 3.5 0.138 3.50
1 3/8” – 6 NC 0.167 4.23 M33 – 3.5 0.138 3.50
1 1/2" – 6 NC 0.167 4.23 M36 – 4.0 0.157 4.00
1 3/4” – 5 NC 0.200 5.08 M42 – 4.5 0.177 4.50
2” – 4 ½ NC 0.222 5.64 M48 – 5.0 0.197 5.00
10.4 Setting the Nose Gap
CAUTION
The final movement of the bearing housing during adjustment should always be away from the impeller end, as
described above. This ensures that the threads of the adjusting screw will contain no backlash against the
forward directed thrust loading that the pump will generate during operation. It is especially important that this
convention be followed when a mechanical seal is being used.
In order to maximize the performance of your pump, the clearance between the suction face of the impeller and the suction liner
must be adjusted to an allowed minimum depending on the size and type of bearing assembly. This is done by moving the
bearing housing assembly with the adjusting screw. Setting the nose gap must be completed prior to initial commissioning of
the pump and following the replacement of any spare parts.

Before adjustment may proceed, the pump wet end must be completely assembled.
o
Stuffing Boxes may be packed before or after the adjustment procedure.
o
Mechanical seal axial set must be left until after the adjustment is complete.
o
Pumps with urethane or rubber lined parts should also have the suction spool or suction piping installed and
torqued prior to nose gap adjustment.

Ensure that all of the bearing housing hold down bolts are slightly loosened.

Run the bearing assembly towards the impeller end by means of the adjusting screw until the impeller first begins to
rub the suction liner. It is helpful to slowly rotate the impeller during this procedure.

Reverse the adjusting screw until the clearance between the impeller and the suction liner is brought to the
recommended values shown in below.

Confirm the shaft can rotate 360° by hand with no resistance to ensure minimum nose gap has been achieved all
around. Always rotate the shaft in the direction of pump rotation. Clearance should be set from the point where free
rotation is achieved with minimal resistance.

Once the clearance is correct, tighten the bearing housing hold down bolts according to the requirements of Section
8.4 “Bearing Assembly Mounting” and recheck clearance.

Firmly lock the adjusting screw and nut together against the bearing housing tab and again confirm that the shaft can
rotate freely 360° by hand.