DANGER
Crushing hazard
Death or serious personal injury
‐
Never work under a pump when it is
hanging from a crane.
Before adjusting the clearance, clean the
gap between the impeller and the inlet
cover.
1. Loosen all fastening screws and set screws
between the inlet cover and the pump housing.
2. Use a hammer to tap at the inlet cover and close
the clearance.
3. Open the clearance to the specified value by
turning the three set screws.
4. Check that the clearance is even around the
perimeter of the inlet opening.
5. Tighten the fastening screws and check that the
clearance is still even.
6. Turn the impeller by hand and check at several
points.
TM033621
Impeller clearance, installation types S, C and ST
8.4.2 Dry-installed pumps, installation types D
and H
The impeller clearance can be inspected and set with
the pump installed on the pump stand and connected
to the pipes.
In these pumps, the inlet cover is located between the
pump housing and the outer connection flange at the
inlet side of the pump.
Depending on the construction, there are two ways to
set the impeller clearance.
Method 1
Pump types
Ranges 72 and 74
S2.90.xxx.xxxx.x.xxx.
S2.100.xxx.xxxx.x.xxx.
S3.135.600.xxxx.x.xxx.
Range 78
S3.115.xxx.xxxx.x.xxx.
S3.130.xxx.xxxx.x.xxx.
S3.145.xxx.xxxx.x.xxx.
S4.135.xxx.xxxx.x.xxx.
50
35
12c
12a
L
S = 1.3 ± 0.2
A-A
A-A
TM033073
Impeller clearance, installation types D and H,
method 1
These pump types have threaded holes for the
fastening screws (35) of the inlet cover (12a) in the
pump housing (50). Set the impeller clearance as
follows:
1. Loosen the three set screws (12c) and close the
impeller clearance "S" by tightening the six
fastening screws (35) diagonally to move the inlet
cover evenly.
Do not use undue force when tighten-
ing the fastening screws as this may
damage the bearings. The movement
is usually 1 to 3 mm.
2. Measure the distance "L" between the inlet cover
and the pump housing at three points next to the
set screws, using feeler gauges or calipers, then
note the distance.
35
English (GB)
Summary of Contents for ST-55-520
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