Examination Of Internal Components - Wilo Atmos TERA-SCH Serie Einbau- Und Betriebsanleitung

en
9.6 Examination of internal compon-
ents
9.6.1 Check of wear rings
9.6.2 Check of sleeves
9.6.3 Check of impeller
9.6.4 Check of shaft & keys
9.6.5 Check of bearings
38
Maintenance/repair
Check both wear rings (25) for uneven wear.
ƒ
Measure the bore of the wear ring (25) at intervals around the circumference with an
inside micrometre.
ƒ
Measure the impeller neck diameter at intervals around the circumference with an
outside micrometre. The comparison of both measurements indicates the amount of
diametrical clearance between wear ring and the impeller neck.
Indications for wear ring replacement and restoration of the original clearance:
ƒ
The clearance is 150 % or more of the original design clearance
ƒ
Further deterioration of the hydraulic performance cannot be tolerated in the next
operating period
If one of the indicators is true, replace the wear rings. The clearance between impeller
neck and wear ring must be restored to the original design value. This is done by in-
stalling wear rings with a small bore, bored out to suit the diameter of the impeller.
Examine the sleeves to see if they are grooved or worn. If there are grooves or wear, re-
place the part.
Examine the impeller
ƒ
For damage
ƒ
For corrosive /erosion pitting
ƒ
For Cavitations pitting
ƒ
for Bent or cracked vanes
ƒ
For inlet and outlet vane end wear
If damage is extensive, impeller replacement recommended. Before any decision on re-
pair work, ask Wilo for further information.
Check wear around the impeller neck as described in chapter "Check of wear rings".
Examine the shaft
ƒ
For the trueness
ƒ
for mechanical damage and corrosion
If the shaft is not true within 0.1 mm TIR (Total Indicated Reading), replacement or re-
pair is recommended. Before any decision on repair work, ask Wilo for further informa-
tion.
Examine the shaft keys and keyways for damage and wear. Remove and replace dam-
aged or worn out keys.
The ball bearings fitted on the Atmos TERA-SCH series are greased for life. No main-
tenance is required. Check that bearing rotates freely and smoothly, verify that the
outer ring presents no abrasions or discolouration. If there is any doubt regarding the
serviceability of the bearing, replacement is recommended.
Designation
SCH 150-230
SCH 150-555
SCH 200-320
SCH 200-500
SCH 250-360
SCH 250-380
SCH 250-470
SCH 300-430
SCH 350-500
SCH 400-580
SCH 400-490
Size
6306 ZZ C3
6312 ZZ C3
6308 ZZ C3
6312 ZZ C3
6308 ZZ C3
6312 ZZ C3
6312 ZZ C3
6312 ZZ C3
6312 ZZ C3
6316 ZZ C3
6313 ZZ C3
WILO SE 2020-10