KSB CHTRa, Инструкция по установке и эксплуатации

Страница: 89 / 116

7 Servicing/Maintenance
89 of 116
CHTRa
Heating the impeller for removal
Impellers must be heated for removal.
1
2
Fig. 38: Impeller sections
1 Impeller’s circumference 2 Impeller’s hub
When heating the impellers on the shaft observe the following:
▪
Apply heat to the balance drum on the shaft using a torch with a fine tip.
▪ Never start heating the impeller at the hub. Additional heating of the hub area
at this time will tighten the impeller on the shaft, not loosen it.
▪
Do not apply heat directly to the shaft as this will cause it to expand.
▪ Heat the impeller on the circumference.
▪ Heat the impeller until the temperature reaches approx. 190 °C to approx. 210 °C.
▪
Heat the impeller until the temperature reaches approx. 374 °F to approx. 410 °F.
▪ After reaching the required temperature remove the impeller by pulling towards
the shaft end.
▪ If the impeller cannot be easily pulled off the shaft, additional heat may be
necessary.
▪
If the impeller still fails to come free, the impeller and shaft should be allowed to
cool completely and repeat the heating process.
1. Remove casing wear ring 502 from impeller 230 by pulling towards the shaft
end.
2. Heat the impeller as described.
3. Slide the heated impeller a short distance towards the middle of the pump.
CAUTION
Improper assembly/dismantling
Damage to thrust ring!
▷
Use a suitable tool to bend open the thrust ring until it can be pulled from the
shaft.
▷ Never bend the thrust ring excessively.
4. Bend open thrust ring 501 and remove from shaft 210 by pulling towards the
shaft end.
5. Remove impeller 230 from shaft 210 by pulling towards the shaft end.
6. Remove key 940 from shaft.
7. Remove casing wear ring 502 from impeller 230 by pulling towards the shaft
end.
8. Remove interstage bush 541 from the shaft. The last stage on both the drive end
and non-drive end does not have an interstage bush.
9. Repeat the dismantling process for all further impellers.