Turbine Stress Control is one of the complex logics of BHEL turbine. This presentation clearly explains the Logic, working, calculations and influence of the same on operation of steam turbine. For further details and understanding, I can be reached on tahoorkhn03@gmail.com.

1. PRESENTED BY:
TAHOOR ALAM KHAN
Assistant Manager-Operations,
RPL-Amravati

3.  During startup and shutdown, the internals of turbine are
subjected to temperature fluctuations.
 To achieve safe operation during the total life of turbine and
to prevent premature failure of turbine or parts of it, the
THERMAL STRESS need to be kept under limit.

4. Inner Surface
(In contact with steam)
Outer Surface
(Exposed to Atm)
Tm- Casing metal temp at 50% depth.
Tm
Ti- Casing metal temp at 100% depth.
Ti<

6. TURBINE COMPONENTS WHICH ARE
MONITORED BY TSC
TSC
MSV
MCV
HPSHPC
IPS

7. TSC MARGIN PAGE ON DCS

8. Tsc margin
calculation

9. UPPER MARGIN GRAPH IN DCS

10. LOWER MARGIN GRAPH IN DCS

11. CALCULATION OF MARGINS IN DCS

12. HOW TSC margins
influence
TURBINE CONTROL SYSTEM

13. EHTC BLOCK DIAGRAM IN DCS

14. EHTC BLOCK DIAGRAM ON DCS

15. EFFECT OF TSC
ON
RATE OF RISE
OF
TURBINE SPEED AND LOAD

16. TREND WITH 100% UPPER MARGIN

17. TSC PAGE WITH 30K UPPER MARGIN

18. TREND WITH 50% UPPER MARGIN

19. TSC PAGE WITH 15K UPPER MARGIN

20. HOW OPERATING MODES
S, N & F
MAKE A DIFFERENCE

21. SLOW MODE- S

22. NORMAL MODE- N

23. FAST MODE- F

25.  It compares thermal stresses in monitored components with
the limits for operating modes.
 The reference variable for load increase/reduction are
supplied to the set point control of turbine controller. Thus TSC
acts directly on turbine control

26.  It is associated with 3 operating mode i.e.
SLOW (S), NORMAL (N), FAST (F).
 The smallest temperature margin in the TSC serves as the
set point for the load controller

27.  Online fatigue rate calculations.
 Long term storage of parameters, necessary for fatigue
analysis.

28. THANK YOU