New features of 660 MW Units Turbine Maintenance Sipat Super thermal - PowerPoint PPT Presentation

New features of 660 MW Units Turbine Maintenance Sipat Super thermal power project

New features of 660 MW units • Constructional features • Operational features • Lube oil system • Governing system • Feed water system • Turbine Auxiliaries

Specifications • Make OJSC Power machines, Russia • Design LMZ, Russia • Type K-660-247 Four Cylinder, tandem compound, Reheat, Condensing Turbine Spring deck foundation • Stages HPT, reverse flow, 17 (1-control stage,16 Reaction stages) IPT 11 X 2 impulse stages. LPT 2 nos. - 5 X 2 impulse stages. • No of HP Control Valve 4 • No of IP Intercept valves 2 • No of IP Governing valves 4 • Over all length of turbine 35.8 Mtr • Direction of Rotation Clockwise (Viewed from front pedestal towards Generator)

Main features • Turbine: HPT, IPT, LPT1 and LPT2 • Two condensers for Main Turbine • TG Bearings: 12 • Turbine Stop Valves: 04 (HPSV-1&2, IPSV-1&2) • Turbine Control Valves: 08 (4 HPCV & 4 IPCV) • CRH Check Valves: 02 ( With Bypass lines for warm up) • IP Turbine has throttle governing – all four control valves open simultaneously • HP Turbine has nozzle governing – all four control valves open in preset sequence • LP heaters – 1a, 1b, 2, 3 & 4 • HP heaters – 6A, 6B, 7A, 7B, 8A & 8B • Steam coolers – one each for HPH 6A & 6B • 2 MDBFP (2 X 30%) • 2 TDBFP (2 X 50%) • Separate condensers and vacuum pumps for TDBFPs

HP Turbine IP Turbine LP Turbine # 1 LP Turbine # 2 540ºC 247 KSc 298ºC 47.9 KSc 565ºC 43.1 KSc MS CRH HRH Governing Box 349ºC 68.8 KSc LPH#1 LPH#1a LPH#1 LPH#1b CRH HPH#8A HPH#8A Deareator Deareator LPH#4 LPH#4 HPH#7A HPH#7A HPH#8B HPH#8B HPH#7B HPH#7B LPH#3 LPH#3 Steam cooler Steam cooler LPH#2 LPH#2 HPH#6A HPH#6A HPH#6B HPH#6B

Main parameters Parameters Units Value Live steam consumption, HPT inlet t/h 2023.7 MPa (kgf/cm 2 abs) Rated total pressure of live steam, HPT inlet 24.2 (247) ° С Live steam rated temperature 537 ° С T after HPT exhaust 297.8 4.8 (47.9 MPa (kgf/cm 2 abs) P after HPT exhaust kgf/cm 2 ) 4.3 (43.1 MPa (kgf/cm 2 abs) Steam absolute pressure before IP SV kgf/cm 2 ) Live steam consumption , IPT inlet 1678.5 t/h ° С steam temperature before IPSV 565 MPa (kgf/cm 2 abs) steam absolute pressure in condenser 0.105 ° С Inlet condenser CW temp 33 cooling-water consumption m 3 /h 64000

Extraction Steam parameters Pressure (bar) – Temperatures ( o C) Locations Absolute Initial steam HPT inlet 247 537 HP cylinder exhaust 48 298.50 IP cylinder stop valve Inlet 43.20 565 Extraction 8 (HPT 13 th stage to HPH 8) 68.8 349 Extraction 7 (CRH to HPH 7) 45.6 295.62 Extraction 6 (IPT 3 rd stage to HPH 6 & 21.7 470 TDBFP) Extraction 5 (IPT 6 rd stage to Deareator) 11.34 374.28 Extraction 4 (IPT 8 th stage to LPH 4) 6.25 301 Extraction 3 (IPT 11 th stage to LPH 3) 2.97 214 Extraction 2 (LPT 2 nd stage to LPH 2) 0.624 0.79% / 89 Extraction 1 (LPT 4 th stage to LPH 1) 0.264 4.38% / 68 LP cylinder exhaust 0.105 7.84%

Operational features • Turbine rolling by IPT • HPC & IPC flange heating system • IP Turbine rotor cooling system • Turbine motorized barring gear • Jacking oil for bearing shell & rotor • No Main oil pump • Separate governing box in front pedestal • High pressure governing system • Pressurized damper tanks with no separate air / h2 seal oil pumps • HP / LP Bypass control system similar to 500 MW unit HP Bypass system

HP Turbine • Reverse flow turbine (1 – 9 stages: left flow, 10 -17 stages: right flow) • 17 stages (1 control stage + 16 reaction stages. • Type of Casing: Horizontally split inner & outer casing • Four main steam inlet and two cold reheat outlet • No balance drum / balance piston arrangement • Extraction steam from HP Casing in 13 th stage to HP Heater # 8. • Stationary blades are fixed in casing. No diaphragms in HPT • Flange heating system from HRH source.

HP Turbine

HP Turbine Material: – HP outer casing: 15Cr1Mo1V – HP blade carrier/casings: 15Cr1Mo1V – HP shaft: 25Cr1Mo1V – HP Turbine Moving Blades first stage (1-5): 18Cr11MoNiVNb – HP Turbine Moving Blades stages (6-17): 15Cr11MoV – HP Turbine Fixed Blades first stage (1-5): 18Cr11MoNiVNb – HP Turbine Fixed Blades stages (6-17): 15Cr11MoV – HPT Casing Joint Bolts: 20Cr1Mo1V1TiB, 25Cr1MoV, 18Cr12WMoNbVB – Shaft Couplings: 25Cr1MoV – HP Labyrinth Seals: 20CrMo, 15CrMo

IP Turbine • Double flow turbine (2 X 11 impulse type) • Type of Casing: Horizontally split inner & outer casing • All four HRH steam inlet from bottom side • IP Turbine stationary blades (1 st & 2 nd stages) cooling system from CRH & HRH source. • Flange heating system from HRH source. • Stationary blades are fixed in diaphragms • Balance holes: 10 holes / ST (2nd stage to 11th stage)

IP Turbine

IP Turbine

IP Turbine Material: – IP outer casing: 15Cr1Mo1V – IP Inner casing: G-X 12CrMoVNbN9-1 – IP shaft: 26CrNi3Mo2V – IP Turbine Moving Blades first stage (1-3): 18Cr11MoNiVNb – IP Turbine Moving Blades stages (4-11): 15Cr11MoV – IP Turbine Fixed Blades first stage (Ist ST): 18Cr11MoNiVNb – IP Turbine Fixed Blades stages (2-11): 15Cr11MoV – IPT Casing Joint Bolts: 20Cr1Mo1V1TiB, 25Cr1MoV, – 18Cr12WMoNbVB – Shaft Couplings: 25Cr1MoV – IP Labyrinth Seals: 20MnSi

LP Turbine # 1 & 2 No of LP Turbine: 2 Type of turbine cylinders: Double flow Type of Casing: Horizontally split inner & outer casing No of Stages: 2 X 5 (impulse) Last Stage Blade height: 1000 mm Extraction Steam at 2 nd stage & 4 th Stage Last stage – locking shrouded blades with lacing wire

LP Turbine 1 & 2

LP Turbine

LP Turbine Material: – LP inner & outer casing: Steel 3 – LP shaft: 26CrNi3Mo2V – LP Turbine Moving Blades first stage (1-2, 3-4): 20Cr13, – 15Cr11MoV – LP Turbine last stage moving blades: 13Cr11Ni2W2MoV – LP Turbine Fixed Blades first stage (1-4): 12Cr13 – LP Turbine Fixed Blades stages (5): 08 Cr13 – LPT Casing Joint Bolts: Steel 25 – Shaft Couplings: 25Cr1MoV – LP Labyrinth Seals: 26CrNi

Flange heating system From HRH From HRH To condenser 1. Put into operation by operator during cold and warm start-ups of the turbine 2. To decrease differential temperature of HPC and IPC flanges, and to prevent inadmissible relative extensions of HPC and IPC rotors 3. Without flange heating system turbine can be started up but the start up time shall be increased by 30-60 minutes

HPC Flange heating • HPC flange heating is put into operation when relative expansion of rotor > +3.0 mm or differential temperature across the width of any HPC flanges > 40 ºC. • Conditions for putting in operation: – Steam pressure in hot reheat pipeline is above 6.0 kg/cm2 – Steam temperature in hot reheat pipeline is above 150 ºC – Pressure in main turbine condensers is below 0.5 kg/cm2 (abs). • Supply header temperature > 150 ºC and 35 ºC above outer surface temperature of any flange. • In auto mode initial 15 min the pressure is maintained at 0.5 Ksc • After 15 mins, pressure is increased to 5 Ksc and drain valve is closed.

HPC Flange heating • HPC flange heating is put out from operation when – Relative expansion of rotor < - 1.0 mm or – Temperature difference between outer surface temperature of any HPC and HPC top or bottom > 80 ºC or – if the HPC top metal temperature exceeds 350 ºC • HPC flange heating is put out from operation by – The gate valve closes on the HPC flange heating steam supply line. – Control valve closes and drain opens

IPC Flange heating • IPC flange heating is put into operation when relative expansion of rotor > +1.0 mm or differential temperature across the width of any HPC flanges > 40 ºC. • Conditions for putting in operation: – Steam pressure in hot reheat pipeline is above 6.0 kg/cm2 – Steam temperature in hot reheat pipeline is above 150 ºC – Pressure in main turbine condensers is below 0.5 kg/cm2 (abs). • Supply header temperature > 150 ºC and 35 ºC above outer surface temperature of any flange. • In auto mode initial 15 min the pressure is maintained at 0.5 Ksc • After 15 mins, pressure is increased to 5 Ksc and drain valve is closed.

IPC Flange heating • IPC flange heating is put out from operation when – Relative expansion of rotor < - 1.0 mm or – Temperature difference between outer surface temperature of any IPC and IPC top or bottom > 80 ºC or – if the IPC top metal temperature exceeds 350 ºC • IPC flange heating is put out from operation by – The gate valve closes on the IPC flange heating steam supply line. – Control valve closes and drain opens

IP Rotor cooling system • IP Turbine rotor cooling system is provided from HRH and CRH source.

HRH Strainer Screw Jacks

660 MW Turbine casings Bearing No 2 Bearing No 3