SUMMER TRAINING REPORT AT

GAIL COPMRESSOR STATION,DIBIYAPUR

SUBMITTED BY: RAHUL KUMAR BRANCH: MECHANICAL

COLLAGE:-NOIDA INSTITUTE OF ENGG AND TECH

TOPIC: - 501-KC5 DEC ENGINE

INTRODUCTION OF PLANT

• GAIL- Gas Authority of India Limited• GAIL is one of the MAHARATNA enterprises and ranks among PSU

public sector unit in India.• It was establish in 16th of August ,1984.• GAIL is India’s flagship natural gas company, integrating all aspects

of natural gas value chain (including Exploration & Production, Processing, transmission, distribution and Marketing) and its related services.

• GAIL covers its main portion in (HVJ) Hazira-Vijaypur-Jagdishpur line .In between this three station there are 6 fertilizers companies and 6 power plant.

• It is one of the largest cross –country natural gas pipeline projects in the world.

• This 1800Km long pipeline was built at the cost of 17 billion rupees(US$280 million)

DIBIYAPUR REGION• Dibiyapur Compressor station is in Auraiya district spread in 1089Kms

of pipeline (from 2” TO 30”) of 18MMSCMD supply.• It is a two stage booster station which boost the incoming gas from

Vijaipur up to 90Kg/cm2 for its consumers.• Compressor station consist 2nos gas turbine generators(GTG), 3nos gas

turbine compressors(GTC) , 2nos of European gas turbine(EGT)• Four Power transformers for the eminent operation of the power

system.• For Uninterrupted Power Supply (UPS), there is a battery room

containing Ni-Cd Batteries.• Major customers- PATA, NTPC, IGFCL, IFFCO, BHEL, KSFL, CUGL, GGL

AND TCL.• Sale of NG(natural gas) in DIBIYAPUR region is approx 18 MMSCMD.

PIPELINE INTRODUCTION• At Pressure of 58Kg/cm2, received from GAIL Vijaipur, through 30” HVJ

Pipeline.• This total rich natural gas (Feed gas ) is passed to GAIL Pata, where rich

gas is converted into lean gas, which has 98.5% of C1, is received back at the compressor station from GAIL, Pata, at pressure of 48Kg/cm2.

• Approx. 3.2 MMSCMD of this lean gas is supplied through pressure reduction skid to NTPC, Auraiya.

• However , remaining 6.6MMSCMD of lean gas is compressed in two stages ( Primary & Booster compressor) to get discharge pressure of 90Kg/cm2

• 5.5MMSCMD is transmitted through 18” Jagdishpur line to fulfill the contractual requirement of end consumers . IFFCO, Phulpur, IGFCL Jagdishpur & BHEL, besides city gas consumers at Kanpur and Lucknow. The balance approx. 1.1 MMSCMD of compressed gas is dumped to 24” Aonla line.

INTRODUCTION

AURAIYA STATION OPERATION CONDITION

MODEL CDP-416GAS HANDLED NATURAL GS

WEIGHT FLOW 142842(kg/hr)

INLET PRESSURE 46.7(KG/CM2A)

INLET TEMPRATURE 40 (oC)

INLET MOLECULAR WEIGHT 19.3

INLET (CONST PRESSURE/CONST VOL) 1.275(K AVG)

INLET COMPRESSIBILITY (Z1) 0.91

INLET VOLUME 3915(AM3/hr)

DISCHARGE PRESSURE 944.2(PSIA)

DISCHARGE TEMPRATURE 70(oC)

DISCHARGE(CONST PRESSU/CONST VOL) 1.275(K AVG)

DISCHARGE COMPRESSIBILITY (Z2) 0.930

PERFORMANCEBHP REQIUIRED AT COMPR 2283(KW)

SPEED 13120(RPM) APPROX

MAX .CONTINUOUS SPEED 13776(RPM)

OVER SPEED TRIP 14465(RPM)

HEAD POLY 4717(M)

EFFICIENCY 81.6%

SUBJECT TO A TOLERANCE OF (+,-,4%)

COMPRESSURE IS GUARANTED FOR HEAD AND INLET VOLUME

PARTS OF TURBINE• COMPRESSOR• STARTER DRIVE GEARBOX• ACCESSORY DRIVE GEARBOX• COMBUSTION CHAMBER• DIFFUSER• TURBINE

• Front of engine have air inlet bell, Drive gearbox, Starter drive gear box

• The REAR of engine have POWER TURBINE assembly.

• The TOP of engine have the BREATHER.• The power turbine may be connected with

GENERATOR or COMPRESSER according to requirement

KC5 GAS GENERATOR DIMENSIONS

WORKINF LIMIT’S OF TURBINE

WORKING OF DIFFERENT SECTIONS

COMPRESSOR CHAMBER• It is a single entry , fourteen

stage , axial flow type.• During operation air is

compressed up to 9.5 times the intake PRESSURE

• Compressor diffuser , secured to the rear of compressor casing , directs the air from the compressor rotor to combustion section

STARTER DRIVE GEARBOX• It is mounted on the top of

the air inlet chamber.• It transmits torque from the

STARTER to the COMPRESSOR rotor.

• It provides means for measuring GG speed ,separating oils from air and oil mixture

WORKING OF DIFFERENT PARTS

ACCESSORY DRIVE GEAR BOX

• Mounted on the top of air inlet.

• Receives its drive from the compressor rotor via side gear.

• The main and external scavenge oil pump assembly is mounted on the front & on rear.

COMBUSTION SECTION

• It is attached to the diffuser , incorporates , six cylindrical shaped liners.

• Here combustion liners mix AIR & FUEL , guide the hot gases into turbine unit and also , control combustion

SIMPLE CYCLE OF GAS TURBINE

THERMODYNAMIC CYCLE

PROCESS OF FUNCTIONING

• The gas turbine engine is essentially a heat engine using air as working fluid.

• As air passes through engine ,the Kinetic energy of air is increased.

• To obtain this the pressure energy first increased and then Heat energy is added in the combustion chamber.

• Heat is added at constant pressure and adding fuel

• After compression the gases is expanded through the turbine .

• And the kinetic energy is converted into the mechanical work in the PT .

• And the available as Torque at the PT shaft output spline.

WORKING PROCESS DIAGRAM

WORKING CYCLE (P-V) DIAGRAM

STARTING OF A ENGINE• Starter begins to rotate the Gas generator(GG).• The GG rpm & oil pressure begin to increase.• Governor control the Fuel valve for starting .• At 2200 GM rpm, the ignition occurs and opens the fuel shutoff

valve.• Due to ignition the GG accelerate up to 100000rpm with in the

(30-40)sec after passing through 2200 GG rpm.• At 2300-2400 GG rpm the measured temperature (MGT) should

increase rapidly to (1200-1400)degree F. • At 8400 GG rpm ,the control system turn off ignition and starter

system.

• Now the GG should accelerate normally to ideal speed in 30-40 seconds from 2200 rpm.

• If the GG rpm is less then 48 per second for the 5 second time period the system will shut down automatically.

• UP to 11,000 GG rpm the compressor bleed valves are fully open to unload compressor , at this position they begin to move to the closed position.

• APPROX at 12,600 GG rpm they are fully closed , this speed is for 59*F compressor inlet temprature (CIT).

NORMAL OPERATION CONDITIONS

• GG operate between 10,000 & 14,500 rpm.• Maximum CTIT is 1895*F• Vibrations are 1.0mil GG turbine is normal,

above this is the warning condition.• GG oil pressure is 50-60 psig .• OIL temperature at the inlet to the GG should

be less than 160*F.

COMBUSTOR AIR SYSTEM This system consists of 6 indivisible combustion linear , FUEL

(natural) GAS is continuously injected and mixed with AIR .• The AIR is compressed which is flowing from the compressor.• Once the ignition occurs , combustion is continuously go on

without igniter.• About 25% of the air leaving the compressor is utilized for the

combustion.• The remainder is used to cool the metal parts and dilute the

flame temperature to an acceptable turbine inlet temperature .

• Now the high pressure and temperature gas is passes to the TURBINE

FUEL SYSTEM• The system is mounted in the pit one of the BASEPLATE , except

filter .• The fuel filter is mounted adjacent to the base plate.• When the GG reaches 2200 rpm the fuel system stop valves SOV-

XX47X & SOV-XX46X opens .• And fuel vent solenoid valve SOV-XX48X closes.• Fuel flows through filter XXKTF-15 to the gas valve .• The fuel flows to the combustion chamber by way of the fuel

manifold.• The fuel is ignite by the spark igniter in the gas generator

combustion chamber.• As the GG passes through 8400 rpm the starter solenoid

valve ,SOV-X43X ,SOV-XX44X , AND SOV-XX45X and the spark igniters de-energise .

LUBE OIL SYSTEMS

• It is used for the lubrication of various components of the units.

• It is provided with the 2 independent oil system as given below :_____

• GAS GENERATOR lube oil system.• POWER TURBINE AND COMPRESSSOR lube oil

system

GAS GENERATOR LUBE OIL SYSTEM

• Synthetic oil is used for lubrication in this system and is stored in reservoir(XXKTV-16).

• This oil is also used to operate 5th and 10th stage compressor bleed valve actuators.

• The reservoir having storage capacity of 144 liters of oil.• Two level switches are provided in XXKTV-16 for electric signals

to main control panel to produce alarm and shutdown on lowering oil level.

• The level transducer is mounted on XXKTV-16 which sends the electronic signal to the unit control panel , which is used for indication (TI-XX64X) and actuate the alarm , and shut down switches

PROCESS OF OIL FLOW• As GG COMPRESSOR rotates , oil draws from the reservoir

(XXKTV-16) by GG lube pump , on the accessory driving housing.• Then oil passes through the foot valve (SFV-XX41XX) before

enter into the lube pump.• SFV-XX41X in addition to straining the oil , has a check valve ,

which holds oil in the line to keep the pump primed .• The pressure control valve maintains the proper pressure to GG

bearing and gears .• Now the drain oil from the bearing is removed by an external

scavenge pump on the accessory drive housing.• Another oil pump in the accessory section pumps the drain oil

from the accessory drive housing off the gas generator .• The oil from both pumps meets at a common connections and

carried by piping to an air eliminator and is piped to (AE-XX41X).

• Now air is removed form the oil by air eliminator and is piped toR-XXKTV-16 .

• And the air free oil is piped to cooler.• A motor driven fan mounted below the cooler cools the oil as it passes

through passages with XXKE-11-X. • thermostatic control valve is mounted downstream of XXKE-11-X .• A bypass line is installed across XXKE-11-X , if the scavenge oil

temperature is below140*F ,TCV-XX41X begins to close and the must flow through cooler XXKE-11X.

• The scavenger oil flows from cooler to the one of two filters.• Actuation of HV-XX41X allows transfer of oil from one filter to another . • From the filter a portion of oil returns to reservoir and a portion of oil is

placed to the hydraulic pump mounted on the accessory drive box. • The hydraulic pump discharge operates actuators of the 5th

and 10th stage compressors bleed valve.• A portion of oil from the main lube pump is piped to lubricate

the clutch in the staring pump.

• The pressure control valve down streams of the filters provide the required suction pressure head for the hydraulic pump .

• PCV-XX43X is set at 0.14kg/cm2 .• Another relief valve is mounted in the hydraulic pump

housing , this valve will open and relief the hydraulic pump discharge pressure ,if the pressure exceeds 28kg/cm2.

• And a magnetic chip detector is in the accessory drive housing of the gas generator .

• The detectors is in the discharge side of the scavenge pump.• The detectors are electrically connected to the annunciator

on the main control valve

FIRE DETECTION SYSTEM

• Two U.V detectors in each enclosure .• Two rate of rise thermal detectors in each

enclosure.• Supervisory monitor with malfunction , function

annunciation , fire detection annunciation , contacts for unit and station shutdown .

• Contacts to trigger fire extinguishing system.• There is also two high detectors in each

enclosure.

TRIPING OF AURAIYA STATION

• COMPRESSOR• Minimum pressure :- 46.7kg/cm2A• Maximum pressure :- 66.4kg/cm2A• Minimum temp :- 40*C• Maximum temp :- 70*C• Mini/max compress:-0..930• BHP required :- 2283KW• Minimum Speed :-13120rpm• Maximum speed :-14465

CONCLUSION GAIL has setup a huge pipeline over India with its easy working

condition for the employees and also with their great safety. It has set-up at least more than one back-up system so that system works with no hazardous accident.

  After summing up all I conclude this report with my utmost privilege in doing summer training with very cooperative atmosphere.