FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
Comprehensive Technical
Training
For Sugar Mills Staff on Operation & Maintenance of
Baggase Based HP Cogeneration System
Schedule: 10th July to 13th July, 2017
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
Control oil system & It’s
Operation
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
Topics Covered.
• Introduction.
• Woodward Governor 505E.
• Electro Hydraulic convertor (I/H). HP
• Electro Hydraulic convertor (I/H). LP
• How Extraction control.
• Control valve actuator.
• Control valve (HP/LP)
• Emergency Stop valve.
• Trip valve test device.
• Start up valve (1839) & Closing valve (1830).
• Manual Operation.
• Mechanical overspeed.
• Remote turbine trip.
• Axial shift Protection.
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
Introduction
• Oil for the I/H converter is supplied through the same lube oil system which comprises of main oil pump & auxiliary oil pump which are AC motor driven.
• The oil from the discharge of the above pumps is split into two connections.
• One connection is for lubricating the turbine & generator bearings and the other is for control oil system. The connection for the control oil system passes through a duplex control oil filter.
• The Turbo Generator set is equipped with electronic governing system. The electronic speed governor maintains the speed of turbo generator set constant according to the droop characteristic.
• Additionally turbine-governing system is incorporated with protective device to protect the turbine during adverse operating condition such as over speed, low lubrication oil pressure etc.
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
• I/H Convertor 1742 is for main steam inlet control valve (governor valve)
The I/H converter, convert the (4-20mA) current signals to hydraulic pressure signal (1.5-4.5bar) there by controlling the opening or closing of the HP steam control valve (0801).
Electro Hydraulic convertor(I/H) (1742)
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
Electro Hydraulic
convertor(I/H) (1743)
• I/H Convertor 1743 is to control the turbine process extraction control valve.
The I/H converter convert the (4-20mA) current signals to hydraulic pressure signal (1.5-4.5bar) there by controlling the opening or closing of the turbine Extraction control valve (0802).
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
How Extraction control
• Extraction pressure signal sent by pressure transmitters PT 161 mounted on the turbine process extraction pipe line. After comparing it with the set value of extraction pressure, the (4-20mA) current signals is converted to the secondary oil pressure (1.5-4.5bar) by the I/H converter, thus the valve actuator can operate the turbine extraction control valve.
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
CONTROL VALVE (HP/LP).
• The control valve is regulating the steam flow base on the command from control unit to make controlled parameters( output or speed, inlet steam pressure back pressure etc). The working oil and secondary oil enter into control valve and drain oil connected to return oil line. The control valve is rotary diaphragm type. The oil relay serves as an actuator for the control valve . It converts the secondary oil pressure into stroke output with enough working capacity for operating the control valve and controlling the steam admitted into steam turbine.
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
EMERGENCY STOP VALVE
• The emergency stop valve is of closing type. The emergency stop valve consists of a spring-loaded piston and piston disc, which is connected to the valve through a spindle.
For opening starting oil is admitted to the space above the spring-loaded piston for opening the stop valve.
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
The tripping block is operated on the
occurrence of any one of the following
• Manual operation
• Actuation of over speed governor
• Drop in trip oil pressure
• Remote turbine trip
• Axial Shift Protection
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
Manual operation
• Press the handle of Trip Hand Valve (2274) for shut down of the turbine, which is on the trip block assembly. This will enable the leakage of emergency stop oil, and close the emergency stop valve.
FUNDED BY THE
EUROPEAN UNION
High Pressure Cogeneration for Sugar Sector in Pakistan
Axial Shift Protection
• Whenever the turbine rotor movement in axial direction is excessive, then a Projection on the rotor comes underneath the lever of emergency tripping device and Actuates the lever and there by tripping the turbine.