OVERHAULING REPORT OF 10MW SIEMENS MAKE STG AT STAR WIRE(INDIA)VIDHYUTH PVT LTD MAHENDRAGARH,HARYANA

BRIEF HISTORY

        M\s. STAR WIRE(INDIA)VIDHYUTH PVT LTD, Mahendragarh,Haryana, have placed order for major overhauling of  STG- 10 MW SIEMENS Make Turbine, TRIVENI Make Gear Box and TDPS Make Generator. This

10 biggest thermal power plants in India

1.Mundra Thermal Power Station

he 4,620MW Mundra Thermal Power Station located in the Kutch district of Gujarat is currently the largest operating thermal power plant in India. It is a coal-fired power plant owned and operated by Adani Power.

The power plant consists of nine generating units (four 330MW units and five 660MW units). The first 330MW unit was commissioned in May 2009 and the last 660MW unit of the plant commissioned in March 2012. The coal used for the power plant is mainly imported from Indonesia. The plant's water source is the sea water from the Gulf of Kutch.

SYLLABUS FOR BOE EXAMINATION

[As mentioned in the Notification by Government of India; Ministry of Commerce and Industry under “The Boiler Operation Engineer’s Rules,

2011”]

	A candidate in order to be qualified for a certificate of proficiency under these rules; shall, inter alia, satisfy the examiner that he—
	(a)	can calculate loads, areas, volumes, quantities and weights;

250 MW KWU GOVERNING SYSTEM

In order to maintain the synchronous speed under changing load/grid or steam conditions, the KWU turbine supplied by BHEL at NTPC Korba is equipped with electro-hydraulic governor; fully backed-up by a hydraulic governor. The

measuring and processing of electrical signal offer the advantages such as flexibility, dynamic stability and simple representation of complicated

Turbine Bearing Arrangement

FIXED PIONTS (TURBINE EXPANSION)

      The fixed points of the turbine are as follows:

      a) All the bearing pedestal

      b) Middle of the longitudinal girder of Lp turbine

      c) The thrust bearing in HP-IP pedestal.

 

TG unit CONSTRUCTION OF BEARING NO.1

BEARING

The TG unit is mounted on 1 bearing.HPT rotor is mounted on two bearings, a double wedged journal bearing at the front and combined/journal bearing adjacent to front IP rotor coupling. The IP & LP rotors have a journal bearing each at the end of the shaft. The journal bearing of IP & LP rotors are self adjusting tragspiegal bearings. The bearing pedestals are

OILING SYSTEM FOR TURBINE

1. OIL SUPPLY:-

A single oil supply line lubricates and cools the bearing, governs the m/c and operates the hydraulic actuators and safety and protective devices.

During start-up & shut-down, aux oil pump supplies the control oil. Once the turbine speed is more than 2850 rpm, the main oil pump (M.O.P) takes over.It draws oil from main tank .The lubricating oil passes through oil cooler, before can be s upplied to the bearing (Under emergency, lube oil can be supplied by a DC oil pump).Before the turbine is turned or barred,

LUBE OIL COOLER FOR TURBINE

Lubricating oil reduces friction between moving mechanical parts and also removes heat from the components. As a result, the oil becomes hot. This heat is removed from the lube oil by a cooler to prevent both breakdown of the oil and damage to the mechanical components it serves. The lube oil temperature must be maintained within a specific operating band to ensure optimum equipment performance.

Lever Safety Valve

The disadvantage of this valve is that it admits of being tempered with, and the effect of a small addition to the weight is magnified considerably in its action on the value.

Description of Lever safety valve:

It consists of a valve resting over a gun metal seat. The valve seat is fixed on a mounting block, fitted over the boiler shell. One end of the level is hinged to a rod of the mounting block, while the other end carries a weight. A short strut is placed over the valve.

Spring Loaded safety Valve

It is loaded with a spring instead of weights. Hence it is called spring loaded safety valve. It consists of a cast iron body having two branch pipes P1 and P2. Two separate valves are placed over the valve seatings, which are fixed to the top of the branch pipes. A lever is placed over the valves by means of two conical pivots.
The lever is attached to a spring at its middle. The spring pulls the lever in downward direction. The lower end of the spring is attached to the valve body by means of a shackle. Thus the

DEAD WEIGHT SAFETY VALVE FOR BOILER

Dead Weight safety valve:

IT'S mainly used for low pressures, low capacity, stationary boilers of the Cornish and Lancashire types.

The Dead Weight safety valve consists of a valve V which is made of gun metal to prevent rusting. It rests on the gun metal seat S and is fixed to the top of a vertical steam pipeP. The pipe has a flange F at the bottom for fixing at the top of the boiler shell.

A weight carrier C is suspended from the top of the boiler. It carries cast iron rings (i.e., weight W). the total weight must be sufficient to the keep the valve on its seat against the normal working pressure.

Working of Dead Weight safety valve:

When the steam pressure in the boiler exceeds the normal working pressure, it lifts the valve with its weight. The excess steam therefore escapes through the pipe to the atmosphere, until the pressure reaches its normal value.

It is the simplest type of safety valve; it is suitable for stationary boilers only, because it cannot withstand the jerks and vibration of mobile (marine) boilers. Another disadvantage of this valve is the heavy weight required to balance the steam pressure. Hence, it is not suitable for high pressure boilers.

Merits:

1)Simplicity of design
2)Gives quite a satisfactory performance during operation.
3)It cannot be easily tempered from the pressure adjustment view.
• Demerits:
1)Unsuitable for use on any boiler where extensive vibration and movement are experienced( e.g. locomotive and marine work).
2)It is not suitable for high pressure boilers because a large amount of weight is required to balance the steam pressure.

TYPE OF SAFETY VALVE'S USED IN BOILER SAFE OPERATION

Safety Valve:-

Function : The function of safety valve is to release the excess steam when the pressure of steam inside the boiler exceeds the rated pressure.

There are 4 types of safety valves:

1. Lever Safety Valve
2. Spring Loaded safety Valve
3.Dead Weight Safety Valve
4.High steam and low water safety valve

fusible plug for boiler safty

The function of the fusible plug is to put-off the fire in the furnace of the boiler when the water level falls below an unsafe level and thus avoid the explosion which may take place due to overhearing of the tubes and the shell.

Description of fusible plug:

It consists of a hollow gun metal body screwed into the fire box crown plate. A hollow gun metal plug is screwed into the gun metal body by tightening the hexagonal flange in it. There is another copper plug locked with the gun metal plug by pouring a low melting point metal (lead) into the groove provided for the same.

WATER LEVEL INDICATOR OR GAUGE FOR THE BOILER DRUM

it's very important gauge for the boiler it's function indicates the water level inside the boiler and is hence called as water level indicator. Usually two water gauges are fitted in front of boiler.

Working of Water gauge:

The water gauge shows the level of water in the boiler drum. It warns the operator if the water level goes below a fixed mark, so that corrective action may be taken in time to avoid any accident.For the observation of the water level in the boiler, the water and steam cocks are opened and drain cock is closed. The steam enters from the upper metal tube M1 into the glass tube and water enters from the lower metal

HOW TO READ PRESSURE GAUGE IN THE BOILER ?

Bourdon's pressure gauge:-
A pressure gauge is a common component in operations from various industries across the world bourdon tubes are the most common pressure measuring devices used today.
Function: 
1.To record the steam pressure at which the steam is generated in the boiler.
2. A bourdon pressure gauge in its

Boiler Mountings and Accessories

Boiler Mountings and Accessories play a very important role during the operation period we tell's you about some mountings and accessories which generally used in the boiler. boiler mountings are the machine components that are mounted over the body of the boiler itself for the safety of the boiler and for complete control of the process of steam generation.
Various boiler mountings are as under:

Types of boilers are generally used in industries now these days

Here are many types of boiler used in industries but we are mention some boiler name which is generally used for the steam generation in the industries :-

1.Fire Tube boiler 

2.Water Tube boiler 

3.Packaged Boiler 

4.Fluidized Bed Combustion Boiler (F.B.C)

5.Atmospheric Fluidized Bed Combustion Boiler(A.F.B.C)