pie asset management vol i

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Asset Management: PIE

Anil Kumar AGM (Mech)-PIE: e-mail: [email protected]

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ASSET MANAGEMENT

FOR

POWER GENERATING UTILITIES

UN DER TH E PROGRAMME

PARTNERSHIP IN EXCELLENCE


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FOREWORD

The growing shortage of electricity and the commitment of the Government of India toprovide power to all by 2012 have put all the power engineers of the country at brainstorming to find out ways and means to bridge the power needs.While exploring out various options to augment the capacity performance improvementof underperforming power utilities in the country was considered to be the quickest andcheapest.

Ministry of Power, Government of India has launched a programme under the namePartnership in Excellence on 9th August 2005, wherein all leading power utilities of thecountry were asked to associate with the underperforming power utilities and provide all

necessary support to improve the performance at optimum cost.

NTPC today, with its present installed capacity of 24, 954 MW and is poised to grow intoa 46, 000 MW plus company by 2012 has already set several bench marks in powergeneration performance. NTPC, the leading power sector utility has been allocated 15power generating stations out of the 22 identified to support the programme.

With a view to adopt a uniform approach to Asset Management it was felt essential toformulate and document an integrated system for areas of operation & maintenance.The existing document developed in line with the practices being used at NTPCaddresses the issue in a comprehensive manner covering the entire area of operation

and maintenance management.The objective and emphasis of the system document is Efficient, Economic & ReliablePower generation.

It is hoped that the document shall be adopted and used by each utility in its true spirit.It may be prudent to remodel some of the practices and procedure included in theapproach document to asset management but keeping the objective focused.

NTPC on its part shall continue to support this gigantic task of work culturaltransformation and change management and provide all assistance to willing partners.This only shall fructify the aim of Partnership in Excellence and provide power in plenty

to boost the countrys economy.

Dated: June 6, 2006 (RS SHARMA)Executive Director (PIE)


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N T P C L im i t e dPARTNERSHIP IN EXCELLENCE

ASSET MANAGEMENT

FORPOWER GENERATING UTILITIES

UN DER TH E PROGRAMME

PARTNERSHIP IN EXCELLENCE(VOLUME-I)

PIE HEAD QUARTERPATNA-800 001


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ASSET MANA GEMENT

FOR

POWER GENERATIN G UTIL ITI ES UNDER THE PROGRAMM E

PARTNERSHIP IN EXCELLENCEVolume-I

CONTENTS

S.No DESCRIPTION PAGEForeword 02

ASSET MANAGEMENT-Philosophy, Concept & Approach 091. Introduction 102. Objectives 123. Corporate Technical and O&M Services (C-TOMS) 13

4. Strategic Processes 145. Operation Management

Ownership Role

Services

Equipment Care Group

Knowledge Management

Operation Performance

Technical Efficiency & Audit Management (TEAM)

6. Maintenance Management 20

Total Work Management

Preventive Maintenance

Condition Monitoring

Long Term Planning Overhaul Management

Failure & Forced Outage Diagnostics

7. O&M Safety Management 368. Resource Management 38

Spares & consumables

Tools & Plants

Knowledge & Skill Management

CORPORATE TECHNICAL AND O&M SERVICES (C-TOMS) 421. Introduction 432. Objective 433. Role & responsibilities of C-TOMS 44

Operation Performance and Efficiency Management Maintenance & Resource Management

Fuel Management

Plant Betterment & Technology Support

Enterprise resource Planning & information Technology

NTPC- Partnership in Excellence: Role 50


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OPERATION MANAGEMENT 521. Introduction 532. Objectives of Operation Management 553. Definitions 564. Calculation of Operation Parameters 61

5. Units in Use 716. Monitoring System 727. Reporting & Monitoring System 78

Daily Reporting & Monitoring -MIS

Daily Reporting of Plant Performance

Fortnightly Reporting and Monitoring of Generation Efficiency

Monthly & Annual reporting

8. Daily Performance Review Meeting 829. Monitoring by HOD (Operations) 8310. Shift Operations 8511. Role of UCB Engineers 8912. Role & responsibilities of SCE 90

13. Role & responsibilities of Operations General Shift 9214. House keeping 9315. Illumination & lighting within Station 9616. Monitoring by HOD (Water Chemistry) 9717. Role & responsibilities of Plant Chemist 9818. Role & responsibilities of O&EE Group 10219. Role of O&EE Engineer in Combustion Optimization 10520. Role & responsibilities of Fuel Management Group 10621. Functions of Environment & Ash Management Group 10822. Functions of O&M Civil 10923. Unit Forced Outage Analysis 110

Unit Trips

Boiler Tube Leakage

24. Preservation & Disposal of Log Books & Records 11425. ORT meetings 11826. P&I System Monitoring 12127. Emergency Instructions 12228. Safety Aspects in O&M 12429. Documentation 12630. Technical audits 127

ANNEXURE FORMATS: 132Daily Performance Flash Report 133Daily Generation Performance Report 134Plant Chemical analysis report 138Plant Generation Efficiency Performance Report 140Unit Forced Outage Reporting 142

Format A: Unit Trip Analysis

Format B: BTL Analysis

Agenda for discussion in ORT 148Equipment Availability Status Report 151Stand by Equipment in Service Report 153O&M SAFETY MANAGEMENT SYSTEM 154ANNEXURE FORMATS: Safety Documents 169Action plan for implementation of Asset Management System at PIE Stations 178


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ASSET MANA GEMENT

FOR

POWER GENERATIN G UTIL ITI ES UNDER THE PROGRAMM E


Volume-I I

CONTENTS

S.No DESCRIPTION PAGEForeword 02

MAINTENANCE MANAGEMENT 091. Introduction 102. Historical back drop of Maintenance 12

3. Maintenance Types 164. Definitions 195. Reliability Centered Maintenance 236. RCM Objectives 297. RCM approach 32

SHORT TERM PLANNING FOR RELIABILITY 368. Total Work Management 379. Preventive Maintenance 61

10. Predictive Maintenance 6611. Maintenance Management Organization 7412. Functions of Maintenance Management Group 7813. Functions of Mechanical Maintenance 8014. Functions of Electrical Maintenance 8115. Functions of C&I Maintenance 8216. Maintenance Quality Improvement 8317. Resource Management 8418. Maintenance Performance Indicators (MPI) 86

Abbreviations 87FIGURES:

01 Factors Affecting Maintenance Dependencies 1402 Plant maintenance Optimization processes 2603 Total Work Management Concept 3904 WOC Format 4306 WOC Flow Cycle 4807 Committed Work Plan 53

08 Plant Maintenance Optimization Basis 6409 Integrated Concept of Predictive Maintenance 7210 Organization Structure of Maintenance Management 77


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LONG TERM PLANNING & OVERHAUL MANAGEMENT 8919. Introduction 9020. Life Cycle Plan (LCP) 9321. Rolling Maintenance Plan (RMP) 9622. Station Location Annual Plan (SLAP) 101

Station Location Annual Plan Revisions 10323. Engineering Declaration 10624. Outage Category & Duration 11625. Long Term Planning & Overhaul Management Organization 12226. Long Term Planning 12227. Responsibility of LTP Management 12428. Outage Committee 12529. Functions of Outage Committee 12730. Overhaul Planning Process 13031. Outage Preparedness Index 13432. Pre-shut down Planning 13933. Pre-Over Haul Activities 16534. Overhaul Execution 16835. Outage Completion Report 179

FIGURES:11 Life Cycle plan 9512 Rolling Maintenance Plan-Preparation Flow Chart 9713 Five year rolling maintenance plan (Typical) 9814 Station Location Annual Plan (Typical) 10215 Overhaul Management Process- Support System 12916 Overhaul Planning Process of Unit Overhaul 133

ANNEXURE FORMATS:SLAP Revisions 104Engineering Declaration 112Pre-outage Performance Evaluation status Sheet 166

Daily OH Exception reporting Format 176. PLANT MAINTENANCE OPTIMIZATION 185PM Schedule & Condition Monitoring Activities

Boiler & Aux. Equipments (Typical) 202

Turbine & Aux. Equipments (Typical) 230

Balance of Plant Equipments 233

Electrical Equipments (Typical) 250

C&I Equipments (Typical) 263

Coal handling Plant Equipments 273

Standard Work Module for Overhauls

Boiler & aux.(Typical) 280

Turbine & aux. (Typical) 290

Balance of Plant Equipments 300 Electrical Equipments (Typical) 305

Coal handling Plant (Typical) 309

Maintenance Quality Check & Protocol (M-QCP) Sheets (Typical) 313Re-commissioning Check Sheets (Typical) 344


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ASSET MANAGEMENT

FOR POWER GENERATING UTIL IT IES

UN DER PIE PROGRAMME

PHILOSOPHY , CONCEPT & APPROACH


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1.0 INTRODUCTION:

NTPC, since its inception, in Nov. 1975 has set several bench marks of power

generation performance at national level. Today with the present installed

capacity of 24249 MW including the capacity of joint venture (19.51% of countrys

total Installed Capacity) it generated 170.88 BU to meet 27.60% of national

power supply. The sustained performance level could be achieved due to

scientific and professional approach to Operation & Maintenance Management

adopted at NTPC.

Government of India, Ministry of Power has launched a programme on August

9th, 2005 with the objective of performance improvement of various power

generating plants located across the country under different power utilities. The

programme aptly named, Partnership in Excellence involves countrys major

power utility NTPC Ltd. as the lead player besides involving other key

performers e.g. Tata Power, APGENCO, GEB & RRVNL.

NTPC has been entrusted with 15 stations comprising of 51 generating units of

varying size ranging from 30 MW to 210 MW with a total capability of 5925.5 MW

for the turnaround in performance. The desired objective is aimed to be achieved

through two tier approach to change management which involves:

a) Management System through Expertise & Systems Engagement (EASE).

b) Equipment/System rehabilitation through quality overhauls & technical

upgrade.


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With a view to adopt a uniform systems approach, it has been felt essential to

evolve a documented Asset Management Philosophy for all such power

generating units covered under the Partnership in Excellence (PIE) plan.

The proposed Asset Management Philosophy is based on requirements of

equipments using age old technology; control systems and considering aspects

of obsolesce yet meeting all safety requirements.

The proposed asset management philosophy shall aim to achieve the objective

of phased improvement with a focus on efficient & economic power generation

through reliability centered maintenance approach.

The document is exclusively meant for power utilities covered under the

programme Partnership in Excellence and contains general guidelines.

Suitable changes & adjustments may be required to suit vocational needs.

However it is desirable that such changes are done with due discussion and

consent of concerned executive in NTPC-PIE group for clarity & purposeful

effectiveness.

The present PIE- Asset Management Philosophy shall be used as a guideline

facilitating the defined objectives and not as mandatory & restrictive rules for

obtrusion.


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2.0 OBJECTIVES

The PIE- Asset Management Philosophy shall focus on achieving the broad

objectives of restoration of power generating units at a sustained & high level of

performance.

The philosophy shall focus on achieving the broad objective of efficient and

reliable power generation in the area of Operation & Maintenance through

standard guidelines so as to adopt a uniform commercial approach to achieve

the following:

(i) Maximum plant availability

(ii) Maximum generation

(iii) Optimum efficiency of generation

(iv) Optimum reliability of plant/equipment

(v) Low down time of plant/equipment

(vi) Optimum maintenance cost

(vii) Optimum resource utilization

(viii) Maximum safety at works

(ix) Optimum inventory management of fuel, spares & materials

To achieve these aims PIE-Asset management Philosophy shall adopt an

integrated Operation & Maintenance Management System.


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3.0 CORPORATE TECHNICAL AND O&M SERVICES

(C-TOMS) GROUP:

In order to ensure that the organizations objective of Economic, Efficient &

Reliable Power Generation is met successfully it is essential to create a Central

Technical and O&M Services (C-TOMS) Group at each utility head quarter.

A similar structure has earlier been recommended by GOI appointed Srinivasan

Committee on Modernization of Maintenance Practices in Large Thermal Power

Stations in March 1986.

Similar concept is being practiced by successful utilities. The concept has been

revisited in the present context of GOI-PIE programme and a suggestive

improved model is enclosed elsewhere in the document.

4.0 STRATEGIC PROCESSES:

The proposed PIE- Asset Management Philosophy aims to achieve the objectivethrough an integrated approach to O&M process and shall cover the following

systems.

a) Operation Management System.

b) Maintenance Management System.

c) Safety Management System.

d) Resource Management System.

Periodic review and re-examination of PIE-Asset management Philosophy

containing O&M systems shall be carried out at an interval of two years or as the

need be. Such review must be carried out in consultation with NTPC-PIE group.


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5.0 OPERATION MANAGEMENT SYSTEM

The Operation Management System is structured around the power generation

programme of the plant so as to achieve maximum continuous generation at optimum

efficiency with maximum safety and minimum cost.

The main aspects of operation management system shall be as under.

5.1 OWNERSHIP ROLE:

(i) Operations shall be directly responsible for the power generation plansand hence it shall have the ownership role. It shall be accountable to all

constraints in power generation as per the schedule.

(ii) As an owner, operations shall have an effective involvement in the Total

strategic Planning Process related to generation and maintenance.

5.2 SERVICES:

(i) Operations shall requisition the services of concerned maintenance

department after physical inspection of the defective

equipment/component and reasonable diagnostics of the defect, its nature

and its location.

(ii) The term Emergency pertaining to requirement of the maintenance

services shall be limiting in its implication only in following conditions: -

a. Immediate hazard to environment including human life & plantassets

b. Immediate loss of full generationc. Potential loss of generation beyond 20% of unit size


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All the remaining maintenance requirements shall be classified under A &

B category as defined elsewhere. Emergency Jobs (E category) shall be

addressed to by concerned maintenance group on round the clock basis

till its satisfactory completion.

(iii) Operations shall be fully authorized to unilaterally deny the permit for work

or recall the permit for work, if issued, at short notice on reasonable

grounds of emergency related to generation or safety of plant /personnel.

5.3 EQUIPMENT CARE GROUP:

(i) Operations shall prepare the Equipment Change over Schedule in

a manner such that it integrates with the Preventive Maintenance

Plans. This is to ensure uniform operational loading of the

equipments as also their availability for maintenance as per the

plan.

(ii) Operations shall manage an Equipment Care Group (ECG). This

group shall be responsible for the following functions:

To ensure equipment cleanliness and upkeep

To ensure good plant area house keeping

To ensure adequate plant area lighting including emergency

lighting


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(iii) Responsibility of on-load testing of protection & interlocks including

testing of fire protections & fire detection devices and protection

systems for hazardous work conditions e.g. eye washer, chlorineleak detection system etc.

5.4 KNOWLEDGE MANAGEMENT:

To ensure efficient and commercial operation practices a continuous

knowledge management programme is essential. Such a programme for skill

up-gradation and development shall be coordinated by HOD (Operations). This

shall be structured with inputs from available OMIMs, P&I diagrams, flow

diagrams and technical specifications of the equipments etc. All such OMIM

shall also be available with operation and maintenance staff in hard as well as

soft copies and on local area network. These orientation & awareness

programme shall be continually updated on the basis of experience, unit forced

outage analysis and new technological developments.

5.5 OPERATION PERFORMANCE:

(i) Head of O&M as well as the station head shall monitor and review the

following performance parameters on daily/weekly basis:

Generation performance parameters

Efficiency performance parameters


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(ii) The intent of all such reviews and deliberations in daily plan meeting with

other section heads shall be Efficient, Economic and Reliable Power

Generation of the previous day and to evolve action plan for the present

and the next day.

(iii) Reasons of variance in generation performance as well as energy

efficiency shall be deliberated in daily plan meeting. Concerned groups

shall work upon the plan of action so decided to prevent such recurrences

and to achieve better efficiency.

(iv) Station Head and Head of O&M shall review and monitor monthly

performance of generation & energy efficiency, forced outages and other

related parameters in full details with root cause analysis and action

plan/action taken.

(v) Such a review shall be done along with Operation Review Team (ORT)

in a meeting to be carried out by Central O&M Services (COMS) of the

Utility in association with NTPC-PIE HQ services.

5.6 TECHNICAL EFFICIENCY AUDIT MANAGEMENT:

(i) An annual technical audit shall be carried out by a cross functional

team drawn from O & M personnel working at different stations alongwith Corporate Technical and O&M Services (C-TOMS) Group of the

Utility in association with NTPC-PIE HQ services.


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(ii) The objective & intent of all such technical audit shall be as

follows:

To review the operational regime of the unit and variance

To assess the performance efficiency of the unit

To identify areas of generic problem or constraint areas likely to

affect the performance of unit/station.

To suggest remedial action plans addressing these areas

To identify areas of betterment & evolve suitable action plans

Safety aspects of O&M areas and to suggest corrective actions if

any

Compliance to statutory requirements of the environments,

electricity act and Indian boiler regulations etc. Analysis of non

compliance and remedial action plan.

Protections & Interlocks (P&I) not kept in service during the past

months and analysis of the same

System approach in O&M Practices and deviations if any, with

reasons for such deviations and recommendations if such

deviations in practices call for a permanent/temporary changes in

the system.

(iii) Major aspects which shall be under audit review for coal based

stations shall be as under:

Main steam pressure/temperature variance

HRH/CRH pressure/temperature variance

Back pressure across condenser (vacuum).

CW temperature variance

Head transfer in FW System (across HPH)


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Water chemistry controls

Boiler metal temperature variance

Mill condition for out put & fineness

Carbon in bottom/fly ash

SADC operation & control

Oxygen in flue gas

Heat transfer across air pre-heaters

Flue gas exit temperature

Fuel Quality and its effect

Heat Rate including specific fuel consumption

Aux. Power Consumption

Emission & effluent disposal wrt environmental norms (e.g.

Sox, NOx, SPM etc)

Operation practices (Machine startup/ loading/ shutdown

parameters & processes)

Protections by passed or not in service and restoration plan

Unit trips analysis with action plan.

Major equipment outages & non-availability status and action

plan.

Equipment failures leading to partial/ total generation loss and

action plans.

Generation Performance wrt declared capability and grid

conditions

Status of emergency support system e.g. DC system & fire

protection system etc

Safety aspects, Emergency handled and lessons learnt

Fuel stock and action plan

Spares & material criticality analysis and action plan

Areas of high consumption pattern of materials and theiranalysis


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All variance shall be analyzed wrt PG test values/ best

achieved values with action plan to reduce/eliminate negative variance.

(iv) Corporate Technical and O&M Services (C-TOMS) Group of the Utility

shall be responsible for coordination and implementation of all action

plans arising out of such technical audits and shall issue a quarterly

ATR.

6.0 MAINTENANCE MANAGEMENT SYSTEM

Maintenance Management System is structured around the equipment and plant

maintenance needs to ensure maximum availability and reliability at minimum

cost and shall be based on the concept of Total Work Management (TWM)

The major aspects of the maintenance management system shall be as follows:

6.1 TOTAL WORK MANAGEMENT:

(i) Maintenance Management system shall be based on the concept of total

work management. The maintenance strategy shall ensure distribution of

maintenance workload uniformly through the year. All maintenance jobs

shall be initiated through a work order card, monitored till completion and

documented into history system.


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(ii) Maintenance functions shall be fully responsible for providing services so as

to facilitate operations meet the power generation plans. Maintenance shall

keep adequate resources of men, spares, material and T&P to ensure the

above function but in a most cost effective manner.

(iii) Engineering functions of maintenance e.g. equipment fault diagnostics,

identification of resource requirement, resource management, work

execution and work quality shall be the responsibility of maintenance

executives.

(iv) Planning functions of maintenance e.g. job planning and coordination for

scheduling of work, timely availability of identified resources to maintenance

and MIS as per the requirement of different levels of management use shall

be the responsibility of maintenance planning engineer.

(v) A concept of opportunity-based maintenance shall be evolved and applied

on such equipment having no redundancy. The preventive maintenance on

equipments having no redundancy shall be taken up during minor, medium

or major overhauls.

6.2 PREVENTIVE MAINTENANCE:

(i) PM Schedule: Station shall prepare a schedule of preventive

maintenance which in its early stages shall incorporate equipment

checks based on manufacturers recommendations and station

experience under the following categories:


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(a) Weekly, fortnightly or monthly in service/walk down checks,

in addition to daily operations checks. Such checks shall not

call for stoppage of the equipments

(b) Monthly, Quarterly, Half yearly & yearly checks which may

call for equipment outage/isolations

(c) Lubrication schedule calling for complete replacement based

on manufacturer recommendations

(d) Overhaul & servicing checks at periodic intervals as

recommended by the manufacturer.

(ii) Reviews of Preventive Maintenance Schedule:

The preventive maintenance schedule so developed shall be updated once

a year based on experience on equipment behavior gained by the area

O&M engineer, periodic interaction with the equipment manufacturer as well

as the experience gained by other power utilities having similar equipments

with matching duty conditions shall also be taken into account while carrying

out the Plant Maintenance Optimization (PMO) activity for updating the

preventive maintenance schedules as well as overhaul planning.

The intent of all such annual review of PM Schedule shall be to evolve the

optimum maintenance needs specific to equipment in a particular duty

condition at a specific location.


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The equipment specific approach rather than a general approach shall avoid

excessive or too little maintenance. All reviews of PM Schedules shall be

aimed at Condition Based Maintenance (CBM)

(iii) Equipment Changeover Schedule:

In order to ensure that preventive maintenance and condition monitoring

schedules are effective i.e. all such equipments are available in desired

state of health; an Equipment Changeover Schedule (ECS) shall be

prepared by operations in consultation with maintenance and maintenance

planning. ECS schedule shall be coordinated for implementation by

maintenance planning.

Thus maintenance planning shall ensure that equipments having

redundancy do not call for any abrupt stoppage/start of the equipment for

the purpose of implementation of preventive maintenance and condition

monitoring schedules.

(iv) Execution of PM Schedules:

Maintenance planning has to further ensure that preventive maintenance

and condition monitoring schedules of all disciplines (Mechanical, Electrical

and C&I) are integrated into single equipment isolation to the extent

possible. Maintenance planning shall therefore ensure that different

departments execute their maintenance work plan during a single isolation

and separate isolations/shutdowns are not requested.


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6.3 CONDITION MONITORING:

(i) Condition Monitoring Schedule:

As a first step towards condition based maintenance it is essential

that Condition monitoring of all critical equipments is initiated in the first phase

and later extended to all other non-critical equipments. A condition-monitoring

schedule shall be developed for all critical equipments and executed upon by a

condition-monitoring group at each station under maintenance planning.

The condition-monitoring group shall equip itself with necessary expertise so

as to undertake behavioral trend analysis of critical equipments.

This group shall gradually develop its expertise to work as a predictive

maintenance and diagnostics group. The group shall attempt to predict likely

failure pattern in qualitative and quantitative terms. It is likely that initially these

forecasts may not be very accurate. But it is envisaged that over a reasonabletime frame expertise shall be developed to with a larger degree of confidence

affecting saving in maintenance cost.

(ii) Condition Monitoring Techniques:

Various available techniques and latest technology shall be used for condition-

based maintenance so as to impart a good degree of reliability and low

maintenance.


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Different conditions monitoring techniques shall be used in an integrated

manner to compile conditioning monitoring database for evaluation of the

equipment condition and behavioral trend.

The initial integration of condition monitoring shall include the following:

Vibration Spectrum: Vibration and behaviour trends of all critical

rotary equipments through on/off line vibration measuring

instruments.

Lube Oil Spectrum/Analysis: Routine test of lube oil for moisture

impurities and acidity, wear debris analysis etc. shall be carried out

to determine oil condition and need for centrifuging or supplement

with additives for full life usage.

Bearing Condition Monitoring & Analysis: Monitoring of

conditions such as Lubrication, Temperature, Noise, SPM etc shall

be used to predict condition of anti-friction bearings.

Acoustics & Noise Surveys: To defect any abnormality in the

equipment as also the hazard to health of personnel working.

Infra Red Thermography: Infrared thermo-vision techniques shallbe used to detect hot spots on critical equipments e.g. SWY

transmission lines, Transformers, Steam valve leaks, bearing

condition etc.

Motor Current Analysis: Motor current analysis shall be carried

out on critical electrical motors and data used to evaluate their

performance and general condition.

Transformer Condition Analysis: Dissolved gas analysis on

transformer oil along with IRT techniques shall be used at a pre-

defined periodicity to carry out transformer condition analysis and

predict the behavior pattern so as to take timely action and avoid

costly breakdowns.


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TAN-DELTA: Test shall be carried out on critical electrical

equipments and data used to evaluated their long-term

performance

Pressure Parts Survey: Boiler pressure parts shall be monitored

for erosion and rate of wear during overhauls. The inspection shall

be carried out by area maintenance engineer along with a

representative of quality team.

Wear Rate Survey: Mill components especially the grinding

elements shall be regularly monitored for wear rate for every 1000

MT of coal ground. This data shall be used to make life extension

action plan for grinding components of the coal mills, in addition to

component replacement plans.

Turbine Parameters: Number of starts, grid frequency, MS

pressure and temperature, First stage pressure, Condenser

vacuum/Back pressure etc.

Boiler Parameters: Boiler metal temperature variance. Trips &

thermal stress, Water Chemistry, FW heat transfer across HPH etc.

Boiler Combustion: Oxygen, flue gas exit temperature, SADCcontrols, carbon in ash, soot blowing frequency, slagging & flame

condition etc.

Unit Forced Outage Analysis: All unit tripping due to P&I shall be

analyzed for root cause and corrective action plan evolved for

implementation on techno-economic basis.

Milling System Performance: Mill/ coal fineness, Coal quality, PA

flow & Mill outlet temperature etc.


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6.4 LONG TERM PLANNING: (LTP)

(i)Life Cycle Plan (LCP) & Life Extension Plan (LEP):

It is desirable that each utility develops a Life Cycle Plan (LCP) for the

entire life cycle of 25-30 years for each of its units which are new or have

operated for a lesser period incorporating major replacement plans.

The Initial life cycle plan shall be developed by Corporate Technical and

O&M Services (C-TOMS) Group based on the utility experience in

consultation with OEM & experience of the leading power generating

utilities as well as NTPC-PIE head quarter.

Since most of the PIE operating units are very old and already have run for

above 25-30 years, it is essential to study the unit life condition based on

their past part load operation to ensure that all repair and maintenance

plans for Life Extension Plan (LEP) are adequately identified based on cost

benefit evaluations (CBE). Station shall prepare a life extension plan (LEP)

for each of its unit based on unit behavior; RLA studies technological

developments and anticipated needs of renovation and modernization.

All such life extension plans shall be on the basis of cost benefit analysis

and shall be evaluated by the Corporate Technical and O&M Services (C-

TOMS) Group of the Utility in association with NTPC-PIE HQ services.


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These plans shall cover replacement of high value components and /or

equipments likely to become redundant due to service conditions or

anticipatory technological improvements.

Such plans shall also indicate likely trend of replacement of the

equipment/parts which are likely to fail before the life expectancy of the

entire unit such as super heaters, re-heaters, high pressure valves, safety

valves, gear reducers, ash disposal lines, slurry pumps, chemical piping,

resins, conveyor belts and drives, coal crushers, turbine rotor blades,

turbine bolts, boiler feed pump rotor, H.P. heater coil, H.T. motor,

transformer, switch gears, cables etc. Input for such plans shall be the

experience of the industry with similar equipments/ suppliers and the

technological advancements taking place world wide.

The objective is to make a long term engineering assessment of the

equipment/component and plan the budget as well as resources to take up

such jobs.

(ii) Station Rolling Maintenance Plan:

Each station shall prepare a rolling plan for each unit overhaul. The station

rolling maintenance plan (RMP) shall be made for a minimum period of

five years.

Rolling Maintenance Plans shall have a consolidation of five year and

shall be a derivative of the life cycle plan (LCP) & life extension plan (LEP)

of the station. The plan shall have projections of five years.


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The first two years shall have a fairly accurate assessment of major jobs

to be taken up along with work duration and budget requirement whereas

subsequent three years shall be indicative. These plans shall be reviewed

/updated every year to project the assessment for the next five years in a

rolling manner.

This plan shall be updated every year and used to anticipate requirement

of resources e.g. spares and material, skill and expertise, finances &

budget projections. These plans shall be updated every year in April in a

rolling manner. These plans shall be examined by the Corporate Technical

and O&M Services (C-TOMS) Group of the Utility in association with

NTPC-PIE HQ services.

(iii) Station Location Annual Plan:

Each station shall prepare station location annual plan for each unit

derived out of its rolling plan. This plan shall be used for final planning as

well as organizing the resources e.g. spares and material, skill and

expertise, finance & budget provisions and execution of the plan.


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6.5 OVERHAUL MANAGEMENT: (OHM)

(i) Planned & Forced Outages:

Only unit outages budgeted under the station annual plan and approved

by the station management as well as the grid management/statutory

authority shall be termed as Planned Outage. All other outages shall fall

under the category of forced outages.

(ii) Overhaul Category:

The category of overhaul for thermal units based on frequency and

duration of planned unit outage shall be as follows:

Minor Overhaul: Any budgeted outage not exceeding seven

days.

Medium Overhaul: Any budgeted outage of seven days or

more but of not more than twenty five days duration.

Major Overhaul: Any budgeted outage exceeding twenty

five days duration.

(iii) Overhaul Duration:

For the purpose of calculating the planned outage duration, period from

bar to bar (de-synchronization to re-synchronization) shall be considered.

Extension of planned outage on account of surprise defects and

unforeseen or force-majures shall be accounted under unscheduled

extension of planned outage.


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For thermal generating units following duration shall be considered:

S.No. Unit Size (MW) Work category Overhaul

Duration

(days)

01 Below 100 MW size Boiler statutory Inspection 15 days

02 100 MW & above but

less than 200 MW size

-do- 20 days

03 200 MW & above -do- 25 days

04 Below 100 MW size Turbine overhaul

(all cylinders)

30 days

05 100 MW & above but

less than 200 MW size

Turbine (one or more

cylinders at a time)

35 days

06 200 MW & above Turbine (one or more

cylinders at a time)

45 days

These are initial time frames which shall be improved upon as the

experience of PIE stations grow and all efforts shall be made to match

national levels of performance benchmarked by NTPC.


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(iv) Engineering Declaration:

An engineering declaration of each unit planned for an outage shall be

prepared by the station maintenance planning defining the objective of

outage, work plan, present performance of the unit and anticipated

quantitative improvements in performance, availability and reliability.

Engineering declaration shall also justify expenditure in terms of projected

gains. The document shall be submitted in January each year to

Corporate Technical and O&M Services (C-TOMS) Group of the Utility

which shall be examined by them in association with NTPC-PIE HQ

services.

(v) Maintenance Quality Check & Protocol Sheets:

Station maintenance planning group shall coordinate to develop

maintenance Quality Check & Protocol Sheets (MQCP) in association with

station area maintenance engineers. These QCP shall have the category

of checks also defined. These MQCPs shall be used during all major PM

jobs including Equipment or Unit Overhauls. The primary responsibility of

work and it quality shall rest with the area maintenance executive.


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6.6 FAILURE & FORCED OUTAGE DIAGNOSTICS:

(i) Unit Forced Outage: All unit forced outages shall be categorized under

following three categories.

Boiler tube leakages

Unit tripping due to protections & interlocks

Grid disturbances

(ii) Equipment Failure Analysis: All major equipment failure shall be

investigated and analyzed in detail and action plan evolved to prevent

such recurrence. Initially following equipment/system may be covered for

failure analysis.

Steam Generator

Main turbine

Turbo generator Air pre-heater

ID/FD/PA fans

Milling system

Boiler feed Pump

Condensate Extraction Pump.

C.W. Pumps

Compressors BFP drive turbine

Transformers (GT/ST/UT/IBT)

HT Motors


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The above list is suggestive and not mandatory and may have additions

and deletions on the basis of requirement at each station.All such failures analysis shall be carried out by a diagnostic committee

formed out of the available experts at station level with members drawn

from different disciplines e.g. operation, boiler maintenance, turbine

maintenance, electrical maintenance, C&I maintenance, chemistry and

maintenance planning as well as operation performance and energy

efficiency group. All analysis shall contain the details of previous such

recurrence over the past three years and remedial actions taken, if any.

(iii) Boiler Tube Leakage Analysis: Boiler Tube Leakage (BTL) shall be

investigated and analyzed in detail and action plan evolved to prevent

such recurrence. Boiler Tube Leakage (BTL) shall be investigated and

analyzed by the station and remedial action plans shall be integrated with

unit overhauls for major replacement of pressure part components to

prevent boiler tube leakages. Wherever required this group shall take the

help of NTPC R&D / IIT or other test labs for the purpose.

(iv) Unit Trip Analysis: All unit trips shall be investigated and analyzed in

detail and action plan evolved to prevent its recurrence. Such action plan

shall be integrated with unit overhauls or opportunity based maintenance

plans so as to achieve the target of zero tripping.

(vi) Failure and forced outage report shall be submitted by the committee

within a week of restoration of the equipment/unit to station management

for onward submission to Corporate Technical and O&M Services (C-

TOMS) Group of the Utility for review and evaluation in association with

NTPC-PIE HQ services.


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Based on all such failure analysis each station shall organize every six-month

awareness and knowledge sharing workshops, wherein action plan

implementation shall also be discussed & deliberated.

(v) Plant betterment plans: Plant betterment plans shall be evolved

out from unit outage analysis and other major equipment failure

studies. Plant betterment plan shall also focus on technical

obsolescence. The aim of such plant betterment plans shall be to

achieve enhanced reliability and use of new and cost effective

technology.

(vi) RLA studies & Life Extension Plans (LEP): Residential life

assessment studies need to be initiated in a planned manner and

necessary data bank created from base material or the time of first

unit/equipment overhaul.

A few of such aspects of RLA studies that need to be incorporated are as

follows:

Creep measurement of high temperature/pressure lines e.g.

MS, HRH, and CRH etc.

Creep measurement of high temperature/pressure pressure

parts headers.

Creep measurement of high temperature fasteners e.g.

turbines, ESV/IV & CV/GV fasteners and spindles etc.

Copper Pickup Test of pressure parts shall be carried out

during each major overhaul, especially where Copper or its

alloy is use in steam circuit.


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In situ Oxide thickness (IOT) measurement on steam coils.

Weld joint inspection on critical areas e.g. MS, HRH, CRH

steam lines, boiler drum, turbine chest, super heater bi-

metallic joints etc. shall be carried out using NDT

techniques.

Microstructure replica shall be taken at select places e.g.

turbine casings, steam chest gas turbine combustion

chamber, steam generator headers etc.

Natural frequency measurement of turbine blades

RLA study database shall be used to define maintenance needs and life

extension plans leading into useful renovation & modernization.

7.0 O & M SAFETY MANAGEMENT SYSTEM

(i) All power generating plants and machinery are subjected to fluid flow

at high velocity with high pressure and temperature, flow of high

current and voltage, handling of bulk chemicals and gases as well as

exposure to radiation hazards. O&M Safety Management System

shall have a focus on handling of such situations arising out of all

such conditions of plant & machinery in a manner that ensures a

continual safe work environment to men, machine and surrounding

environment and its habitat.


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(ii) The system of permit for work shall be therefore well defined,

authenticated and approved to meet the above requirements of

safety of machine, environment & personnel. Different safety

documents to be put in use shall be under following categories:

LWC- Limited work certificate: shall be applicable in situations

where the equipments is in service or in standby mode and such

standby equipment can start any time without prior intimation.

Observance of predefined precautions is an essential condition.

PTW-Permit to work: shall be applicable in situations where

equipment is fully isolated and certified by operations. Observance

of predefined precautions is necessary.

PTW with HWP (Hot Work Permit): shall be applicable in

situations where working maintenance personnel are allowed to

carry out welding and other such jobs, which have a potential fire

hazard. Observance of predefined precautions is necessary as also

preparedness to prevent any fire or untoward incident.

ROMP-Restoration of Motive Power: shall be applicable insituations where working maintenance personnel are allowed of

restoration of motive power by authorized person for trial run &/ or

adjustments during the maintenance work. Observance of

predefined precautions is necessary.

SFT- Sanction for Test: shall be applicable in situations where

working maintenance personnel shall be with authorization to

perform specified test after observing necessary precautions on a

live or isolated system.


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8.0 RESOURCE MANAGEMENT SYSTEM

Success of O & M systems shall depend upon the timely availability of

resources, their efficient use & effective management.

In order to address these aspects it is essential that a Corporate technical

and O&M Services (C-TOMS) Group is created at each utility corporate

office. This group shall be focal point for achieving the generation

objectives of the organization. The details of such a group and its role and

responsibilities are defined elsewhere in the document. Also it is essential

that the support services e.g. purchase contracts, finance & human

resource groups are also sensitized to the organizations generation plan

and its associated requirements.

The various practices and procedures need to be formulated with this sole

objective. The aspect of resource management shall also comprise the

following:

(a) Spares & Consumable Material Management

(b) Knowledge & Skill Management


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8.1 SPARES & CONSUMABLE:

(i) Spares management shall call for identification of spares,

equipment wise & developing the full specification. The category of

spares common to more number of equipments can be thereafter

evolved while retaining link with the individual equipments.

(ii) Equipment spares with propriety cases need to be procured under

a pre-agreed rate contract to have minimum inventory yet ensuring

timely availability of spares. Such purchase shall be governed

under pre-defined and pre-approved purchase process.

(iii) For spares & materials which are available with alternate/ more

vendors, procurement need to be rationalized under a pre-tendered

rate contract to have minimum inventory yet ensuring timely

availability of spares.

(iv) Management of common use and fast moving Consumables &

other materials shall call for identification of estimated annual

consumption at the station. Item in this category can be put on rate

contract for quick response deliveries. Continued procurement from

such vendors shall depend upon performance evaluation by each

such station in their respective area.


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8.2 TOOLS & PLANTS:

(i) Tools & plants form an integral part of the O&M processes. It is

therefore essential to have T&P of good quality and in good

condition. Wrongful use of T&P must be discouraged as it may lead

to poor quality of work as well as may create unsafe work

conditions.

(ii) It is always desirable to have the latest tools, tackles & plant

services as this helps eliminate long and prolonged outages. It

should be considered as an investment in better methods, practices& procedures. Otherwise also a good methodology shall be to work

out cost economics of the investment in T&P.

8.3 KNOWLEDGE AND SKILL MANAGEMENT:

(i) To encourage knowledge based approach amongst power

professionals of PIE stations area specific workshops and technical

journals on feed back sharing can be evolved.

(ii) To keep abreast of latest technology as well as to keep Operation &

Maintenance personnel afresh, training & refresher programs need

to be organized. These training programmes could be structured in-

house or with the support of external expert faculty or throughnational level institutes involved in training in power &

management. A continuous interaction also need to be maintained

among all levels of employees for dissemination of knowledge,

identification of training needs etc.


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(iii) For overhauling jobs enlistment of vendors/agencies can be done

based on periodic evaluation & past work performance in terms of

quality, time duration & reliability.

Suitable procedure for evaluation of work performance of such

enlisted vendors based on pre-defined/pre-determined parameters

needs to be evolved to encourage quality work.


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CORPORATE TECHNICAL AND O&M SERVICES

(C-TOMS)


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1.0 INTRODUCTION:

In order to ensure that the organizations objective of Economic, Efficient &

Reliable Power Generation is met successfully it is essential to create a central

O&M Services group at each utility head quarter.

This has earlier been recommended by GOI appointed Srinivasan Committee on

Modernization of Maintenance Practices in Large Thermal Power Stations in

March 1986.

The concept is being practiced by successful utilities. This has been revisited in

the present context of GOI-PIE programme and a suggestive improved model is

presented in this document.

2.0 OBJECTIVE:

The objective of the creation of a Central O&M Services Group at all PIE Utilities

is to ensure that the organizations objective of Economic, Efficient & Reliable

Power Generation is met successfully.

Most the power generating units of these stations are over 25-30 years old and

hence need a well structured technical support to ensure that power generation

plans of the organization are met without interruptions, while ensuring that O&M

needs are met in a cost effective manner and without any delay .


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The proposed group shall have roles and responsibilities as defined in

subsequent para though not limiting. The group shall be headed by a chief

executive reporting directly to Director (Generation/ Operation/Thermal) as the

case may be who in turn reports direct to CEO of the power utility.

3.0 ROLE & RESPONSBILITIES OF THE C-TOMS:

A centralized Corporate Technical and O&M Services (C-TOMS) group shall be

structured so as to perform following broad spectrum of key functions. This shall

cover though not limiting to the following to ensure that the organizational

objective of Efficient, Economic & Reliable Power Generation is continually met

1. Coordinate all O&M requirements of the different stations of the

organization starting from the conceptual design stage to erection,

commissioning to efficient, economic & reliable power generation.

2. Development of O&M Management Systems

3. Installation & implementation of all such systems.

4. Periodic review of the systems effectiveness and suitable improvements

& amendments

5. To ensure technical expertise and skill engagement as well as engineering

support for plant betterment, improvements and modernization plans overthe life cycle of the units/plant.


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The central Corporate Technical O&M Services (C-TOMS) group shall cover the

following areas

1. Operations Performance & Efficiency Management System

2. Maintenance & Resource Management System

3. Fuel Management System

4. Plant Betterment & Technology Support System

5. Information Technology & Enterprise Resource Planning

The role & responsibilities of each group, though not limiting, is summarized

below

OPERATIONS PERFORMANCE & EFFICIENCY MANAGEMENT SYSTEM

The group shall be responsible for the following:

1. Development of standard operations performance & efficiency monitoring

systems

2. Creation of adequate awareness at different level about the same and

ensure implementation of these systems at each stations with suitable

location changes with due approval

3. To evolve safe operating procedures and check list/ sheets of

commissioning, re-commissioning, operation, start up and shut down of

the plant at all levels.


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4. To ensure that all equipment/plants are thoroughly checked and made to

operate at guaranteed performance levels in a safe and effective manner.

5. Preparation of safety manuals incorporating the safe operation & isolation

procedures to ensure safety of plant, personnel and environment during all

times of O&M activities.

6. Monitoring the variance in efficient operation & identify reasons. To

introduce the world wide best practices which facilitate energy efficient

operation

7. To set norms of water chemistry performance and to ensure that water

chemistry is maintained to desired quality at all its operating plants.

8. To provide assistance and to ensure adequate and effective

implementation of operation performance & energy efficiency

management system incorporating activities of water chemistry

management.

MAINTENANCE & RESOURCE MANAGEMENT SYSTEM


1. Development of standard maintenance & resource management system

with focus on short term as well as long term maintenance needs and

resource requirements.

2. Creation of adequate awareness at different level about the same and

ensure implementation of these systems at each stations with suitable

location changes with due approval

3. Monitoring the maintenance performance indices. To introduce the world

wide best practices which facilitate safe & quality maintenance practices to

impart reliability to equipment service condition.


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4. To implement systems for optimization of maintenance needs

incorporating a judicious mix of preventive, corrective and predictive

maintenance as well as condition based overhauls.

5. To provide assistance and to ensure adequate and effective

implementation of maintenance management system incorporating

activities of short & long term, overhaul management and condition

monitoring.

FUEL MANAGEMENT SYSTEM


1. To ensure effective coal coordination between the organization, coal

companies and transporter so that adequate quantity of coal is always

available at the stations to meet the generation plans.

2. To devise & implement proper test procedures of coal sampling and

quality measurement to ensure low cost of fuel input.

3. To coordinate with different central and state agencies such as railways

etc to ensure cheaper mode of coal haulage & transport

4. To coordinate with railways & stations to ensure adequate loading/

unloading to avoid demurrage etc.


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PLANT BETTERMENT & TECHNOLOGY SUPPORT SYSTEM


1. Analysis of all type of equipment failures & forced outages including trips,

BTL etc especially of repetitive nature and propose engineering solutions

for its prevention.

2. To provide adequate engineering support to all such plant betterment

plans.

3. Technical Audit of the units/power generation plant. Set standards of test

procedures for testing of coal, water, equipment and system performance

etc

4. Undertake plant betterment proposals wrt environmental & ecological

needs, statutory needs as also the optimum generation & reliability

requirements with due cost benefit evaluations.

5. Creation of adequate awareness at different level about all such needs,

organize budget & finance and ensure implementation of these plans in a

cost efficient manner.

6. To create expert & specialist groups in the areas of Mechanical- Boiler,

Turbine, Balance of Plant etc, Electrical- Generator, Transformer, Switch

yard etc, Control & instrumentation, Operation- Water chemistry, Energy

Efficiency etc.


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ENTERPRISE RESOURCE PLANNING (ERP) & INFORMATION

TECHNOLOGY (IT)


1. Advance planning of O&M requirements of the station, resource gap

analysis & management wrt manpower, skill, training needs, centralized

spare pools & inventory management, organization structure &

restructuring from time to time to face the new business challenges before

the organization.

2. Define & revisit the role & responsibilities of the organization structure to

meet the present as well as the future anticipated needs based on

business expansion plans.

3. Training & redeployment of O&M personnel for proper & effective

utilization.

4. Computerization & net working of all O&M Systems with ERP and usage

of Information Technology to ensure quick management information

system (MIS)

5. Use of MIS for management decision support system (M-DSS) to reduce

dependence on human judgment, better planning & coordination and

optimum resource utilization

6. Commercial Management of the organization through efficient cost control

& financial discipline.


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NTPC


HEAD QUARTER GROUP


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ROLE OF NTPC: PIE-HQ GROUP

1. To assist the station in formulating guidelines for operation & maintenance

2. To carry out selective analysis of unit outages and other operational

related problems.

3. To compile data & feed back from each station related to the following:

Major operational events

Major equipment outage & their analysis

Plant Betterment Plans & Modification of schemes

Equipment/unit performance & corrective plans, if any.

Uniform code of practices wrt O&M of units & equipments

4. To organize workshops and awareness programme on various tropics

connected to operation & maintenance.

5. Review & evaluate the performance of protection & interlocks and other

auto loops and suggest improvements, if any.

6. To assist SRM-NTPC, PIE group & station heads to conduct monthly

operation review team meetings.

7. To review & monitor the efficiency parameters of each unit of the stations.


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OPERATION PARAMETER PERFORMANCE

MANAGEMENT SYSTEM

FOR

NTPC - PIE STATIONS


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1.0 INTRODUCTION:

Operation Management System has been developed to standardize all systems

related to Operation Performance and to achieve uniform implementation of

practices through-out all PIE stations. Sincere efforts and implementation of the

systems shall pay rich dividends in the form of high generation, plant load factor,

availability as well as high loading factor on sustained basis.

Over the last decade, the Government of India (GOI) has introduced several

changes under Power Sector Reforms. The beginning of the process of

liberalization & decontrol, advent of availability base tariff (ABT) system, free

governor mode operation (FGMO) regime and the Indian Electricity Act 2003 has

opened new and challenging opportunities. The business scenario of power

sector has begun to change with the introduction of availability based tariff (ABT)

and new initiatives in the grid management. The changed scenario also shifts

focus to merit order generation by power utilities.

Operation Management System manual has a focus on efficient, economic and

reliable power generation.

The following aspects are covered in the Operations System Management

manual.

1. Objective of operation management

2. Reporting, logging & monitoring system at station

3. Reporting & monitoring system at PIE head quarter

4. Operation performance & efficiency - review system

5. Operation review team (ORT) system


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6. Technical audit system

7. Role of operations staff

8. Role of operation efficiency staff in monitoring of plant performance.

9. Role of chemist & desirable water chemistry parameters

10. House keeping at station

11. Guidelines for allowing by pass of P&I, auto loops etc and their

restoration

12. Guidelines for availability of technical documents e.g. OMIM, P&I

diagrams and latest technical documents.

13. Guidelines for enhancement of technical skill through periodic

training, orientation and awareness programme.

14. Guidelines for preservation & disposal of charts, log sheets,

DAS printout, Log book.


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2.0 OBJECTIVES OF OPERATION MANAGEMENT

The Objectives of Operation Management are described as under:

1. To ensure safe and accident free operation wrt surrounding environment

and in compliance with the statutory provisions

2. To operate the stations at maximum capability

3. To ensure minimum partial loading of units

4. To ensure the compliance of all operational systems, as envisaged

5. To operate the plant and accessories at optimum efficiencies within

defined operational regime

6. To ensure efficient and reliable operation of units with sustained

performance.

7. To operate the plant at minimum oil consumption, auxiliary consumption

and make up water consumption

8. To ensure optimum water chemistry parameters

9. To operate the units at maximum availability

10. To ensure continuous development & up-gradation of operational skill of

the operating personnel


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3.0 DEFINITIONS:

ITEM DEFINITION

Installed Capacity The maximum capability of the generating unit/ station to

deliver ex-bus MWh or maximum continuous rating

De-rated Capacity The duly certified and approved by competent authority (CEA)

the maximum capability of the generating unit/ station to

deliver ex-bus MWh or maximum continuous rating,

Availability Factor on

bar

Availability Factor on bar of a unit is the percentage ratio of

operating hours and the total hours for a given period of time.

Reserve Shut down Duration of shutdown of unit because of no power demand

situation and unit with drawl imposed by the grid.

Auxiliary Power

Consumption (APC)

The ratio as a percentage of energy generated (in KWh) at

generator terminals minus energy delivered (in KWh) at the

generating station switchyard to gross energy in KWh

generated at the Generator terminals.

Actual Generation ex

bus (AG)

Actual generation of station available for dispatch or actual

sent out energy (Ex-bus) .

Black Start Procedure The procedure necessary to recover the unit from a total

blackout condition i.e. total power failure in the grid.


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CEA Central Electricity Authority.

CERC Central Electricity Regulatory Commission.

Declared Capacity(DC)

The capability of the generating unit/ station to deliver ex-busMWh declared by the generating station.

Demand The demand of active power MW and reactive power MVAR

of electricity unless otherwise stated.

Dispatch Schedule Net MW (ex-bus) and MWH output of a generating station,

schedule to be exported to the grid from time to time.

Drawl Schedule Net MW (ex-bus) that a state is scheduled to receive from the

Inter State Generating Station (ISGS) including bilateral

exchanges from time to time.

Downtime Time duration for which an equipment or unit is out of service,

as a result of equipment/unit failure.

Disaster Management

Plan

Action plan to provide the maximum practicable protection for

equipments, personnel and the environment in the event of a

major man made disaster or natural crisis e.g. earthquakes,

floods, fire, etc.

Dry Flue gas loss The heat loss from the boiler in the dry component of gases to

the stack.

Expert System A software based system, which makes or evaluates

decisions based on rules established within the software.

Emergency

Instructions

Standing instructions to be carried out by operation engineer/

operator during emergencies like grid failure, hydrogen

leakage, fire etc.

Free Governor Modeof Operation (FGMO)

Operation of unit with turbine governor modulation in actionwith respect to grid frequency.


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Gross Generation Total electrical output from the generator terminal.

Governor Droop The percentage drop in system frequency which would cause

the generating unit under free governor action to change itsoutput from zero to full load.

Gross Calorific Value

(GCV)

The heat produced in kcal by complete combustion of one kg

of solid fuel or liquid fuel or one standard meter of gaseous

fuel, as the case may be.

Gross Heat Rate

(GHR)

The heat energy in kcal input required to generate one KWh

of electrical energy at generator terminal

Heat Balance

Diagram

A diagram expressing temperature, pressure, enthalpy and

flow values throughout the cycle for a given set of conditions.

Loading Factor (LF) It is the percentage ratio of plant load factor and availability

factor on bar.

Maximum Continuous

Rating (MCR)

The maximum continuous output at the rated generator

terminals, guaranteed by the manufacturers at rated

parameters.

Make up water

consumption

It is the percentage ratio of DM water consumption and MCR

capacity of boiler.

Multiple Unit Tripping Outage of more than one unit simultaneously due to any fault

Net Generation Total electric output at switchyard. It is the difference betweenelectrical generator output and the auxiliary output.

Net Heat Rate(NHR) The heat energy in Kcal,input to a generating unit to deliverone KWh at the switchyard.

Operation &

Maintenance Cost(O&M Cost)

In relation to a period means the expenditure incurred in

operation & maintenance of the generating station includingmanpower, spares, consumables, insurance & overheads.

Operation Co-ordination Committee(OCC)

A committee of REB with members from all the constituentswhich decides the operational aspects of the Regional Grid


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Operating Hours The length of time that an item of equipment is actuallyoperating.

Outage recurrence Outage of same unit over the period for same nature of fault.

Overall PlantEfficiency

It is the ratio of electrical energy sent out to the heat suppliedto steam in boiler.

Plant Load Factor(PLF)-actual

In relation to a given period, is expressed as the percentageof total actual KWh generated at generator terminals toinstalled capacity, expressed in KW multiplied by number ofhours in that period.

Plant Load Factor(PLF)-deemed

In relation to a given period, is expressed as the percentageof total deemed (actual plus restriction imposed by the grid)KWh generated at generator terminals to installed capacity,expressed in KW multiplied by number of hours in that period.

Partial Loading It is the percentage by which unit runs at reduced load.

Protective Device Devices and assets intended to eliminate or reduce theconsequences of equipment failure.

Permit To Work(PTW)

The prime document used by the maintenance unction tomanage maintenance tasks.

PerformanceParameters

Those variables in a power cycle which can be measured orcalculated and which are indicative of the level of performanceof a component, system, equipment or unit.

Regional Electricity

Board (REB)

A board constituted by resolution of Central Government for a

specified region for facilitating the integrated operation of thpower system in that region.

Regional LoadDispatch Centre(RLDC)

The center so designed for a specified region where theoperation of the power system in that region and theintegration of the power system with other regions and areasare coordinated.

Re-commissioningChecklist

List of checks, which are adhered for every equipment duringthe trial run and re-commission for safe and trouble freeoperation of the equipment.

Sent Out Capability(SOC)

Sent out capability of a generating station means thecapability to deliver ex-bus MHh based on which availability

shall be worked out.Schedule Generation(SG)

Ex bus scheduling in MW as given by RLDC to the generatingstation.

Specific OilConsumption

It is the consumption of oil (ml) per KWh generation.

Specific CoalConsumption

It is the consumption of coal (Kg) per KWh generation.


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Technical Co-ordination Committee(TCC)

The committee set up by REB to coordinate the technical andcommercial aspects of the operation of the Regional grid.

Throttle Governing All first stage nozzles are in common annulus and aresubjected to the same amount of throttling.

UnscheduledInterchange (UI)

Variation in actual generation and the schedule generation

Unit Tripping Outage of a unit due to actuation of any protection or theoutage of unit during emergency condition.

Un burnt carbon loss This loss is due to amount of carbon, which remains as aresidue in the ash from boiler.

Variable PressureOperation

An operating method in which the load is changed by varyingthrottle pressure in lieu of changing valve position .

Valves Wide Open The turbine control valve setting which corresponds to allturbine control valves fully open.

Wet Flue gas loss This is the heat loss from the boiler in the flue gas due towater vaqpour present as moisture & hydrogen in coal.


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4.0 CALCULATION OF OPERATIONAL PARAMETERS

1.0 PLANT LOAD FACTOR (PLF):

a) Plant Load Factor for the Unit (%):

Gross Generation (MU) of a Unit (Reference period)PLF (Unit) = ------------------------------------------------------------------------------ x 100

Rated Gen. Capacity (MW/1000) of Unit x No. of Hrs (Ref. Period)

b) Plant Load Factor for the Stage I (%):

Sum of Gross Generation (MU) of Stage-I units (Ref. period)PLF (Stg-I) = ------------------------------------------------------------------------------ x 100

Rated Gen. Capacity (MW/1000) of Stg-I x No. of Hrs (Ref. Period)

c) Plant Load Factor for the Stage-II (%):

Sum of Gross Generation (MU) of Stage-II units (Ref. period)PLF (Stg-II) = ----------------------------------------------------------------------------- x 100

Rated Gen. Capacity (MW/1000) of Stg-IIx No. of Hrs (Ref. Period)

d) Plant Load Factor for the Station (%):

Sum of Gross Generation (MU) of all Units over a reference periodPLF (Station) =----------------------------------------------------------------------------- x 100

Rated Gen. Capacity (MW/1000) of all Units x No. of Hrs (Ref. period)

2.0 AVAILABILITY FACTOR ON BAR:

a) Availability Factor on bar for the Unit (%)

Operating Hours of the unit over the reference periodA.V.F (On bar) = -------------------------------------------------------------------- x 100

Total hours (Reference period)


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b) Availability Factor on bar for Stage-I Units, (AVFs1) (%)

Sum of the Availability Factor of Stage-I UnitsA.V.F (On bar) = -------------------------------------------------------------

Number of units of the Stage-I (N1)

c) Availability Factor on bar for Stage-II Units, (AVFs2) (%)

Sum of the Availability Factor of Stage-II UnitsA.V.F (On bar) = -------------------------------------------------------------

Number of units of the Stage-II (N2)

d) Availability Factor on bar for Station, (AVFs) (%)

AVFs1 x N1 x C1 + AVFs2 x N2 x C2A.V.F (On bar) = ------------------------------------------------

N1 x C1 + N2 x C2

Where,

AVFs1, AVFs2 =Availability Factor On bar,(%) of Stage- I & Stage-II respectively

N1, N2 = Number of Units of Stage - I & Stage-II respectively

C1, C2 = Capacity (MW) of units of Stage -I & Stage-II respectively

3.0 MACHINE AVAILABILITY:

a) Machine Availability Factor for the Unit (%)

Sum of Operating Hours & outage hours due to fuel andgrid restriction of unit (Reference period)

A.V.F (M/C) = ---------------------------------------------------------------------------- x 100Total hours (Reference period)


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b) Machine Availability Factor for Stage-I Units (%)

This can be calculated sane way as shown in 2b)

c) Machine Availability Factor for Stage-II Units (%)

This can be calculated sane way as shown in 2c)

d) Machine Availability Factor for Station (%)

This can be calculated sane way as shown in 2d)

4.0 AVAILABILITY BASED ON DC:

In relation to a thermal generating station Availability for any period means the

average of the daily average declared capacities (DCs) for all the days during that

period expressed as a percentage of installed capacity of the generating station

minus normative auxiliary consumption. Availability shall be computed in

accordance with the following formula:

NAvailability = 10000 DCi /{ N x IC x (100-AUXn)} %

i=1

Where,

I.C = Installed Capacity of the station in MW

DCi = Average declared capacity for the ithday of the period in MW.

N = Number of days during the period

AUXn = Normative Auxiliary power consumption as a percentage of gross

generation


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5.0 LOADING FACTOR,(%):

Loading Factor (%) of Unit or Stage-I/II or Station:

Plant load Factor of Unit or Stage-I/II or Station (%)Loading Factor = -------------------------------------------------------------------- x 100

Availability Factor on bar of Unit or Stage-I/II or Station (%)

6.0 PARTIAL LOADING:

Partial Loading of Unit or Stage-I/II or Station:

Partial Loading (%) = (100 - Loading Factor in %)

7.0 EQUIPMENT PARTIAL LOADING (%)

Equipment Partial Loading (%) of Unit, Stage-I/II or Station:

Loss of Generation of Unit, Stage-I/II or Station in MU (Ref. period)=----------------------------------------------------------------------------------------- x 100Total rated Generation (MU) of Unit, Stage or Station

(Ref. Period excluding outage Hours)

8.0 GROSS HEAT RATE:

Gross Heat rate (Kcal/KWh) of the Unit, Stage-I/II, and Station is expressed asfollows:

Average GCV for the ref. Period (Kcal/Kg) x Total Coal Cons. (Kg) (Ref.period)= -----------------------------------------------------------------------------------------------------

Total Generation (KWh) (Ref. period)

Gross Heat rate (Kcal/KWh) of the Unit can also be expressed as follows:

Gross Turbine Heat Rate (Kcal/Kwh)= ------------------------------------------------ x 100

Boiler Efficiency (%)


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Where,Heat input to Turbine (Kcal)

Gross Turbine Heat Rate = -----------------------------------------

Generation at Generator terminal

Heat input to Turbine = [ Main Steam flow (Kg) x (Enthalpy at HP Turbine inlet Enthalpy of FW at ECO inlet) + CRH Steam flow (Kg) x (Enthalpy at IP Turbine inlet- Enthalpy at HP Turbine exhaust) + Super heater spray flow (Kg) x (Enthalpy atHP Turbine inlet Enthalpy of S/H spray) + Reheat spray flow (Kg) x (Enthalpy at IPTurbine inlet Enthalpy of R/H spray)]

Where, unit of enthalpy of steam and water is Kcal/Kg

Net Heat rate (Kcal/KWh) of the Unit, Stage-I/II, and Station is expressed as follows

Gross Heat Rate (Kcal/KWh)=----------------------------------------- x 100

(100- APC in %)

The monthly / yearly average Gross Heat Rate shall be calculated by weightedaverage as per the following formula

GHRix KWh

i= ----------------------- KWhi

Where,GHRi = Gross Heat Rate (Kcal/KWh) of the i

th dayKWhi = Generation (KWh) of the i

th day

9.0 SPECIFIC OIL CONSUMPTION (ml/KWh):

Specific Oil Consumption (ml/KWh) of Unit, Stage-I/II, and Station is expressed asfollows:

Oil Consumption (KL) (Ref. period)= ---------------------------------------------------------------------------------------------------

Total gross generation (MU) of the Unit, Stage-I/II, Station (Ref. period)


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10.0 SPECIFIC COAL CONSUMPTION (Kg/KWh):

Specific Coal Consumption (Kg/KWh) of Unit, Stage-I/II, and Station is expressed asfollows:

Coal Consumption (MT) (Ref. period)= ---------------------------------------------------------------------------------------------------

Total gross gen. (MU) of the Unit, Stage-I/II, Station (Ref. period) x1000

11.0 AUXILIARY POWER CONSUMPTION (%):

Aux. Power Consumption (%) of Unit, Stage-I/II, and Station is expressed as follows: