Turb.sect2.Gen Spec 19Sept07

Medupi Power Station Employer’s Requirements Package No. 3 STG Contract No: 4600008582

Eskom

Employer’s Requirements

Turbine Generator with auxiliary plant

Section 2 – General Specifications and Requirements 2.1 Scope of the Contract.................................................................................... 3 2.2 Items not mentioned...................................................................................... 3 2.3 Design Criteria............................................................................................... 3

2.3.1 General Design ............................................................................................ 3 2.3.2 Additional Design Criteria to Meet the SA Grid Code ................................... 4 2.3.3 Reliability and Availability ............................................................................. 4 2.3.4 Interchangeability of parts ............................................................................ 5

2.4 Guarantee and Technical Schedules of the Plant ......................................... 5 2.5 Not Used ....................................................................................................... 6 2.6 Metrication..................................................................................................... 6 2.7 Drawings and data ........................................................................................ 6 2.8 Quality Assurance Requirements .................................................................. 6 2.9 Sub-Contractors ............................................................................................ 7 2.10 Contract Spares ............................................................................................ 7 2.11 Testing of fully assembled prototype or reference turbine generator sets ..... 8 2.12 Operating and Maintenance Staff to Witness Erection .................................. 9 2.13 Process to and after Completion ................................................................... 9 2.13.1 Capability Tests............................................................................................. 9 2.13.2 Seventy Two Hour Run ............................................................................... 10 2.13.3 Thirty Day Reliability Run ............................................................................ 10 2.13.4 Six Month Proving period ............................................................................ 12 2.13.5 Twelve Month Maintenance Period ............................................................. 12 2.13.6 Continued Availability of Skilled Engineer ................................................... 13 2.14 Testing of Turbine generator Plant .............................................................. 13 2.15 Foundations, supporting structures and miscellaneous fabricated items..... 14

2.15.1 Concrete Foundations and Plinths ............................................................. 14 2.15.2 Supporting structures ................................................................................. 14 2.15.3 Steel work, steel flooring, platforms, stairways, ladders, handrails

and related items........................................................................................ 15 2.15.4 Component lay-down areas........................................................................ 16

2.16 Tools, special tools and equipment, lifting and handling tackle ................... 16 2.17 Balancing Facilities...................................................................................... 17 2.18 Off loading and handling of the generator stator ......................................... 18 2.19 Operating and maintenance instruction manuals ........................................ 18 2.20 Turbine generator Plant 3D Layout Models ................................................. 19 2.21 Plant codification & Labelling....................................................................... 20 2.22 Flanges and joint rings ................................................................................ 20 2.23 Bolts, studs, nuts, washers and threads...................................................... 20 2.24 Lubrication................................................................................................... 21 2.25 Grease nipples and grease guns................................................................. 21 2.26 Thermal Insulation....................................................................................... 21 2.27 Rubber lining ............................................................................................... 22 2.28 Valves and other name plates and labels.................................................... 23 2.29 Fire Protection ............................................................................................. 23

Turb.Sect2.Gen Spec 19Sept07.doc Page 1 of 32


2.29.1 Scope ......................................................................................................... 23 2.29.2 Interfaces.................................................................................................... 24 2.29.3 General Requirements ............................................................................... 24 2.29.4 Applicable Codes and Standards ............................................................... 26

2.30 Environment ................................................................................................ 26 2.31 Vibration, Shock and Noise ......................................................................... 26

2.31.1 Vibration and Shock (See Section 12)........................................................ 26 2.31.2 Limiting Value for Noise Generation........................................................... 27

2.32 Welding ....................................................................................................... 28 2.33 Corrosion Protection and Painting............................................................... 28 2.34 Chemical Dosing and Monitoring (Sampling) .............................................. 28

2.34.1 Chemical Dosing ........................................................................................ 28 2.34.2 Lay-up/Preservation/Storage...................................................................... 29 2.34.3 Chemical Monitoring (On-line Analyses and Sampling) ............................. 29

2.35 Alternative Offers for Identified items. ......................................................... 32



2.1 Scope of the Contract

See section 1.3

2.2 Items not mentioned

See section 1.3.1

2.3 Design Criteria

2.3.1 General Design

The Works shall be based on existing proven equipment which has operated for a sufficient length of time to have demonstrated performance and availability.

The design on which the offer shall be based is indicated in Section 1.

The Employer’s particular requirements in respect of Codes and Standards for this contract are defined in attached Schedule B.1-1, which also includes the applicable Eskom standard specifications. These standard specifications shall be read in conjunction with the national and international Codes and Standards and codes specified in this schedule as well as with those proposed by the Contractor and approved by the Engineer and/or the Chief Inspector of Machinery for the Plant and Material in question.

The Contractor shall ensure that, with exceptions defined in this Employer’s Requirements, the Codes and Standards and codes of practice are all of the same national standard, e.g. all EN, or all USA, etc., as the case may be. The mixing of standards and codes of different nationalities shall be avoided. Any deviation from this requirement shall be subject to the approval of the Engineer. The mixing of international Codes and Standards (e.g. ISO, etc.) with those of a particular nationality is permissible provided that this has been approved by the Engineer and that there is complete compatibility between the Codes and Standards so offered.

The Contractor shall complete Schedule B.3 clearly defining any proposed alternatives to those Codes and Standards specified by the Employer provided the alternatives have been approved by the Engineer. The Contractor’s reasons for the substitutions shall be detailed fully.

Special requirements for the application of Codes and Standards to the high pressure feed train of the turbine generator Works are defined in Sections 8 and 10. The Works shall also comply fully with the requirements of South African law including the OHS Act No.85 of 1993 as amended. (Refer to Clause 13.7 of the Particular Conditions - Adjustments for Changes in Legislation.)



Coded vessels such as deaerators, storage tanks, feed heaters and associated drain control vessels and similar items shall be designed to one particular code as required in terms of the South African OHS Act No.85 of 1993 as amended.

Items of Plant and castings to be lifted by crane or other lifting devices shall be provided with integral lifting eyes, lugs, trunnions, or some other means approved by the Engineer. Eyebolts shall only be provided for minor items of Plant.

The bearings of all major Plant shall be arranged for easy in situ replacement.

Motor bearings shall comply with the requirements of the Employer’s specification as defined in Schedule B.1-1.

The Works will be designed to facilitate easy accessibility for inspection, cleaning, maintenance, and repairs and will be designed to ensure satisfactory operation under the atmospheric and other conditions prevailing at the site.

2.3.2 Additional Design Criteria to Meet the SA Grid Code

All design criteria, including all the criteria for licensing, that is applicable to the Contractors scope of work as mentioned in the South African Grid Code must be complied with.

All deliverables that are required for licensing purposes that are applicable to the Contractors scope of work as mentioned in The South African Grid Code must be produced by the Contractor.

The turbine generator plant shall comply with The South African Grid Code. The boiler plant may or may not comply with The South African Grid Code and thus the Contractor shall perform a study to investigate options for improving the under-frequency response of the boiler and turbine unit.

The investigation shall entail a detailed dynamic simulation study of the boiler and turbine including all items of plant necessary to represent the dynamic response of the turbine and boiler unit.

These options shall be described in a report issued to the Engineer.

Attention is, in particular, drawn to the South African Grid Code requirement that “The Unit shall be designed to be capable of a minimum response of 3% of MCR sent out within 10 seconds of a frequency drop over the range from minimum load to 97% of MCR sent out. The response shall be sustained for 10 minutes.”

2.3.3 Reliability and Availability

In the overall design of the Plant preference shall be given to achieving and readily maintaining maximum reliability and availability.

Each item of Plant shall be suitable for the condition which it shall be expected to meet. In particular the material and design of each item shall be such that no



excessive distortion, growth or deterioration of the item shall occur, nor shall it be subjected to stress or strain beyond its design values during normal operation.

Sufficient component reliability shall be designed into the Plant to enable overall Plant availability targets to be achieved throughout its design life. Reliability and redundancy calculations shall be performed using established methodologies to demonstrate the adequacy of the designs to achieve Plant performance targets where specific requirements are not stated in this document. Such analyses shall be an integral part of the design process in which cross-functional design decisions, cost-benefit trade-off studies and overall optimisation of the Plant are considered. The Contractor will provide to the Engineer, details of the methodology and results.

The design of structures, systems and components shared by two or more Sections shall incorporate features, such as redundancy and mutual support, to prevent the occurrence of multiple unit trips or outages resulting from any Plant failure or from any maintenance activity of the shared structures, systems and components.

2.3.4 Interchangeability of parts

All similar wearing parts shall be interchangeable with each other and with the corresponding spares, so that replacement of a worn part can be carried out with a minimum of adjustment.

The Contractor shall ensure complete interchangeability between turbine generator sets of rotating parts and particularly of turbine and generator rotors. The LP turbine rotors of the double LP Turbine design shall be inter-changeable. To this end rotating parts shall have identical journal, coupling, and coupling-bolt dimensions, and the holes for coupling bolts shall be accurately located by means of jigs or other approved methods (See also Section 3.6). Stationary parts shall be machined to close tolerances where mating with interchangeable parts is required.

The Contractor shall record precisely the dimensions of all wearing and rotating parts, and the identity and particulars of jigs and fixtures which will be used in the manufacture of the machine, so that future orders for corresponding parts of similar machines will ensure complete interchangeability with similar parts of the units supplied under this contract.

2.4 Guarantee and Technical Schedules of the Plant

Refer Schedule C - Guarantees.

Refer Schedule D - Technical data.



2.5 Not Used

2.6 Metrication

The International Organisation for Standardisation (ISO) system of weights and measures is to be used in all documents, correspondence and drawings.

Bolts, nuts and studs, unless for a special purpose, shall be to Metric standards.

The Contractor shall supply metric sized Plant and Material, unless otherwise approved by the Engineer.

Where available, the metric equivalents of specifications, standards and codes of practice shall apply.

2.7 Drawings and data

The Contractor shall provide the drawings and data specified in Schedule A.3-1 and A.3-2 together with any other drawings and data which the Employer considers are necessary to provide a record of the complete design and construction details (this does not include manufacturing drawings) of the Works. (See also Section 17)

The drawings and data shall be provided in both hard copy and electronic format. The applications used to compile and manage the electronic format of drawings and data shall be approved by the Engineer before drawings and data are compiled. (See also Section 17)

Copies of any drawings that may be required for maintenance, modification or repair of failed equipment as stated in Schedule A.4-1 shall be kept in the Contractor's offices and the Employer shall have access to these drawings on request.

2.8 Quality Assurance Requirements

The Employer places emphasis on the provision of a comprehensive Quality Management System for all phases of the project.

The Contractor’s Quality Management System shall conform to the Employer’s requirements.

The quality requirements are as per ISO 9001, and the Project quality standard ‘1253_PRO_010 Contractor Quality Requirements - Turbine.doc’.

The documents to be submitted for review and acceptance by the Engineer after the Contract Date and prior to the commencement of work are referred to in the above referenced quality document.



2.9 Sub-Contractors

Refer ATC-16, List of Sub-Contractors.

2.10 Contract Spares

As required in terms of this Employer’s Requirements all spares shall be identical and interchangeable with the respective components of the Works. Materials from which spares are manufactured, manufacturing standards and quality assurance procedures, shall be identical to those adopted for the respective components of the Works. The monitoring and inspection procedures established for the main Plant items shall also apply to the spares to be provided under this contract. All spares ordered shall be checked for interchangeability.

The Employer reserves the right to order all or any of the spares offered for the Works.

The Contractor shall obtain priced recommended spares lists from sub-contractors before sub-contract order placement. The Employer shall specify quantities of spares required within 3 months of receiving these priced spares lists for delivery prior to commissioning of the first Section.

After the contract date, the Contractor shall submit comprehensive details of all the spares, for which prices will be submitted. This information shall include all the manufacturers and suppliers type and identifying references together with drawing reference numbers and an itemised breakdown of the prices quoted. These details shall cover all spares quoted for, whether or not ordered by the Employer.

The cost of spares shall include any charges for implementing the Employer’s requirements for the Codifications System specified in section 2.21.

The Contract includes the supply of the spares identified and priced in Schedule H4 and Schedule H6 and all spares shall be packed separate from the rest of the equipment and shall be clearly and indelibly marked CONTRACT SPARES. The order number and the name of the power station shall also appear on the container labels and the packing lists.

The Contractor shall obtain verification from the Engineer that all spares in each consignment have been received.

All the spares including the spare running blades and stationary blades of turbine and spare turbine rotors shall be delivered to the Project Site. Specific storage specifications and maintenance requirements for the spares shall be provided with the spares delivered.

The Contractor shall undertake that any spares ordered for units supplied under this contract shall incorporate all modifications found necessary during the contract period. He shall also undertake that any such spares already on Site will be replaced by modified spares without cost to the Employer.



Special Requirements for Spares:

(i) Spares shall be supplied over or under-sized as the case may be. Over and under-sized spares shall be clearly identified in the subsequent detailed Schedule to be provided by the Contractor and all packing lists.

(ii) Governor valve spindles, sleeves and seats and similar spares shall be delivered, in matched, assembled units.

(iii) Sufficient spare jointing material shall be provided by the Contractor.

(iv) In the Schedules, "Set" shall mean that a sufficient number of components shall be included so that each part of the designated main item may be replaced. The Schedules shall include complementary lists of all components making up each "set". The lists shall include marks and type references, where applicable, and shall be cross-referenced to the schedules and item numbers.

(v) The item numbering system for spares appearing in Schedules H.4 and H.6 shall be quoted and strictly adhered to in all quotations and correspondence.

The Contractor shall base his recommendations for spare piping on all classes of piping (alloy and carbon steels), included in the Contract Works, which are not manufactured in the Republic of South Africa. In the case of-straight piping the Contractor shall submit prices per metre run of each grade and size, and in the case of bends, form pieces and transition pieces, he shall submit a separate price for each item offered.

The Employer reserves the right to order all or any of the spare piping offered.

Spare piping shall be adequately protected internally and externally for long term outdoor storage. Spare piping ordered shall be handed over to the employer before the first set is taken over.

2.11 Testing of fully assembled prototype or reference turbine generator

The Contractor provides the following:

i) Design comparison of the offered turbine-generator with the fully tested prototype or a recently commissioned reference set on which the offer is based. References may be given per module of the turbine-generator train. For the generator, either an operation record or a type test will be provided. For the Last Stage Blades (LSB) references or information from pit tests will be provided.

ii) Copies of the test or commissioning log sheets of the prototype or reference set.

iii) Full details of service or experience list with the proposed last stage LP blading at high back pressures and/or results of turbine model tests on blading subject to high back pressures



2.12 Operating and Maintenance Staff to Witness Erection

Every opportunity shall be afforded to the Employer’s Personnel to obtain first hand knowledge of the turbine enerator during erection. To this end the Contractor shall liaise with the staff to ensure that members are present during all important and major erection operations and adjustments.

2.13 Process up to and after Take Over

The following diagram reflects the process from first steam to set to the end of the Defect Notification Period :

2.13.1 Capability Tests

During commissioning of a Section, the Contractor shall be permitted, as far as is convenient to the Employer, to make any preliminary trial that he may desire, and upon the finalisation of such preliminary trial to his satisfaction, the Contractor shall give the Engineer written notice that the Section is ready to be subjected to the capability tests (cap tests) and to those tests specified in Sections 12 and 13. Such notice shall suit the requirements of the Employer and is stipulated in the Particular Conditions, sub clause 9.1 - Tests on Completion, Contractors Obligations.

No alterations or adjustments shall be made to the Section during the capability tests without the Engineer's written permission.

Unless otherwise agreed by the Employer and the Contractor, the tests shall be carried out by the Contractor in the presence of the Employer. The Party carrying out the tests shall provide, install and use such of his instruments and



temporary equipment as may be necessary for the purpose of the tests.

Should the Section fail such tests, any further tests shall be carried out upon the terms and conditions laid down in the Employer’s Requirements or, if no such terms and conditions are laid down in the Employer’s Requirements, upon such terms and conditions as may be agreed upon between the Employer and the Contractor.

2.13.2 Seventy Two Hour Run

After satisfactory completion of erection, commissioning and capability testing of the Section, the Section shall be operated continuously at full load (TMCR) for a 72 hour period.

For the avoidance of doubt and for the purpose of Sub Clause 10.3 Particular Conditions [Interference with Tests on Completion], carrying out the Tests on Completion includes interruptions to the 72 Hour Run. To this end the entitlement, subject to Sub Clause 20.1 Particular Conditions [Contractor's Claims], which allows the Contractor to claim an extension of time and Cost plus reasonable profit as stated in Sub Clause 10.3 Particular Conditions [Interference with Tests on Completion] will apply where:

• the 72 Hour Run is commenced but interrupted, by a cause for which the Contractor is not responsible and the Contractor suffers (or will suffer) delay and/or incurs (or will incur) Cost as a result of the interruption to the 72 Hour Run (provided that the Contractor shall not be entitled to claim for Cost unless such interruption endures for a period of more than 48 hours, whether consecutively or cumulatively);

• Notwithstanding Sub Clause 10.3 Particular Conditions [Interference with Tests on Completion], if the 72 Hour Run is interrupted for more than 14 days cumulatively by a cause for which the Contractor is not responsible, the 72 Hour Run (but not, for the avoidance of doubt, the Tests on Completion as a whole) shall be deemed to have been completed on the date when the 72 Hour Run would otherwise have been completed.

2.13.3 Thirty Day Reliability Run

After having satisfactorily completed preliminary and functional tests on the various plant component systems, after capability testing, and after the Section has operated at full load (TMCR) for a 72 hours run period or close as possible (to Employer satisfaction), the Contractor will inform the Employer that he is ready to start the Initial Operation (Reliability Run) of the Section (scope under Contractor’s responsibility).

The Initial Operation will consist of three periods of ten (10) days each, hereinafter called Run Periods

The completion of the three Run Periods constitutes the completion of the Initial Operation (Reliability Run).



An interruption is any event attributable to the Contractor resulting in output reduction below that demanded by the Grid

Within the Initial Operation, one interruption with maximum interruption of 8 hours will be allowed. In case of further interruption, only the Run Period in which it occurs will be started again.

During the Run Period, the Section shall be operated continuously with main fuel and support fuel if necessary in accordance with the requirements of the Grid (power or frequency control mode, load variations as per dispatch demand) and with no tests on components and systems being willingly performed (in particular no start-up test, island operation test, fuel transfer test, equipment redundancy test or electrical source transfer test shall be performed).

During the Run Periods : the load demand from the Grid will remain significantly above the technical minimum of the Turbine Island and the load variation requirements, frequency, power factor, etc… will remain within the limits given by the Contractor.

If the load demand falls below the operating condition limits of the turbine-generator or if the load variation, frequency and power factor are beyond these conditions, the unit will be isolated from the Grid. For each cold start, 5,5 additional hours of "reliable operation" will be credited to the run and 3 Additional hours for each hot re-start.

The Initial Operation will be carried out under the responsibility and supervision of the Contractor, together with the participation of operation personnel of the Power Plant operator errors will not be considered as a lack of reliability.

Non respect of noise level, emissions, quality of discharge water shall not be considered as reliability criteria.

During the Initial Operation the Contractor shall be allowed to make minor routine maintenance and process adjustments as may be necessary without interruption. Unavailability of auxiliary items or non mandatory equipment shall not be considered, as long as no interruption ensues.

Contractor will have access to Employer’s spare parts available on site, provided that in the event that any such spare parts are used during this period, Contractor shall immediately re-order or replace such spare parts.

The running of the Initial Operation shall be suspended during events such as shutdown owing to causes beyond the Contractor’s responsibility or any period when the Employer fails to provide conditions for Turbine Island normal operation, or event of Force Majeure.

The Employer shall have the option at any time during this period of Initial Operation to declare that the Section has successfully demonstrated its reliability and that the Initial Operation (Reliability Run) has been completed

After successful completion of the 30 day Reliability Run, the Section will be taken over by the Employer according to the terms and conditions stated in Clause 10 of the Particular Conditions.



For the avoidance of doubt and for the purpose of Sub Clause 10.3 Particular Conditions [Interference with Tests on Completion], carrying out the Tests on Completion includes interruptions to the 30 Day Run. To this end the entitlement, subject to Sub Clause 20.1 Particular Conditions [Contractor's Claims], which allows the Contractor to claim an extension of time and Cost plus reasonable profit as stated in Sub Clause 10.3 Particular Conditions [Interference with Tests on Completion] will apply where:

• the 30 Day Run is commenced but interrupted, by a cause for which the Contractor is not responsible and the Contractor suffers (or will suffer) delay and/or incurs (or will incur) Cost as a result of the interruption to the 30 Day Run (provided that the Contractor shall not be entitled to claim for Cost unless such interruption endures for a period of more than 7 days, whether consecutively or cumulatively)

2.13.4 Eighteen Month Defect Notification Period

The Section shall then continue in commercial service as directed by the Employer for the Defects Notification Period.

The Defects Notification Period shall endure for 18 months, commencing after Take over, during which period the Section shall be operated at a load as close to MCR as feasible dependant upon the Employer’s operational requirements, during which period the Section shall display the reliability, controllability and performance required under the Contract.

Should there be a forced outage for which the Contractor is responsible or an outage requested by him, the Employer reserves the right to extend the Defects Notification Period commensurate with the outage period.

The Contractor documents evidence of this run and all other running time in a daily log during the Defects Notification Period. This log is to include main plant parameters and any abnormalities that occurred. This log shall be available to the Employer. The Party responsible for any interruption in the running of the plant is to be identified and agreed with the Employer within 24 hours of the occurrence.

The Tests after Completion shall be completed by the Contractor during the Defects Notification Period but not before the Section has operated on load for a period of 2 months after Take Over. It is expected that the performance acceptance tests will be completed within 10 months of first steam to set. If, due to causes not attributable to the Contractor, the tests do not take place in this period, ageing will be applied - Refer Section 12 for further details.

Any outage of the Section which is required by the Contractor during the Defects Notification Period shall, as far as is practicable, be arranged to suit the convenience of the Employer.

2.13.5 Not Used



2.13.6 Continued Availability of Skilled Engineer

From the time that The Employer commences to use any portion of the Works , whether taken over or not, up to 18 months after Take Over, the Contractor shall have available at not more than twenty-four (24) hours notice an operating representative who shall be a skilled engineer fully experienced in the operation of the type of Plant installed. The duties of such engineer will be to advise on the running of the Plant and he shall be capable of making and shall make adjustments and repairs to the Plant in case of breakdown. This engineer shall be continuously available on the Site during any period The Employer may require.

2.14 Testing of Turbine Generator Plant

Refer to section 12 and 13 and schedules C & D.

The factory tests and Site testing of the Works shall be carried out by the Contractor, or by an independent testing authority appointed by the Contractor and approved by the Engineer, in accordance with the requirements of Sections 12 and 13 of this Employer’s Requirements. Unless otherwise agreed by the Engineer in writing all works and site testing, specified in these two sections, shall be witnessed by representatives of the Employer, and, where applicable, the quality assurance requirements as specified.

The price includes for all necessary labour, materials, supply and calibration of instruments and other equipment to the Employer's satisfaction and any other items necessary to perform the tests.

Prior to the Contractor performing the acceptance tests he shall undertake any necessary preparatory work such as installation of special piping, blank flanges, etc., as part of this contract.

Regarding the provision by the Contractor of instrumentation and measuring points for the heat rate and other acceptance tests the Employer's requirements are specified in Section 12.2.11 and the Contractor shall take due cognizance of these requirements.

Should the Contractor be unable to undertake any of the specified tests or should he be unable to appoint an independent testing authority to do so he may approach the Employer with a request to undertake the testing on his behalf. The Employer will only do so should the capability exist at that time. Should the Employer be unable to undertake any testing on behalf of the Contractor, the Employer may appoint an independent testing authority to do so. Should this eventuality arise the Employer will inform the Contractor of the terms and conditions under which the Employer will perform the testing or appoint an independent testing authority to do so.

With regard to the performance of all or any of the Site tests specified in Section 12 the Employer reserves the right to nominate the tests which the Contractor or his independent testing authority shall undertake.

Should any Section or part thereof fail to pass any of the specified tests, the cost of subsequent repeat tests shall be borne by the Contractor in accordance with Particular Conditions sub clause 9.1 - Tests on Completion, irrespective of whether the tests



are carried out by the Contractor or his independent testing authority or by the Employer or the independent testing agency appointed by the Employer.

2.15 Foundations, supporting structures and miscellaneous fabricated items

2.15.1 Concrete Foundations and Plinths

All concrete foundations and plinths for the Works provided under this Contract shall be designed by the Contractor in accordance with the civil and building specification for the, turbine house and air cooled condenser, as detailed in section 14 and other data provided by the Contractor. The Contractor shall incorporate his designs into the complete civil design of the turbine house Plant and air cooled condenser. All designs are subject to approval by the Engineer.

These civil works relating to the Works will be constructed by the Employer. During such construction, the Contractor shall inspect and verify the position and dimensions but not the quality of the civil works. Upon completion of the civil works, or a part thereof, for handover to the Contractor, the Contractor shall carry out a final inspection for acceptance of the position and dimensions, but not the quality, of the civil works. The scope of such inspection, verification and final acceptance shall be defined in an agreed quality control schedule. This will be utilised in the sign off / hand over of the civil works relating to the Works.

2.15.2 Supporting structures

Refer to Section 14.

All steelwork relevant to the Works is the responsibility of the Contractor. All structural steelworks are to be supplied in accordance with the standards and codes listed in 14.1.5.3.

The design of the supporting structures for the main turbine generator, the boiler feed pumps, the deaerator, the feed-water heaters and the air cooled condenser shall be the responsibility of the Contractor. The turbine generator foundation table shall be based on rigid or untuned designs and the boiler feed pump foundations shall be based on a spring design. The design of the supporting structures shall provide for both static and dynamic conditions.

Suitably sized trenches shall be allowed for by the Contractor in the upper surfaces of concrete supporting structures for the turbine generator and the boiler feed pumps to accommodate pipes and electric cables. Under no circumstances shall pipes and electric cables be laid on top of these upper surfaces. The trenches intended for piping of oil or other flammable substances shall be sealed to prevent contamination of turbine under floor areas. The sealing arrangement shall also be fire proof.



The non-slip covers to these trenches and those for the oil channel alongside the turbine generators, which shall be supplied under this contract, shall not vibrate during the running of the main machinery.

Where cables, connected to Plant supplied under this Contract, require conduit pipe supports or trays within or affixed to the turbine generator, boiler feed pump, feed heater, air cooled condenser or other similar items of Plant, such cable conduit pipes supports or trays shall be designed and supplied under this Contract, to the Engineer’s approval.

All other cable support and trays will be supplied by the Employer.

2.15.3 Steel work, steel flooring, platforms, stairways, ladders, handrails and related items.

The Contractor is responsible for all steelwork required for supporting the works which includes all necessary flooring, trench covers and kerbing, platforms, stairways, ladders, handrails and related items, including all trimmer beams, stools, hangers and floor collars in steel flooring.

The load bearing surfaces of flooring, platforms and stairways shall be of the open-grid or non-slip types to the approval of the Engineer.

The Contractor shall be responsible for the provision of all temporary and permanent hand railing to all flooring, platforms, stairways and ladders, included in the contract, and around all openings or wells that occur within the works.

All hand railing for the works shall match. The Contractor shall supply handrailing according to the Employer’s standard handrailing drawing (Refer Schedule A.1-1 drawing number 00/2019). The hand railing shall be of the balustrade or mono-weld types manufactured to suit the Employer's requirements.

The design of steelwork, flooring and platforms shall be to the Engineer's approval. Stairways, ladders and hand railing shall conform to the requirements set out in the applicable standards in Schedule B.1-1.

The open edges of all flooring, platforms and wells shall be adequately protected by kick plates or toe-rails in conformity with the requirements of the South African OHS Act No.85 of 1993 as amended.

Provision shall be made for fixture of crawl beams and run ways for lifting equipment defined in clause 2.16 in the design of supporting structures. In areas where rigging of heavy equipment could interfere with installed flooring or platforms, the design and installation should allow for easy removal and re-installation of sections of the flooring or platform to facilitate maintenance-friendly lifting and rigging of heavy components.



2.15.4 Component lay-down areas

The Contractor shall supply specifications of all lay down areas for main components, both within and outside the turbine hall, required during maintenance. These are to be incorporated into general Plant arrangement and layout. The specification should include weight, dimensions and rigging requirements of components.

The component lay-down areas for larger spare components, with associated high level storage requirements should be specified Schedule H2, to be incorporated in layout of the stores system by the Employer.

2.16 Tools, special tools and equipment, lifting and handling tackle

Except as otherwise stated in Section 1.3, the Contractor shall supply a full set of special tools and equipment, lifting and handling tackle adequate for maintenance and complete overhaul of all Plant to be provided under this Contract . These items shall be of good quality, new when handed over to the Employer and shall be delivered to the Employer, in each instance before the item of Plant in question is commissioned.

Specialised tools, maintenance and inspection systems shall be designed, developed, procured and tested to the same requirements as defined for the Plant, and shall be delivered with the Plant.

Suitable lifting beams of the girder type shall be provided by the Contractor for turbine casings and rotors, the generator rotor and any other equipment within the Works for which a lifting beam is necessary.

Two 12.5 tonne semi portal cranes together with rails, shall be provided by the Contractor. (Refer to arrangement drawing)

The Contractor shall supply two 120 tonnes turbine house cranes fitted with 50 tonne auxiliary hoists which will be able to travel along the length of the turbine hall.

The Contractor shall supply a stator lifting device for installation of the generator stator. The generator stator is defined as the non-rotating part of the generator: meaning stator iron core, housing, coolers, etc. (does not include generator rotor or excitation equipment). The stator lifting device is to be refurbished and tested prior to Completion of all the units and handed over to the Employer.

For the removal and replacement of the bottom bearing halves of the turbine and generator rotors, the Contractor shall include suitable lifting jacks of adequate capacity. The bearing halves will be lifted by the Turbine Hall crane.

Chain blocks or similar lifting devices and crawls or runway trolleys of adequate capacity shall be included in the contract, together with associated crawl beams or runways in all areas of the Works where lifting and rigging of heavy equipment might be required. Crawls or runway trolleys should be permanently fitted to crawl beams or runways. Chain blocks may be moved only within one unit (Section) to the other units



(Sections). However sufficient chain blocks must be provided to enable effective and efficient maintenance work to be carried out. Details to be finalized during detailed design.

The Employer will make provision, where necessary, for the attachment by the Contractor of any of his runways or crawl beams to main platforms, building steelwork and other structures supplied by others.

To this end the Contractor shall provide the necessary design and other information as noted in the Key Dates Schedule.

One complete set of tube plugging equipment for heaters shall be provided. The Contractor shall demonstrate and prove the effectiveness of the equipment to the Engineer before it will be accepted

All necessary handling, withdrawal and lifting gear shall be included in the contract for the generator rotor, all coolers, deaerators, condenser and similar items including any special gear required for the preparation of turbine Plant for forced cooling.

Bolt tightening equipment of the hydraulic, or induction heating type for the assembly and removal of turbine cylinder and other bolts shall be included complete with all accessories including transformers where necessary. Where this equipment is of the electrical heating type, the rating and general features shall be to the approval of the Engineer. The Contractor shall include a suitable length of adequately protected flexible cable and plug connector for the supply of electric power to this equipment from a supply point to be provided by the Employer.

All lifting equipment, including slings and hooks, shall comply with the requirements of the South African OHS Act No.85 of 1993 as amended.

All lifting equipment to be refurbished and tested prior to completion of all the Sections and handed over to the Employer.

2.17 Balancing Facilities

Balancing facilities for turbine and generator rotors of mass up to 300 ton, (maximum length 23.5 meters and maximum rotor diameter 7 meters) will be available in the workshops of Rotek, Rosherville. Should the Contractor wish to make use of this facility for any reason, the Contractor is liable for the costs including the transportation to and from Rosherville.

All turbine and generator rotors shall be of such dimension and weight as to be capable of balancing in this facility. It is the responsibility of the Contractor to ensure that this is the case.

In the event that in the design of the Sections each rotor has only one journal, the Contractor shall provide a suitable stub-shaft or stub-shafts for adapting the rotors to the Rotek balancing machine. The sets of stub-shafts shall be supplied complete with coupling bolts. The set of stub-shafts for use in the balancing machine shall be purchased with the contract.



The rotors and bearings shall also be suitable for use with the brand and grade of oil used in the balancing machine. The stub-shafts shall be delivered before the end of the defects notification period for the first Section and will not be loaned to the Contractor for erection, maintenance or transport purposes.

2.18 Off loading and handling of the generator stator

The Contractor shall include for the design, supply and erection on Site, of suitable equipment for off-loading and handling the generator stator at the Project Site.

The equipment shall be complete in all respects, and suitable for off-loading the stator from road motor transport, either inside or outside the turbine house, transferring it into a position for hoisting to the level of the turbine generator table and placing in its final position on the table.

The Contractor shall provide adequate dimensional data and all major loads related to the installation of the generator stator.

Any civil design required for the lifting equipment is to be prepared by the Contractor and constructed by the Employer under the supervision of the Contractor.

After the Contractor has placed the generator stator in its final position he shall remove the off-loading and handling equipment to storage on site where it shall be maintained in satisfactory condition for re-use in connection with subsequent generator stators. The generator stator lifting device remains the property of the Employer.

The generator stator lifting device shall comply fully with the requirements of the South African OHS Act No.85 of 1993 as amended for lifting machines.

The Contractor shall provide a maintenance plan and specification for the maintenance of the stator lifting devices.

2.19 Operating and maintenance instruction manuals

The Employer’s requirements for operating and maintenance instruction manuals for power system Plant and equipment are detailed in Section 17 of this Employer’s Requirements. The Contractor shall produce the instruction manuals in compliance with Alstom standards (Refer document GGG/ 00/ EIS --- / IS/ 012 att 3B Project Operation & Maintenance Manuals) and any amendments thereto which are agreed between the Contractor and the Employer during the currency of the Contract .



2.20 Turbine generator Plant 3D Layout Models

The Contractor shall deliver to the Employer the following 3 Dimensional Computer generated software models:

i. A 3D layout model of the main foundations of the turbine generator unit

ii. A 3D layout model of the foundations of the boiler feed pumps.

The 3D model should be presented in a format which will allow presentation to selected forums in a conference room environment using a projector. These models shall contain sufficient detail features demonstrating the positions of all sleeves for holding down bolt and the passage of cables and integral piping, the location of trenches and openings in the main table and any slots or ducts which are to be incorporated in the tables. The models shall also include any intermediate integral floors to be constructed within the foundations.

iii. A 3D layout model of the turbine generator unit complete.

The 3D model should be presented in a format which will allow presentation to selected forums in a conference room environment using a projector. The model shall comprise all the main turbine generator, condensing and feed heating and air cooled condenser Plant items, all auxiliary Plant and boiler feed pump Plant and all important integral pipes, valves and other equipment. It shall be so constructed that it will serve both as a guide to construction of the Plant and as an aid in the training of operating personnel.

Note: Regarding integral pipes :

• branches above 2": all pipes detailed, all supports detailed into the model • branches between 1 and 2" (excluding 1", including 2"): all pipes detailed,

supports located but not detailed (but referring to a typical detail booklet). Pipes are prefabricable with the isometrics from the model.

• branches between 0 and 1" (including 1"): basic design done in the model, supports are not located nor detailed (but referring to a typical detail booklet)

If pipes are stress critical (temperature / pressure criteria), irrespective of the size, pipes and supports will be detailed into the model.

The Contractor shall illustrate progress on development of models at monthly intervals during development of the models.

The models will also be updated during construction to include all modifications to Plant as affected during the Works.



2.21 Plant codification & Labeling

Codification and labeling of all equipment and documentation supplied is part of the Works and is the responsibility of the Contractor.

Plant codification shall be in accordance with the KKS system and in accordance with the Employers specification Alpha KKS01, Alpha KKS02, NMP 45-7 (as amended in Section 17.3) and Section 17.3.

The KKS Plant codes generated by the Contractor shall be submitted to the Engineer for acceptance. The design freeze on KKS numbers is the second P&ID revision (KKS-Numbers shall be commented by the Engineer on the first P&ID issue).

KKS codes down to third level for equipment shall be used on documentation (e.g. drawings, manuals, equipment lists, cable schedules etc) as a unique identification means. References to Plant shall be accompanied by the relevant KKS code for that item of Plant.

Labeling includes the KKS code with English descriptions.

Abbreviations to descriptions on the labels shall be generally not acceptable. Where abbreviations shall be unavoidable, due to the limited number of characters that can be engraved/etched on labels, the abbreviations shall be in accordance with the Employer’s abbreviation standard (Alpha KKS02).

2.22 Flanges and joint rings

All terminal point flanges, supplied under this contract, shall comply with the requirements of EN standards or equivalent where selected by the Contractor and approved by the Engineer.

The minimum acceptable rating for these flanges shall conform to EN standards with 10bar rating. All flanges shall have machined, raised joint faces with the bolt holes drilled off-centre. The edge of and back faces of the flanges shall also be machined. The pitch circle of the bolt holes, the bore of the flange and the outside circumference of the flange shall be concentric. The joint rings for flanges shall not be less than 3 mm thick and shall be of a material suitable for the intended application.

The outside diameter of the joint rings shall be equal to the pitch circle diameter minus the diameter of the bolt holes. The inside diameter of the joint rings shall be at least 2 mm larger than the inside diameter of the pipe or valve but not larger than the outside diameter of the pipe.

2.23 Bolts, studs, nuts, washers and threads

The Contractor shall supply metric sizes, unless otherwise approved by the Engineer.

Where alloy or high tensile bolts or studs are used these shall be easily identifiable by means of stamping or engraving the ends.



The threads of all bolts and studs shall be cleaned and coated with a graphite-grease compound before assembly to prevent seizure.

2.24 Lubrication

All lubricants, including oils and greases shall be of local RSA supply from a single supplier, with common oils and greases for all units (Whenever feasible).

The Contractor is to draw up a lubricants schedule covering the entire works before any lubricant is delivered to site. The schedule includes the specifications of the lubricants. The schedules, specifications and a proposed supplier are submitted to the Engineer for approval.

The Contractors supply includes:

i. Lube oil and hydraulic control fluid (now common lube+ control oil system) for flushing of associated systems and initial fill of lube oil tank(s) and hydraulic control fluid tank(s) prior to first commissioning of unit.

ii. All lubricants for initial charge or lubrication of the works supplied under this contract.

iii. Lubricants, including turbine oil and hydraulic control fluid required for top up to maintain required tank- and lubricant levels or quantities during unit operation in the Proving Period as defined in Section 2.13.

2.25 Grease nipples and grease guns

All grease nipples supplied under this contract shall be of the hexagonal hook-on type to British Standard 1486 Type 11 or 21 or latest EN specification. For grease-lubricated motor bearings, see Eskom Standard Specification GGS 0802 (as amended) for motors. Subject to approval by the Engineer.

At least one grease gun, of not less than 2 kg of grease capacity, shall be provided for each type of grease nipple to be provided under the contract and for each grade of grease to be used.

A separate nipple shall be provided to serve each lubrication point and all grease nipples shall be readily accessible. Where a number of nipples supplying remote lubricating points are in use these are to be grouped together on a conveniently placed battery plate.

2.26 Thermal Insulation

All exposed parts of Plant, pipe work and valve bodies provided under this Contract, which convey steam, water, fuel exhaust products, air or gas at a temperature of more than 60°C, or as called for in the Eskom Specification for Thermal Insulation in Power Stations: NWS 1454, shall be suitably covered by insulation. The insulation shall comply



with NWS 1454 and additionally the Contractor shall comply with the provisions of the South African OHS Act No.85 of 1993 as amended, in respect of safety requirements.

As there is no final EN standard for Thermal Insulation for Power Stations yet, the Employer requires that the Eskom Specification NWS 1454 Rev 3 be followed.

However where the Contractor wishes to improve on the methods or materials specified in NWS 1454, this may be done with the Engineer’s approval.

The following sections in NWS 1454 must be amended:

1.) Section 8, Clause 8.5, Table:

First sentence is amended as follows: Vertical pipes and pipes at an angle greater than 350 to the horizontal shall be provided with supports (spider clamps) resting on lugs welded to the pipes, as shown in Figures 3 to 6.

Outer cladding must be securely attached to the clamp lying on the lugs.

The data in the table must be amended to the following:

Hot Face Temperature Material Spacing Maximum

Up to 2500C Mild Steel 6m

2510C to 3500C Mild Steel 5m

3510C to 5000C 15Mo3 or equiv 4m

5000C to 5700C 10CrMo910 or equiv 3.5m

2.) Figures 3 to 6 are amended accordingly (for the information detailed above).

Note that the surface temperature of insulated components shall not exceed 500C at an ambient temperature of 300C.

The Contractor provides easily identifiable re-usable removable sections of cladding and insulation over the welds on high pressure pipework. This is necessary to allow easy access for carrying out regular non-destructive testing of the welds. The design is to be submitted to the Engineer for approval.

LP turbine exhaust hoods and exhaust ducts will be insulated to the point where these ducts exit the turbine house wall. Warning signs and barriers shall be provided outside the turbine house where personnel can come into contact with the duct surface.

2.27 Rubber lining

See corrosion and protection specification Rev 0 dated March 2006.



2.28 Valves and other name plates and labels

Valve and other nameplates and labels shall comply with the Eskom Standard Specifications attached hereto in Schedule B.1-1.

Inscriptions shall be in English. Within twelve months of the award of the contract, the Contractor shall submit to the Engineer for approval comprehensive schedules and detail drawings of all nameplates and labels intended for the works.

Before manufacture of the nameplates and labels for the first set commences the Contractor shall submit to the Engineer for approval at least one specimen of each size and type of nameplate and label.

In all instances nameplates and labels shall be secured permanently before Plant is operated for a first time. Where removal of the nameplate or labels might be required to get access for maintenance, the fitting of the plate should allow removal and re-fitting. The Contractor’s methods of mounting name plates shall be subject to approval by the Engineer.

Manufacturer's plates for pressure vessels shall comply with the requirements of the South African OHS Act No.85 of 1993 as amended. However, the format of these plates shall be subject to the Engineer's approval before manufacture of these commences

2.29 Fire Protection

2.29.1 Scope

This document covers the minimum requirements for fire protection measures which the Contractor shall supply to achieve the following: • Minimize fire occurrence, both incidental and accidental, through passive fire protection. • Minimize losses in the event of a fire. • Maximize personnel safety. • Provide a layout of the Works which will facilitate fire fighting operations.

The installation of suitable fixed fire protection systems for identified risks, hazards and exposures are recommended. This is to ensure the fire safety of people, Plant and materials protection.

Fire prevention and fire fighting systems shall be in accordance with the South African current regulations on fire prevention and fire fighting services and the NFPA of America.

The primary hazard associated with the turbine-generator is the combustible oil used in large quantities.



The Contractor shall be responsible for the fire risk evaluation, system design, manufacture, installation and commissioning of a fully functional fire protection and prevention system.

The fire detection devices/systems are not in the scope of supply of the Contractor.

The Contractor shall supply the information required (number, location, required quantity, flammable substance) for others to fit their detection devices at the points specified, in terms of NFPA and the South African OHS Act, by the dates shown in Schedule IA 7/2

Each sprinkler system in the fire fighting system shall have a pressure switch to indicate when the system has been activated. The Contractor shall incorporate a nipple to the supply pipe(s) of each system to accommodate a pressure switch fitted by the Employer (C&I Contractor).

The Contractor who carries out the design and installation of the fire protection systems in the boiler and turbine contracts must be registered with ASIB (Automatic Sprinkler Inspection Bureau - see asib.co.za).

2.29.2 Interfaces

The Employer shall supply a fire water header in the auxiliary bay between the boiler and turbine house which will be supplying water at 10 bar pressure. A tap-off from this header will be provided to each turbine unit. The termination point on the tap-off will be at the discharge flange after an isolation valve as described in Section 1.3.18 – Terminal points.

The Contractor shall supply a connection from the turbine ring main to the generator transformer fire protection system (to be supplied by Others) at each Section.

The fire protection system will also be used for floor washing at 0m level in the turbine hall. The Contractor supplies 2 connections for floor washing at each Section. The details of the type of connections and the locations to be finalised with the Engineer during detailed design.

2.29.3 General Requirements

A fire risk evaluation shall be carried out by the Contractor and given to the Engineer for approval as basis of the future design. The evaluation should result in a list of recommended fire prevention and protection features to be provided, based on acceptable means for isolation or control of common and special hazards, the control or elimination of ignition sources, and the suppression of fires.

The following areas, at least, shall be analyzed by the Contractor:

• Turbine-Generator

• Hydrogen System

• Hydrogen Seal Oil Pumps and System



• Hydraulic Control System

• Lubricating Oil Systems

• Turbine-Generator Area

• Areas beneath turbine-generator operating floor subject to oil flow, oil spray or oil accumulation.

• Turbine-Generator Bearings

• Exciter

• Oil Storage Areas

• Cable tunnels

• Transformers in the Works

Fire protection will be specified for all areas included in the entire turbine house as well as ACC area and CEP Building part of the turbine contract.

This list shall not be considered exhaustive and any other hazardous areas or systems considered necessary by the Contractor shall be analyzed and indicated to the Engineer.

The Contractor shall supply the Engineer with an estimation of the required fire system flow requirements and exact flow requirements within the time required by the Contract.

The complete fire system quality control shall be done in accordance with NFPA requirements. Upon installation, all fire protection systems should be pre-operationally inspected and tested in accordance with applicable NFPA standards.

After the approval of the fire risk evaluation the design of the fire protection system will commence. All designs shall be provided to the Engineer for approval, prior to commencement of manufacture and installation.

The fire protection piping system shall be designed by the Contractor to incorporate a ring main around the turbine unit supplying all fire protection systems.

Water hydrants will be provided at important positions. The nozzles and hoses are placed properly in fire equipment boxes.

Portable extinguishers will be furnished at appropriate positions in the Turbine Hall and Acc area as needed

All piping shall be designed at 120% of design capacity to make provision for possible expansion in future.

The Contractor installs a protective covering over all flanged or screwed joints or any section classified as a potential pressurized oil release point in order to deflect potential high pressure sprays of combustible oil away from adjacent plant. No protective



covering is required where joints are fully welded. Gravity fed return lines are excluded as a joint on these lines does not constitute spray hazard.

The Contractor’s design specifies the type of covering per oil release point to be either a spray guard shield, a barrier, or a spray hood and is designed in accordance with ASTM 1138- 98, “Standard Specification for Spray Shields for Metal Joints”.

2.29.4 Applicable Codes and Standards

Refer Schedule B.1-1.

2.30 Environment

The Works will be suitable in all respects to work under the various conditions of operation as described herein and under the climatic conditions at the Project Site.

2.31 Vibration, Shock and Noise

2.31.1 Vibration and Shock (See Section 12)

(a) Rotating Machinery

The standard for assessment of allowable bearing vibration of rotating machinery will be in accordance with ISO7919 and ISO 10816 Zone “A”.

The Plant shall run without exceeding the vibration limits specified, at all loads. (Refer ISO7919-2, paragraph 4.4.2 and more specifically par 4.2.4.3)

The vibration will be assessed in accordance with the latest issue of ISO7919 and ISO 10816 Zone “A”, and will not exceed the limits of the "good" assessment level under normal operating conditions.

(b) Plant and Equipment - General

Plant and equipment shall be designed and constructed to:

(i) Eliminate or reduce the incidence of vibration generated by internal components, e.g. as in safety valves, control valves, by-pass valves and similar devices.

(ii) Withstand the effects of vibration induced from other sources e.g. piping connecting to and structural steel supports or rotating and/or oscillating machinery, and

(iii) Withstand the effects of vibration and/or mechanical or thermal shock induced internally, e.g. as in blowdown vessels, by-pass steam dumping devices, etc.



Specific requirements applicable to the above are in the appropriate section of this Employer’s Requirements or in the attached standards or codes (see Schedule B.1-1).

Vibration of the condensing Plant structure will not exceed the recommendations given in DIN 4150 Parts 1, 2 and 3 or revised EN standards.

2.31.2 Limiting Value for Noise Generation

Near field noise levels are to comply with the SANS – South African National Standards and OHS act requirements.

No acoustic lagging will be provided underneath the operating floor for the turbine cylinders.

Guidelines and Standards

Planning and design for noise control installations shall meet the requirements of SANS10083 and SANS10103 (latest edition) noise levels. Due regard, as necessary, shall be given to the noise levels emitted from the rest of the power station or until known, reasonably anticipated to be emitted from the power station.

Below the ACC platform at ground level the sound pressure level of Lp<85dB(A) shall be achieved.

For items of plant which operate periodically or intermittently and by their nature emit severe noise, (Flash-tanks, flash-tank blowdown pipe outlet, Safety valves, Safety valves blow-down pipe outlet, Leak-off valves, Control valves, etc) the required noise levels when active shall not exceed any of the following: Area 1: 100 dB(A) at a distance of 5m from the item. Area 2: 90 dB(A) at the nearest point where personnel may be required to spend

time either maintaining, operating or adjusting equipment, for periods of not more than 4 hours in a day.

Area 3: 85 dB(A) at the nearest point where personnel may be required to spend time either maintaining, operating or adjusting equipment, for periods exceeding 4 hours in a day.

Areas 1 and 2 shall be marked as “Noise Zones” in line with the relevant standards. The Contractor guarantees the noise level in Schedule C (Also refer Section 12).



The Contractor performs a noise level survey as described in section 12.3.7.

2.32 Welding

The welding of all pipe work and specials will be carried out in accordance with the provisions of the latest EN standards. See also section 10.

2.33 Corrosion Protection and Painting

See corrosion and protection specification Rev 0 dated March 2006.

2.34 Chemical Dosing and Monitoring (Sampling)

The Unit(s) shall operate under what is now being termed an Alkaline Oxidising Treatment (AOT) regime, which is a modified Combined Oxygen Treatment (COT) regime, and shall comply with the requirements laid down in the Eskom Generation Standard GGS 0209, latest revision.

In accordance with the requirements of such a regime, only oxygen and ammonia shall be dosed to the circuits. The condensate reserve tanks shall be nitrogen blanketed, and preferably sparged, to prevent air ingress.

Chemical dosing and sampling systems shall be provided to enable compliance with and monitoring of adherence to the requirements of this treatment regime.

The Contractor shall provide equipment that can deliver a guaranteed condensate dissolved oxygen concentration of 20 µg/kg (as O2) maximum. Further reductions in the condensate dissolved oxygen shall be achieved by operational measures.

2.34.1 Chemical Dosing

As indicated, the Unit shall be operated under an Alkaline Oxygen Treatment (AOT) regime. The oxygen dosing point(s) shall be suitable for gas injection.

Oxygen shall be dosed into the discharge line(s) from the Condensate Extraction Pumps (CEP’s).

The principal location for the addition of ammonia shall be into the suction line of the CEP’s.

Provision shall be made for the dosing ammonia into the feedwater tank, the Air-cooled Condenser Condensate Collecting Tank (ACCCT) and the Condensate Reserve Tank (CRT). The feedwater tank and ACCCT dosing points shall be used principally during start-up, while the CRT dosing point shall be used after demineralised water make-up to the CRT.



Chemical dosing equipment shall be supplied by the Employer. Nozzles or injectors for dosing will be provided as free issue items by the Employer. Only the injection points and isolation valves to which the dosing lines shall be connected shall be provided by the Contractor.

As indicated, the CRT shall be maintained under a nitrogen blanket and preferably sparged to prevent/minimise air ingress during operation. The Contractor shall provide a connection for the nitrogen supply. As the water level falls in the CRT, the nitrogen supply shall increase to fill the gas space. As the water level in the CRT rises, nitrogen shall be expelled. The CRT shall be protected against over pressurisation and vacuum.

The locations of Chemical Dosing points for normal operation are clearly marked in the attached block diagram, Drawing 84/62.

2.34.2 Lay-up/Preservation/Storage

For short duration outages the Units shall be stored wet. The dosing points provided for normal/start-up operation are sufficient for the introduction of preservation chemicals. Any plant items within the condenser/ condensate/ feedwater/ boiler path that cannot be completely water-filled shall be nitrogen capped. The Contractor shall provide suitable connections for nitrogen capping of these items.

For longer duration outages, dry storage shall be practised. The Contractor shall provide drying equipment and connection points for dry storage. The Contractor shall identify any items of equipment that cannot be completely drained during longer duration outages.

2.34.3 Chemical Monitoring (On-line Analyses and Sampling)

Chemical monitoring shall be carried out in accordance with the surveillance requirements of the Eskom Generation Standard GGS 0209, latest revision, and EPRI Guideline 1004925 “Cycle Chemistry Guideline for Fossil Plants: Oxygenated Treatment”, Final Report, March 2005.

Both remote (transmitted to sample room) and local (typically sited in the field at nearest pillar) samples shall be extracted from the system to verify that chemical conditions and impurities are within the limits set in GGS 0209

Remote samples shall typically be conditioned with respect to flow, temperature and pressure before presentation to an on-line chemical analyser for continuous, semi-continuous, discontinuous monitoring. Provision shall also be made for the collection of grab samples for laboratory analyses. Local sample points shall typically be used for diagnostic purposes and cooling water and power outlets shall be conveniently located to allow safe handling and the temporary connection of a chemical monitor for on-line analysis.

Samples shall be extracted at the locations illustrated in Drawing 84/62 and detailed in Table 2.34.1. The physical location of a sample point in a length of



piping or on a vessel shall be agreed between the Contractor and the Engineer prior to any installation.

The remote sampling and conditioning equipment and local sampling equipment shall be supplied by the Employer.

The sample point transition stubs shall be provided by the Contractor to the Employer’s specifications.

The Employer shall provide the sample probes/nozzles, isolation valves (double isolation for high-pressure/ high-temperature {HP/HT} samples, single isolation valves for low-pressure/ low-temperature {LP/LT}) and interconnecting piping. The HP/HT sample nozzles shall comply with the requirements for isokinetic sampling as given in EPRI report TR-100196, “Development of a Steam Sampling System”.

The Contractor shall install the sample probes/nozzles, isolation valves and interconnecting piping provided by the Employer. Where possible sample points/ isolation valves shall be installed in accessible locations. If the sample point/ isolation valves are not in accessible locations, the Contractor shall install a suitable platform and stairs.

The turbine condensate drains are collected in the turbine condensate drains tank. From here the turbine condensate drains are either returned to the air-cooled condenser condensate tank or to the water treatment plant, depending on water quality. Discharge is initiated by a level control switch. The conductivity of the water in the tank is continuously measured to monitor water quality. The conductivity probe is installed on a continuous mini-recirculation loop. The inlet to this loop shall be on the main outlet pipe from the tank, upstream of the turbine condensate drains tank discharge pumps. Sample recirculation pumps (2 x 100%) shall supply a sample stream (2.5 L.min-1) to the conductivity probe. The mini-recirculation loop is returned to top of the turbine condensate drains tank.

The Contractor shall supply the mini-recirculation loop, including recirculation pumps, isolation valves and interconnecting piping, but excluding the conductivity probe and housing. Swagelok™-type quick connects shall be provided for the inlet and outlet of the conductivity probe housing.

The Employer shall supply the conductivity probe housing and conductivity monitoring equipment , including the probe(s).




Table 2.34.1 : Chemical Sampling and Dosing Sections (f - k to be completed by the Contractor) Service

(Source Stream)

(a)

Number of Sample Points

(b)

Associated On-line Chemical Monitors

(c)

Sample Probe Type

(d)

Transition Joints to be

Supplied Under this Contract

(e)

Sample Stream Flow

(L.min-1)

(f)

Source Stream Temp.

(°C)

(g)

Source Stream Press.

(MPa)

(h)

Source Stream

Pipe Diameter

(mm)

(i)

Source Stream

Pipe Wall-

thickness

(mm)

(j)

Source Stream

Pipe InsulationThickness

(mm)

(k)

Source Stream Pipe Material

Make-up Water (Unit 1 Only) One (1) Κ25 : CC25 : IC # Stub see GGG 1205 2.5 Air Cooled Condenser Dump One (1) Local - Diagnostic Stub see GGG 1205 1 Air Cooled Condenser Collector Headers

One (1) per header, joined to common manifold

Local - Diagnostic Stub see GGG 1205 1

Air-cooled Condenser Condensate Collector Tank Outlet

One (1) Degas : pH25 : NH3 #: O2

#: SiO2

# : Na+ # : IC #W1 see GGG 1205 2.5

Condensate Reserve Tank Outlet One (1) Local - Diagnostic W1 see GGG 1205 1 Condensate Polishing Plant (CPP) Common Inlet


#: SiO2

# : Na+ # : IC # : CPS (TSS & Fe)

W1 see GGG 1205 2.5

CPP Pre-polishing Filter Outlet (common outlet manifold)

One (1) CPS (TSS & Fe) W1 see GGG 1205 1

CPP Cation Unit Outlet One (1) per IX bed (i.e. 3 per Unit total)

Κ25 : Na+ # : IC # W1 see GGG 1205 2.5

CPP Anion Unit Outlet One (1) per IX bed (i.e. 3 per Unit total)

Κ25 : CC25 : SiO2 # : IC # W1 see GGG 1205 2.5

CPP Common Outlet One (1) Degas : O2 #: SiO2

# : Na+ # : IC #

W1 see GGG 1205 2.5

Condensate Extraction Pump Discharge


#: SiO2

# : Na+ # : IC #W1 see GGG 1205 2.5

Feedwater Tank Inlet One (1) Local - Diagnostic W1 see GGG 1205 1 Feedwater Tank Outlet One (1) O2

# Stub see GGG 1205 1 Economiser Inlet † Two (2), set at 180° to each

other, in each economiser feed line

Degas : pH25 : NH3 #: O2

#: SiO2

# : Na+ # : IC # : CPS (TSS & Fe) ‡

EPRI-Isok As per OEM 2.5

Boiler Circulating Pump Discharge Two (2) set at 180° to each other, located on the discharge of the boiler circulating water pump

CC25 : IC # EPRI-Isok As per OEM 2.5

Superheated Steam Outlet Header One (1) in each outlet leg from collection header to turbine (max 2)

Degas : SiO2 # : Na+ # : IC

# : TOC EPRI-Isok As per OEM 2.5

Hot Reheat Outlet Header One (1) in each outlet leg from collection header to turbine (max 2)

CC25 EPRI-Isok As per OEM 2.5

HP Heater Distillates One (1) per heater (i.e. 4 total) Local - Diagnostic W1 see GGG 1205 1 Boiler Steam Feed Pump Turbine Condensate (only if BSFP installed)

One (1) CC25 W1 see GGG 1205 2.5

Turbine Condensate Drains Tank (in recycle loop)

One (1) CC25 W1 see GGG 1205 2.5

LP Turbine Hood Spray One (1) CC25 W1 see GGG 1205 2.5 Notes: # instruments may be shared between sample points of same unit † The sample point shall be located after desuperheater spray water take-off but before any recirculation line return (vertically mounted) at least 10 pipe diameters downstream and 5 pipe diameters upstream from any bend and upstream

of any chemical injection point ‡ The economiser CPS instrument is mounted on the primary cooler panel immediately downstream of the primary cooler.


Key to Table 2.34.1:

pH25 = pH measurement, sample conditioned to 25°±0.5°C CC25 = Acid or Cation Conductivity, µS.cm-1, sample

conditioned to 25°±0.5°C K25 = Specific Conductivity, µS.cm-1, sample conditioned to

25°±0.5°C Degas = Degassed Cation Conductivity, measurement

incorporates CC25 and K25, µS.cm-1

IC = Ion Chromatography Na+ = Sodium NH3 = Ammonia SiO2 = Silica O2 = Dissolved Oxygen CPS = Corrosion Product Sampler TSS = Total Suspended Solids Fe = Iron TOC Total Organic Carbon EPRI Isok = EPRI-type isokinetic sample nozzle (including double

isolation valves) W1 = W1-type sample nozzle as described in Eskom

Guideline GGG 1205 Stub = Stub-type sample collector as described in Eskom

Guideline GGG 1205

2.35 Alternative Offers for Identified items.

Not Used.


Turb.sect2.Gen Spec 19Sept07

Documents

gen spec 19sept07

typical detail

medupi power

air cooled

fire risk

conference

defects notification

miscellaneous