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Conversion of Qurrayah Open Cycle Power Plant

To Combined Cycle Power Plant , Project C

Method Statement For CW Screen Wash Water

Piping System Flushing Block 1,2,3,4 &5

Doc.No : 306211127-000-4PR-00 REV.: 00 DATE : 01 AUGUST 2012

Pg 1 Saudi Electric Company| Arabian Bemco Contracting Co. Ltd.

Check list for Method Statement:

METHOD STATEMENT FOR CW SCREEN WASH WATER

PIPING SYSTEM FLUSHING , BLOCK 1234 5

No. Items

Checked ByContractor BeforeSubmitting forApproval

Checked By SEC/LIwhen Received

1

Name and detail of personfrom contractorresponsible for the

supervision of works.

Page-5: Paragraph 5

2

Brief Description of thework to be carried out.(detail methodology underitem 12)

Page-5: Paragraph 1

3

Detail Program of workshowing timing, sequenceand order of activities ondaily basis.

N/A

4

Plant and ResourceUtilization (Listing dailyusage of Plant and

Resource for the period ofworks.)

N/A

5

Identification of work Area(sketch, showing operationarea, storage area, vehicleand plant movement area).If any crane or liftingequipment are used Jibradius and lifting plan.

N/A

6Access and egress to workarea (sketch indicatingboundaries of work area).

N/A

7Proposed Method ofcordoning and fencing ofthe work area (sketch).

N/A

8

Provision of access to PlantOperators and pedestrianthrough the work area ifrequired (sketch indicatingaccess routes).

N/A

9Provision of reduction ofnoise, dust, vibration andother pollutions.

N/A


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10

Provision of protection ofexisting plant and

installation from damagefrom adjacent constructionactivities (sketch).

N/A

11

Provision of temporarywork at the necessarycalculations for shoring ofexisting foundation,structure adjacent toconstruction works(drawings and calculationssheets).

N/A

12

Detailed description of the

Methodology of carryingout the works.

Page-5 to 8: Paragraph8

13Emergency and safety planspecific to the work place.

Page-5: Paragraph 7

14 Risk assessment Page-4: Paragraph 6

15Requirement of all therelevant permits.

N/A

16 Inspection and test plan. N/A

ForContractor: For SEC/LI:

Name: Name:

Date: Date:

Signature: Signature:


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T BLE OF CONTENTS

Pages

Checklist for Method Statement

1. SCOPE 4

1-3

2. DEFINITIONS 4

3. APPLICABILITY 4

4. EFFECTIVE DATE 4

5. RESPONSIBILITIES 4~5

6. SAFETY 5

7. PREPARATION FOR FLUSHING 5

8. FLUSHING PROCEDURE 6~7

9. RESTORATION 7

10. TEMPORARY EQUIPMENT &

MATERIAL LIST 8

11. ATTACHMENTS 8~9


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METHOD STATEMENT FOR

CW INTAKE SCREENS WASH WATER PIPING SYSTEM FLUSHING

( BLOCK 1,2,3,4 5 )

1.

The scope of work for flushing shall be limited to the identification of, and the definition

of the system to be flushed. Flushing pressure will be at minimum 3bars @approximately 0.9 m/s .The preparation of detailed flushing plans for each system,supervision of execution of the activity, followed by inspection and acceptance of thecompleted work.

SCOPE:

2.

As a pre-commissioning activity, flushing can be defined as the act of pumping water, insufficient quantity and velocity, through a given section of pipe or piping, such that theflow of water through the system will forcibly remove any loose rust, mill scale orconstruction debris from the system.

DEFINITIONS:

3.

This Work Instruction shall be applied to Qurayyah Combined Cycle Power Plant for CWScreen Was Water System Piping , Block 1234&5.

4.

APPLICABILITY:

EFFECTIVE DATE:

This work Instruction will take effect from SEC/LI approval issuing date.

5.

Engineer/Superintendent/Supervisor shall be responsible for site activities and

implementation of Quality and HSE plan during construction. Also, responsible for

coordination and management of all equipment related activities at site.

RESPONSIBILITIES:

5.1 Construction Manager/Area Manager

The Construction Manager/Area Manager shall be responsible for thecoordination and management of all erection activities at site and coordination withthe client/other contractor.

5.2 Engineer/Superintendent/Supervisor


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5.3 QA/QC Manager, QA/QC Inspector

QA/QC Manager shall be responsible for all QA/QC activities of all project. He shall beinteracting with QA/QC manager of client related to all mechanical activities and heshall be responsible for Non conformance management. QA/QC inspector shall beresponsible for site QA/QC activities, coordination with client for all equipmentinspection activities.

5.4 H.S.E Manager/Safety Officer

HSE Manager takes responsibility of all HSE activities at site. Safety Officer shallensure that work is carried out in safe manner and also ensure that toolbox talksmeeting are conducted by concerned supervisor and shall ensure proper mode ofcommunication in case of emergency.

6. SAFETY:

Barricade all the piping , systems , circuits or sections which is going to be

flushed.

Keep a safe distance for flushing crew.

Release all the air that are trapped in the piping system , circuits or sectionsand ensure that it is filled with water only.

7.

Temporary Loop

PREPARATION FOR FLUSHING

7.1 Complete items on System Flushing Checklist from ITP, including clearanceby Construction, quality and safety.

7.2 Use marked-up P&ID drawing of the system for the flushing package toprepare the system for flushing.

Attachment drawing with temporary loop marked will be provided. Design Parameters

Marked-up will be done. Valve Position

Valve position in the drawing will be highlighted and attached. Temporary Strainer Specifications

Conical Type Strainer, Stainless Steel , 3mm wire mesh will be usedin this procedure.

Bill of MaterialsLists of temporary materials will be attached on the system that willbe flushed.

7.3 Remove all orifices and isolate all instrumentations7.4 Make by-pass arrangements per the flushing P&ID.7.5 Check the inline equipment which has to be removed for flushing and

replaced with temporary spool.


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7.6 Fabricate temporary spools piece, gaskets, blanks and blind flanges where itis required.

7.7 Remove all sensing line of the self regulating pneumatic valve during flushing.7.8 Pumps to be used for temporary or permanent must have the proper power

supply or petrol if manually operated will be use for flushing the system.7.9 Change pump suction strainer and of equipments to temporary strainer.7.11 Check all pipe supports and pipe shoes are properly installed.7.12 Make a walk-down on the system to be flushed with Safety , Quality and

Construction to confirm everything is set-up as planned.7.13 Check that the working area cleaned and free from any safety hazard.7.14 Once all the preparation and checking works are completed, flushing package

System is ready for water filling.

8.

8.1.1 Flushing Medium

FLUSHING PROCEDURE :

Potable water or plant water as approved shall be used as flushingmedium.

8.1.2 Flushing Steps

Flushing of the system shall follow these steps:

8.1.3

Water filling should be carried out in the system, during the filling of water, thevent valve should be in open position to release the air inside the pipe and itshould be located at the highest point of the flushed system. To ensure thesystem is properly filled with water, the filling should be carried-out until wateroverflow from the vent valve. Once the pipes are filled then close the ventvalve.

8.1.4 Preliminary checks of the system has to be carried out initially by gravityflushing to remove dirt, dust, sand and other debris by opening one end of thesystem preferably the connection before the filter.

8.1.5 Start the flushing pump and check any flange joint leaking, tighten the bolts

until leakage stop. Any leak on laminated joint, adhesive bonded joint, butt &wrap lamination joint, put a mark on these joint to identify for the repair work.Before starting the repair work of the leaked joint, the pressure in the systemhas to be released and drain out of the water.

8.1.6 When the repair works has been completed then starts to refill water into thesystems as per step 1 and recheck all the joints to ensure that the leaks arearrested. Re-start system flushing.

8.1.7 Continue flushing the system to achieve the required acceptance criteria, keepnote on the frequency of the filter cleaning.


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8.1.8 The flushed water will be discharge on the temporary drain line as shown onthe attached marked up P&ID or by connecting to a Fire hose 80mmdia androuted to the nearest floor drains in the structure or to safe location in thearea.

8.1.9 Process for Flushing Inspection

The flushing of the system will be carried out in the presence of the ClientRepresentative and the QA/QC engineer who will witness the result of theflushing for signature acceptance. The whole process is to be recorded andwill be signed by all the witness party.

8.1.10 Submit RFI for the line check prior to flushing. Include flush boundaryhighlighted P&ID.

8.1.11

Joint site walk-down with client.

8.1.12 Create punch lists for Flushing.

8.1.13 Clear punch lists (by Construction).

8.1.14 Submit RFI for flushing piping system. Conduct flush.

8.1.15 Complete and sign System Flushing Report from ITP.

8.1.16 Submit Flush Records to Commissioning to include in Documentation Package.

8.1.17Acceptance Criteria

In general , for a period of not less than 5minutes a clear water (with NO

8.1.18 Flow Measurement

dirt, sand ,debris or foreign objects ) must be discharged.

Flow will be calculated based on pump discharge pressure and pump curve.

9.

After flushing is completed, system should be thoroughly drained with all highpoint vents open.

RESTORATION :

Remove the temporary spools and reinstall all inline equipment which havebeen removed for flushing and replace all temporary gaskets and make readyfor operation.

10.

S. N.

List of Temporary Equipment Materials :

Description Size Quantity Remarks

1 Diaphragm Metering Pump: 2 nos.


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Q=980 liters/m; H=20 Meter;

=80mm; Pmax=10bar

2 Water Supply Tanker

5 m3 capacity

1 nos.

3 Flexible Hose pipe 10 meters

length, 80mm size with flange

5nos.

4 Temporary bolts and gaskets To be supplied invarious sizes andrating

5 Manual pressure pump 1 no.

6 Vents and Drain valves As required

7 Leather Hand Gloves L, XL 12 pairs

8 Cotton Gloves L,XL 12nos.

9 Safety Goggles 5 nos.

10 Calibrated Pressure Gauge0-10 bar

2 nos.

11 Hose Clamps for 80 mm hose 10 nos.

12 All Temporary Spools and tools As required.

13 100mmdia Temporary Conical

Strainer , SS, 3mm mesh

10 nos.

11.

System Flushing Check lists from ITP

ATTACHMENTS :

ITP No.: 30621127-000-4QC-015-000

System Flushing Report from ITP

ITP No.: 30621127-000-GIP-00027/000

Marked-Up P&ID QCCPP ,CW Screen Wash Water Piping System

EE- 01991 sh.01 ~ 04 rev.E

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