NES 387 Chemical Cleaning of Chilled Water System Category 2

Requirements for Chemical Cleaning ofChilled Water Systems for HM Surface

Ships, Submarines and Royal FleetAuxiliary Vessels

Ministry of Defence Defence Standard 02-387

Issue 2 Publication Date 21 December 2001

Category 2

AMENDMENTS ISSUED SINCE PUBLICATION

AMD NO DATE OFISSUE

TEXT AFFECTED SIGNATURE &DATE

Revision Note

This Issue of this Standard has been prepared to incorporate changes to text and presentationand remove the Limited Distribution status. The technical content has been updated in linewith current practice.

Historical RecordDef Stan 07-223/Issue 1 1 April 2000Def Stan 02-387/Issue 1 1 April 2000NES 387 Issue 1 June 1997

DefenceProcurementAgencyDefence StandardizationRm 1138Kentigern House65 Brown stGlasgow G2 8EX

Helpdesk: 0141 224 2531Facsimile: 0141 224 2503

e-mail: [email protected]

21 December 2000

Defence Standard Number: 02-387 Issue 2

It is MOD policy that standards should not give significant advantage to theproducts of any supplier. However this standard contains details ofmanufacturers which are included at the request of the sponsor for safety reasons.These details were correct at the time the standard was written but details mayhave changed. The standard is published on an interim basis until 31 May 2002by which time the Naval Defence Standards Policy Committee will have issuedfurther guidance on the future inclusion of manufacturers details in Naval DefenceStandards.

Neil G LangUK Defence Standardization

DPA

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DEFENCE STANDARD 02387 (NES 387)

REQUIREMENTS FOR CHEMICAL CLEANING OF CHILLED WATERSYSTEMS FOR HM SURFACE SHIPS, SUBMARINES AND

RFA VESSELS

ISSUE 2

This Defence Standard is

authorized for use in MOD contracts

by the Defence Procurement Agency and

the Defence Logistics Organization

Published by:

Defence Procurement AgencyAn Executive Agency of The Ministry of DefenceDirectorate of StandardizationKentigern House65 Brown StreetGlasgow G2 8EX

DEF STAN 02387/Issue 2(NES 387)

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SCOPE1. This Defence Standard (NES) specifies the requirements for flushing, chemical cleaning and

inhibiting of chilled water systems on HM Surface Ships, Submarines and Royal FleetAuxiliary (RFA) vessels.


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FOREWORD

Sponsorship1. This Naval Engineering Standard (NES) is sponsored by the Defence Logistics Organization

(DLO), Ministry of Defence (MOD).

2. Any user of this NES either within MOD or in industry may propose an amendment to it.Proposals for amendments that are not directly applicable to a particular contract are to bemade to the publishing authority identified on Page(i), and those directly applicable to aparticular contract are to be dealt with using existing departmental procedures.

3. If it is found to be unsuitable for any particular requirement, MOD is to be informed in writingof the circumstances.

4. No alteration is to be made to this NES except by the issue of a formal amendment.

5. Unless otherwise stated, reference in this NES to approval, approved, authorized and similarterms means by the MOD.

6. Any significant amendments that may be made to this NES at a later date will be indicatedby a vertical sideline. Deletions will be indicated by 000 appearing at the end of the lineinterval.

7. Extracts from British Standards within the NES have been included with the permission ofthe British Standards Institution.

8. This NES has been reissued to reflect changes in departmental nomenclature and the changesto technical requirements.

Conditions of Release

General9. This NES has been devised solely for the use of the MOD, and its contractors in the execution

of contracts for the MOD. To the extent permitted by law, the MOD hereby excludes allliability whatsoever and howsoever arising (including but without limitation, liabilityresulting from negligence) for any loss or damage however caused when the NES is used forany other purpose.

10. This document is Crown Copyright and the information herein may be subject to Crown orthird party rights. It is not to be released, reproduced or published without written permissionof the MOD.

11. The Crown reserves the right to amend or modify the contents of this NES without consultingor informing any holder.

MOD Tender or Contract Process12. This NES is the property of the Crown. Unless otherwise authorized in writing by the MOD

it must be returned on completion of the contract, or submission of the tender, in connectionwith which it is issued.

13. When this NES is used in connection with a MOD tender or contract, the user is to ensure thathe is in possession of the appropriate version of each document, including related documents,relevant to each particular tender or contract. Enquiries in this connection may be made tothe authority named in the tender or contract.

14. When NES are incorporated into MOD contracts, users are responsible for their correctapplication and for complying with contractual and any other statutory requirements.Compliance with an NES does not of itself confer immunity from legal obligations.


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Categories of NES15. The Category of this NES has been determined using the following criteria:

a. Category 1. If not applied may have a Critical affect on the following:

Safety of the vessel, its complement or third parties.

Operational performance of the vessel, its systems or equipment.

b. Category 2. If not applied may have a Significant affect on the following:

Safety of the vessel, its complement or third parties.

Operational performance of the vessel, its systems or equipment.

Through life costs and support.

c. Category 3. If not applied may have a Minor affect on the following:

MOD best practice and fleet commonality.

Corporate Experience and Knowledge.

Current support practice.

Related Documents16. In the tender and procurement processes the related documents listed in each section and

Annex A can be obtained as follows:

a. British Standards British Standards Institution,389 Chiswick High Road,London, W4 4AL.

b. Defence Standards & Defence Procurement Agency,Naval Engineering Standards An Executive Agency of the Ministry of Defence,

Directorate of Standardization,Kentigern House,65 Brown Street,Glasgow, G2 8EX.

c. Other Documents Tender or Contract Sponsor to advise.

17. All applications to Ministry Establishments for related documents are to quote the relevantMOD Invitation to Tender or Contract number and date, together with the sponsoringDirectorate and the Tender or Contract Sponsor.

18. Prime Contractors are responsible for supplying their subcontractors with relevantdocumentation, including specifications, standards and drawings.

Health and Safety

Warning

19. This NES may call for the use of processes, substances and/or procedures that may beinjurious to health if adequate precautions are not taken. It refers only to technical suitabilityand in no way absolves either the supplier or the user from statutory obligations relating tohealth and safety at any stage of manufacture or use. Where attention is drawn to hazards,those quoted may not necessarily be exhaustive.

20. This NES has been written, and is to be used, taking into account the policy stipulated inJSP430: MOD Ship Safety Management System Handbook.


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Additional Information21. Particular attention is drawn to the following hazards, although the list may not be

exhaustive:

a. Chemical Hazards. Injury or damage to health may be caused by contact, ingestion orinhalation.

b. Electrical Hazards. Injury or damage to health may be caused by contact with hazardousvoltages, breakdown of insulation, leakage of current etc.

c. Mechanical Hazards. Injury or damage to health may be caused by excessive noise,vibration, or risk from laceration, etc.

National Legislation22. The work of flushing, chemical cleaning and inhibiting chilled water systems is to comply

with:

a. Health and Safety at Work Etc Act 1974;

b. Control of Substances Hazardous to Health Regulations (COSHH)SI No 437;

c. The Construction (Design and Management) RegulationsSI No 3140;

d. Management of Health and Safety at Work RegulationsSI No 2051;

e. Provision and use of Work Equipment RegulationsSI No 2306;

f. The Water Resources Act 1991;

g. Local Water Authority requirements;

h. Local Byelaws concerning the disposal of chemical effluent.


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CONTENTSPage No

TITLE PAGE (i). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SCOPE (iii). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FOREWORD (v). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sponsorship (v). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conditions of Release (v). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Categories of NES (vi). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Related Documents (vi). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Health and Safety (vi). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Additional Information (vii). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CONTENTS (ix). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SECTION 1. PERFORMANCE SPECIFICATION 1.1. . . . . . . . . . . . . . . . . .

1.1 Constraints 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.1 Demineralized Water 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Pre-Requisites for the Flushing, Cleaning and Inhibiting Process 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.1 Sampling Points 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.2 Temporary Flushing Rig 1.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 The Flushing, Cleaning and Inhibiting Process 1.2. . . . . . . . . . . 1.3.1 High Velocity Flush 1.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.2 Degrease/Biological Decontamination 1.2. . . . . . . . . . . . . . . . . . 1.3.3 Inhibited Acid Clean 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.4 Weak Acid Rinse 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.5 Chemical Passivation 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.6 Final Fill and Inhibition 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Witnessing and Acceptance 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.1 Nominated Witness 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.2 Acceptance Criteria 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 2. NATIONAL/INTERNATIONAL REGULATIONS 2.1. . . . . . .

SECTION 3. MILITARY STANDARDS/REQUIREMENTS 3.1. . . . . . . . . . . 3.1 Constraints 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.1 Technical Advice 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.2 Time-scales 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.3 Operational Notice 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.4 Working Hours 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.5 Integration with Other Activities 3.1. . . . . . . . . . . . . . . . . . . . . .


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3.1.6 System Temperatures 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.7 Water Quality 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.8 Demineralized Water 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Pre-Requisites for the Flushing, Cleaning and Inhibiting

Process 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.1 Site Inspections 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.2 Dockside Facilities and Services 3.2. . . . . . . . . . . . . . . . . . . . . . . 3.2.3 Two-way Radios 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.4 System Features 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.5 Draining and Venting Provisions 3.3. . . . . . . . . . . . . . . . . . . . . . 3.2.6 Sampling Points 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.7 Ships Pumps 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.8 Responsibilities 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.9 Temporary Flushing Rig 3.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.10 Connection of Temporary Flushing Rig to System 3.4. . . . . . . . 3.2.11 Flushing Velocities 3.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.12 Disposal of Effluent 3.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.13 Control of Substances Hazardous to Health Risk

Assessments 3.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.14 Method Statement 3.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3 Site Preparation for the Flushing, Cleaning and Inhibiting Process 3.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 4. DESIGN REQUIREMENTS/GUIDANCE 4.1. . . . . . . . . . . . . .

SECTION 5. CORPORATE EXPERIENCE & KNOWLEDGE 5.1. . . . . . . . 5.1 Chilled Water Systems 5.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.1 General 5.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.2 System Contaminants 5.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 Outline Procedure 5.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.1 Chemicals 5.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.2 Procedures 5.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 Requirements of the Cleaning Contractor 5.3. . . . . . . . . . . . . . . 5.3.1 Qualifications 5.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 The Flushing, Cleaning and Inhibiting Process 5.3. . . . . . . . . . . 5.4.1 High Velocity Flush 5.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.2 Degrease/Biological Decontamination 5.4. . . . . . . . . . . . . . . . . . 5.4.3 Inhibited Acid Clean 5.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.4 Weak Acid Rinse 5.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.5 Chemical Passivation 5.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.6 Final Fill and Inhibition 5.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ANNEX A. RELATED DOCUMENTS A.1. . . . . . . . . . . . . . . . . . . . . . . . . .

ANNEX B. ABBREVIATIONS AND DEFINITIONS B.1. . . . . . . . . . . . . . .

ANNEX C. PROCUREMENT CHECK LIST C.1. . . . . . . . . . . . . . . . . . . . .


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ANNEX D. MATERIALS USED IN THE CONSTRUCTION OF CHILLED WATER SYSTEMS AND THE EQUIPMENT THEY SUPPLY D.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ANNEX E. INHIBITING CHEMICALS E.1. . . . . . . . . . . . . . . . . . . . . . . . . .

ALPHABETICAL INDEX INDEX 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


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1.1

1. PERFORMANCE SPECIFICATION

Related Documents: BR 6549; see also Annex A.

1.1 Constraints

1.1.1 Demineralized Water

a. The demineralized water to be supplied for the final (and any subsequent) fillof the system must conform to the following:

(1) Conductivity


1.2

1.2.2 Temporary Flushing Rig

a. The cleaning contractor is to provide a temporary flushing rig for thecirculation of water and chemicals during the flushing procedure, and foremptying the system on completion of each stage in the process. The temporaryflushing rig should incorporate the following features:

(1) A flushing tank for the storage of flushing water;

(2) A flushing pump to circulate the water;

(3) A chemical dosing tank;

(4) An effluent storage tank (or other disposal point);

(5) A calibrated orifice plate to enable the measurement of flushing flow rates(and hence velocities);

(6) Pressure test gauges to monitor the static pressure at discharge from thepumps;

(7) A drain point from which water samples can be taken.

1.3 The Flushing, Cleaning and Inhibiting Process

1.3.1 High Velocity Flush

a. The chilled water system is to undergo a high velocity flush to remove all loosedebris. A dispersant chemical is to be added to the flushing water to encourageloose debris into suspension. The flushing water is to be pumped from thecontractors temporary flushing tank. The flush will be a oncethrough processwithout circulation of the flushing water. With the closure of isolating valvesthe chilled water system will be subdivided into sections, each of which is toreceive a full flush for 10 minutes, or until the water runs clear. At the end ofeach flush, the open section of the system should be valvedoff and the nextsection opened ready for the flush to proceed, once the flushing tank has beenrefilled. This process should continue until all parts of the system have beenflushed. For each stage of the process, the total flow rate through each part ofthe system should be recorded and demonstrated to a witness nominated by theContract Sponsor (see Clause 1.4.1). The recorded flow rates should indicatethat velocities of at least 3 m/s were achieved in the largest pipes in the system.

1.3.2 Degrease/Biological Decontamination

a. An alkaline degreasant and biocide/biofilm removal agent is to be added andcirculated for a period to be specified by the cleaning contractor. The chilledwater may be heated to a maximum temperature of 50C if required for thisprocess. Checks for adequate circulation are to be carried out by taking up tofour water samples from around the system, and measuring pH levels. Furtherchecks should be carried out by measurement of pipe temperatures in eachcircuit by means of touch thermometers. On completion, the system water isto be pumped back to the effluent storage vessel for disposal. The system is thento be refilled and vented.

b. A high velocity flush is to be carried out (see Clause 5.4.1a), in order to removethe products of the degrease/biological decontamination. On completion thesystem is then drained, refilled and vented.


1.3

1.3.3 Inhibited Acid Clean

a. An inhibited acid clean is to be carried out, as determined by the cleaningcontractor, and be suitable to remove free iron in the system without damagingthe system materials. If considered appropriate, a suitable biofilm treatmentchemical is to be circulated with the main cleaning chemical to act as a wettingagent to effectively reduce the surface tension of the water and allow theingress of porous material. The water may be heated to a temperature notexceeding 50C. In order to ensure complete circulation of the chemical, watersamples are to be taken and pipe surface temperatures measured. To allowanalysis of pH levels, water samples are to be taken from up to four samplingpoints around the system. Pipe surface temperatures are to be measured usinga touch thermometer in every subcircuit in the system. Samples are also to betaken at regular intervals from the drain point in the temporary rig. These areto be checked for dissolved iron levels. When iron levels are seen to plateau,water circulation is to be continued for a further two hours. On completion, thesystem water is to be pumped back to the effluent storage vessel for disposal.The system is then to be refilled and vented.

1.3.4 Weak Acid Rinse

a. A weak acid rinse is to be carried out in order to remove any excess chemicalcontamination from residual iron oxide. This rinse is to be circulated for aminimum period of one hour, after which the system water is to be pumped backto the effluent storage vessel for disposal. The system is then to be refilled andvented.

b. A final high velocity flush is to be carried out (see Clause 5.4.1a). The systemis then to be refilled and vented.

1.3.5 Chemical Passivation

a. Passivation process chemicals are to be added while the system remains full andcirculating. The cleaning contractor must ensure that the cleaning chemicalsused are compatible with the chemicals to be used for final inhibition of thesystem. The passivation chemicals are to be circulated for a period of between16 to 24 hours. Iron and chemical concentration levels are to be monitoredduring this period and the system is to be flushed and bled as required. Thesystem is then to be drained and refilled with demineralized water (as detailedin Clause 1.1.1) and circulated to all areas for two hours to displace or dilute alltraces of raw water.

1.3.6 Final Fill and Inhibition

a. The chilled water system is then to be emptied and refilled with demineralizedwater, with passivating/inhibiting chemicals added in sufficient quantities toachieve the water standards referred to in Clause 1.1.1b. These chemicals (asdetailed in Annex E) will be held onboard or made available from Naval stores.The chilled water system is to be left full and circulating while all Constaflovalves and strainer meshes are reinstalled by the Ships Staff (or refitcontractor). On completion, the system is to be restored to the normaloperational state and circulation restored to the ships pumps. Referenceshould be made to BR 6549.


1.4

1.4 Witnessing and Acceptance

1.4.1 Nominated Witness

a. A person nominated by the Contract Sponsor is to witness the flushing andcleaning process to confirm compliance with the cleaning contractors MethodStatement in Clause 3.2.4.

b. The nominated witness is to verify a number of measurements carried outduring the flushing and chemical cleaning process. The scope of witnessedmeasurements will be specified by the Contract Sponsor but will include thefollowing:

(1) Levels of Total Dissolved Solids (TDS) measured at each stage of the highvelocity flushing stages;

(2) Flow rate measurements at the temporary flushing rig measurementdevice at each of the high velocity flushing stages;

(3) Iron levels in the water during the acid cleaning stage;

(4) Citrate levels during the acid cleaning stage.

c. The nominated witness may also view the removal of samples at agreed pointsaround the system and the measurement of pipe surface temperatures. Theextent of witnessing these samples and temperatures is to be agreed with theContract Sponsor.

1.4.2 Acceptance Criteria

a. The acceptance criteria for the results of the witnessed measurements carriedout in Clause 1.4.1b. are that:

(1) The TDS levels achieved at the end of each high velocity flush are notgreater than 10% above the incoming mains water;

(2) The velocities during each high velocity flushing stage are in excess of3 m/s in the largest pipe in the system;

(3) Iron levels recorded during the acid cleaning stage are seen to plateau;

(4) Citrate levels are maintained within the contractors recommendedlimits;

(5) The demineralized water quality used for the final fill of the systemcomplies with Clause 1.1.1.

b. Formal acceptance of the clean depends on the receipt of a report which willdemonstrate that all test results are in compliance with the appropriateacceptance criteria. The report should contain the following information:

(1) Laboratory analysis of the system water before cleaning;

(2) A chemical cleaning report and log sheets;

(3) Test results for all water samples taken during the clean;

(4) The cleaning contractors comments and conclusions regarding thesuccess of the clean;


1.5

(5) A record of the flushing velocities recorded for each part of the systemduring each high velocity flush;

(6) Laboratory analysis of the water used in flushing;

(7) Laboratory analysis of the demineralized water used for the final fill(as evidence of compliance with the water quality standard given inClause 1.1.1);

(8) Laboratory analysis of the system water following the addition ofinhibiting chemicals.


1.6


2.1

2. NATIONAL/INTERNATIONAL REGULATIONS

This NES contains no National/International Regulations information.


2.2


3.1

3. MILITARY STANDARDS/REQUIREMENTSRelated Documents: Water Resources Act 1991, DEF STAN 0253, Form WSAF 129;see also Annex A.

3.1 Constraints3.1.1 Technical Advice

a. The chemical clean is likely to be carried out during a planned docking periodor during a refit period. In the former case, the vessel will remain operationaland the Ships Staff will be available to provide technical advice. In the lattercase, technical advice will be available from the refit contractor.

b. The cleaning contractor must identify to the Contract Sponsor hisrequirements for technical support. If requested, skilled personnel from eitherthe Ships Staff or refit contractor will be available throughout the clean,during normal working hours, to assist the contractor in the location of onboardequipment, identification of control valves, and the supply and connection ofservices. Ships Staff will not be available for the preparation or operation ofthe cleaning contractors equipment, or for the preparation of the chilled watersystem in any way other than in an advisory capacity.

3.1.2 Time-scalesa. The whole process, from the system being fully operational in its current state,

to it being fully operational having been chemically cleaned and inhibited, mustbe carried out to a timescale agreed by the Contract sponsor. If the clean isbeing conducted outside a major docking period this timescale can normallybe assumed to be 14 days, although the period may be extended for largersystems.

3.1.3 Operational Noticea. Depending on operational requirements, the cleaning contractor must be able

to restore the system to full working order within 36 hours. In the event of thisrequirement, assistance will be available from the Ships Staff (at least oneskilled and five semiskilled personnel), but the cleaning contractor must havesufficient backup staff available to achieve this timescale should it becomenecessary.

3.1.4 Working Hoursa. 24 hour working is permitted. However, technical advice from the Ships Staff

or refit contractor will not be available outside normal working hours and theavailability of some dockside supplies may be limited.

3.1.5 Integration with Other Activitiesa. The clean will be carried out during a maintenance period with many other

activities being undertaken in parallel. The chemical clean and inhibitprocesses are not to cause any obstruction to the free movement of otherpersonnel or equipment in the vessel. However, it is accepted that in terms ofavailability of chilled water and conditions of habitability, the clean may haveto take precedence over all other activities.

3.1.6 System Temperaturesa. A limiting system temperature of 50C is set for the refrigerant side of the

chilled water plant. This is to limit overpressurization of the evaporator andassociated valves and pipework.


3.2

3.1.7 Water Qualitya. The quality of water used for the flushing, degreasing and chemical cleaning of

the system is left to the discretion of the cleaning contractor. It is anticipatedthat mains supplied water will suffice although the cleaning contractor shouldensure that water hardness and conductivity levels are compatible with thecleaning method.

3.1.8 Demineralized Water

a. The demineralized water to be supplied for the final (and any subsequent) fillof the system must conform to the following:

(1) Conductivity


3.3

3.2.3 Two-way Radios

a. The cleaning contractor must obtain permission from the Contract Sponsor ifthey intend to use portable twoway radios during the cleaning process. Thispermission may be denied onboard some vessels and in some dockyard areas.

3.2.4 System Features

a. The cleaning contractor is to notify the Contract sponsor of any features of thesystem which may prevent a successful clean or suffer damage as a consequenceof the flushing and chemical cleaning process, and should therefore be removedor bypassed.

3.2.5 Draining and Venting Provisions

a. The cleaning contractor is to inform the Contract Sponsor of appropriate sizesand positions of temporary connections for draining the system completely, andenabling flushing velocities to be achieved. Previous flushing exercises haveshown that a 25 mm drain connection is adequate to allow proper drainage offlushing water and chemicals from the system. This drain connection may beon the suction side of the chilled water pumps in surface ships, and from thebase of the evaporators in submarines.

b. The cleaning contractor is to allow for the provision of temporary pumps topump out water from temporary drain points back to an appropriate effluentstorage facility.

3.2.6 Sampling Points

a. The cleaning contractor is to agree with the Contract Sponsor, the preciselocations of sampling points from which water will be taken for analysis. Thesamples will be used to establish if the cleaning chemicals are being properlycirculated and the final system quality is satisfactory.

3.2.7 Ships Pumps

a. The cleaning contractor must obtain approval from the MEO (or refitcontractor) if they intend to operate the system during the high velocityflushing stage. If approval to use the system pumps is given, the contractormust demonstrate that adequate precautions have been taken to protect thepumps from damage due to loose material circulated in the water.

3.2.8 Responsibilities

a. The cleaning contractor is to agree with the Contract Sponsor, the scope of theirjoint responsibilities in relation to preparing the system for cleaning, and howthese overlap with those of the Ships Staff or refit contractor. In particularfrom the following list, which is not exhaustive, who is responsible for:

(1) The removal of Constaflo inserts and strainer inserts;

(2) The provision of temporary drains at low points in the system;

(3) The provision of spool pieces to bypass removed sections of pipework orcomponents.


3.4

3.2.9 Temporary Flushing Rig

a. The cleaning contractor is to provide a temporary flushing rig for thecirculation of water and chemicals during the flushing procedure, and foremptying the system on completion of each stage in the process. The temporaryflushing rig should incorporate the following features:

(1) A flushing tank for the storage of flushing water;

(2) A flushing pump to circulate the water;

(3) A chemical dosing tank;

(4) An effluent storage tank (or other disposal point);

(5) A calibrated orifice plate to enable the measurement of flushing flow rates(and hence velocities);

(6) Pressure test gauges to monitor the static pressure at discharge from thepumps;

(7) A drain point from which water samples can be taken.

b. The cleaning contractor is to provide details of the size, weights and capacityof all temporary equipment such as flushing tanks and effluent storage tanks.

c. The flushing tank should be large enough to allow constant pumping for at least10 minutes before the need to refill the tank.

d. The cleaning contractor is to agree with Contract Sponsor an appropriatelocation for the positioning of the temporary flushing rig.

e. The cleaning contractor is to provide a schematic diagram of the proposedflushing rig and 1:50 scale working drawing of the proposed layout for theparticular site location.

f. The cleaning contractor is to ensure that the operating pressures in histemporary facilities do not exceed the maximum safe level for the ship s system.The rig is to incorporate static pressure test gauges on the flushing pump outletto enable pressures to be monitored.

3.2.10 Connection of Temporary Flushing Rig to System

a. The cleaning contractor is to agree with the MEO (or refit contractor) theprecise location for connection of the temporary flushing rig to the chilled watersystem. In most cases, this will be via deck mounted goose neck pipeconnections specifically provided for this purpose. The cleaning contractor isto provide appropriate couplings to allow connection to these fittings.

b. The cleaning contractor is to make adequate allowance for tidal movements inthe design of his temporary rig, and its connection to the system.

3.2.11 Flushing Velocities

a. The cleaning contractor is to establish in advance how the required flushingvelocities and cleaning temperatures are to be achieved, and demonstrated. Inparticular, the contractor is to size his temporary pumps to ensure that thevolume flow rates necessary for the flushing process can be achieved.


3.5

b. The cleaning contractor is to ensure that system pressures achieved during theflushing procedure do not exceed the maximum operating pressures for thesystem.

3.2.12 Disposal of Effluent

a. In accordance with the requirements of the Water Resources Act 1991, thecleaning contractor is to obtain approval from the local water undertaking (andany other relevant regulatory bodies) for the disposal of contaminated flushingwater, and in particular, for the disposal of cleaning chemicals. If approvalcannot be obtained, the contractor will make preparations for the removal ofwaste by other means.

3.2.13 Control of Substances Hazardous to Health Risk Assessments

a. The cleaning contractor is to provide product data sheets and, whereappropriate, Control of Substances Hazardous to Health (COSHH) riskassessments for all chemicals and procedures used as part of the cleaningprocess. Copies of COSHH risk assessments will be provided to the ContractSponsor and to Ships Staff (or refit contractors) who may be involved in thecleaning process. COSHH risk assessments should cover the substancespresent (and any other forms into which they may be transferred); whatharmful effects they may have; what harmful substances are given off in theiruse; who may be affected by them; to what extent and period of time they areat risk; and what precautions are to be implemented in the event of an accident.

3.2.14 Method Statement

a. The cleaning contractor is to provide a detailed method statement of how he willcarry out the flushing and chemical cleaning, and his anticipated programmeand timescales, to the Contract Sponsor, Ships Staff, other contractors and allthose involved in the cleaning process. The programme and timescales are tobe agreed with the Contract Sponsor.

3.3 Site Preparation for the Flushing, Cleaning and Inhibiting Process

a. The cleaning contractor:

(1) Must notify the vessels MEO, and the Contract Sponsor, of their presenceand involvement before commencing work onboard;

(2) Is to check that all Constaflo valve inserts and strainer meshes have beenremoved. When it is agreed that the removal of the inserts is to be carriedout by the cleaning contractor, each insert is to be clearly labelled with thenumber of the valve from which it was removed, and is then to be baggedand tied to the valve. Meshes and inserts will be replaced by the ShipsStaff (or refit contractor) on completion of the clean;

(3) Is to confirm with the Ships Staff (or refit contractor), that anycomponents removed for refurbishment purposes have been replaced bythe appropriate spool pieces and that the system has been pressure testedto at least 1.5 working pressure as confirmation of system integritybefore the fill for flushing purposes commences.


3.6


4.1

4. DESIGN REQUIREMENTS/GUIDANCEThis NES contains no Design Requirements/Guidance information.


4.2


5.1

5. CORPORATE EXPERIENCE & KNOWLEDGE

Related Documents: BS EN ISO 9001, BR 6549; see also Annex A.

5.1 Chilled Water Systems

5.1.1 General

a. Chilled water systems in HM Surface Ships, Submarines and RFA vessels existprimarily to provide cooling for weapon systems via either direct or indirectheat exchangers. They also provide cooling for accommodation and workingspace ventilation systems, via direct air/chilled water heat exchangers. Withoutthe chilled water system being periodically flushed and cleaned, these HMvessels will rapidly become uninhabitable with weapon systems notfunctioning.

5.1.2 System Contaminants

a. The cleaning contractor must have the necessary experience and qualificationsto flush and chemical clean chilled water systems in HM vessels that may suffercontamination from the following typical sources:

(1) Corrosion Products. Chiller shells may be manufactured from a numberof materials including mild steel. Mild steel in the presence of untreatedwater will corrode, forming iron oxides such as magnetite and rust;

(2) Installation Debris. Water systems can pick up many extraneous materialsduring manufacture, storage and installation/refurbishment. Theseinclude millscale, metal swarf, grease, oil and jointing materials;

(3) Sedimentary Deposits. These are introduced to the system during fillingfrom unsuitable water sources;

(4) Scale. Scale is a build up of solid material which normally occurs on theinternal surfaces of evaporators. Scale is a dense, adherent deposition ofmineral particles which are tightly bound to each other and to the metalsurfaces. Calcium, magnesium and iron salts are the most commonscales;

(5) Biological Fouling. Bacteria can be introduced to a system with theoriginal fill water. Left untreated, a biofilm layer can quickly develop. Inthe right conditions certain types of bacteria may multiply with suchrapidity that pipes become blocked or locked with gas. Sulphate reducingbacteria are the most destructive and can cause severe localized pittingon steel pipework surfaces.

5.2 Outline Procedure

5.2.1 Chemicals

a. The cleaning contractor is to supply all chemicals necessary to complete theflushing and chemical cleaning of the system.

b. The agent used for the chemical clean must be to a formulation based on aninhibited acid. Previous cleans using formulations containing ammoniatedcitric acid have achieved satisfactory results within the operating constraintsand timescales called for in this NES.


5.2

c. The particular chemical products used, and their concentrations, are left to thediscretion of the cleaning contractor, but they must be compatible with thecleaning procedures outlined in Clauses 5.2.2b.(1) and (2), and as furtherdescribed in Clause 3.3.

d. The chemicals used for the chemical clean must not cause any reaction with thematerials of the chilled water system, other than that required for the solepurpose of cleaning. A representative systems materials list is included inAnnex D.

e. In particular, the cleaning contractor must ensure that there is no risk of copperplating onto mild steel surfaces (this is a common problem with cleans usingacids).

f. On completion of the flush and chemical clean the system is to be dosed withcorrosion inhibitor chemicals supplied by MOD. These will either be heldonboard the vessel or will be available from Naval stores. Product data sheetsfor these chemicals are included in Annex E. Details of system dosing andtesting are given in BR 6549. The chemical injection equipment incorporatedin the system is detailed in Annex E.

5.2.2 Procedures

a. The whole system is to be cleaned. Only by exception and with prior approvalof the Warship Support Agency (WSA) may the system be cleaned in part/partsor fitted equipment excluded from the cleaning process. When the wholesystem is not to be cleaned the Contract sponsor is to define and document, incontractual terms, boundary points and specific areas of responsibility toensure that crosscontamination does not take place.

b. The extent of the chemical clean and inhibition procedure is to be advised bythe cleaning contractor based on his assessment of the system and system waterconditions. There are likely to be two types of clean:

(1) For systems constructed entirely from cupronickel pipework andcomponents (or other nonferrous materials), and for which the maincontaminant is of bacteriological origin, the chemical clean may take theform of a high velocity flush and a biocide clean. The clean must containthe following principal stages in the stated order:

(a) High velocity flush to remove loose debris;

(b) Bacteriological contamination removal;

(c) High velocity flush to remove debris created by process (b);

(d) Chemical passivation to stabilize the system;

(e) Final fill and dosage with inhibitor chemicals.

(2) For systems containing ferrous components and those which exhibit highlevels of iron contamination, the clean must include the followingprincipal stages in the stated order:

(a) High velocity flush to remove loose debris;

(b) Degrease/bacteriological contamination removal;

(c) High velocity flush to remove debris created by process (b);


5.3

(d) Inhibited acid clean/iron oxide removal;

(e) Weak acid rinse to remove any excess chemical contamination andresidual iron oxide;

(f) High velocity flush to remove debris created by process (e);

(g) Displace/dilute all traces of raw water;

(h) Chemical passivation to stabilize the system and prevent flashrusting;

(i) Final fill and dosage with inhibitor chemicals.

5.3 Requirements of the Cleaning Contractor5.3.1 Qualifications

a. The cleaning contractor:

(1) Is to carry quality assurance certification to BS EN ISO 9001 for the scopeof work described in this NES;

(2) Must be able to demonstrate that his staff have been given appropriatetraining in the processes and chemical monitoring requirementsdescribed in this NES. The MOD reserve the right to request details oftraining records for individual staff members;

(3) Is to have instant recourse to at least one person who holds a degree inchemistry or chemical engineering, and has extensive experience indealing with chilled water system cleans of HM Surface Ship, Submarineand RFA vessel size and complexity, during the cleaning process;

(4) Is to have a laboratory service capable of full chemical and bacteriologicalanalysis;

(5) Is to be capable of calculating mean flow rates and flushing velocitiesaround the system and be capable of measuring and recording these flowrates for demonstration purposes.

5.4 The Flushing, Cleaning and Inhibiting Processa. The flush and chemical clean will involve some combination of the stages

described in this Section as decided by the cleaning contractor.

5.4.1 High Velocity Flush

a. The chilled water system is to undergo a high velocity flush to remove all loosedebris. A dispersant chemical is to be added to the flushing water to encourageloose debris into suspension. The flushing water is to be pumped from thecontractors temporary flushing tank. The flush will be a oncethrough processwithout circulation of the flushing water. With the closure of isolating valvesthe chilled water system will be subdivided into sections, each of which is toreceive a full flush for 10 minutes, or until the water runs clear. At the end ofeach flush, the open section of the system should be valvedoff and the nextsection opened ready for the flush to proceed once the flushing tank has beenrefilled. This process should continue until all parts of the system have beenflushed. For each stage of the process the total flow rate through each part ofthe system should be recorded and demonstrated to a witness nominated by theContract Sponsor (see Clause 1.4.1). The recorded flow rates should indicatethat velocities of at least 3 m/s were achieved in the largest pipes in the system.


5.4

5.4.2 Degrease/Biological Decontamination

a. An alkaline degreasant and biocide/biofilm removal agent is to be added andcirculated for a period to be specified by the cleaning contractor. The chilledwater may be heated to a maximum temperature of 50C if required for thisprocess. Checks for adequate circulation are to be carried out by taking up tofour water samples from around the system, and measuring pH levels. Furtherchecks should be carried out by measurement of pipe temperatures in eachcircuit by means of touch thermometers. On completion, the system water isto be pumped back to the effluent storage vessel for disposal. The system is thento be refilled and vented.

b. A high velocity flush is to be carried out (see Clause 5.4.1a.), in order to removethe products of the degrease/biological decontamination. On completion thesystem is then drained, refilled and vented.

5.4.3 Inhibited Acid Clean

a. An inhibited acid clean is to be carried out, as determined by the cleaningcontractor, and be suitable to remove free iron in the system without damagingthe system materials. If considered appropriate, a suitable biofilm treatmentchemical is to be circulated with the main cleaning chemical to act as a wettingagent to effectively reduce the surface tension of the water and allow theingress of porous material. The water may be heated to a temperature notexceeding 50C. In order to ensure complete circulation of the chemical, watersamples are to be taken and pipe surface temperatures measured. To allowanalysis of pH levels water samples are to be taken from up to four samplingpoints around the system. Pipe surface temperatures are to be measured usinga touch thermometer in every subcircuit in the system. Samples are also to betaken at regular intervals from the drain point in the temporary rig. These areto be checked for dissolved iron levels. When iron levels are seen to plateau,water circulation is to be continued for a further two hours. On completion, thesystem water is to be pumped back to the effluent storage vessel for disposal.The system is then to be refilled and vented.

5.4.4 Weak Acid Rinse

a. A weak acid rinse is to be carried out in order to remove any excess chemicalcontamination from residual iron oxide. This rinse is to be circulated for aminimum period of one hour, after which the system water is to be pumped backto the effluent storage vessel for disposal. The system is then to be refilled andvented.

b. A final high velocity flush is to be carried out (see Clause 5.4.1a.). The systemis then to be refilled and vented.

5.4.5 Chemical Passivation

a. Passivation process chemicals are to be added while the system remains full andcirculating. The cleaning contractor must ensure that the cleaning chemicalsused are compatible with the chemicals to be used for final inhibition of thesystem. The passivation chemicals are to be circulated for a period of between16 to 24 hours. Iron and chemical concentration levels are to be monitoredduring this period and the system is to be flushed and bled as required. Thesystem is then to be drained and refilled with demineralized water (as detailedin Clause 1.1.1) and circulated to all areas for two hours to displace or dilute alltraces of raw water.


5.5

5.4.6 Final Fill and Inhibition

a. The chilled water system is then to be emptied and refilled with demineralizedwater, with passivating/inhibiting chemicals added in sufficient quantities toachieve the water standards referred to in Clause 1.1.1b. These chemicals (asdetailed in Annex E) will be held onboard or made available from Naval stores.The chilled water system is to be left full and circulating while all Constaflovalves and strainer meshes are reinstalled by the Ships Staff (or refitcontractor). On completion, the system is to be restored to the normaloperational state and circulation restored to the ships pumps. Referenceshould be made to BR 6549.


5.6


ANNEX AA.1

ANNEX A.

RELATED DOCUMENTS

A1. The following documents and publications are referred to in this NES:

HMSO The Water Resources Act 1991

HMSO Health and Safety at Work etc. Act 1974

SI 437 Control of Substances Hazardous to Health Regulations (COSHH)

SI 2051 Management of Health and Safety at Work Regulations

SI 2306 Provision and use of Work Equipment Regulations

SI 3140 Construction (Design and Management) Regulations

BS 1400 Specification for Copper Alloy Ingots and Copper Alloy and HighConductivity Copper Castings

BS EN 1SO 9001 Quality Systems. Model for Quality Assurance in Design,Development, Production, Installation and Servicing

JSP 430 Ships Safety Management System HandbookVolume 1: Policy and Guidance on MOD Ship Equipment Safety Management

DEF STAN 02-53 Guide to the Completion of Form WSAF 129 Shore SupportRequirements for Warships

BR 6549 Corrosion Inhibited Chilled Water System Standard

A2. Additional information describing the specific details of Chilled Water Systems in Type 22Frigates, Type 42 Destroyers and CVS is included in the following documents:

Type 22 Frigates

BRF 6613(506) Batch Two Chilled Water System

BRF 6613(507) Batch Three Chilled Water System

Type 42 Frigates

BRF 6611(510) Batch One and Two Chilled Water System

BRF 6611(509) HMS Manchester Chilled Water System

BRF 6611(508) Batch Three Chilled Water System

SDN42M524000125

Chilled Water System

CVS

BRF 6615(502) Invincible Class Chilled Water System

SDN 004421530 Schematic Arrangement of CWS OMS

SDN 004421610 Arrangement CWS OMS

SDN 004421554 Arrangement CWS FGR

SDN 004423684 Compartment Arrangement Fwd ACP Room

SDN 004423688 Compartment Arrangement Aft ACP Room


ANNEX A A.2

CVS (Continued)SDN 006001733 Schematic Diagram of Chilled Water Essential Services Valve

Groups

A3. Further advice may be obtained from Building Services Research and Information Association(BSRIA), and in particular their Application Guide AG8/91 Precommission Cleaning ofWater Systems.


ANNEX BB.1

ANNEX B.

ABBREVIATIONS AND DEFINITIONS

B1. For the purpose of this NES the following abbreviations apply:

BR Book of Reference

BS British Standard

BSRIA Building Services Research and Information Association

CFU Colony Forming Units

COSHH Control of Substances Hazardous to Health

DEF STAN Defence Standard

DLO Defence Logistics Organization

DPA Defence Procurement Agency

ICS Integrated Communications System

JSP Joint Services Publication

MEO Mechanical Engineering Officer

NES Naval Engineering Standard

PSU Power Supply Unit

PTFE Polytetrafluoroethylene

RFA Royal Fleet Auxiliary

RN Royal Navy

SI Statutory Instruction

SSA Ships Support Agency

TDS Total Dissolved Solids

B2. For the purpose of the NES the following definitions apply:

Biocide A chemical agent which either kills or prevents themultiplication of biological organisms in water systems.

Constaflo Trade name for constant flow regulating device commonlyinstalled on chilled water subcircuits in RN vessels.

Contract Sponsor The party responsible for initiating the cleaning contract.

Dispersants Substances which create a repellent force betweenindividual particles, thereby encouraging them to remain insuspension during flushing.

Inhibitor Any compound that suppresses corrosion. The terminhibitor applies to two distinctly different chemicals,commonly in use. Acid inhibitors control the action of anacid solution used for cleaning; corrosion inhibitors controlthe further corrosion of metal surfaces in water.

Magnetite A ferric oxide formed when steel pipes or componentscorrode. Magnetite appears as a fine black magnetic powder.

Millscale A surface layer of mainly ferric oxides formed during themanufacture of mild steel.


ANNEX B B.2

Passivator A compound that renders the active surface of thepipework passive, i.e. less prone to further corrosion.Every passivator is an inhibitor.

Quality The totality of features and characteristics of a product orservice that bear on its ability to satisfy stated or impliedneeds.

Quality Assurance All those planned and systematic actions necessary toprovide adequate confidence that a product or service willsatisfy given requirements for quality.

Rust Hydrated ferric oxide formed when steel pipes orcomponents corrode. Rust appears as a reddish brown flakypowder.

Safety Freedom from unacceptable risk of harm.

Ships Staff The RN allocated to crew a specific ship, submarine or RFAvessel.

System The chilled water system undergoing the flushing andchemical cleaning process.


ANNEX CC.1

ANNEX C.

PROCUREMENT CHECK LIST

C1. No relevant information included.


ANNEX C C.2


ANNEX DD.1

ANNEX D.

MATERIALS USED IN THE CONSTRUCTION OF CHILLED WATER SYSTEMS ANDTHE EQUIPMENT THEY SUPPLYD.1 The materials listed in this Annex are used in the construction of chilled water

systems in RN vessels and the equipment they supply. Although the lists are headedType 22, Type 42 and CVSG, it can be assumed that all these vessels will use the samematerials somewhere in their systems.

D.2 Materials List for Type 42 Class and CVSG:

Pipes: 90/10 Coppernickel

Valves/fittings: Gun metal, rubber, aluminiumbrass

Joints: Rubberized cork, hard fibre

Bolts/nuts/washers: Aluminiumbronze

Flanges: Gun metal

Bosses: Brazing metal (nonferrous)

ACUs: Copper

ATUs: Copper

Plants/pumps: Mild Steel

Weapons:

Jammer Outfits670/675(2):

Rubber flexihose (PTFE), copper piping, mild steelheat exchanger*

* Secondary system of675(2)

Heat exchanger contains special PVC bag

Mk. 8 Gun: Designed to take sea water

SCOT: 90/10 Coppernickel, LG2 bronze to BS 1400, silversolder (55% silver), nylon and gland packing joints,PTFE

Hydraulic Oil Cooker:(909 Annex)

Aluminiumbrass, leaded gun metal, brass, stainlesssteel, aluminiumbronze, copper, neoprene

Sonar 2016: Neoprene rubber, brass, copper, phosphorbronze

Sonar 2050:

Water to water heat exchanger:

Copper, silver braze

Joints: Tin internal and external

Water connections: in BSP Yorkshire imperial (copper)

Water flow switch: Magnet and in BSP Yorkshire imperial (copper)

Regulator fluid pressure:

Gun metal, silicon rubber, acetal copolymer

Selfsealing coupling:

Stainless Steel S130, nitrile rubber

Sonar 996:

Heat exchanger Gun metal, naval brass (electrotinned),Cupronickeliron (CN102), solder (Grade F), nitrileviton


ANNEX D D.2

Air/water heat exchanger:

Aluminiumbrass, naval brass, silver solder, copperconnections

300 V PSU: Aluminiumbrass tube

Coolant pump: Stainless steel, phosphorbronze

Flow switch: Stainless steel

Pipes and fittings: Stainless steel, aluminiumbrass

Flexihose: PTFE inner lining

Constaflo: Stainless steel, gun metal, silicon rubber, viton,nylon, PTFE 66

High power isolator:

Austenitic stainless steel, phosphorbronze, PTFE,Indox (magnetic material)

Heat exchanger: Copper, brass, aluminium brass, brazing (silver,copper eutectic)

D.3 Materials List for Type 22 Frigates:

Chillers: Steel

Valves: Gun metal, stainless steel, aluminium bronze

Pipes: Copper or coppernickel

Fittings: Coppernickel, gun metal, stainless steel, rubber,plastic, red fibre (washers), rubber/cork (joint rings),aluminiumsiliconbronze

Weapons:

Hose assembly: Elastomeric rubber compound (type AQP), stainlesssteel braid with anodized alloy couplings

Heat exchanger: Stainless steel

SCOT 1A: 90/10 Coppernickel, LG2 bronze to BS 1400, silversolder (55% to BS 1854), nylon and gland packingjoints, PTFE

ICS 2A/3 (Outfits TDD,CVQ and FSD):

Copper and aluminiumbronze

4.5 Mk 8 Gun: Designed to take sea and fresh water

Goalkeeper: Copper, stainless steel


ANNEX EE.1

ANNEX E.

INHIBITING CHEMICALS

E.1 Supplies of the following chemicals are held on board the vessel or are available fromNaval Stores. They are to be used on completion of the clean to achieve the requiredwater quality standards given in Clause 3.1.8:

a. Cooltreat 651 (50 litres) (see Pages E2 to E3 for Product Data Sheet PD 952,and Pages E4 to E7 for Safety Data Sheet SDS 952);

b. Microtreat 2200 (25 litres) (see Pages E8 to E9 for Product Data Sheet PD 153).

E.2 The chemical injection equipment held on board consists of:

a. HB 42 or E+LPD3 pump set;

b. Stainless Steel quill fitting;

c. Nonreturn Valve for quill.

E.3 The chemicals listed above are introduced into the chilled water system via the quillinjection fitting, which is located in the main system riser.


ANNEX E E.2


ANNEX EE.3


ANNEX E E.4


ANNEX EE.5


ANNEX E E.6


ANNEX EE.7


ANNEX E E.8


ANNEX EE.9


ANNEX E E.10


INDEXINDEX 1

ALPHABETICAL INDEXNote: Page numbers are given

AAcceptance Criteria: 1.4

CChemical Passivation: 1.3, 5.4

Chemicals: 5.1

Chilled Water Systems: 5.1

Cleaning, Flushing and Inhibiting Process:1.2

Connection of Temporary Flushing Rig toSystem: 3.4

Constraints: 1.1, 3.1

COSHH Risk Assessments: 3.5

DDegrease/Biological Decontamination: 1.2,

5.4

Demineralized Water: 1.1, 3.2

Disposal of Effluent: 3.5

Dockside Facilities and Services: 3.2

Draining and Venting Provisions: 3.3

FFinal Fill and Inhibition: 1.3, 5.5

Flushing Velocities: 3.4

GGeneral: 5.1

HHigh Velocity Flush: 1.2

IInhibited Acid Clean: 1.3, 5.4

Integration with other Activities: 3.1

MMethod Statement: 3.5

NNominated Witness: 1.4

OOperational Notice: 3.1

Outline Procedure: 5.1

PPre-Requisites for the Flushing, Cleaning

and Inhibiting Process: 1.1

Procedures: 5.2

QQualifications: 5.3

RRequirements of the Cleaning Contractor:

5.3

Responsibilities: 3.3

SSampling Points: 1.1, 3.3

Ships Pumps: 3.3

Site Inspections: 3.2

Site Preparation: 3.5

System Contaminants: 5.1

System Features: 3.3

System Temperatures: 3.1


INDEX INDEX 2

TTechnical Advice: 3.1

Temporary Flushing Rig: 1.2

Temporary Flushing Rigs: 3.4

Timescales: 3.1

Two Way Radios: 3.3

WWater Quality: 3.2

Weak Acid Rinse: 1.3, 5.4

Witnessing and Acceptance: 1.4

Working Hours: 3.1

Inside Rear Cover

Crown Copyright 2001

Copying Only as Agreed with Dstan

Defence Standards are Published by and Obtainable from:

Defence Procurement AgencyAn Executive Agency of The Ministry of Defence

Directorate of StandardizationKentigern House65 Brown Street

GLASGOW G2 8EX

DStan Helpdesk

Tel 0141 224 2531/2 Fax 0141 224 2503

Internet e-mail [email protected]

File Reference

The DStan file reference relating to work on this standard is D/DStan/069/02/387.

Contract Requirements

When Defence Standards are incorporated into contracts users are responsible for their correctapplication and for complying with contractual and statutory requirements. Compliance witha Defence Standard does not in itself confer immunity from legal obligations.

Revision of Defence Standards

Defence Standards are revised as necessary by up issue or amendment. It is important thatusers of Defence Standards should ascertain that they are in possession of the latest issue oramendment. Information on all Defence Standards is contained in Def Stan 00-00 Standardsfor Defence Part 3 , Index of Standards for Defence Procurement Section 4 Index of DefenceStandards and Defence Specifications published annually and supplemented regularly byStandards in Defence News (SID News). Any person who, when making use of a DefenceStandard encounters an inaccuracy or ambiguity is requested to notify the Directorate ofStandardization (DStan) without delay in order that the matter may be investigated andappropriate action taken.

CONTENTSNOTICE: PLEASE READTITLE PAGESCOPEFOREWORDSponsorshipConditions of ReleaseCategories of NESRelated DocumentsHealth and SafetyAdditional InformationNational Legislation

1. PERFORMANCE SPECIFICATION1.1 Constraints1.1.1 Demineralized Water

1.2 Pre-Requisites for the Flushing, Cleaning and Inhibiting Process1.2.1 Sampling Points1.2.2 Temporary Flushing Rig

1.3 The Flushing, Cleaning and Inhibiting Process1.3.1 High Velocity Flush1.3.2 Degrease/Biological Decontamination1.3.3 Inhibited Acid Clean1.3.4 Weak Acid Rinse1.3.5 Chemical Passivation1.3.6 Final Fill and Inhibition

1.4 Witnessing and Acceptance1.4.1 Nominated Witness1.4.2 Acceptance Criteria

2. NATIONAL/INTERNATIONAL REGULATIONS3. MILITARY STANDARDS/REQUIREMENTS3.1 Constraints3.1.1 Technical Advice3.1.2 Time-scales3.1.3 Operational Notice3.1.4 Working Hours3.1.5 Integration with Other Activities3.1.6 System Temperatures3.1.7 Water Quality3.1.8 Demineralized Water

3.2 Pre-Requisites for the Flushing, Cleaning and Inhibiting Process3.2.1 Site Inspections3.2.2 Dockside Facilities and Services3.2.3 Two-way Radios3.2.4 System Features3.2.5 Draining and Venting Provisions3.2.6 Sampling Points3.2.7 Ships Pumps3.2.8 Responsibilities3.2.9 Temporary Flushing Rig3.2.10 Connection of Temporary Flushing Rig to System3.2.11 Flushing Velocities3.2.12 Disposal of Effluent3.2.13 Control of Substances Hazardous to Health Risk Assessments3.2.14 Method Statement

3.3 Site Preparation for the Flushing, Cleaning and Inhibiting Process

4. DESIGN REQUIREMENTS/GUIDANCE5. CORPORATE EXPERIENCE & KNOWLEDGE5.1 Chilled Water Systems5.1.1 General5.1.2 System Contaminants

5.2 Outline Procedure5.2.1 Chemicals5.2.2 Procedures

5.3 Requirements of the Cleaning Contractor5.3.1 Qualifications

5.4 The Flushing, Cleaning and Inhibiting Process5.4.1 High Velocity Flush5.4.2 Degrease/Biological Decontamination5.4.3 Inhibited Acid Clean5.4.4 Weak Acid Rinse5.4.5 Chemical Passivation5.4.6 Final Fill and Inhibition

ANNEX A. RELATED DOCUMENTSANNEX B. ABBREVIATIONS AND DEFINITIONSANNEX C. PROCUREMENT CHECK LISTANNEX D. MATERIALS USED IN THE CONSTRUCTION OF CHILLED WATER SYSTEMS AND THE EQUIPMENT THEY SUPPLYANNEX E. INHIBITING CHEMICALSALPHABETICAL INDEX

NES 387 Chemical Cleaning of Chilled Water System Category 2

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Transcript of NES 387 Chemical Cleaning of Chilled Water System Category 2