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INSPECTION PLAN FOR LARGE STORAGE TANKS

PROJECT NAME: NACIMIENTO

Type 600-CSSN-02

Design code: Inner vessel: AD-2000 with supplementPiping: Directive 97/23/EC, EN 13480

Drawing Nos. 600081014 Tank assembly600081076 Inner vessel6000 Outer vessel6000 Inner vessel weld plan

Abbreviations:

IO Inspection Organisation (According to contract)SC Sub ContractorNC Non destructive testing company (Accredied by authoritys)CT CRYO AB design departmentCTW CRYO AB welding department.

IVD =Inner Vessel Drawing.OVD =Outer Vessel Drawing.ICL =Inspection Check List.IVWP =Inner Vessel Weld Plan.

Performance of inspection activities:

P= To be performedW= To be witnessedR= To be reviewed

CRYO AB

INSPECTION PLANLARGE STORAGE TANKS

Design Date

CTA-J C 05-10-12

Drawing No. Issue Page

600081124 0 1(7)



SPECIFICATION SUPPORTING DOCUMENTATION PERFORMANCEDOCUMENT CT IO

CTWSC

1 PRODUCTION DOCUMENT

1.1 Design, drawings Design code according Drawings, specifications. P --specifications. to IVD.

1.2 Design approval. Design code according Approval and stamping P --to IVD. of drawings.

1.3 Welding procedure. Welding procedure speci- Procedure qualification. P --fication acc. to IVD. Record./Welding drw.

1.4 Welders qualification. IVD / Welding drw. Qualification records P --acc to EN 287-1

Note. 1.3 and 1.4 Procedure qualification and welders qualification records performed by the Sub Contractor

CRYO AB

INSPECTION PLAN

LARGE STORAGE TANKS

Design Date

CTA-J C 05-10-12


600081124 0 2(7)



SPECIFICATION SUPPORTING DOCUMENTATION PERFORMANCEDOCUMENT SC NC IO

2 MANUFACTURING AND TESTING OF THE INNER VESSEL

BOTTOM 2.1 Visual inspection of plate IVD, Weld drawing ICL P -- --edges before welding

2.2 Material identification of IVD, ICL. ICL P -- --bottom plates

2.3 Visual inspection of the IVD, Weld drawing, ICL ICL P -- --complete welds.Completion of weld nos.

2.4 Dimension check (bottom) IVD, ICL ICL P -- --

2.5 Radiographic examination of IVD, IVWP ICL, Record -- P --butt welds Range: 200 mm on each

weld against the shell radius.

2.6 Vacuum test of butt welds IVD ICL, Record -- P --Range: All butt welds

Vacuum level : -500mBar

2.7 Liquid penetrant exam. of fillet IVD, ICL ICL,Record -- P --welds between shell/bottom Range:100 %

SHELL

2.8 Visual inspection of plate IVD, Weld drawing ICL P -- --edges before welding

2.9 Material identification of IVD, ICL. ICL P -- --shell plates

2.10 Visual inspection of the IVD, Weld drawing, ICL ICL P -- --complete welds, includingstiffening rings.Completion of weld nos.

2.11 Radiographic examination of IVD, IVWP ICL, Record -- P --butt welds Range: LW / CW: 100%

2.12 Liquid penetrant exam. of fillet IVD, ICL ICL, Record -- P --welds between shell/ Range:100 %compression ring

2.13 Liquid penetrant test of IVD, ICL ICL, Record -- P --bolt supports Range:100 %

CRYO AB


Design Date

CTA-J C 05-10-12 Drawing No. Issue Page

600081124 0 3(7)





ROOF 2.14 Visual inspection of plate IVD, Weld drawing ICL P -- --edges before welding

2.15 Material identification of IVD, ICL. ICL P -- --roof plates

2.16 Visual inspection of the IVD, Weld drawing, ICL ICL P -- --complete welds.Completion of weld nos.

2.17 Radiographic examination of IVD, IVWP ICL, Record -- P --butt welds (roof/comp.ring Range: 100% center plate)

2.18 Liquid penetrant exam. of IVD ICL,Record -- P --fillet welds (roof/comp.ring Range: 100% center plate and manway)

PIPING IN INSULATION SPACE TO THE FIRST SHUT OF VALVE

2.19 Visual inspection of pipe/ IVD, Weld drawing ICL P -- --flange edges before welding

2.20 Material identification of IVD, ICL. ICL P -- --pipes/flanges

2.21 Visual inspection of the IVD, Weld drawing, ICL ICL P -- --

complete welds on piping.Completion of weld nos.

2.22 Radiographic examination of IVD ICL, Record -- P --butt welds Range: 100 %

2.23 Liquid penetrant exam. of IVD ICL, Record -- P --branch welds Range: 100 %

COMPLETE TANK

2.24 Cleaning of roof/shell/bottom Drawing 600020964 ICL, Record P -- --

2.25 Internal inspection before IVD ICL P -- --

pressure test

2.26 Dimension check IVD, ICL ICL, Record P -- --complete vessel Drawing: 600016161

2.27 Reviewing of documentation IVD,ICL, NDT-Reports, ICL P P --materialcertificates

CRYO AB


Design Date

CTA-J C 05-10-12


600081124 0 4(7)





2.28 Filling of water, hydraulic test IVD, Pressure test certificate. PΣ -- -water evacuation Test pressure 0.286 bar(g) Stamping of ICL

Drawing: 600073255 and name plate.

2.29 Control of settlement IVD ICL, Record P -- --

2.30 Drying of inner vessel and IVD ICL, Record P -- --piping Drawing 600021471

2.31 Leak test of manhole (roof) Soap water ICL P --Pressure 0.2 Bar

2.32 Check of relief valves IVD, Manufacturers P -- -- Test-Certificate, ICL

CRYO AB


Design Date

CTA-J C 05-10-12


600081124 0 5(7)




3 MANUFACTURING AND TESTING OF THE OUTER VESSEL

SHELL

3.1 Visual inspection of plate OVD ICL P -- --edges before welding

3.2 Visual inspection of the OVD, ICL ICL P -- --complete welds, includingstiffening rings.

3.3 Radiographic examination of OVD, ICL. ICL, Record -- P --

butt welds. AD HP 5/3 DIN 54 111 or similar.Range: 1 film (spot check)

ROOF

3.4 Visual inspection of plate OVD ICL P -- --edges before welding

3.5 Visual inspection of the OVD, ICL ICL P -- --complete welds.

3.6 Radiographic examination of OVD, ICL. ICL, Record -- P --

butt welds. AD HP 5/3 DIN 54 111 or similarRange: 1 film (spot check)

CRYO AB

INSPECTION PLAN

LARGE STORAGE TANKS

Design Date

CTA-J C 05-10-12


600081124 0 6(7)




COMPLETE TANK

3.7 Reviewing of documentation OVD,ICL, NDT-Reports, ICL P P --

3.8 Check of relief valves OVD, Manufacturers -- -- -- Test-Certificate

4 DOCUMENTATION

4.1 Review of documentation Contract, ICL, NDT-Reports ------------------ PΣ --dossier

Σ Together with CRYO AB

NOTES:

1) Radiographic testing of welds shall be performed in accordance with EN 1435.

2) Liquid penetrant testing of welds shall be performed in accordance with EN 571-1.

(Acceptance level 2 according to EN 1289 tabel 1),

3) The weld quality shall be in accordance with quality level B/EN 25817 (acceptance level 1 according to EN 12517) for the inner vessel,piping. The outer vessel shall be in accordance with quality level C/EN 25817 (acceptance level 2 according to EN 12517).

4) Pressure test of pipes shall be done with nitrogen or oil-free air.

CRYO AB

INSPECTION PLAN

LARGE STORAGE TANKS

Design Date

CTA-J C 05-10-12


600081124 0 7(7)



DRYING SPECIFICATIONFLAT BOTTOM STORAGE TANKS ANDPIPING FOR CRYOGENIC SERVICE

AGA-CRYO AB

Sweden

Type of document

GENERAL

Date

1995-10-30

Des.

ÅE

Appr. Page

1 (4)

Doc.No. Rev.

E600021471-0WORD/RITN/JBH13439.DOC/YL

1. SCOPE

This specification specifies the procedures for drying and the requirements of drynessof the interior of inner vessel and piping for cryogenic service.Part A describes the procedure for inner vessel with piping to the first valve.Part B describes the procedure for piping between cryogenic storage tank andcoldbox, pumps, vaporizers, truckfilling equipment etc.

2. GENERAL

Drying is applied to prevent, male function of valves and equipment and blockagesof piping, due to ice formation at cooling down with cryogenic liquid.Drying is accomplished by blowing through hot gas (convection), the necessaryenergy for water vaporization is transported to the goods by the hot gas itself.

The gas temperature should be in the range of 70-150 °C for hot gas drying.Large volumes of gas is needed for this operation, the higher temperature thesmaller gas volume is needed, but temperature must not be so high that sealingmaterial etc is damaged.

3. REQUIREMENTS

Drying shall continue until the gas leaving the dried space has reached a dewpoint of - 40°C, or lower.




AGA-CRYO AB

Sweden

Type of document

GENERAL

Date

1995-10-30

Des.

ÅE

Appr. Page

2 (4)

Doc.No. Rev.


A. DRYING OF INNER VESSEL AND PIPING TO FIRST VALVE

A.1 DrainingPrior to commencing drying all remaining water must be emptied.Special care must be taken to all horisontal surfaces and where deadends and other pockets exist. See cleanliness spec. 600020964, part B6.

A.2 Drying The drying is effected by blowing through dry (dew point < -50 °C), hot nitrogen(or clean oilfree air). It is important to check that all parts are reached by the hotgas.

The drying continues until the gas leaving the inner vessel has reached a dewpoint of - 40 °C, or lower.Note: If water is frozen before start of drying a dewpoint of - 40°C can be reached

fast .But the ice is still there. This means that the drying time must be longer when there is risk for ice.

A.3 Preservation of drynessAfter drying the inner vessel is pressurized to 0.1 barg, with dry nitrogen untilcooling down.

A.4 Documentation

Always write a record of the drying procedure, (date, time, dewpoint).See example in Annex, page 4.




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Type of document

GENERAL

Date

1995-10-30

Des.

ÅE

Appr. Page

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Doc.No. Rev.


B. DRYING OF PIPING

B.1 Draining and clean blowingPrior to commencing drying all remaining water must be emptied.Special care must be taken where dead ends and other pockets exist.See cleanliness spec. 600020964 part C11.

B.2 Drying The drying is effected by blowing through dry (dew point < - 50 °C), hotnitrogen. It is important to check that all parts are reached by the hot gas.

The drying continues until the gas leaving the dried pipe system has reacheda dew point of - 40 °C, or lower.Note: If water is frozen before start of drying a dewpoint of - 40 °C can bereached fast. But the ice is still there.

This means that the drying time must be longer when there is risk for ice.

B.3 Preservation of drynessAfter drying the piping is pressurized to 0,5 barg with dry nitrogen until coolingdown.

B.4 Documentation

Always write a record of the drying procedure, (date, time, dewpoint).See example in Annex, page 4.




AGA-CRYO AB

Sweden

Type of document

GENERAL

Date

1995-10-30

Des.

ÅE

Appr. Page

4 (4)

Doc.No. Rev.


RECORD OF DRYING Customer:

Contractor:

Contract:

Project:

ITEM DRIED

Description: _______________________________________________________________

Identity: ___________________________________________________________________ Drying specification No 600021471

Drying Gas: Dew point: Temperature

Ambient temperature:

Start of drying: Date: Time:

Drying accomplished Date: Time:

Achieved Dewpoint:

Item sealed and pressurized by nitrogen at: bar Time:

Contractor Inspector Name: Name: Name:

Date: Date: Date:Sign: Sign: Sign:



CLEANLINESS SPECIFICATION

FLAT BOTTOM STORAGE TANKS

AND PIPING FOR OXYGEN SERVICE

AGA-CRYO AB

Sweden Type of document

SPECIFICATION

Date

1996-09-25

Des.

ÅE

Appr. Page

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Doc.No. Rev.

600020964-0

1. SCOPE

This specification specifies the minimum requirements on the cleanliness of all surfaces of cryogenic storage tanks, piping and components, which are in contact with cryogenic orgaseous oxygen at any expected operating condition.

2. PURPOSE

The purpose of this specification is to define the acceptable level of surface and particlecontamination to minimize the risk for malfunction of equipment and to ensure safetyagainst ignition when in contact with oxygen.

3. NORMATIVE REFERENCES

This specification is based on prEN 12300:1996.Normative references are citated at the appropriate places in the text and the publicationsare listed hereafter.

prEN 1797-1 Gas/Material Compatibility - Part 1: Oxygen compatibility

prEN 12300 Cryogenic vessels - Cleanliness for cryogenic service

4. REQUIREMENTS

The surface concerned shall have a sufficiently low level of contamination to avoid:

- hydrocarbon or particle reaction with oxygen- corrosion- malfunction of the equipment due to for example to ice or particle blockage.

No hydrocarbon contamination, paint, adhesives, sealants and protective coating, except if oxygen compatible in accordance with prEN 1797-1 shall be detectable by visual inspection

using bright white light;

- the maximum acceptable hydrocarbon contamination (oil, grease, etc) is 500 mg/m2,but not concentrated on partial areas.

No chips, foreign matter, major potentialy loose particles such as oxide scale, weldspatter, are acceptable;

- no visible particles under white light are acceptable (without magnification)- no free water shall be detectable






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600020964-0

5. CLEANING PROCEDURE

Any cleaning procedure may be used, providing the requirements of 4 are met. Chosenmust as a procedure minimum fullfill local legislation for health, safety and environment,and also local regulations for disposal of waste must be followed.If solvent or other cleaning agents are used, it shall be ensured that they are adequately removed.

Particular care shall be taken to remove any non oxygen compatibel agents(see prEN 1797-1).

In Annex. B and C examples are given of cleaning procedures for inner vessel and piping.

6. CLEANLINESS ASSESSMENT

The cleanliness inspection method and its frequency shall be chosen to ensure con-formity with the requirements of 4. The method and its frequency shall take into accountthe cleaning method, the equipment and its expected level of contamination.

Any method of inspection shall not itself result in contamination levels specified in 4.

Cleanliness assessment methods may include the methods listed in Annex A. Thecleanliness assessment methods shall be documented and results recorded.

In Annex D. example is given of a record of inspection.

7. POST CLEANING PROTECTION

After cleaning items shall be protected to maintain the clean condition until used. Con-sideration shall be given to purging and sealing equipment to reduce the risk of condensingany atmospheric moisture during storage.

Any packaging, plugs, etc. in contact with the clean surfaces shall be clean and re-movable without leaving any residue. Any packaging material should be strong, able tobe sealed and waterproof.






AGA-CRYO AB


SPECIFICATION

Date

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Des.

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Annex A (informative)

Inspection Methods

Various methods exist for determining the cleanliness acceptance of equipment and it is necessarythat the selected method complements the cleaning method used. This Annex covers the mostpractical and effective methods available. It is necessary that qualified inspectors with the necessary

training and relevant industrial experience are used for this activity.

All parts being checked by solvent flushing or immersion shall be able to drain freely to emptythe solvent. If an area is identified which cannot freely drain, a method must be developed tocompletely remove the solvent without leaving an area of contamination.

For parts that are inaccessible for inspection after assembly, it may be necessary to disassem-ble or inspect parts prior to assembly. Consideration shall be given to any contamination which mayoccur during to assembly of inspected components.

If an inspection reveals the presence of any contaminants, the item shall be partially or eventotally recleaned. Persistent rejection requires a re-evaluation of the manufactures cleaning methods and

quality control provisions before re-acceptance as a satisfactory supplier.

A.1 Direct Visual Inspection Method with Daylight or Art if ic ial White Light

This is the most common inspection method used to detect the presence of contaminants on equip-ment with easily accessible surfaces. This method will without magnification detect very smallparticles and moisture, oils, grease, etc. in relatively small amounts.

The effectiveness of this method is dependent on the roughness of the inspected surface. The ISOStandard 2632 N9, Rugotest No 3 can be used as a minimum reference condition for sandblastedor mechanically cleaned steel surfaces.

Magnifying glasses are not necessary, but it is important to have a sufficient bright level or daylightor artificial white light.

Visual inspection of the surfaces allows examinations for:

- moisture (free water)- cleaning agents- flux residues from brazing, soldering or welding- rust and loose scale, weld spatters, particles, fibres or other foreign matter- organic material such as oils, grease, paint, etc. Hydrocarbon contamination levels of 500 mg/m2 can be detected by this method.






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A.2 Direct Visual Inspection Method with Ul traviolet Light

Ultraviolet light causes many common, but not all hydrocarbon or organic oils to fluorescene.An ultraviolet light with a wavalenght of about 370 mm is used in dark or near darkness at adistance of about 10 to 20 cm from the surface or piece being examined. This method mightindicate fluorescent areas to be further inspected by other means such as wipe test, etc.Fluorescent traces due to material residues know to be harmless are acceptable.

It is important not to rely alone on the result of this test to consider a piece of equipmentcleaned for use in oxygen service as some vegetable oils do not fluorescene under ultra-violet light, therefore although this test can be useful it is certainly not the most importantinspection method and should be suppported by white light and/or wipe tests.

Note that excessive exposure to direct or reflected ultraviolet light can cause eye and skindamage and therefore care must be taken when it is being used and lamp manufacturersinstructions shall be complied with.

A.3 Wipe Test Method

This test is useful when white light inspection has been inconclusive.

The surface is rubbed lightly with a clean lint-free cotton or linen cloth or with a white filter paper.

This cloth or paper is examined under white light and/or UV light to find any contaminating traces.A light oxide discoloration is in some cases acceptable. Since it is not acceptable to leave paperor cloth particles on the equipment, this method is not recommended for rough or cast materials.

A.4 Water Break Test

This test may be used to detect oily residues not found by other means. The surface is wetted witha spray of clean water. This should form a thin layer and remain unbroken for at least five seconds.Beading of the water droplets indicates the presence of oil contaminants.

A.5 Solvent Contamination Test Method

This inspection method is used to check the result of highly specialised methods of solvent cleaningwhen inaccessible surfaces or bigger installations have to be cleaned. For most small componentsit is easier and more economical to disassemble for inspection or to inspect before assembly. Itshould be taken into consideration, that this method of cleaning and inspection is limited by theability to reach and dissolve the contaminants if present.

Local contamination in pockets of complex equipment may be detected using this method of inspection by getting successive slight but constant indications of contamination. Considerable

experience is necessary to assess the results of this method.






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The method of inspection is based on the comparison of used and unused solvent. The level of,or freedom from contamination present during solvent cleaning can be closely followed by takingsuccessive solvent samples during the entire cleaning process until inspection confirms that theacceptance standard is reached. Checking the amount of contaminants in a used sample is agood indication of the cleanliness level reached.

The amount of contaminants in a sample can be determined in three ways:

- weight of residue (laboratory test)- volume of residue (laboratory test)- light transmission

A.5.1 Weight o f Residue

A known quantity (MS) of a representative sample of unfiltered used solvent is contained in asmall weighed beaker and is evaporated to dryness, being careful not to overheat the residueand the weight (m2) of the residue established. In the same manner, the weight (m1) of residuefrom a similar quantity of clean unused solvent is determined. The difference in weight betweenthe two residues and the quantity of representative sample used is related to the total quantity (MV)of solvent used and is used to compute the amount of residual contaminant removed per square

meter (mc) of surface area A, cleaned.

mc = (m2 - m1) Mv / Ms

Am1 = weight of residue (clean solvent)m2 = weight of residue (used solvent)Ms = weight of representative sample (used solvent)Mv = totalt weight of solvent usedA = surface area of component cleanedm3 = weight of contamination present per area cleaned

A.5.2 Volume of Residue

A measured quantity of a sample of the unfiltered used solvent can be placed in a clear glasscontainment and evaporated to dryness. The volume of residue can be measured directly andused to compute the volume of contaminant extracted per square meter of surface aread cleaned.Greater sensitivity can be achieved by successive evaporation of quantities of the same extractedsolvent batch in the same glass containment.

A.5.3 Light Transmission

A sample of the unfiltered used solvent is compared to a reference sample of unused solvent bycomparing light transmission through the two samples simultaneously. The difference in colour

or light absorption and in particle content of the solvents are a qualitative indication of the amountof contaminants dissolved. The quantity of any contaminants in a sample can be estimated byanalysis technics, e.g making use of UV or infrared light.

Annex B.(Informative)






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SPECIFICATION

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600020964-0

Detergent cleaning of an inner vessel for a flat bottom tank, with high pressure cleaningequipment

B.1 Initial Inspection

Before start of welding, all plates and components are to be visual inspected for hydrocarboncontamination (oil, grease, paint, etc.).If contamination are detected the material must be cleaned before welding.

B.2 Mechanical Cleaning

After welding interior surfaces shall be mechanically cleaned, (scraping, wire-brushing etc)to remove welding spatter, sparks, slag etc.

B.3 Dedusting

Internal surfaces shall be swept and vacuum cleaned.

B.4 Cleaning

Cleaning agent:

Water based alkaline detergent. A foaming agent is to prefer because of its ability to stick to verticalsurfaces. Several suitable cleaners are available on the market.

Cleaning conditions like detergent concetration, rinsing water temperature etc. should be settledthrough tests and should comply with the manufacturer s product information and material safetydata sheets, which must be carefully studied and followed.

Cleaning method:

The cleaning is done section by section starting from the top of the inner vessel.Cleaning agent is applied by spraying at low pressure and ambient temperature. The cleaner foammust wet the whole internal surface.

The cleaner foam is left on the surface for a time, according to the detergent suppliers recommendation,for dirt dissolving action.

The surface is rinsed by high pressure clean water, until all residue is flushed away.At the end, the bottom is cleaned, rinsed and the water is removed, the last by rubber wiper,swabbing and wiping with lintfree cloth.






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B.5 Inspection

After a section is cleaned and rinsed and the water is dried off, the whole surface of the sectionis to be inspected by method A1. Direct visual inspection with white light, in combination withmethod A3. Wipe test, on several spots of the section and on all areas where suspectedcontaminations are detected by inspection with method A1.If the requirements of section 4 of this specification are not met, the whole section must becleaned once more.

B.6 Hydrostatic Test and Final Inspection

Clear potable uncontaminated water shall be used for hydrostatic test. (Make water-analysis).During lowering the water level, after the hydrostatic test, a final inspection of the cleanlinesscan be made from a rubberboat, using method A1 in combination with method A3.Method A3. to be carried out on all horizontal surfaces. If particles (sand etc.), is detected theyare to be wiped off and if some hydrocarbonic contamination is detected they are to be swabbedoff using detergent and the area is then flushed with water.At the end the remaining water on the bottom is pumped away and the bottom is swabbedand wiped dry before the final cleanliness inspection. The connecting piping, up to the first valve, that has tanken part in the hydrostatic testing, is to

be drained from all remaining water.

B.7 Drying and Preservation

The inner vessel and connecting piping are dried according to drying specification No: 600021471Afterwards it is slightly pressurized with dry nitrogen until cooling down.

B.8 Documentation

Records are made of all inspections and acceptances for the cleaned equipment. The record willinclude:

a) Identification of the item coveredb) Cleanliness specificatinsc) Cleaning method employedd) Method of inspectione) Results of inspectionf) Inspector s signature and date






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Annex C (Informative)

Cleaning of Stainless Steel Piping

C.1 Scope

This annex deals with the piping between cryogenic storage tanks and coldbox, pumps, vaporizers,

truckfilling equipment etc.It is made of stainless steel but also soldered brass connectors are used.

C.2 Pre-Cleaning

All pipe lenghts, fittings and components to be purchased with internal surfaces pre-cleaned foroxygen service according to this specification, with documented cleanliness inspection accordingto A1 and A3, with all openings sealed with caps and waterproof masking tape immediately aftercleaning, and labelled "Cleaned for oxygen service".As alternative all parts can be purchased uncleaned and be cleaned according to C5-C8 + C14before start of fabrication.

C.3 Initial Inspection

Before start of welding all pipes and parts are to be inspected, to check, documentation and labelingfor oxygen service and unbroken sealings etc. Parts that does not fullfill cleanliness requirementshas to be cleaned according to C5-C8 before start of welding.

C.4 Pre-Fabrication

Piping is prefabricated in sections suitable for cleaning, with as few field welds as possible to be doneafter cleaning.Exercise care in order to maintain cleanliness throughout fabrication and testing, preferable TIGshall be used for welding. Welds should be inspected as work progresses and any weld repairsexecuted.Pipe ends must be sealed at all times except when fabrication is actually taking place. A gas backpurge should be maintained during welding.If the cleanliness has been maintained during pre-fabrication, cleaning according to C5 can be replaceby cleanblowing according to C11.

C.5 Cleaning

Equipment:

A high pressure cleaning equipment with high pressure flexible hose and pipe cleaning nozzles.

The backward directed jets from the nozzle pull the hose into and through the pipe while flushingthe internal surface.

Cleaning agent:






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Water based alkaline detergent. A foaming agent is to prefer because of its ability to stick to verticalsurfaces. Several suitable cleaners are available on the market.

Cleaning conditions like detergent concentration, rinsing water temperature etc. should be settledthrough tests and should comply with the manufacturer s product information and material safetydata sheets which must be carefully studied and followed.

Cleaning method:

The cleaning agent is applied at low pressure and ambient temperature via the hose and the nozzle.In this sequence, the hose must be transported through the pipe manually. The cleaner foam must wet the whole internal surface. The cleaner foam is left 5-10 minutes insidethe pipe for dirt dissolving action. During this time period, the pipe should be rotated/turned around2-3 times to ensure good cleaner accessibility.

Rinsing:

The internal of the pipe is rinsed by high pressure clean water form the pipe cleaning nozzle. The hose is slowly transported forward and back so all internal surfaces are hit by the flushing

water. The rinsing is continued until the pH value of outcoming rinsing water is the same asthat of fresh ingoing water. (pH value may be tested by litmus reactive paper).In some cases, the cleaning/rinsing procedure may be repeated from other pipe openings.

Drying:

Prior to commencing drying, all free standing water must be emptied from the pipe.Special care must be taken where dead ends and other pockets exist. The drying is effected by blowing through hot nitrogen or clean oil-free air. It isimportant to check that all parts are reached by the hot gas. Drying continous until thegas leaving the piping section has reached a dew point of - 40ºC.

C.6 Cleanliness Inspection

Directly after drying, the inside surface of the piping is inspected by method A.1. Direct visual inspectionwith White Light, in combination with method A3. Wipe test in all pipe openings.A cloth fastened to a stick may be used for wipe test of deeper internal surfaces.Use lint free cloth or paper.

C.7 Conservations of Cleanliness

All pipe ends are sealed with plastic plugs, directly after inspection.

C.8 Labeling

Cleaned for oxygen service.






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C.9 Final Fabrication

Take great care in order to maintain the cleanliness throughout subsequent fabrications and testing.Only TIG with gas back purge shall be used for field welds. Welds should be inspected as workprogresses and any weld repairs executed.Pipe ends must be sealed at all times except when fabrication is actualy taking place.

C.10 Pressure Testing

See pressure testing specification No 600021531.

C. 11 Clean blowing

The pipe system is blown clean from dust and water by nitrogen.Following procedure is performed to create a shock effect that really blows out all loose contaminationfrom the pipe system:A blind made of paper is placed over one outlet opening in the system and is fixed by adesive tapethe pressure in the system is then increased until the blind blows away.

Take care not exceeding max. allowed pressure in the system.

C.12 Drying

See drying specification No 600021471.

C.13 Preservation of Piping Cleanliness

After clean blowing and drying the piping is to be sealed and slightly pressurized with dry nitrogen untilcooling down.

C.14 Documentation

Records are made of all inspections and acceptances for the cleaned equipment. The record willinclude:

a) Identification of the item coveredb) Cleanliness specificationsc) Cleaning method employedd) Method of inspectione) Results of inspectionf) Inspector s signature and date






AGA-CRYO AB

Sweden Type of document Date Des. Appr. Page Doc.No. Rev.

ANNEX D (example)

RECORD OF CLEANLINESS ASSESSMENT

Customer:

Contractor:

Contract:

Project:

ITEM CLEANED

Description: _________________________________________________________________ Identity:____________________________________________________________________

_

Cleanliness specification No 600020964

Cleaning method/procedure: ____________________________________________________ ___________________________________________________________________________

Cleaning agent:

Method of inspection:

Cleanliness assessment fullfil requirements

in specification No.600020964:

Post cleaning protection:

Item labelled: Cleaned for oxygen service:

Contractor Inspector

Name: Name: Name:Date: Date: Date:Sign: Sign: Sign:

inspection plan

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