Jpsinha II

7/27/2019 Jpsinha II

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Rehabilitation Coatings inIOCL



COATINGS USED IN WRPL

1. COAL TAR ENAMEL COATING (CTE)

2. COAL TAR BASED TAPE COATING (Hot tape)

Above two coatings stopped using for field

application due to environmental issues

3. FUSION BONDED EPOXY (FBE)

4. 3LAYER POLY-ETHYLENE COATING (3LPE)

Above coatings are suitable for plant coating only.

5. COLD TAPE COATING (Poly Ethylene)6. POLY URETHENE (PU)

Above coatings are presently being used for field

applications

7. LIQUID EPOXY COATING- Under trial run for bulk use



DESIRED PROPERTIES OF COATINGS

EASE OF APPLICATION

GOOD ADHESION TO PIPE GOOD IMPACT RESISTANCE

FLEXIBILITY

RESISTANCE TO SOIL STRESS

RESISTANCE TO FLOW (CREEP)

GOOD ELECTRICAL RESISTANCE

CHEMICAL STABILITY

RESISTANCE TO SOIL BACTERIA

RESISTANCE TO MARINE ORGANISMS

RESISTANCE TO CATHODIC DISBONDMENT

WATER PROOF

PERTOLEUM RESISTANCE

ECONOMICAL



Cold Tape Coating



Ultrasonic gauge

Surface Profile Gauge

SA 2 ½ films

Coat meter for measurement of primer thickness/Coating thickness

Holiday Detector

Adhesion Tester

Thermometer

Mirror

Instruments required at site



EXC V TION



Requirements of sand blasting

Inspect surface the pipe for pitting/ any defects

Check compressor, requirement – 7kg/sq.cm, 5.6 to 7

Cubic m/min, swing 15m

Abrasive size 1mm ( max), nozzle angle 30 deg.

Cleaning of pipe:

Inspect surface after blasting ( Ref SA 2 ½ visual

standard of SIS05 5900 “ Pictorial surface prep….Steel surface”.

surface profile:

50-75microns

Sand Blasting-cleaning of pipe



SA 2 ½ film-Before cleaning of pipe



SA 2 ½ film-After cleaning of pipe



Inner two layer+Outer

two layer

Outer-Inner

Pipe

Butyl rubber

Butyl rubber

PE

3ply/2ply Cold tape



COLD TAPE COATING APPLICATION

Primer:

Primer is a mix, of butyl rubber, syntheticcompound and solvent confirming to DIN-30672

Primer coat thickness shall be as per requirement.

(25 microns DFT) Before application of coating, primer shall be

touch dry on pipe.

Coating should be applied within the time

specified by the supplier after application of primer.

Excessive delay in application of tape willnecessitate application of fog coat of primer

before applying tape



Cold Tape – Application

Mastic putty.

Mastic putty is used to get the smooth surfaceat girth welds, sleeves and also at acceptable

defects. It is compatible for primer and tape for

getting bonding

3 ply / 2 ply PE tape.

1st layer ( 3 ply) consists of PE film sandwitched between butyl rubber films on bothside.

2nd layer (2 ply) or top ply PE film with butylrubber on the inner side

1st layer to be wrapped at a predefined tensionmachine with 50% overlap on primed surface.

2nd layer shall be over lap 50% on 1st inner tape



Cold tape pplication of Coating









Cold pplied Tape Peel testing



Cold pplied Tape Peel testing



( )



Polyurethane coating (PU)

Primer based/non-primer based PU100% Solids solvent free, two component,

High Build Polyurethane Coating.Blasting media: Copper slag, steel grit

Surface cleaning: Per SSPC SP-10 SA 2 ½

Surface Profile shall be 75-100 Microns



IMPORTANT PU SPECIFICATIONS

SL Properties Value required

1 Primer Shelf life 6 months minimum

2 Drying time at 25 Deg’ C Touch dry: 30 minutes

maximum.

3 Adhesion to steel (ASTM D 4541) >1500 PSI

4 Dry film thickness by one run 1250microns

5 Hard cure time 4 hours maximum

6 Tensile strength >12 N/sq.mm

7 Hardness shore D (ASTM D 2240) 65 shore D min

8 Impact resistance (ASTM G-14) More than 23 Nm



Blast cleaning pipe with copper slag

S f P fil M t ith P O Fil



Surface Profile Measurement with Press-O-Film



I t t ti f th fil ith S G



Interpretation of the film with Screw Gauge



Priming

Record Dew Point ,Substrate Temperature

Ensure the Substrate Temperature is at least 3

Deg C over the dew Point

Surface shall be free from loose dirt beforePriming

Mix Resin, Activator in 4.6:1 ratio by Volume

Wet Film Thickness 50 Microns

Theoretical Consumption 50 ml/ Sqr Mtr

Priming application



Priming application

P i li ti



Primer application



Primed Surface Curing till Touch Dry

Power Heating shall be done to Heat the Resin till 45

deg C

Ensure Substrate Temperature at least 3 deg Cabove Dew Point

Demarking on the Pipe for every Meter length

Tracking of the Volume of the Material Per Meter application shall be done by Numeric Counter on the

Coating Unit

Coating Application

PU i li i



PU coating application

Spraying with Tip Size 313



Spraying with Tip Size 313

PU C d



PU Coated pipe

Coating thickness measurement



Coating thickness measurement

Hardness Test



Hardness Test

Adhesion Test



Adhesion Test

Holiday Identification








General Defects in



General Defects in

Operating Pipelines

CORROSION DEFECTSInternal & External

MECHANICAL DEFECTSThird party

damage

Dents

Gouges

Cracks

Wrinkles/buckles

Arc burns

Mill anomalies

Laminations

Ovality

Blisters

Accepted pipeline repair methods



Accepted pipeline repair methods

Weld metal deposition- Not in regular practice in

IOCL Sleeves: for non leaking defects

Epoxy sleeve- no direct welding on pipe

Direct welding sleeve Composite sleeve- Non metallic compound

Mechanical clamps- for leaking defects

Pipe replacement Hot tapping- No pipe line shutdown

Open cut – Line shutdown required

Corrosion leak at Ch 3 3km ofVC



Corrosion leak at Ch 3.3km of VC

C k f ti i D t t 6 l k i SMPL d t



Crack formation in Dent at 6 o clock in SMPL due to

wooden skid at botom of pipe

Crack in pipeline due to Dent



Crack in pipeline due to Dent



PROCEDURE FOR LEAK

CLAMP INSTALLATION

Pipelines repair-By Leak clamp



Pipelines repair By Leak clamp

Basically accepted for all type of pipe repairs.

Recommended for repairing corrosion &

pilferage leaks, isolated pitting.

As a temporary repair in case of emergency

Design pressure of clamp should be more

than pipe being repaired

Not recommended where defects are

circumferentially oriented

Before installation of leak clamp neoprene

seal should be checked for its elasticity



DECIDING TYPE OF SLEEVE

Steps: Calculate ERFIf ERF =/> 0.95 or defect depth =/>80% wall thickness

prefer B type sleeve

1) If ERF < 0.95 or defect depth <80% wall thickness

analyze the defect through defect sentencing curves(defect length X axis & ratio of defect depth/WT on Yaxis

2) If the point falls in

Failure zone- B type sleeve

Repair zone-A type sleeve

Reassessment zone- A type sleeve/left with out repairas per site condition



History:SMPL pipe line is 28” Crude pipeline, constructed in 1978

Grade of pipe:API5LX52.

Defect & Observation:

Laminations- on one pipe only through out the

length and minor seepage of crude oil from laminations at

two/three locations observed during coatingrefurbishment. No further leakage of oil from pipe. No

cracks observed during inspection

Remedial action taken: Provided Continuous sleeve

Case Study of Pipe defect repair



Repair of pipeline defects-

By Hot Tapping Technique



Hot Tapping

Making a hole on pipeline for the purpose of jointing a section with an

operating pipe line at operating pressurewithout shut down of operating line.



Where Hot Tapping is required ?

1.Replacement of a section.

2.Rerouting of line3.Take off a new line from existing

line.

4.Hook up a line with another line



Advantages of Hot tapping

1. Avoid thruput loss.

2. Saving of money.

3. Avoid retrieval & transportation of bulk

quantity of product.

4. Safe operation, no spillage of product5. Environmental friendly.

6. Fast operation.



Hot tapping flash presentation link

Safety measures in Pipeline



Safety measures in Pipeline

maintenance Recommendations

◦ EIC / Site engineer to ensure trench is prepared as per tender specification and site requirement.

◦ Adherence to safety guidelines shall be certified by Site

Engineer / EIC and supervisor by generation of checklist

type format.◦ Display boards to be displayed showing trenching design

and danger of working in trench.

◦ PPEs to be worn by all the labours. This to be ensisted

by Site Engineer / EIC◦ Provision of shuttering for trench more than 2.0 m

◦ All works to start with TOOL BOX TALK

◦ Surprise checks to be carried out by Senior executives

Format for checks during trenching works



Format for checks during trenching worksS.No. Activity Status

01. Clearance given by EIC to start excavation at the site

02. Tool Box Talk given to all Contractor labour and supervisor

03. Lift tools to be used at site viz., crane, sling are tested and testing certificate(s)

checked and available at site

04. The Crane operator is holding valid driving licence and more than 21 years of age

(10.9.1.3 GCC)

06. Register of wage-cum-Muster Roll for the workmen opened at site

07. Proof regarding qualification of the supervisor checked.

08. Workmen’s Compensation Insurance

09. Safety helmet provided to all worker for safety of personnel working

10 First Aid Box with medicines placed at site

11. Drinking water available

12. Trench beyond 1.5 meter up to 3.0 meter (6.1.5 OISD-GDN-192)

Safe angle of repose 45 degree and 0.5 meter width and every 1.5 meter depth

Beyond 3.0 meter

Required shuttering and scaffolding provided

13. Barricade at 1 M height (with red and white band, self glowing caution board) for excavation beyond 1.5 meter (6.1.10 OISD-GDN-192)

14. Arrangement for entry into and exit from the trench.

15. Trench more than 4’ to have one ladder for more than 100’.

Ladder shall be extended from the bottom of the trench to at least3’3” above the

surface of the ground.( 10.5.2.0 GCC)

16 Excavation (10.5.2.0 GCC)

Excavated material shall not be placed within 5’ of the edge of the trench or half of the trench deep which ever is more

Mainline emergency Equipment



Mainline emergency Equipment

Equipment required for Mainline emergencies:

Generators, Compressors, Welding machine,

Dewatering pump, Pneumatic pump, Cold cutting

machine, Fire extinguishers etc are kept at

stations/ base stations.

These are mobilised to the repair site on

requirement basis during any emergency.

In case of non availability, the equipment are to

be taken on hire basis.

Maintenance of M/L equipment system



Maintenance of M/L equipment system

All the equipment should be run trouble free during

maintenance of any mainline work.

Trial run should be taken for all equipment for 15

minutes on monthly basis and monitor the condition of

each equipment and details should be noted.

Any defect noticed during trial run should be rectified

immediately with proper maintenance

The record of the trial run, defects observed and

maintenance carried out if any should be maintained as

per the format.



Discussion session



Thank you

Documents

Jpsinha II