QP071

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BREDERO PIPELINE SERVICES LIMITED

CLIENT: SHELL PETROLEUM DEVELOPMENT COMPANY LTD Doc. Ref.: QP071

PROJECT: TBA Revision: 00

QUALITY PROCEDURE Rev. Date: 12th April 13

THREE LAYER COATING – SURFACE PREPARATION Page # 1 of 3

Clause Description Revision

Number in Revision column denotes change over previous issue using current revision number

1 SCOPE

1.1This document describes the procedure to be followed during surface preparation ofpipes for three layer polyethylene coating. Adherence to this procedure by the relevantpersonnel is mandatory.

2 REFERENCES

2.1 DEP 31.40.30.31-GEN February 2011

2.2 ISO 8501-1

2.3 ISO 8503-1, -2, -3 and -4

2.4 ISO 21809-1 : 2009

3 RESPONSIBILITIES

3.1Project Manager is responsible for the provision of personnel, equipment and resourcesnecessary for the full and correct execution of this procedure.

3.2 Yard Superintendent is responsible for ensuring that all personnel observe therequirements of this procedure. This responsibility is normally delegated to the

Production Supervisors under his immediate charge.

3.3

Quality Manager is responsible for ensuring that the quality requirements of thisprocedure are met at all times. This responsibility is normally delegated to the QCInspectors under his charge. Quality Manager is also responsible for raising non-

conformance reports (NCRs) where discrepancies are noted and for ensuring that anyidentified corrective actions arising from such NCRs are carried out fully and completely.

3.4

Materials Controller is responsible for the call-off, storage and issue of raw materialsrequired during execution of the project, and for the establishment and maintenance of amaterials control system such that raw materials usage is accurately recorded and anynecessary stock rotation requirements are met.

4 PROCESS DESCRIPTION

4.1 PIPE RECEIPT

4.1.1

Pipes will be placed on the incoming rack and, if fitted, bevel protectors or end caps willbe removed. Pipe identification will be made at this stage in accordance with theprovisions of procedure QP001. Foam end plugs will be fitted to prevent abrasivecollecting in the bore and the pipe external surface will be examined. Any oil or greasecontamination will be removed using a suitable non-toxic solvent. Each pipe is thenlowered onto the helical conveyor.

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4.2 PREHEATING AND BLAST CLEANING

4.2.1

The conveyor takes the pipe through a diesel-fired pre-heater and then a two-wheelcentrifugal up-blast abrasive cleaning machine. This process raises the steeltemperature above the local dew point, dries any water that may be present on theexternal surface and creates the required surface cleanliness and blast profile.

4.3 POST CLEANING INSPECTION AND HANDLING

4.3.1 After blast cleaning, pipes are kicked off the blasting conveyor and onto the blow-outstation. The foam plugs are removed and a high volume stream of air is passed throughthe bore of the pipe to remove dust and any residue of blasting abrasive.

4.3.2

The pipe is then moved onto the inspection station. As the pipe rotates on this station, afull visual inspection of the bevel ends and external surface is made. Any defects in thesteel which may affect subsequent coating operations will be noted. If the defects aresuch that the pipe cannot be further processed or requires significant remedial work, anon-conformance report (NCR) will be raised and the pipe removed from the plant bymeans of the reject conveyor. Such pipes will be quarantined pending further inspection.Minor defects which can be rectified inline will be removed by light grinding with apneumatic or electric grinder.

4.3.3 After inspection, accepted pipes are moved off the inspection station. Couplings areinstalled in the leading end of each pipe, and the pipe is lowered onto the coatingconveyor. Pipes must be coated not more than four hours after blast cleaning.

5 QUALITY REQUIREMENTS

5.1 PIPE IDENTIFICATION AND PRE-BLAST VISUAL INSPECTION

Check every pipe. Pipe unique identification will be checked against manifest(s) orpacking list(s) provided. Visual inspection for contamination and damage.

Acceptance Criteria: Pipe uniquely identified against manifest(s) or delivery note(s). Nooil or grease contamination present. No damage outside agreed limits.

5.2 ENVIRONMENTAL CONDITIONS IN BLASTING AREA

Check at the start of each morning and afternoon production shift, or where production iscontinuous not less than once every five hours, using a digital thermo-hygrometer orwhirling hygrometer and calculator disk. Record ambient temperature, relative humidityand dew point.

Acceptance Criteria: Relative humidity in the blasting area may not exceed 85%.

5.3 BLAST MEDIUM TESTING

Once per shift a sample of abrasive from the blast cleaner will be taken from the workingmix and tested in the laboratory in accordance with the requirements of procedureQP074.

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5.4 PIPE SURFACE CLEANLINESS

Visual inspection of every pipe against ISO 8503-2. Check all pipes and record twice pershift.

Acceptance Criteria: Abrasive blast surface cleanliness Sa2.5 or maximum allowabledust level shall be class 1.

5.5 PIPE SURFACE PROFILE

Check first five production pipes and thereafter once per 20 pipes against ISO 8503-2.

Acceptance Criteria: Surface profile within the range 40 to 100 microns.

5.6 CHLORIDE CONTAMINATION

Check first 5 production pipes of each morning and afternoon shift, or where productionis continuous not less than 1 per 100 pipes. Check will be made using an SCM400automated test apparatus.

Acceptance Criteria: Chloride level not greater than 20 milligrams per square metre

5.7 SURFACE TEMPERATURE PRIOR TO INDUCTION HEATING

Continuous monitoring (not less than once every hour) and record first production pipe

and thereafter one pipe in 20 using a contact pyrometer.

Acceptance Criteria: Surface temperature between 40 and 85 deg. C., and not lessthan 3 deg. C above the dew point.

5.8 TIME FROM BLAST CLEANING TO COATING

Monitor throughout production. In the event of plant stoppage for any reason, the time ofstoppage will be noted as will the time of restart. Any pipes which remain blast cleanedbut uncoated for more than four hours must be removed from the plant and re-blastedagain before coating.

Acceptance Criteria: All pipes must be coated not more than fours hours after blast

cleaning.

6 DOCUMENTATION

The following documents will be completed at the end of each shift as required:

QF007 – Blast Cleaning Inspection Report

QF008 – PE Daily Audit Round Report

RF002 – Non-conformance Report

Documents

QP071