TABLE 6C - REQUIRED ANALYSIS PROCEDURE
7 MANUFACTURING REQUIREMENTS
For the purpose of this Standard, the following section and subsection of standard ISO 13628-2 have been modified as written hereafter. Additional clauses to standard ISO 13628-2 are also found hereafter.
7.1 Quality Assurance
7.1.3 Process Control
All main steps in the manufacturing process shall be subject to inspection. The manufacturer’s quality plan shall specify inspection points, inspection methods and acceptance criteria. Results of all inspections shall be recorded. The manufacturer shall record every non-conformance verified during manufacture of the pipe. Process control shall be performed as a minimum for the following manufacturing processes as applicable:
a) to d) remain unchanged.
Note: When the process control is performed through the measurement of the layer characteristics in intervals, as per items 7.2.2.2 and 7.4.2.2, then they may be increased provided that manufacturer has statistics demonstrating that the process is controlled.
7.2 Carcass
7.2.2 Inspection and Acceptance Criteria
7.2.2.2 The external diameter and ovalization shall be measured and the interlock checked at the start of the production run. Subsequent of this, these parameters shall be controlled (measured and checked) at least each 10 m or as agreed with the purchaser. All results shall
N-2409 REV. A ENGLISH MAY / 2003 7.3 Polymer Extrusions
7.3.2 Inspection and Acceptance Criteria
7.3.2.2 Thickness and diameter of the internal pressure sheath and the outer sheath shall be continuously measured (i.e. at least 1 measurement per second). Manufacturer shall record process statistical data at intervals, agreed with purchaser, throughout the extrusion process.
Thickness shall be measured at the bottom, at the top and at both sides of the layer cross section. For the other extruded layers thickness and diameter measurements shall be recorded every 10 m (32.8 ft) for the first 50 m (164 ft), at these cross section positions;
subsequently, the thickness and diameter shall be measured and recorded at intervals verified by the manufacturer to be acceptable. Measurements shall be taken after the cooling process.
7.4 Pressure and Tensile Armour Layers
7.4.2 Inspection and Acceptance Criteria
7.4.2.2 The external diameter, ovalization (in case of pressure armour), and pitch (in case of tensile armours) shall be measured and recorded at least every 10 m (32.8 ft) or at intervals mutually agreed. As an additional verification of the pre-forming process, the fishscaling and clearances between 2 adjacent strips/wires shall also be checked. The interference or gap between 2 adjacent layers (pressure armour and internal pressure sheath), as foreseen in the pipe design conception, shall be controlled. The results shall be within the tolerances as specified in item 7.8.
7.4.2.2.1 For the purpose of compliance with item 5.3.2.7.4, no radial gap is allowed between the tensile armours or between the tensile armour and the adjacent layers (including the holding bandage). The absence of gap shall be indirectly controlled during the process running.
7.5 Anti-Wear, Holding Bandage, and Insulation Layers
7.5.1 General
The manufacturer shall ensure that anti-wear layers, the holding bandage, taped layers used as manufacturing aids, and insulation layers are applied in accordance with documented procedures. The procedures shall include requirements for control and monitoring of the tape application, the applied tension (in case of the holding bandage), the pitch, and the overlap of the strip, and shall document acceptance criteria for flaws. The measurements of relevant parameters for process control shall be recorded.
N-2409 REV. A ENGLISH MAY / 2003 7.6 End Fittings
7.6.2 Assembly
7.6.2.3 Control features shall be established and documented to ensure that any overheating of epoxy resin or polymer layers is prevented during welding and assembling operations. Also, if required, in the end fitting assembly procedure, that the tensile armour wires need to be bent back, this bending process shall be controlled and documented. The wire bending radius shall not be less than that one adopted for qualifying the wire or the pipe, including the fatigue criteria of the design methodology.
7.6.3 Inspection and Acceptance Criteria
7.6.3.3 The manufacturer shall use a qualified and documented procedure to verify that sufficient epoxy resin has been injected into the end fittings so that no voids are left in the end fittings which would affect their functional performance.The volume injected shall be checked by measuring the mass of injected epoxy. For the end fitting assembling on board, checking of the voids by means of x-ray or gamma-ray is not allowed, unless previous and mutually agreed and if authorized by laws and regulations and by the installation contractor.
7.6.6 Gas Relief Valves
7.6.6.1 Calibration
7.6.6.1.1 Each valve shall be calibrated and its crack and reseat pressures shall be checked in 6 readings (i.e. 6 cycles of valve opening/closing). Valve inlet is to be subjected to pressurized air. Cycles of valve opening/closing shall be performed at a pressurization/depressurization rate of 0.05 MPa/sec. The end of a cycle is defined as the time when no bubbles are noted (i.e. valve closing is assured). Crack and reseat pressures are measured at the end of each of the 6 cycles. Test criteria is the following:
a) for the 6 cycles, the specified crack pressure (Pc) is kept in the range Pc ± 0.05 MPa;
b) minimum allowable reseat pressure (Pr) = 2/3(Pc).
7.6.6.1.2 The manufacturer shall provide purchaser a certificate of calibration of each valve which content shall include the value of the measurements carried out, the series number and type of the valve, identify the instruments used in the measurements, their uncertainties, and their traceability with standard instruments.
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7.7 Special Processes 7.7.1 Welding
7.7.1.1 Qualification
7.7.1.1.1 All welding operations shall be performed by qualified welders in accordance with the manufacturers approved procedures. WPSs, WPQRs and welder qualifications shall be documented and shall be available for review by the purchaser. Welding procedure qualification shall be witnessed and approved and records of welder qualification shall be reviewed by IVA agent who is qualified to witness and approve the standards and criteria (being) used. For welding performed with automated processes or for welds that serve only as manufacturing aids, IVA witness of welder qualifications may be substituted by an ASNT qualified Level II inspector. Welders and welding procedures shall be qualified according to standards API Std 1104, ASME Section IX, EN 288-3 or equivalent. Procedures shall include acceptance/rejection criteria.
7.7.3 Coating
7.7.3.1 Anti-corrosion properties of the coating shall be adequate to protect end fittings in severe marine corrosive environments, during storage (see item 5.4.2.2) and service, upper and below the seawater surface or in the sea bottom, for the specified maximum water depth (considering the product under mud at the bottom), without any extra cathodic protection.
However, if mutually agreed, for ancillary components and accessories, cathodic protection can be used. Anti-corrosion coatings applied to end fitting parts, ancillary components, and accessories shall be resistant against severe abrasion and impacts that typically occur during pipe handling and installation. Coatings applied to these items, to limit corrosion due to internal, external, or annulus environments, shall comply with the purchaser specification, if any, and the manufacturer’s documented procedures which shall include acceptance criteria.
Otherwise, the coatings shall comply with the manufacturer’s documented procedures.
7.7.3.2 The qualification procedure for application of the metallic coating onto the end fittings, ancillary components, and accessories, shall specify the following as a minimum:
a) bath composition;
b) control of temperature, time and atmosphere for heat treatments;
c) hardness test of coating (if electroless nickel coating is specified, the hardness test is not required);
d) adhesion test of coating (as per standards ASTM B733 and ASTM B571) after heat treatment, and subsequent verification of lamination through bending test of a coated specimen;
e) optical microscopy or a similar method recommended to analyze the cross section of the coated surface, in order to check minimum thickness of the interdiffusion between the base material and the metallic coating, if applicable;
f) coating thickness measurement;
g) testing to check the coating against flaws and porosity when it is subjected to the following corrosion agents: SO2 (preferable), salt spray or CO2;
h) procedures for checking the following:
- demagnetization of pieces before coating, whenever necessary;
N-2409 REV. A ENGLISH MAY / 2003 - before coating, through dye penetrant test, 100 % of the surface of pieces
against porosity, cracks, indentation, inclusion, and pits;
- after coating, inspection for flaws and porosity [for cathodic coating, through the use of potassium ferro-cyanide K4Fe (CN6)];
i) chemical composition of the coating;
j) verification of the adequacy of the geometrical complexity and dimensions of the specimen used for qualification purpose of the coating in comparison with the component/accessory.
7.7.3.3 For the supply of products with metallic coating, the manufacturer’s written procedure shall comply, at least, with the following requirements, unless otherwise mutually agreed:
a) bath composition;
b) control of temperature, time and atmosphere for heat treatments;
c) hardness test of coating (if electroless nickel coating is specified, the hardness test is not required);
d) adhesion test of coating (as per standards ASTM B733 and ASTM B571) after heat treatment, and subsequent verification of lamination through bending test of a coated specimen;
e) optical microscopy or a similar method recommended to analyze the cross section of the coated surface, in order to check minimum thickness of the interdiffusion between the base material and the metallic coating, if applicable;
f) coating thickness measurement;
g) procedures for checking the following:
- demagnetization of pieces before coating, whenever necessary;
- before coating, through dye penetrant test, 100 % of the surface of pieces against porosity, cracks, indentation, inclusion, and pits;
- after coating, inspection for flaws and porosity [for cathodic coating, through the use of potassium ferro-cyanide K4Fe (CN6)];
h) for each bath (coating process and heat treatment) manufacturer shall perform the control of the process through coupons, properly traceable to the history of the component/accessory to be delivered;
i) coupons shall be used for checking coating chemical composition (after each immersion bath and before heat treatments), thickness (before heat treatment), porosity and flaws (after coating and heat treatment), bending characteristics (after heat treatment), residual stresses before heat treatment (stresses shall be compressive or neutral), and thickness of the interdiffusion of the coating, if specified, after heat treatment.
7.8 Manufacturing Tolerances
7.8.1 The manufacturer shall document the tolerances to be used for each layer of the flexible pipe. These tolerances shall be verified in the design process to be acceptable, in that the functional requirements of the individual layers and pipe are unaffected by variations within the specified tolerances. As a minimum, tolerances shall be specified for the following parameters:
a) carcass: external diameter and ovalization;
N-2409 REV. A ENGLISH MAY / 2003
e) holding bandage: external diameter, number of layers, direction of application over the pipe body, pitch (or lay angle), and overlap.
7.8.2 The tolerance for the length of the flexible pipe (with end fittings assembled) shall be the following: +(0.5 % of the pipe length + 10 m)/-0 m;
7.8.5 The tolerance for the pipe OD is ± 5 % of the nominal value submitted by the manufacturer to the purchaser in the design report.
8 DOCUMENTATION
For the purpose of this Standard, the following section and subsection of standard ISO 13628-2 have been modified as written hereafter. Additional items to standard ISO 13628-2 are also found hereafter.
8.1 General
All the documentation mentioned in clause 8 shall be submitted to the purchaser. In addition, at any time, manufacturer shall promptly make it available to the purchaser on request.
8.1.2 Unless otherwise mutually agreed, manufacturer shall submit the purchaser (and also IVA, in case of prototypes), at the specified times, the following documents:
a) to e) remain unchanged;
f) as-built documentation: before the delivery of the pipe and any time on request;
g) operating manual: remains unchanged;
h) qualification test procedures, if production tests are required: prior to test run;
i) qualification test reports, if production tests are required: prior to commencement of manufacture or before the delivery of the pipe, as per contractual arrangement;
j) if the supply of prototype is allowed by the contractual arrangements, additional documentation, required by item 5.2.6: as per schedule of the prototype developing and qualification program mutually agreed at the commencement of contract.
8.1.3 Each pipe, ancillary component and accessory design shall have a specific identification number, generated by Manufacturer, associated to the its structure. The identification system of documents (data sheet, drawings) shall allow a quick recognition of its structural product design. New identification shall be attributed if any modification in the product design or manufacturing plant is carried out.
8.2 Design Premise
The design premise shall contain the parameters as specified in TABLE 15. If the manufacturer has made assumptions on any of the parameters in TABLE 15, then it shall be specified in the design premise that the values are assumed. The design premise shall include all technical requirements and recommendations contained in the purchaser specification.