q01006 - visual weld exam (1)

Doc No: Q01006 Rev: Q of 17

Subject to contractual terms and conditions to the contrary, this document and all the information contained herein are the confidential and exclusive property of FMC Technologies, and may not be reproduced, disclosed, or made public in any manner prior to express written authorization by FMC.

VISUAL WELD EXAMINATION

Rev ECN No. Date Reviewed By Approved By Status

Q 1188070 09-APR-2012 Phillips, Sloan Glidden, Greg RELEASED

Summary:

This specification defines the requirements for visual weld examination of pressure containing, repair welds and weld metal corrosion-resistant alloy (CRA) overlay. Piping under 2-inches (51mm) in outer diameter is outside the scope of this specification.

Reviewed By:

Rocky McLain

April 9, 2012

ASNT Level III, #107750



Table of Contents

Section Title Page

1.0 SCOPE .......................................................................................... 4

2.0 REFERENCED SPECIFICATIONS ............................................... 4

3.0 PERSONNEL ................................................................................ 4

4.0 VISUAL EXAMINATION (VT) PROCEDURE ............................... 5

5.0 ACCEPTANCE CRITERIA ............................................................ 7

6.0 REPORTING ............................................................................... 14

7.0 Example Test Reports ............................................................... 14

8.0 Annex - Acceptable Oxidations of Welds in Stainless Steels ........................................................................................ 17



List of Figures

Figures Page

Figure 1: Symmetry of Fillet Welds (Reference from Norsok M101) ......................... 12

Figure 2: Roughness of Welds (Reference from Norsok M601) ................................ 12

Figure 3: Acceptable and Unacceptable Weld Profiles (Reference from AWS D1.1) ......................................................................................................................... 13



1.0 SCOPE

This specification addresses requirements for the visual examination of weld metal corrosion-resistant alloy (CRA) overlay, pressure retaining and structural welds including:

Qualification requirements for personnel performing the work.

Methods and techniques used to perform the work.

Acceptance criteria used to grade the work

This specification and procedure may be utilized for the performance of visual examinations by non-FMC NDE personnel. Alternatively, non-FMC procedures may be utilized for the performance of visual examinations if they have been submitted to and approved in writing by appropriate FMC personnel prior to use in production work.

2.0 REFERENCED SPECIFICATIONS

This specification is based on the following Codes of practice and FMC Specifications:

ASNT SNT-TC 1A Recommended Practice No. SNT-TC-1A (Current Edition) ASME V Article 9 Visual Examination (VT) AWS QC-1 Standard for AWS Certification of Welding Inspectors EN 473 Non-Destructive testing – Qualification and Certification of NDT

Personnel – General Principles EN 970 Non-Destructive Examination of Fusion Welds – Visual Examination NORSOK M601 Welding and inspection of piping NORSOK M101 Structural Steel Fabrication Q00295 NDT Requirements for Welds on Subsea Structural Fabrications

3.0 PERSONNEL

3.1 All companies performing NDE must be on the approved FMC Special Process Supplier List in order to perform work for FMC. Visual exams may be performed by personnel employed directly by the manufacturer or by an NDE Service Company. FMC and the manufacturer or NDE service company shall conduct random Independent NDE surveillance audits (field monitoring) of NDE Technicians performing visual examinations as per local work instructions.

3.2 Personnel performing visual examination inspection shall be VT level II qualified by the Manufacturer or NDE service company to perform the required inspections. Qualification of personnel may be done in accordance with a national certification scheme such as ASNT SNT-TC-1A, AWS D1.1 CWI,



British CSWIP, or EN 473. Alternatively NDE Service company or manufacturer personnel may be qualified to an in-house program prepared and administrated by their certified weld inspector or nationally accredited level III in visual weld examination specifically for the work to be performed. In-house programs are subject to approval by FMC. The work of VT technicians who are not CWI/Level III certified shall be subjected to random independent audits by their CWI/Level III.

3.2.1 Personnel performing visual inspections using camera systems shall have documented training in the use of the system prior to performing examinations.

3.3 Personnel performing visual examination shall have an eye examination on an annual basis and shall be able to demonstrate natural or corrected near-distance acuity in at least one eye per the following tests:

- Read a Jaeger number 1 test chart or equivalent at a distance of 12-15 inches.

Color Contrast Differentiation

This examination will demonstrate the capability of distinguishing and differentiating contrast among colors or shades of gray used in the method. This should be conducted upon initial certification and five-year intervals thereafter.

Vision examinations shall be administered by Ophthalmologists, Optometrists, other qualified medical professionals, ASNT/EN 473 Level III personnel, or other nationally accredited Level-III personnel.

4.0 VISUAL EXAMINATION (VT) PROCEDURE

4.1 The terms 'visual examination' and 'visual inspection' are both used by various codes, standards and specifications and have the same meaning in the context of inspection or examination of welds or parts. FMC uses the acronym VT to indicate either visual inspection or visual examination.

4.2 Techniques and Equipment

4.2.1 When performing final visual inspections for acceptance purposes, the inspection shall be carried out not less than 24 hours after weld completion.

In-process visual inspections and related repairs or rework may be performed at any time prior to the final visual inspection for acceptance purposes.

4.2.2 Prior to performing visual examination, welds and the adjacent area and temporary attachment removal areas shall be cleaned of any debris or surface contaminant that could obscure or mask a defect.



4.2.3 When direct visual examination is not possible, remote visual examination may be required using visual aids.

4.2.4 Translucent visual examination using artificial lighting with an illuminator may be used to supplement direct visual examination provided light intensity is sufficient and there is no glare or reflections to interfere with the examination.

4.2.5 Lighting shall be sufficient to illuminate the area of examination. Light intensity shall be a minimum of 100 foot candles (1000 lux).

4.2.6 Visual inspection using the naked eye shall be performed within 600 mm (24 inches) and at a maximum angle of 30 degrees to the weld being inspected.

4.2.7 Examinations may be performed using the naked eye or may utilize visual aids including:

Mirrors

Telescopes

Magnifying lenses

Remote visual devices such as camera systems, boroscopes or fiber optics.

Measuring devices such as rulers, depth gages, fillet weld gages, etc.

Note: When visual aids are used, they must provide resolution at least equal to that obtainable by direct visual examination.

4.2.7.1 Camera systems shall:

be capable of remote operation;

have 360 degree pan and tilt capability;

have high definition color linked to a high resolution monitor with recording capability;

normal viewing at 3x with 10x optical zoom;

built in laser profile assessment;

traction mechanism not harmful to the weld overlay

4.3 Scope of Examination – Pressure Containing and Structural Welds

4.3.1 Visual examination should include all permanent welds including attachment welds and adjacent base metal for a minimum of 2" (50mm) from the edge of



the weld. All areas of temporary attachment removal shall be examined regardless of their distance from the weld.

4.3.2 Fillet welds shall be measured to assure that they are sized in accordance with the drawing.

Convex fillet welds shall be measured with an appropriate gage to assure that the required leg length is obtained.

Concave fillet welds shall be measured with an appropriate gage to assure that the required minimum throat is achieved.

Fillet welds shall be examined to verify their symmetry.

4.3.3 When required by the drawing, surface finish shall be checked with appropriate gages to verify compliance with the required roughness.

4.4 Scope of Examination – Weld overlay

4.4.1 Pre-Overlay

Prior to weld overlay of base material all components to welded shall be subject to VT to ensure freedom from scale, laps, oxide, non-metallics, grease or other contaminants that may affect the welding process. Where necessary this examination shall be conducted with the aid of a high definition camera system.

4.4.2 Post-Overlay

Overlaid surfaces shall be 100% VT. Where necessary this examination shall be conducted with the aid of a high definition camera system.

Where weld overlay takes place internally, >1 meter in total length or, in locations such that viewing is restricted, examination shall be conducted with aid of camera system.

The camera system shall be capable of remote operation such that all relevant indications can be viewed on a monitor, recorded and the locations documented relative to circumferential and longitudinal datum points.

Weld overlaid areas, inspected by camera techniques, may be inspected in the as welded or machined conditions.

5.0 ACCEPTANCE CRITERIA

5.1 Visual examinations for structural welds, pressure retaining welds and corrosion-resistant alloy overlay shall be evaluated based on the acceptance criteria provided in Table 1, Table 2, Table 3, and Table 4 respectively.



5.2 Weld zones in stainless steel, nickel and titanium alloys shall be examined for oxidation on the inside and outside and evaluated based on color per the pictures in Annex A.

5.3 When visual examination reveals unacceptable defects or other issues of noncompliance, the weldment shall be repaired or remedial work performed until the requirements are achieved. Any repair welding shall be performed in accordance with a welding procedure approved for the project.

5.4 If repair welding or remedial work is performed to bring the item into conformance, the area shall be reexamined by VT.

5.5 Repairs or remedial work shall be documented as required for the project. When required, non-conformances shall be controlled and documented via Quality Notices in accordance with the FMC quality system

5.6 In-process remedial action such as grinding or removal of a weld for repair does not require visual inspection documentation via Quality Notices.



Table 1: Acceptance Criteria for Structural Welds

Type of Discontinuity

Acceptance Criteria

Inspection Category A & B (ref Q00295)

Inspection Category C, D & E (ref Q00295)

Crack None Allowed None Allowed

Incomplete Penetration or Lack of

Fusion None Allowed

Single Side Weld: Length < t/2, max 0.40" (10 mm) Defects shall be considered continuous defect if the distance between is <t

Undercut Max depth 0.010" (0.3 mm) Max depth 0.03125" (0.75 mm)

Rounded Indications (Surface Porosity)

None Allowed (1)

Accumulated pore diameters in any area of .40x6.0" (10x150mm) is not to exceed 0.60" (15mm). Max size of a single pore is t/4 or 0.160" (2mm) whichever is smaller.

Four or more relevant rounded indications in a line separated by less than 1/16" (1.5mm) edge to edge are unacceptable.

Exposed Slag Inclusion)

None Allowed None Allowed

(2) Excessive Penetration (Internal Root Protrusion)

t ≤ 0.250" (6mm) – 0.060" (1.5 mm) and smooth transition t > 0.250" (6mm) – 0.125" (3 mm) and smooth transition

Weld Profiles Weld profiles shall in conformance with Fig 3

Crater Cross Section All craters shall be filled to provide the specified weld size except for the ends of intermittent fillet welds outside their effective length

Roughness of Welds (Fig 2)

U" shall be less than 0.080" (2mm). Weld surface shall be smooth without sharp transitions. The bottom of roughness in butt welds shall not be below the base material surface

Misalignment of Butt Welds (Fig 3)

0.15t maximum or 0.160" (4 mm) whichever is smaller

(2) Reinforcement of Butt Welds (Fig 3)

"t" ≤ 0.40" (10mm) – max reinforcement 0.080" (2mm) "t" > 0.40" (10 mm) – max reinforcement 0.120" (3mm)

(2) Reinforcement (convexity) of Fillet Welds (Fig 3)

"c" ≤ 0.312" (8mm) – max reinforcement 0.062" (2mm) "c" > 0.312" (8 mm) < 1" (25mm) – max reinforcement 0.120" (3mm) "c" > 1.0" (25 mm – max reinforcement 0.200" (5mm)

Symmetry of Fillet Welds (Fig 1)

"a" ≤ to 0.25" (6mm) – max difference b-h: 0.120" (3mm) "a" > 0.50" (6 mm) < 0.60" (15mm) – max difference b-h: 0.20" (5mm) "a" > 0.50" (13 mm) – max difference b-h: 0.320" (8mm)

Fillet Weld Size (5)

(3),(4) Grinding Arc Strikes, Removal of Temporary Attachments

Grinding of base material shall not exceed 7% of the wall thickness or a max0.120" (3mm). Repair welding and inspection shall be performed if removal of the base metal exceeds the specified requirements

Sharp Edges Minimum 0.080" (2mm) radius

Notes: (1) Small surface indications may be evaluated by PT examination. Surface indications are permissible for butt and fillet welds if

the indication does not affect coating operations and it is found acceptable by PT examination. (2) Localized reinforcements exceeding above requirements are acceptable. (3) Temporary attachments shall be cut minimum 0.120" (3mm) from the base metal and ground smooth. The ground area shall

be visually inspected and in accordance with the inspection category required. (4) When required, grinding of the surface shall be specified. Typical examples of grinding are given in Norsok M101 Annex A. (5) When structures are manufactured to AWS D1.1 requirements, local undersized portions of fillet welds may be acceptable if

they are in compliance with the tolerances provided in AWS D1.1 Figure 6.1.



Table 2: Acceptance Criteria for Girth / Pressure Retaining Welds

Type of Discontinuity Acceptance Criteria

Crack None Allowed

Incomplete Penetration or Lack of Fusion

None Allowed

(1) Undercut None Allowed (1)

Rounded Indications (Surface Porosity) (6)

Overlay welds – none allowed within 1/8" (3mm) of a sealing surface Relevant indications (> 1/16" or 1.5 mm) are not acceptable (2)

Exposed Slag Inclusions None Allowed

(3) Concave Root (Suck Up)

The joint thickness including reinforcement must be equal to or greater than the minimum wall thickness.

(4) Excessive Penetration (Internal Root Protrusion)

t ≤ 0.250" (6mm) – 0.060" (1.5 mm) and smooth transition t > 0.250" (6mm) – 0.125" (3 mm) and smooth transition

Roughness of Weld U" shall be less than 0.080" (2mm). Weld surface shall be smooth without sharp transitions. The bottom of roughness in butt welds shall not be below the base material surface

Weld Profiles Weld profiles shall be in conformance with Fig 3

Crater Cross Section All craters shall be filled to provide the specified weld size except for the ends of intermittent fillet welds outside their effective length

Misalignment of Butt Welds (Fig 3)

0.15t maximum or 0.160" (4 mm) whichever is smaller

(4) Reinforcement of Butt Welds (Fig 3)

"t" ≤ 0.40" (10mm) – max reinforcement 0.080" (2mm) "t" > 0.40" (10 mm) – max reinforcement 0.120" (3mm)

(4) Reinforcement (convexity) of Fillet Welds (Fig 3)

"c" ≤ 0.312" (8mm) – max reinforcement 0.062" (2mm) "c" > 0.312" (8 mm) < 1" (25mm) – max reinforcement 0.120" (3mm) "c" > 1.0" (25 mm – max reinforcement 0.200" (5mm)

Symmetry of Fillet Welds (Fig 1)

"a" ≤ to 0.25" (6mm) – max difference b-h: 0.120" (3mm) "a" > 0.50" (6 mm) < 0.60" (15mm) – max difference b-h: 0.20" (5mm) "a" > 0.50" (13 mm) – max difference b-h: 0.320" (8mm)

(5) Grinding Arc Strikes, Removal of Temporary Attachments

Grinding of base material shall not exceed 7% of the wall thickness or a max 0.120" (3mm). Repair welding and inspection shall be performed if removal of the base metal exceeds the specified requirements

Sharp Edges Minimum 0.080" (2mm) radius

Notes: (1) Intermittent undercut (max length t/2 with max total t per 12' (300 mm)) to a maximum depth of 0.01" (0.3 mm) is permitted

for welds to pressure retaining material only if it does not reduce the wall thickness of the material below the design thickness. A QN must be raised for reach instance for review and approval by FMC Engineering.

(2) Small surface indications may be evaluated by PT examination. Surface indications are permissible for butt and fillet welds if the indication does not affect coating operations and it is found acceptable by PT examination.

(3) Suck up is allowed only if permissible external weld reinforcement compensates for suck up. (4) The weld specification or drawing/part report may require that the weld caps be ground flush before inspection. Localized

reinforcements exceeding above requirements are acceptable unless otherwise specified on the drawing/part report. (5) Temporary attachments shall be cut minimum 0.120" (3mm) from the base metal and ground smooth. The ground area shall

be visually inspected and in accordance with the inspection category required. (6) Butter weld surface indications revealed by finish machining are permissible up to the allowable size permitted by surface

MT or PT examination. It is desirable to grind indications on the weld bevel face prior to closure welding.



Table 3: Acceptance Criteria for Corrosion – Resistant Alloy (CRA) Overlay

Surface Preparation Prior To CRA Overlay Welding


Crack None Allowed

Surface Porosity / Voids

None Allowed

Final Visual Examination After CRA Overlay Welding


Undercut (1) None Allowed (1)

Rounded Indications (Surface Porosity)

Acceptance criteria is in accordance with Q02007

Exposed Slag Inclusions

Acceptance criteria is in accordance with Q02007

Notes: (1) Intermittent undercut (max length t/2 with max total t per 12' (300 mm)) to a maximum depth of 0.01" (0.3 mm) is

permitted for welds to pressure retaining material only if it does not reduce the wall thickness of the material below the design thickness. A QN must be raised for reach instance for review and approval by FMC Engineering.

Table 4: Acceptance Criteria for Corrosion – Resistant Alloy (CRA) Overlay (as-welded surfaces)

Surface Preparation Prior To CRA Overlay Welding


Crack None Allowed

Surface Porosity / Voids None Allowed

Final Visual Examination After CRA Overlay Welding


Inter-run Lack of Fusion None Allowed

Missing first or subsequent layer

None Allowed

Oxidation and Surface breaking inclusions

None Allowed

Un-fused Wire None Allowed

Autogenous welding(1) None Allowed

Poor stop/start Profile(2) None Allowed

Excessive bead width(3) In excess of width specified in WPS



Surface Blistering or Cracking

None Allowed

Craters or Blowholes None Allowed

Porosity None Allowed

(1) Unless qualified for start/stops or cosmetic repairs (2) Typical and acceptable stop/start profiles are to be defined during MPQ (3) > than specified in WPS

Figure 1: Symmetry of Fillet Welds (Reference from Norsok M101)

Figure 2: Roughness of Welds (Reference from Norsok M601)



Figure 3: Acceptable and Unacceptable Weld Profiles (Reference from AWS D1.1)



6.0 REPORTING

The visual examination acceptance is normally documented on the surface NDE report or weld map. A separate report could be required for specific projects. Confirmation of acceptable visual examination shall be documented as required by the specific project. Documentation may be accomplished by:

Sign-off on the weld map for the assembly or part.

Sign-off on Routers or Inspection & Testing checklists

Visual examination reports

NDE records, if required, must be verified by QA and retained as permanent records for a minimum of 5 years.

7.0 Example Test Reports

Here are two examples from Houston and Singapore:



8.0 Annex - Acceptable Oxidations of Welds in Stainless Steels

(Reference from Norsok M601) Fig. 1 a) to g). All pictures show root side of welding process 141 TIG weld with Argon shielding gas. Picture a) to d) shows examples of acceptable oxidation, while picture e) to g) shows examples of unacceptable oxidation.

q01006 - visual weld exam (1)

Documents

q page

q01006 rev

express written authorization

contractual terms

repair welds

structural welds

roughness of welds reference

status q