Welding

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Minimum Requirements for Welding, Inspection and
TestingIn Accordance with ASME Sec-IX
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Welding

• A Process of joining two metal by the application
  of Heat and/or Pressure with or w/o addition of
  filler metal.
• Requirements to start Welding
• Procedure Qualification .
• Performance Qualification.

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Procedure Qualification

• The purpose of qualifying the procedure
  qualification is to demonstrate that the joining
  process proposed for construction is capable of
  producing joints having the required mechanical
  properties for the intended application.
• PQR (Procedure Qualification Record)
• WPS (Welding Procedure Specification)

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Procedure Qualification

• PQR The PQR is a record of variables recorded
  during the welding of the test coupons. It also
  contains the test results of the tested
  specimens.

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Procedure Qualification
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Procedure Qualification
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Procedure Qualification
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Procedure Qualification

• Acceptance Criteria for Tension Test
• In order to pass the tension test, the specimen
  shall have a tensile strength that is not less
  than
• The minimum specified tensile strength of the
  base metal or
• If the specimen breaks in the base metal outside
  of the weld or weld interface, the test shall be
  accepted as meeting the requirements, provided
  the strength is not more than 5 below the
  minimum specified tensile strength of the base
  metal.

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Procedure Qualification

• Acceptance Criteria for Bend Test
• The guided-bend specimens shall have no open
  discontinuity in the weld or heat-affected zone
  exceeding 1/8 in. (3 mm), measured in any
  direction on the convex surface of the specimen
  after bending.
• Open discontinuities occurring on the corners of
  the specimen during testing shall not be
  considered unless there is definite evidence that
  they result from lack of fusion, slag inclusions,
  or other internal discontinuities.

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Procedure Qualification
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Procedure Qualification

• WPS
• WPS is a written qualified welding procedure
  prepared to provide direction for making
  production welds to Code requirements.
• Contents of WPS
• The completed WPS shall describe all of the
  essential, nonessential, and, when required,
  supplementary essential variables for each
  welding process used in the WPS.

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Procedure Qualification
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Procedure Qualification

• There are three types of Welding variable for
  Procedure Qualification.
• Essential Variables.
• Supplementary Essential Variables.
• Non-essential Variables.

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Procedure Qualification

• Essential Variables
• Essential variables are conditions in which a
  change, as described in the specific variables,
  is considered to affect the mechanical properties
  (other than notch toughness) of the joint.
• Examples
• P. No.
• Base Metal Thickness.
• A. No.
• F. No.
• Pre-heat Temperature Decrease gt 55 C
• PWHT

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Procedure Qualification

• Supplementary Essential Variables
• Supplementary essential variables are conditions
  in which a change will affect the toughness
  properties of the joint, heat-affected zone, or
  base material..
• Examples
• Base Metal Group No.
• Diameter of Filler Metal gt 6mm
• Heat input.
• Current or Polarity.
• Change in position.

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Procedure Qualification

• Non Essential Variables
• Nonessential variables are conditions in which a
  change, as described in the specific variables,
  is not considered to affect the mechanical
  properties of the joint.
• Examples
• Groove Design.
• Diameter of filler metal
• Position
• Method of cleaning.
• Root spacing

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Performance Qualification

• The purpose of Performance Qualification is to
  determine the ability of welders and welding
  operators to make sound welds.
• WPQ (Welder Performance Qualification)
• WPQ shall include the essential variables the
  type of test and test results, and the ranges
  qualified.

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Performance Qualification

• The welder will weld a test coupon either pipe
  and Plate (according to job requirements) by
  using a approved WPS.
• Test Coupon shall be subjected to
• visual inspection
• Volumetric NDT examination (Min. 150mm) or
  Mechanical test.

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Performance Qualification

• Mechanical testing requirement for Welders
  qualification

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Performance Qualification

• Essential Variables (Performance)
• Essential variables are conditions in which a
  change, as described in the specific variable
  list, will affect the ability of the Welder to
  produce a sound joint.

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Performance Qualification
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Performance Qualification

• Pipe Diameter Range

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Performance Qualification

• P. No. Qualification Range

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Performance Qualification

• F. No.

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Performance Qualification

• Thickness Range

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Performance Qualification

• Positions Range

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Performance Qualification
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Inspection and Testing

• Hardness testing (HT)
• Positive Material Identification (PMI)
• Radiographic Testing (RT)
• Ultrasonic Testing (UT)
• Magnetic Particle Testing (MT)
• Dye Penetrant Testing (PT)
• Pressure Testing (Hydro or Pneumatic).

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Inspection and Testing

• Requirements for Hydro Test
• Test Manifold
• Pressure Gauge
• Pressure relief valve.
• Pressure and temperature recorder.
• Test Blinds.

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• The End