3.00.operatingprocedures.establishing qualified welding procedure specifications

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3.00 WELDING PROCEDURES MANUAL of 5

OPERATINGPROCEDURES

ESTABLISHING QUALIFIED WELDINGPROCEDURE SPECIFICATIONS

12/31/06

HIS SECTION PROVIDES STANDARD FOR ESTABLISHING Qualified WeldingProcedures and summaries of the Qualified Welding Procedure Specifications (QWPS)

used by the Company. TGENERAL

The individual overseeing welding activities will establish and qualify detailed welding

procedure specifications for each welding process approved for use by persons performing

welding on the Company’s natural gas and/or propane facilities.

Weld quality will be determined by destructive testing in accordance with Section 3.01

(“Destructively Testing Welds”). Sample test welds shall be joined by following the QWPS.

Welds must be made by an experienced welder. Weld test specimens will be broken,

pulled or bent, and examined by a qualified Company representative.

QWPS must be completed for each welding procedure in accordance with the welding

process and the pipe and fitting materials used and maintained as long as the procedure is

current.

QWPS include essential and non-essential variables. Essential variables are those factors

which must be recorded and if they are changed in any way, the procedure must be

retested and re-qualified. Nonessential variables are usually of less importance and may

be changed within prescribed limits and the procedure need not be re-qualified.

If questions arise regarding specific variables within the procedure, contact the individual

overseeing welding activities for guidance.

WELDING PROCEDURE SPECIFICATIONS

QWPS established by the Company (see Section 2.20: Qualified Welding ProcedureSpecifications [QWPS]) include:

Weld Process Manual, semi-automatic, or automatic welding process

Pipe and Fitt ing Materials Materials to which the procedure applies

Pipe Diameters and WallThickness

Pipe diameter and wall thickness used for qualification of the procedure

Pipe Grades Qualified Pipe grades qualified by a Qualified Welding Procedure

Pipe Diameters Qualified Pipe diameters of qualified by a Qualified WeldingProcedure

Wall Thickness Qualified Pipe wall thicknesses qualified by a Qualified WeldingProcedure




OPERATINGPROCEDURES


12/31/06

Joint Design Sketch(es) of the joint illustrating the angle of bevel, thesize of the root face and root opening or the spacebetween abutting members, and the shape and size of thefillet welds

Position Welding position (rolled or horizontal fixed) to be used

Direction of Welding Welding direction (uphill or downhill) to be used

Electrical Characteristics Designation of current and polarity for each electrode,rod, or wire

Minimum Number of Welders

Minimum number of welders required for a particular weldprocess

Type of Lineup Clamp Indication of whether the lineup clamp is to be external,internal, or not required

Removal of Lineup Clamp If a clamp is used, the minimum percentage of root-beadwelding that must be completed before the clamp isreleased

Filler Metal Change from one filler metal classification group to anotheras referenced in API 1104; any electrode type other thanthose specified in the qualified welding procedure willrequire re-qualification:

Group 1 (E6010, E7010)

Group 2 (E8010, E9010) Group 3 (E7018, E8018, E9018)

Group 5 (ER80SD2, ER90S-G)

Group 6 (RG60, RG65)

Electrode Size Size (diameter) of the welding electrode used for thewelding process

Number of Beads(Passes)

Minimum number and sequence of beads (passes)

Voltage Voltage range for each electrode, rod, or wire

Amperage Amperage range for each electrode, rod, or wire

Shielding Gas and FlowRate

Composition of the shielding gas and the range of flowrates

Time Between Passes Maximum time between the completion of the root beadand the start of the second bead, as well as the maximumtime between the completion of the second bead and thestart of subsequent beads

Speed of Travel Range for speed of travel (in inches per minute), for eachpass




OPERATINGPROCEDURES


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Pre- and Post-HeatTreatment Methods, temperature, temperature-control methods, and

ambient temperature range for pre- and post-heattreatment

Temperature Contro lMethod

Method of determining the temperature of the base metalusing a pyrometer or temperature indicating crayon

Cleaning and/or Grinding Method(s) used for cleaning, grinding, or both

Gas and Pressure Identification of the gases used in the Oxy-acetyleneprocess, and the pressures of each respective component

Flame Characteristics Neutral flame to be utilized

CHANGES REQUIRING RE-QUALIFICATION

Essential variables requiring re-qualification of a procedure when changed include:

Joint Design Major change in joint design (e.g., from V-groove to U-groove or use a backing strip)

NOTE: Minor changes in the angle of bevel or the land of the welding groove do not require re-qualification

Position Change in position from roll to fixed, or vice versa

Wall Thickness Change in nominal pipe wall thickness per these

groupings: Less than 3/16 (0.188) inch

From 3/16 (0.188) inch through 3/4 (0.750) inch

Greater than 3/4 (.0750) inch

Filler Metal Change from one filler metal classification group to anotheras referenced in API 1104. Any electrode type other thanthose specified in the qualified welding procedure willrequire requalification.

Electrical Characteristics Change from DC electrode positive to DC electrode negativeor vice versa, or a change from DC to AC current or viceversa

Time Between Passes Increase in the maximum time between completion of theroot bead and the start of the second bead

Direction of Welding Change in the direction of welding from vertical downhill tovertical uphill, or vice versa

Shielding Gas and FlowRate

Change from one shielding gas to another or from onemixture of gases to another, and/or a major increase ordecrease in the range of flow rates for shielding gases




OPERATINGPROCEDURES


12/31/06

Speed of Travel Change in the range for speed of travelWelding Process or

MethodChange in the welding process or method of application

Base Material Change in the base material per these material groupings:

SMYS less than or equal to 42,000 psi

SMYS greater than 42,000 psi but less than 65,000 psi

SMYS greater than or equal to 65,000 psi (each grade toreceive a separate requalification test)

NOTE: Procedures must be qualified using the highest

specified yield strength pipe.

WELDING PROCEDURE SPECIFICATIONS FOR IN-SERVICE WELDING

QWPS established by the Company for in-service weld processes (see Section 2.20:“Qualified Welding Procedure Specifications”) include:

Pipe and Fitt ing Materials Carbon equivalence and specified minimum yield strength

Pipeline OperatingConditions

Pipeline operating conditions (e.g., pipe content, flow rate,etc.) identified and grouped

Heat Inpu t Range Required heat input to overcome the effect of flowingcontents

Weld Deposit ion Sequence Weld deposition sequence and temper bead proceduresshould be specified

NOTE: Carbon equivalence (CE) can be derived by calculating from the chemicalcomposition analysis sent from the pipe mill:

CE = C + (Mn/6) +.03

Where: C = CarbonMn = Manganese

Do not accept carbon equivalence above .40 when purchasing any material forwelding.

NOTE: Heat input range calculations can be derived from the following calculations:

Minimum amperage (A) x minimum voltage (V) x 60 = _____ kJ /in. min.Maximum travel speed (IPM) x 1000

Maximum amperage (A) x maximum voltage (V) x 60 = _____kJ /in. max.Minimum travel speed (IPM) x 1000

Range = ____ kJ /in. min. to kJ /in. max.




OPERATINGPROCEDURES


12/31/06

CHANGES REQUIRING RE-QUALIFICATION FOR IN-SERVICE WELD PROCESSES

Essential variables requiring re-qualification of an in-service weld procedure when changedinclude:

Pipe and FittingMaterial

Carbon equivalence may be grouped. For in-service filletwelds, specified minimum yield strength is not an essentialvariable

Pipeline OperatingConditions

Severity of pipeline operating conditions (in terms of coolingrates) above the group qualified

Wall Thickness For in-service fillet welds, wall thickness is not an essentialvariable, though it is an essential variable for welding on linesnot in service

Weld DepositionSequence

Change from the specified weld sequence to anothertempering bead sequence

CHANGES NOT REQUIRING REQUALIFICATION

Nonessential variables that do not require requalification when changed include:

The size of the electrode or filler wire

Certain details of the weld joint design

3.00.operatingprocedures.establishing qualified welding procedure specifications

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