Section 12 Mechanized Welding with Filler Metal Additions

Quiz- Section 12 Mechanized Welding with Filler Metal Additions- CWI Part C- 5 Questions

1.

For the qualification of mechanized pipe welding procedures, the use of a lineup clamp:

 
 
 
 
 

2.

Which of the following is not an essential variable for a welding procedure specification for mechanized welding processes?

 
 
 
 
 

3.

Radiographic testing of welds made by mechanized processes shall be in accordance with:

 
 
 
 
 

4.

On a welding procedure specification for mechanized welding, the travel speed:

 
 
 
 
 

5.

Which of the following is not an essential variable for the qualification of mechanized welding procedure specifications?

 
 
 
 
 


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Section 12: Mechanized Welding with Filler Metal Additions

Section 12 provides the rules for qualifying welding procedures and personnel for mechanized welding with filler metal additions. It further addresses production welding along with inspection and NDT of production welds..

12.1 Acceptable Processes

Mechanized welding shall be performed using one or more of the following processes:

(a) Submerged arc welding (SAW).
(b) Gas metal arc welding (GMAW).
(c) Gas tungsten arc welding (GTAW).
(d) Flux-cored arc welding (FCAW) with or without external shielding gas.
(e) Plasma arc welding (PAW).
(f) Any of the above processes combined with a manual or semiautomatic process.

12.2 Procedure Qualifications

The rules in Section 1 2 are basically identical to those in Section 5 with a few additions and exceptions. Only the differences from Section 5 will be discussed here.

The quality of test welds shall be determined by both destructive testing and non-destructive testing and shall meet the requirements of subsection 5.6, except that nick break tests are not required, and Section 9. The use of nondestructive testing is in addition to the destructive tests required in Section 5.

12.3 Record

Identical to Section 5, this subsection refers the reader to Figures 1 and 2 on pages 1 0 and 1 1 for recommended forms that can be used to document a welding procedure specification and the record of the procedure qualification test coupon, respectively. The record of the procedure qualification must be maintained as long as the welding procedure specification is in use.

2.4 Welding Procedure Specification

Subsection 1 2.4 lists the variables required to be recorded on a welding procedure specification for mechanized welding. The list is the same as that in subsection 5.3, with the following additions and exceptions:

(a) This section does not provide suggested groupings for diameters or wall thicknesses.
(b) Paragraph 1 2.4.2.1 requires the welding procedure specification to include a description of the equipment to be used.
(c) Paragraph 1 2.4.2.4 requires that the welding machine used for each bead be recorded on the welding procedure specification.
(d) Flame characteristics are not listed in subsection 1 2.4 because oxyfuel welding cannot be mechanized.
(e) The minimum percentage of root bead welding that must be completed before a lineup clamp can be removed is not listed in paragraph 1 2.4.2.1 1.
(f) Paragraph 1 2.4.2.1 2 includes the requirements for joint end and inter pass cleaning but does not require that the type of cleaning tools (power or hand) be specified on the welding procedure specification.
(g) Paragraphs 1 2.4.2.1 3 and 1 2.4.2.1 4 require the width of material to be heated during preheating and PWHT to be specified on the welding procedure specification.
(h) Paragraph 1 2.4.2.1 9 requires the welding procedure specification to list any other important factors necessary to produce a good weld and gives examples.

2.5 Essential Variables

Subsection 1 2.5 lists the essential variables for the qualification of welding procedures using mechanized welding processes. This list is essentially the same as that in subsection 5.4 with the following additions and exceptions:

(a) Paragraph 1 2.5.2.3 adds that any change to the root spacing, root face, or angle of bevel to a value not specified on the welding procedure specification is an essential variable.
(b) Paragraph 1 2.5.2.4 adds that any change in wall thickness beyond the range listed in the welding procedure specification is an essential variable.
(c) Paragraph 1 2.5.2.5 adds that any change in specified pipe OD beyond the range listed in the welding procedure specification is an essential variable.
(d) Paragraph 1 2.5.2.7 adds that a change in the size of the filler metal wire is an essential variable.
(e) Change in welding position is NOT an essential variable.
(f) Paragraph 1 2.5.2.1 0 specifies that a change in the range of flow rates established for the shielding gas is an essential variable (whereas subsection 5.4 addresses a specific percentage change).
(g) Paragraph 1 2.5.2.1 6 adds that, for plasma arc welding, any change in the orifice gas nominal composition or change in the orifice diameter is an essential variable.

12.6 Qualifications of Welding Equipment and Operators

This subsection lists the essential variables and the tests required to qualify the welding operators.

Paragraph 1 2.6.1 provides the general rules applicable to welding operator qualification. Similar to Section 6, welding operators shall be qualified by welding a test coupon which shall be tested either by destructive methods or nondestructive methods, or both and shall meet the requirements of subsection 6.4 (visual examination) and either 6.5 (mechanical testing) or 6.6 (radiographic testing), except that nick break tests are not required. When required, tensile strength tests may NOT be omitted in lieu of nick break tests. In addition, welding operators shall be qualified on the type of equipment to be used in production welding.

Paragraph 1 2.6.2 lists the essential variables for welding operator qualification. They are:
(a) A change from one welding process, mode of transfer, polarity, or method of application to another.
(b) A change in the direction of welding from vertical uphill to downhill or vice versa.
(c) A change in the filler metal type (solid wire, metal-cored, flux-cored, etc. ).
(d) A change from one specified OD group to another where the OD groups are defined as:
1 ) OD less than 1 2.75 inches.
2) OD equal to or greater than 1 2.75 inches.
(e) An increase in wall thickness over that welded during the qualification test.
(f) A change in position from that qualified (a change from rolled to fixed or a change from vertical to horizontal). A welding operator who qualifies in the fixed position shall also be qualified to perform welds in the rolled position.

(g) A change in welding bug manufacturer or model.
(h) A change in the method of applying the root bead (e.g., external root versus internal root).
(i) A major change in joint design (e.g. from a V-groove to a U-groove) or any change beyond the range established for root spacing, root face, or angle of the bevel.
(j) At the option of the company, welding operators whose work is limited to specific passes in a multi-pass butt weld may qualify by depositing only those passes in a joint, with other passes necessary to complete the joint being wielded by others.

2.7 Records of Qualified Operators

A record shall be made of the tests and results required by subsection 1 2.6. A form similar to that shown in Figure 2 on page 1 1 should be used, but any form is suitable as long as it records all of the required information. A list of qualified operators and the procedures for which they are qualified shall be maintained. An operator may be required to requalify if a question arises about his competence.

12.8 Inspection and Testing of Production Welds

Production welds shall be inspected and tested in accordance with Section 8.

12.9 Acceptance Standards for NDT

Acceptance criteria for production welds shall be those found in Section 9 or, at the company’s option, Annex A.

12.1 0 Repair and Removal of Defects

Repair and removal of defects shall be in accordance with Section 10.

12.1 1 Radiographic Testing

Radiographic testing procedures shall be in accordance with subsection 1 1 .1.

12.1 2 Ultrasonic Testing

Ultrasonic testing procedures shall be in accordance with subsection 1 1 .4.

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Section 10 Repair and Removal of Weld Defects- CWI Part C

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Section 1 0: Repair and Removal of Weld Defects

0.1 General

Paragraph 1 0.1 states that weld defects may be identified at any time.

1 0.2 Authorization for Repair

Paragraph 1 0.2.1 states that company authorization is required for crack repairs, back weld repairs, and double repairs. Company authorization is not required for any repair that does not require the application of heat or weld metal, such as grinding or fling.

Paragraph 1 0.2.2 gives the conditions under which company-authorized repairs can be made to cracked welds. In general, if the length to be repaired is less than 8 % of the weld length, the repair is permitted if a qualified repair procedure is used.

Paragraph 1 0.2.3 addresses repair of defects other than cracks and states that these defects in the root, filler and finish beads may be repaired with prior company authorization. A qualified repair procedure is required for repair welds when using a welding process, method of application, or filler metal different than that used for the original weld, or when repairs are made in a previously repaired area, or when required by the company.

Paragraph 1 0.2.4 permits the use of grinding to remove defects in the reinforcement of root beads and cover passes, as long as contour, minimum wall, and weld thickness requirements are not violated.

Paragraph 1 0.2.5 permits the repair of back welds as long as a qualified repair welding procedure is used and the company permits the repair.

Paragraph 1 0.2.6 requires prior company authorization for double repairs. Further repair of a double repair is only permitted with company authorization and when the repair procedure to be used has been qualified by replicating the number of thermal cycles that the pipe will have seen after the repair.

Paragraph 1 0.2.7 places limits on the lengths of repairs. For pipes having a specified OD of 2.375 inches and greater, the limit on the length of repairs shall be established by the company. For pipes having a specified OD of less than 2.375 inches, all repairs require prior company authorization.

Paragraph 1 0.2.8 establishes a minimum required repair length of 2 inches unless the company
authorizes a shorter repair.

1 0.3 Repair Procedure

This section provides detailed requirements for qualifying repair welding procedures. Repairs are categorized as full-thickness repairs, internal partial-thickness repairs, external partial-thickness repairs, cover pass repairs, or back weld repairs, and the type and number of test specimens required for each type of repair procedure are given in Table 5 on page 49, with detailed instructions in paragraph 1 0.3.3. The tests required are fewer in number to, and different than, the tests required to qualify a butt weld procedure in Table 2. This table adds macro sections and hardness tests for all of the repair procedures but Charpy impact specimens are only required if the original production welding procedure was qualified with Charpy impact tests and when specified by the company.

Paragraph 1 0.3.4 lists the information required to be on a repair welding procedure and includes:

(a) Location and method for exploration of the defect.
(b) Method of defect removal and subsequent inspection for verification of removal.
(c) Requirements for preheating and inter-pass temperature.
(d) Welding processes and all of the other specification information required in paragraph 5.3.2.
(e) Requirements for inter pass NDT, if applicable.
(f) Methods for filler metal control or storage, including electrodes, fluxes, and/or shielding gases
when hydrogen control is recommended by the manufacturer.
(g) Repair type and procedure limitations.
(h) Time delay before final inspection, when required.

Paragraph 1 0.3.5 adds three new essential variables to the list in paragraph 5.4.2: (1 ) the location of excavation in paragraph 1 0.3.5.2, (2) type of repair in paragraph 1 0.3.5.3, and (3) the preheat and inter pass temperature in paragraph 1 0.3.5.4

Paragraph 1 0.3.6 addresses the welding of the test joint and specifies a minimum length of 8 inches. In addition, multiple repair procedures may be qualified in a single test joint.

Paragraph 1 0.3.7 addresses the testing of the weld joints and provides specific requirements for visual examination and the hardness tests to be conducted on the macro sections. Hardness tests are required for both the deposited weld metal and the heat-affected zones of the macro sections at the locations specified in Figures 21 through 26 on pages 51 through 53, depending on the type of repair. Hardness tests shall be conducted per ASTM E384 using a Vickers indenter and a 1 0 kg load. Maximum hardness values shall not exceed those listed in Table 6 on page 54, but the company can specify other maximum hardness values if they choose to do so. When hardness testing is required, chemical analysis is also necessary to determine the carbon equivalent of the base metal.

Charpy impact testing shall also be performed when the production welding procedure was qualified by Charpy impact tests and shall be performed at locations specified by the company. The company shall specify the minimum design temperature at which the specimens shall be tested and the minimum required absorbed energy for those tests.

1 0.4 Repair Welder Qualification

This subsection lists the rules for qualifying welders who perform repair welds. Welders performing repair welds must have an existing qualification to subsections 6.2 or 6.3 in addition to the requirements in this subsection. The welder must then make an additional qualification weld using the applicable repair welding procedure and the number and type of test specimens required are provided in Table 7 on page 54 for the specific type of repair welding procedure.

Paragraph 1 0.4.3 gives the changes in essential variables that would require the requalification of repair welders. They are:
(a) Any change from one repair type to another except qualification on a full-thickness repair qualifies all partial-thickness repairs.
(b) A change in filler metal groups as defined in Table 1.
(c) An increase in depth of the repair area greater than twice that deposited in the qualification weldment.
(d) A change in position from that for which the repair welder has already qualified.

1 0.5 Supervision

Repair welds shall be made under the supervision of an individual experienced in repairs who is acceptable to the company. Inspection of repairs and the qualification of those conducting the inspections shall be as specified by the company. Repairs shall be documented and the records maintained by the company.

1 0.6 Acceptance Criteria

Repaired areas shall be inspected by and evaluated in accordance with the same NDT methods and acceptance criteria as used for the original weld. NDT of a repair weld must include the entire length of the repair plus the greater of 2 inches or 1 0 % of the repaired length on both ends of the repair.

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Section 6 Qualification of Welders – CWI Part C

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Section 6: Qualification of Welders

6.1 General

The purpose of welder qualification is to prove the welder’s ability to make sound welds using qualified procedures. Welders must qualify by testing before they perform any production welding. A welder who satisfactorily completes a welding procedure qualification test is also qualified as long as all of the test specimens required by subsection 6.5 are successfully tested. These standards also require qualification to be conducted in the presence of a representative acceptable to the company.

The essential variables for welder qualification are different than the essential variables for procedure qualification. The essential variables for welder qualification are listed in paragraphs 6.2.2 and 6.3.2 and will be discussed in detail below.

There are two options for qualifying welders: (1 ) a single qualification and (2) multiple qualifications.
The multiple qualifications qualify the welder for the widest range of variables and is generally preferred.

6.2 Single Qualification

Single qualification requires separate qualification tests for fillet and groove welds. Note that a fillet weld qualification will qualify for welding both socket welds and branch connection welds. However, butt welds do not always qualify the welder to make fillet welds in API 1104.

Paragraph 6.2.1 describes the requirements for the single qualification. In this test, the welder qualifying to make butt welds will make a butt weld in either the fixed or rolled position with the axis of the pipe either horizontal, vertical, or inclined from horizontal at an angle of no more than 45 degrees. The welder qualifying to make branch connections or fillet welds will make a branch or socket connection weld in the position and orientation specified by the welding procedure. The test welds shall meet the requirements of subsection 6.4 (visual examination) and either subsection 6.5 (destructive testing) or 6.6 (nondestructive testing for butt welds only).

Paragraph 6.2.2 is entitled “Scope,” but it really just lists the essential variables for the single qualification of welders. The welder who has completed the single qualification test must requalify if he changes any variables outside the following ranges:

(a) A change in the welding process or combination of welding processes (with the exception that a welder qualified separately for each process used in the combination is also qualified to use the processes in combination).
(b) A change in the direction of welding from uphill to downhill or vice versa.
(c) A change in filler metal classification from Group No. 1 or Group No. 2 to any other group or from any Group No. 9 filler metal to a Group No. 1 or Group No. 2 filler metal. Note that this implies that a welder qualified for SMAW may switch between Group No. 1 electrodes (E601 0, E6011, E701 0, and E701 1 ) and Group No. 2 electrodes (E801 0, E801 1, and E901 0) without having to requalify. However, if a welder qualifies for SMAW using a low-hydrogen electrode (Group No. 3), he must requalify to weld using an E601 0 electrode (Group No. 1 ). In addition, each filler metal classification not listed in Table 1 requires a separate qualification.
(d) A change from one OD group to another (note that OD group was NOT an essential variable for the qualification of welding procedures).
(e) A change from one wall thickness group to another.
(f) A change in position with the following exceptions: a welder who qualifies for fixed (position) welding is also qualified to perform roll welding; a welder who qualifies for making butt welds is also qualified to make lap fillet welds (socket welds), but NOT branch connection welds; a welder who qualifies by making a butt weld in the fixed position at a 45 ° angle is qualified to make butt welds and lap fillet welds (but NOT branch connection welds) in all positions.
(g) A change in the joint design, such as the deletion of a backing strip or a change in edge preparation from a V bevel (i.e. V groove) to a U bevel (i.e. U groove), although this variable is rather
vague.

6.3 Multiple Qualification

Multiple qualifications qualify a welder to weld in all positions, on all wall thicknesses, joint designs, and fittings. However, the widest range of pipe diameters qualified depends on the diameters he welded during the test.

Paragraph 6.3.1 describes the requirements for the multiple qualifications, which require the welder to complete two test weld joints. They are:

(a) A butt weld in the fixed position with the axis of the pipe either horizontal or inclined from horizontal at an angle of no more than 45 degrees. The weld shall be made on pipe with a minimum outside diameter of 6.625 inches and a minimum wall thickness of 0.250 inches. The weld is also required to be welded without a backing strip.

The weld must meet the requirements of API 1 1 04 subsection 6.4 (visual examination) and either subsection 6.5 (destructive testing) or 6.6 (nondestructive testing).

(b) A branch-on-pipe connection weld, for which the welder is required to layout, cut, fit, and weld two pipes of equal diameter together in the form of a T (see Study Guide Figure 5.1 ). The weld shall be made with the axis of the run pipe horizontal and with the branch connection extending vertically down, such that the weld is made in the overhead position.

In addition to the workmanship requirements of paragraph 6.3.1, four nick break specimens shall be removed from the weld as shown in Figure 1 0 and they must also meet the nick break test requirements of subsection 5.8.3.

Paragraph 6.3.2 describes the essential variable rules for multiple qualifications. A welder who successfully completes the butt weld test on pipe 1 2.750 inches in diameter or larger and the branch connection weld on pipes 1 2.750 inch in diameter or larger is qualified to weld in all positions, on all wall thicknesses, joint designs, fittings, and on all pipe diameters. Successful testing on pipes smaller than 1 2.750 inches in diameter qualifies for welding in all positions, on all wall thicknesses, joint designs, fittings, and on all pipe diameters equal to or less than that on which he tested.

A welder holding multiple qualifications shall be required to be requalified if any of the following are changed:

(a) A change from one welding process to another process or combination of processes (aging with the exception that a welder qualified separately for each process used in the combination is also qualified to use the processes in combination).
(b) A change in the direction of welding from uphill to downhill or vice versa.
(c) A change in filler metal classification from Group No. 1 or Group No. 2 to any other group or from any Group No. 3 through 9 to Group No. 1 or Group No. 2. Also, a change in filler metal classification not listed in Table 1 to any other filler metal or vice versa.

6.4 Visual Examination

Visual examination of the test weld must precede any preparation of samples for mechanical testing. If the visual examination reveals cracks, inadequate penetration, burn-through, or unacceptable amounts of undercut, rejection is automatic and another test weld must be prepared. In addition, an inspector may reject the weldment if it does not present a neat, workman-like appearance. Welds made by semiautomatic (e.g. GMAW) or mechanized (e.g. SAW) processes may be rejected if too much filler wire protrudes into the interior of the pipe (sometimes referred to as “bird’s nests” or “whiskers”), although API 1104 offers no definition of what “shall be kept to a minimum” means.“

6.5 Destructive Testing

Paragraph 6.5.1 details the testing requirements for butt weld qualifications. Test specimens shall be cut from the test welds at the locations shown in Figure 1 2 on page 28. The number and type of specimens required are listed in Table 3 on page 30. Figure 1 2, Table 3, and paragraph 6.5.1 should be used together for determining welder qualification test requirements. The test specimen locations are exactly the same as those required for procedure qualification, shown in Figure 3 on page 1 8. The number and type of specimens required for welder qualification, however, are slightly different. Table 3 for welder qualification on page 30 is arranged the same as Table 2 for procedure qualification on page 1 9. The only difference is in the number of specimens required. The similarity of these two tables makes them easy to confuse. Make sure you are referencing the correct table in API 1104: Table 2 on page 1 9 when welding procedures are being qualified and Table 3 on page 30 when welders are being qualified.

Since smaller pipes have less material from which to remove specimens, for pipes less than 2.375 inches in OD, it may be necessary to weld an additional test joint to obtain the required number of test specimens. Furthermore, for pipe 1 .31 5 inches in OD or less, footnote a of Table 3 on page 30 (and Note 2 of Figure 1 2 on page 28 and paragraph 6.5.1 ) provides the option of pulling a single full-section tension test specimen in lieu of performing the required two root bend and nick break tests.

When welders qualify by making butt welds, paragraph 6.5.2 states that the specimens shall be prepared for tensile strength, nick break, and bend tests, as applicable, and the tests shall be performed as described for procedure qualification testing in subsection 5.6. Since the purpose of welder qualification is to determine the welder’s ability to deposit sound weld metal, it is not necessary to determine the tensile strength of the tension test specimens. The tension test may even be omitted, in which case the specimens designated for the tension test shall be subjected to the nick break test.

The tensile strength test requirements for welder qualification are detailed in paragraph 6.5.3. This test is really just a weld metal soundness test. If any of the reduced-section specimens or the full section specimen fails in the weld or at the junction of the weld and the base metal, the fractured surface must meet the soundness requirements of paragraph 5.6.3.3, which is the acceptance criteria for the fractured surface of a nick break specimen. If the specimen fails in the parent material, the weld metal is considered to be acceptable.

Paragraph 6.5.4 gives the requirements for the nick break tests for welder qualification and states that these specimens must meet the same acceptance criteria as those for procedure qualification. See paragraph 5.6.3.3.

The requirements for the bend tests for welder qualification are given in paragraph 6.5.5, which references the same acceptance criteria as those for procedure qualification in paragraphs 5.6.4.3 or 5.6.5.3, as applicable. However, there are two exceptions: Welds in the high-strength pipe may crack or break before they bend to a full U shape. In that case, the specimen is acceptable as long as the exposed surfaces meet the requirements for nick break tests as given in paragraph 5.6.3.3. The other exception is that the company may permit the testing of an additional bend specimen removed from the same test weld to replace a failed bend specimen if, in their opinion, the failure was not representative of the weld. The welder shall be disqualified if this additional specimen fails.

Paragraph 6.5.6 requires that fillet welds be tested using nick break specimens, as shown in Figure 1 0 on page 25. Four specimens shall be removed from locations approximately 90 degrees apart to qualify each welder.

Paragraph 6.5.7 gives the instructions for cutting, preparing, and testing the nick break specimens for welder qualification. When specimens are removed from a complete circumferential test weld, subsection 5.8 and Figures 1 0 and 1 1 on page 25 apply. If the test weld consists of multiple pipe segments (weldments), each segment must supply the same number of specimens. The acceptance criteria for each specimen are given in paragraph 5.8.3.

6.6 Nondestructive Testing (NDT) – Butt Welds Only

At the company’s option, the qualification butt weld may be examined by radiographic testing or automatic ultrasonic testing instead of mechanical testing and meet the requirements in 9.3 or 9.6, respectively. It is not permitted to use NDT methods to purposely locate sound areas or defective areas and subsequently making tests of such areas to qualify or disqualify a welder. Be aware that jurisdictional limitations may override API 1 1 04 and, in doing so, may restrict the use of NDT methods in lieu of mechanical testing for welder qualification.

6.7 Retesting

If a welder fails a test but the company and the welder’s representatives mutually agree that the welder wasn’t at fault, the welder may be given a second chance to qualify. If the welder fails the second time, the welder must submit proof of additional welder training that is acceptable to the company before taking the test for the third time.

6.8 Records

A record that documents the test results for each welder shall be maintained. Furthermore, a list of welders and the procedures for which they are qualified shall also be maintained. If the abilities of a welder come into question, the welder may be required to requalify.

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Section 4: Specifications – CWI Part C

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Section 4: Specifications

4.1 Equipment

This subsection calls for good judgment, sound engineering, suitable operating practices, and attention to safety in the operation of welding equipment. Arc welding equipment shall be operated within the voltage and current ranges specified on the welding procedure specification. Gas welding equipment shall be operated with the fame characteristics and tip sizes given in the qualified WPS.

4.2 Materials

Paragraph 4.2.1 says that pipe and fittings must conform to API or any applicable ASME, ASTM, MSS, or ANSI specifications, but it then further states that materials that comply with the chemical and mechanical properties of any of these specifications are also acceptable, even if they are not manufactured in accordance with the specification. This suggests that the chemical and mechanical properties of any such material must be identified, preferably on the welding procedure specification, when used for an API 1104 application.

Paragraph 4.2.2.1 states that filler metals must conform to one of the listed AWS filler metal specifications. Other filler metals may be used as long as the applicable welding procedures are qualified.

Table 1, in Section 5 on pages 1 5-1 6, divides filler metals into nine groups, based on electrode characteristics and the welding processes that use them. It is important to note that the Group Numbers that API 1104 uses are different than the F-Numbers that AWS uses to group filler metals. For instance, the low-hydrogen SMAW electrodes are F-No. 4 electrodes as defined by AWS, but they are Group No. 3 electrodes in API 1104. Table 1 lists:

(a) Group Numbers for filler metals, electrodes, and fluxes.
(b) AWS Specifications.
(c) AWS Classifications for filler metals and electrodes.
(d) AWS Classifications for fluxes.

Group Nos. 1, 2, and 3 electrodes are for SMAW. Group No. 4 electrodes and fluxes are for SAW. Group No. 5 electrodes are for GMAW, GTAW, and PAW. Group No. 6 electrodes are for OFW and Group Nos. 7, 8, and 9 are for FCAW.

Be attentive to the footnotes in Table 1, which modify the requirements for use of certain electrodes, filler metals, or fluxes and may give additional rules.

Paragraph 4.2.2.2 requires protection of filler metals and fluxes from deterioration and excessive changes in moisture, although no definition of “excessive” is provided. Obviously, if the flux coating on a SMAW electrode is damaged, it should not be used because it will not operate properly. Low hydrogen SMAW electrodes (AWS classifications which end in 5, 6, or 8) must be stored in such a way that their coatings do not absorb excessive moisture from the atmosphere prior to use for welding.

Although it is not specifically required by API 1104, there are recommended good manufacturing practices for the storage and use of low-hydrogen SMAW electrodes in applicable AWS filler metal specifications. These include

(a) The storage of these electrodes in a heated, vented oven at a prescribed temperature after removal from their hermetically sealed containers,

(b) Limited exposure to the atmosphere, and

(c) Recommended minimum baking times and temperatures after atmospheric exposure.

Paragraph 4.2.3.1 addresses the various types of shielding gases used for welding. Inert shielding gases do not react chemically with the weld pool; they work by simply shielding the weld pool from interacting with the gases in the atmosphere. An active gas, however, does interact with either the arc, the weld pool, or in some cases, both. Inert gases include argon and helium. Active gases include carbon dioxide and oxygen. In GMAW, sometimes mixtures of inert and active shielding gases are used.

Gases must be relatively pure and dry and the shielding gas or gases to be used shall be qualified in accordance with the applicable essential variable rules for procedure qualification. API 1104 does not reference AWS A5.32 for purity requirements for shielding gases.

Paragraph 4.2.3.2 addresses storage and handling of gases for welding. Gases shall not be fled intermixed in their containers and gases of questionable purity or gases from damaged containers shall not be used.

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