CSWIP 3.1 Notes

1. Misunderstanding the questions and negative sentences

Most CSWIP questions are prepared with using the negative words such as not, unlikely, unsuitable, most. These questions may reduce our score if you are inadequately understood; it is one of important point which may cause of failure.

So, I recommend a best way to answer more questions and read carefully study book, and then summaries in chart of your understanding.

Below examples are listed some question related the negative sentences:

Q_1.1
Which of the following would be most unlikely to be found in a butt welded butt joint using conventional radiographic method of NDT?
Answer:
A “U” preparation, if any lack of sidewall fusion imperfection due to its indication may parallel with the beam.

Q_1.2
Which of the following defects is unlikely to be found by visual inspection?
Answer:
Linear misalignment, undercut, overlap: an external imperfection and can check during visual inspection,
Slag inclusion: may occur internal or external of deposited weld metal. The internal imperfections are detected by RT/UT method, surface/sub-surface shall be detected MT, PT/DPT only detect on surface imperfections.

Q_1.3

Which of the following would not be required to be checked before welding?
Answer: PWHT, weld reinforcement, NDT for weldment.

2. Lack of field/shop inspection and technical knowledge

The second cause are lack of field or shop inspection and technical knowledge. As you known there are some guy would like to get the CSWIP certificate but they were limit experience in field inspection, and are less experienced in testing such as conventional non-destructive test, destructive test, material review, material inspection, running PQR, welder qualification.

There are some questions may helpful you like:

• Organization and running PQR, development WPS and welder qualification.
• Prepare ITP, operations procedure. These scopes are not the duties of welding inspector, but not limit learning for you.
• Witnessing destructive test for material, welding consumable and procedure, how to verify test specimens?
• Interpretation of specification and acceptance criteria?
• Conventional NDT methods like VT, RT, UT, MT, PT test and its advantages, its disadvantages?
• PWHT procedure, and heat treatment for material, and weld,
• Review NDE report,
• Final documentations,

Q_2.1
Is it always necessary to preheat the base material before welding?
Answer: As per approval WPS (most)
In order test for welding consumable based on material specification for weld test assembly or manual instruction for hard-banding.

Q_2.2
All tensile test pieces most likely subject for purpose?
Answer:
Welding consumable verification.
Read more AWS A5.1 for set up test specimens for verification, a qualified procedure is not required.

I hope that you spend more times to figure out standards/ specifications before attending the training course.

Read more: Standard for welding inspector 57.

3. Update wrongly the draft answer to answer sheet

When the time is up of an allowed examination and Lecturer informed “ Stop! Time’s up! Pen down! ”. You will rush to transfer the draft answers to an answer sheet, that are leading to put a wrong answer.

If you are facing this situation, please do not worry and keep calm to fix it before submitting I hope that you need to control the timing examination as instructed by Lecturer and allow approximately 5 minutes to double check the draft answers with answer sheet.

CSWIP notes

The questions and answers based on the document no. WIS5-90516b - CSWIP 3.1 Welding Inspector. These question are separated by each section, it makes easy for reading and learning.

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Duties of Welding Inspector

Q_1.1: What is meant by the term duty cycle?
Answer: The amount of TIME a welding machine can be used.
Learn more: WIS5 Section 21.2.

Q_1.2: What is the recommended minimum range of illumination required by BS EN ISO 17637 for inspection of a welded surface?
Answer: 350 – 500 lux.
Learn more: WIS5 Section 1.1.3 and BS EN ISO 17637.

Q_1.3: A magnifying lens should be used during visual inspection as BS EN ISO 17637:
Answer: x2 to x5 times.
Learn more: WIS5 Section 1.1.4 and BS EN ISO 17637.

Q_1.4: Who should have access to the WPQRs?
Answer: Welding engineer.
Learn more: CSWIP document WI-6-92.

Q_1.5: Who should have access to the WPS?
Answer: Welding inspector and welder for working site.

Q_1.6: Who has the final responsibility of sentencing and accepting a weld on completion?
Answer: Client or certifying authority.
Learn more: CSWIP document WI-6-92 for responsibilities.

Q_1.7: Which of the following would not be required to be checked before welding?
Answer: PWHT, hardness test, tensile test.
Learn more: WIS5 Section 1.1.6.

Q_1.8: Is it permissible to allow welding to be carried out in bad weather?
Answer: Yes, if adequate protection from the poor weather conditions, ensure weather conditions are suitable/comply with Code.
Learn more: WIS5 Section 1.1.6.

Q_1.9: What course of action should be taken upon finding a welder using incorrect welding consumables, un-approval drawing, incorrectly WPS?
Answer: Report, record all related information, and seeking high authority.

Q_1.10: Who should select the specific welds for NDT, to cover the 10% contractual percentage required by the Specification/Code?
Answer: Engineering design or an approval ITP, project specification.

Term and Definitions

Note: “Term and Definitions” details in the study book accordance to BS 499-1.

• Joint: A connection where the individual components, suitably prepared and assembled, are joined by welding or brazing.
• Weld: A union of pieces of metal made by welding.
• Welding: An operation in which two or more parts are united by means of heat, pressure or both, in such a way that there is continuity in the nature of the metal between these parts.
• Homogeneous joint: welded joint in which the weld metal and parent metal have no significant differences in mechanical properties and/or chemical composition.
• Heterogeneous joint: welded joints in which the weld metal and parent materials have significant differences in mechanical properties and/or chemical composition.
• Dissimilar material joint: welded joint in which the parent materials have significants
• Autogenous weld: A fusion weld made without filler metal by TIG, plasma, electron beam, laser or oxy-fuel gas welding. Any additional filler metal or without filler metal become an essential variable in welding procedure.
• Features of the completed weld: learn more WIS5 Section 2.3, don’t confuse these definitions.
  
• Actual throat thickness = design throat thickness + excessive weld metal thickness of root and cap (other name is reinforcement)
• HAZ : higher hardness, high strength, low toughness, large changes microstructure.

Features of the weld preparation: learn more WIS5 Section 2.4.

Welding position: learn more WIS5 Section 2.7.

• ISO 6947 - Welding and allied processes. Welding positions.

• ASME IX may easy understanding and find out at Figure QW-461. Based on joint preparation and member being joined, we have different positions for qualification.

Question: Compound weld or groove weld?

• Don’t confuse between US standard with European standards definitions.
• Acc. to US standard: double groove weld and fillet weld.*
• Acc. to EU standard: Double bevel compound of butt and fillet weld.*

Questions and answers
Below guidance to answer the questions and cross-reference to study book.

Q_2.1: A fillet weld has a design throat thickness of 8mm. That is the minimum leg length that is required?
Answer: leg length z = 8/0.7 = 11.4mm. It is an easy question with the math formula.
Learn more: WIS5 Section 2.6.

Q_2.2: When visually inspecting a fillet weld, it would normally be “sized” by
Answer: The leg lengths
Note: we can’t measure the DESIGN THROAT THICKNESS that is only reference for visual inspection.

Q_2.3: The strength of a fillet weld is primary controlled by:
Answer: Design throat thickness.
Learn more: WIS5 Section 2.6.1.

Q_2.4: An effective weld metal volume reduction can be achieved by weld preparation?
Answer: change from V to U, V to double V and also reduce distortion, shrinkage.
Best way to find out by calculating areas of each type preparation.

Q_2.5: Which weld preparations are susceptible to lack of side wall fusion?
Answer: U and J preparation.
Learn more: WIS5 Section 2.4.1- Angle of bevel.

Q_2.6: The increase in bevel angle may result:
Answer: more deposit weld metal and distortion.

Q_2.7: Effective throat thickness?
Answer: The minimum dimension of throat thickness used for design purposes.

Q_2.8: Compound welds:
Answer: Combinations between two different weld types.
Learn more: WIS5 Section 2.6.3.

Welding Imperfections

This article is important for theory exams and practical exams. Read more Welding imperfections and welding defects.

Q_3.1: Which of the following types of imperfection is generally considered to be the most serious?
Answer: crack, planar.
Note: Most project specifications are prohibited any cracking, regardless of size or location.
Lear more: WIS5 Section 3.2 or ASME B31.1, ASME B31.3, AWS D1.1.

Q_3.2: The planar defects.
Answer: crack, lack of fusion, incomplete penetration etc.
Learn more: ASME B31.3 Table 341.3.2 for symbol “A”.

Q_3.3: Which of these statements are true concerning “lamellar tearing”?
Answer: Occur on base metal only.
Learn more: WIS5 Section 3.2.2 , 17.5

Q_3.4: A metallurgical problem most associated with submerged arc welding?
Answer: Solidification cracking in the weld metal

Q_3.5: When visually inspecting the root bead of a single V-butt weld it should be checked?
Answer: Lack of root penetration.

Q_3.6: Which indication appears in a radiograph as a dark area with well-defined, straight edges at the center of the weldment.
Answer: Incomplete penetration.

Q_3.7: Lack of sidewall fusion
Answer: Is the most susceptible in a “U-preparation”

Q_3.8: A very fine straight dark line running along ONE EDGE of the lighter image of the root penetration bead in RT film?
Answer: Lack of root fusion.

Q_3.9: Burn through may occur because the:
Answer: Current is too high, insufficient travel speed, etc.
Lear more: WIS5 Section 3.6.10 and indications in the RT film.

Q_3.10: Slag inclusion would not occur with welding process?
Answer: GTAW or TIG, MIG welding processes.

Q_.3.11: Which welding processes will produce slag inclusion?
Answer: MMA, FCAW, SAW.

Q_3.12: Heavy porosity on the surface of some MMA welds made on a construction site is
most likely to be caused by:
Answer: Moisture pick-up in the electrode covering.

Q_3.13: On inspecting a completed weld which has Charpy impact requirements some small areas of undercut have been found. The welder says he can quickly put this right by depositing a thin narrow bead along the undercut. In this situation would you?
Answer: Only allow the welder to cosmetically blend out the undercut
Note: local spot weld made hardening surface, so, a best way a slight blend out of sharp corner to smooth transition to base metal.

Q_3.14: Undercut normally assessed by?
Answer: its depth, length, sharpness.

Q_3.15: Which of the following would be cause for rejection by most fabrication standards
when inspecting fillet welds with undercut, a small amount of width, length, depth and sharpness?
Answer: Sharpness.

Q_3.16: Which of the following actions can help to prevent the production of spatter during a welding process.
Answer: Switch to AC power, use dry electrodes and reduce arc current.

Destructive test

Q_4.1: Mechanical tests are divided into two areas of ?
Answer: Qualitative and quantitative
Learn more: WIS5 Section 4.

Q_4.2: Which mechanical test can be used to make an assessment of surfacing breaking defects?
Answer: bend test, fracture test, macro test are called QUALITATIVE TEST to access the joint quality.
Lear more: WIS5 Section 4.

Q_4.3: Which mechanical test can be used to make an assessment of mechanical properties or QUANTITATIVE TEST?
Answer: impact test, hardness test and tension test are called quantitative test to access the mechanical properties.
Lear more: WIS5 Section 4.

Q_4.4: A transverse tensile test piece from a weld joint will give the:
Answer: Tensile strength of the JOINT.
Lear more: WIS5 Section 4.1.1.

Q_4.5: What is the purpose of a tensile test?
Answer: Tensile strength, ductility (elongation), yield strength.
Lear more: WIS5 Section 4.1

Q_4.6: During a transverse tensile test, the FIRST STAGE the specimen goes through is known as:
Answer: Elastic stage.
Lear more: WIS5 Section 4.1 Figure 4.4.

Q_4.7: When a metal returns TO ITS ORIGINAL SHAPE after an applied load has been removed, the metal is said to have:
Answer: Elasticity.
Lear more: WIS5 Section 4.1 Figure 4.4.

Q_4.8: When a metal was not return to its original shape after an applied load has been removed, the metal is said to have:
Answer: Plasticity.
Lear more: WIS5 Section 4.1 Figure 4.4.

Q_4.9: In a transverse WELD tensile test, if the break was in the parent material, the sample would be:
Answer: Acceptable if the UTS is equal to or greater than the specified UTS of the product (BS EN ISO) or not less than 95% of the specified UTS of the base metal (ASME BPVC IX).
Learn more: ASME BPVC IX QW-153 or BS EN ISO 15614 Part 1 Section 7.4.

Q_4.10: In a CVN test, a brittle material would be indicated if the fracture surface?
Answer: Flat and featureless (brittle fracture show no lateral expansion).
Lear more: WIS5 Section 4.1.3 and ASME A370
Addition: if welding procedure qualification for stainless steel must record a lateral expansion of CVN test as ASME B31.3 table 323.3.5.

Q_4.11: In welder qualification testing of 13 mm plates, why are side bends used instead of root and face bends:
Answer: They give more accurate indications.
Lear more: WIS5 Section 4.1.6 and ASME A370.

Q_4.12: Which is the best destructive test for showing lack of sidewall fusion in a 20 mm thickness butt weld?
Answer: Side bend.
Lear more: WIS5 Section 4.1.6 and ASME A370.
Note: Root bend (root in tension, face in compression); face bend (face in tension, root in compression), side bend (side in tension).

Q_4.13: Which of the following types of destructive test is used for welder qualification:
Answer: Fracture test.
Learn more: WIS5 Section 4.1.7.

Q_4.14: Charpy impact tests (CVN) show a 50% rough torn surface and a 50% flat crystalline surface after the completed test, this would indicate which type of failure?
Answer: Ductile to brittle.

Q_4.15: Charpy impact test showing a flat through surface after the completed test, this would indicate which type of fracture?
Answer: Brittle fracture.

Q_4.16: A fatigue failure characteristic by the appearance of the fracture surface.
Answer: Smooth

Q_4.17: Hardness methods are normally used for survey welding procedure qualification?
Answer: Vickers or Rockwell method.
Learn more: WIS5 Section 4.1.4 or NACE MR0175 part 2, para. 7.3

Non-Destructive test

Q_5.1: What is the greatest disadvantage of radiographic inspection?
Answer: The harmful effects of ionizing radiation.

Q_5.2: The usual method of assessing the sensitivity of radiograph is by means of a:
Answer: IQI ( Penetrameter). Don’t confuse with dosimeter.

Q_5.3: Se75 and Ir192?
Answer: Se75 produces a good quality radiographs than Ir 192.
Learn more: WIS5 Section 5.2.

Q_5.4: If we start with 50 curies of Co60, what will the activity be at the end of 15.9 year?
Answer: 6.25 Curies = 50/(2^3) (half life of Co 60 is 5.3 years x 3 times = 15.9 years).

Q_5.5: The half-life of an isotope is dependent of?
Answer: Isotope type (not depend on time of exposure, size of isotope)
If it is necessary to radiograph a 70mm thickness of plate, which gamma source would likely to used?
Answer: Co 60.

Q_5.6: Which of the defects would not be expected in a weld made by the MIG/MAG welding process (solid wire)?
Answer: Slag inclusion.

Q_5.7: Which of the following methods of NDT would be most likely to detect lack of side fusion in ferritic steel welds?
Answer: UT (most likely)

Q_5.8: Which NDT method is associated with the use of a yoke?
Answer: MT / MPI

Q_5.9: Which NDT method is associated with Burmah Castrol strips?
Answer: MT

Q_5.10: With which of the following NDE processes is it possible to detect both surface and slight sub-surface defects up to 2mm below the surface:
Answer: MT using DC power source

Q_5.11: Disadvantage of MPI using the prods method.
Answer: It may cause arc damage on the specimen material surface

Q_5.12: With the DPI method of inspection, after the contact time has elapsed the dye should be removed by:
Answer: Wipe clean, using a lint free cloth soaked in a solvent remover.

WPS and Welder Qualification

The questions and answers based on the document no. WIS5-90516b - CSWIP 3.1 Welding Inspector. These question are separated by each section, it makes easy for reading and learning.

Q_6.1: Is it permissible to allow a trainee welder to carry out production welding?
Answer: No, welder qualification is required.

Q_6.2: How are the length of tack welds during assembly and fit-up determined?
Answer: The project specification or code application, or specified in the WPS.

Q_6.3: Is it always necessary to preheat the base material before welding?
Answer: Specific in the WPS.

Q_6.4: If any changes in essential variable may:
Answer: Change the properties of the weld, requalification is required

Q_6.5: You notice the welders are adjusting the current on the welding set, is the allowable?
Answer: Yes, within range of WPS qualification

Q_6.6: Which of the following destructive tests is not normally required for welder approval test for mild steel?
Answer: tensile test, impact test

Q_6.7: Which group of welders is most likely to require continuous monitoring by a welding inspector?
Answer: Overland pipeline welders

Q_6.8: The majority of welder qualification tests are carried out using un-backed joints, because:
Answer: It requires more skill and increases the welders’ qualification range.

Material Inspection

Q_7.1: Which of the following alloying elements is used mainly to improve the toughness of steels?
Answer: Manganese.
Learn more: WIS5 Section 7.3
Note: please note for % Carbon, Silicon, Chromium, Nickel, Sulphur, Phosphorus, and its advantage, its disadvantage related to welding imperfections.

Q_7.2: Which of the chemical elements has the greater effect on the harden ability of a steel plate?
Answer: Carbon.
Learn more: HAZ grain size and its effective.

Q_7.3: Which defect would you expect to obtain in TIG welds in non-deoxidized steel?
Answer: Porosity, due to non-deoxidized steel does not killed steel.

Q_7.4: What constituent is needed in coating of electrode of an electrode to prevent formation of porosity in welding of rimming steel?
Answer: Silicon.

Q_7.5: In a steel, which has improved creep properties at elevated temperature, which one of the following elements helps in this improvement?
Answer: Molybdenum.

Codes and Standards

A best way to remember the standards that read more specifications.

Q_8.1:Which European standard is used for the basic requirements for visual inspection?
Answer: BS EN ISO 17637

Q_8.2: Which standard is used for European welding procedure qualifications?
Answer: BS EN ISO 15614

Welding symbol and definitions
• BS EN ISO 2553
• BS 499-1
• AWS A2.4; A3.0

Guide for visual examination and welding imperfections
• BS EN ISO 17637
• BS EN ISO 6520-1
• AWS B1.10

Weldability
• EN 1011 part 2
• ISO 13916

Material and welding consumables
• BS EN 10025 part 1
• BS EN 10204
• ASME BPVC Section II part A, popular material SA-36, 105, 106, 182, 234, 403, 516
• ASME BPVC Section II part C, popular welding rode SFA 5.1, 5.9, 5.17, 5.18, 5.20

Welding procedure and welder qualification
• BS EN ISO 15614 part 1
• BS EN ISO 9606-1
• ASME BPVC Section IX
• AWS D1.1
• API standard 1104

Destructive test
• BS EN ISO 9016 - Impact test
• BS EN ISO 4136 - Transverse tensile test
• BS EN ISO 5173 + A1 - Bend test
• BS EN ISO 17639 - Macro test
• ASTM A370 - Mechanical Testing of Steel Products
• NACE MR0175 or ISO 15156 - Hardness survey

Non-Destructive test
• ASME BPVC Section V for 5 conventional method: RT, UT, MT, PT, VT
• ASME B31.1 & B31.3 for acceptance criteria of weld
• AWS D1.1 for acceptance criteria of weld
• API standard 1104 for acceptance criteria of weld

Heat treatment and PWHT
• Stress-relief depends on code application, services of material application, engineering design such as ASME BPVC VIII, ASME B31.1/B31.3, AWS D1.1.
• Heat treatment for material and its delivery condition like normalizing (ASTM A106 Grade B), hot-rolled (BS EN 10025-2 grade S355J2), or Solution heat treated (ASTM A312 Type 316/316L).

Read more standards for welding inspector.

Welding symbol

Q_9.1: A drawing with symbols to BS EN ISO 2553 will show a 5mm leg fillet weld?
Answer: Z
Learn more: WIS5 Section 2.6, 9.9.1 and BS EN ISO 2553

Q_9.2: According to BS EN ISO 2553 - symbolic representation on drawings, if the symbol is on the identification line, where does the weld go?
Answer: Opposite arrow side

Q_9.3: The number 111 is shown at the tall-end of a weld symbol reference line. According to BS EN ISO 2553.
Answer: MMA
Note: US standards is SMAW, please check properly question, don’t pick wrong the answer.
Learn more: WIS5 Section 9.11 and BS EN ISO 2553

Q_9.4: According to AWS A2.4, where does the symbol go for welding on the arrow side?
Answer: below reference line
Learn more: WIS5 Section 9.12 and AWS A2.4

Q_9.5: According to AWS 2.4 a weld symbol for the other side is placed:
Answer: Above reference/continuous line.

Q_9.6: Making a symbol for a symmetrical fillet weld accordance with BS EN ISO 2553
Answer: Dashed line is not required
Learn more: WIS5 Section 9.9.2

Instruction to welding process

Q_10.1: Weldments in carbon-manganese steels, made by low heat input welding may shown
Answer: Higher hardness

Please note Heat Input formula, it is very important to you because of more questions relevant to heat input, units and covert its units, thermal efficiency factors
Heat Input (kJ/mm)= V x A / (TS x1000)
TS or ROL: Travel speed (mm/ sec) or other name is Run Out Length (mm/sec.)

Example: A butt weld has been made by MMA in a 50mm thick impact tested steel plate. The welding electrode use was a basic type, 5mm diameter. The measured welding parameters for one of the runs was 250 amps, 24 volts, using DC+ve polarity, and a ROL of 180mm per min. What would be the Arc energy?
Learn more: WIS5 Section 10.3

Q_10.2: Weldment in carbon-manganese steels, made using a heat input higher than the maximum specified by the WPS.
Answer: Lower toughness and larger grain size.
High heat input means decrease travel speed, increase V &A. manual GTAW process is made with lower heat input.

Q_10.3: A WPS may specify a maximum width for individual weld beads (weave width) when welding C-Mn steels. If the width is exceeded it may cause:
Answer: Exceed weld bead > lower travel speed > high heat input > a reduction in HAZ toughness or larger grain size.

Q_10.4:Which of the following units is used to express heat input?
Answer: Lets check Heat Input formular HI=A x V/TS > SI Unit is (J/mm).

Q_10.5: The term manual welding is often used when the welder controls.
Answer: Arc length.

Q_10.6: Which process uses a constant current/ drooping characteristic?
Answer: MMA, TIG are manual welding process.
Learn more: WIS5 Section 10.5

Q_10.7: Which process uses a constant voltage / flat characteristic?
Answer: GMAW, MIG/MAG, SAW are an auto welding process.
Learn more: WIS5 Section 10.5.

Q_10.8: Which welding process develops the lowest level of hydrogen.
Answer: GTAW or MIG/MAG using a bare electrode.
Note: SMAW, SAW using flux cover, may need to bake before using (except flux cored wire).

Q_10.9: Which of the following welding processes uses a resistive heating system to achieve weld metal deposition?
Answer: Resistance spot welding.

Q_10.10: How could arc blow be avoided?
Answer: Use AC.

Q_10.11: When MMA welding what will be the effect on the weld if the electrode was changed from DC+ve to AC.
Answer: it would give less penetration.

Q_10.12: Which of the following defects is more common to weld deposited by the auto welding process than weld deposited by manual welding?
Answer: Lack of side fusion because of oscillation/travel speed control by machine. So, fit-up inspection is very important.

Q_10.13: Measurement voltage
Answer: Should measure voltage as close to the welding arc as possible.

MMA welding process

Q_11.1: Which type of electrode is used for stovepipe welding for overland pipeline construction?
Answer: Cellulosic or cellulosic-iron powder coated electrodes

Q_11.2: You notice that MMA electrodes with the flux covering removed are being used as filler rods for TIG welding. This should not be allowed because:
Answer: The weld metal composition may be wrong.

Q_11.3: For a given voltage and current settings on a MMA welding plant, when the arc length is shortened, which of the following will be most affected?
Answer: The voltage will decrease, manual process controlled by arc volt.

GTAW / TIG welding process

Q_12.1: Which polarity is normally used for GTAW welding of aluminum?
Answer: AC
Most materials welded by GTAW require DC EN, but aluminum is very difficult to weld. Aluminum is often welded using alternating current (AC). I am not experience in aluminum welding process, please learn more TWI Job Knowledge 6 or welding consumable data sheet / its certificates.

Q_12.2: When considering the tungsten arc welding process what is the purpose of the down-slope (slope-out) control?
Answer: To help prevent the formation of crater pipe and possible cracking.
Note: It is normally find in at the end of weld pass, after switch off arc. You can see clearly on PT method for stainless steel.

SAW welding process

Q_14.1: Increasing the arc voltage with constant current and travel speed will?
Answer: Produce a flatter, wider bead, and increase flux consumption.

Q_14.2 Which power source characteristic if increase current greater than 1000 amps
Answer: Drooping/constant current

Q_14.3: Fused Fluxes
Answer: No need to bake and cannot make basic fused flux.

Q_14.4: Why install the run out/run off plate at both of weld joint?
Answer: Eliminate welding imperfection at starting arc and finishing arc.

Welding consumables

Q_16.1: Manual metal arc electrodes can be grouped into three main types.
Answer: Basic, cellulosic and rutile

Q_16.2: The chemical composition of the weld metal deposited by a C-Mn steel MMA
electrode is usually controlled by:
Answer: Additions in the flux coating.

Q_16.3: An SMAW electrode which is classified as an E6013 (according to AWS A5.1 or A5.5 ) mean?
Answer: Rutile type

An AWS A5.1/5.1M or ASME SFA 5.1/5.1M Table 1 “Electrode Classification”. Designation E4313 uses SI Units, designation E6013 uses U.S. Customary Units.

• E: expressed Electrode
• 60: expressed Tensile strength (PSI)
• 1: expressed All Position
• 3: High titania potassium consistent, Rutile type

Note:
Cellulose type, end in 0, 1: E6010, E6011, E7010, E8011,
Rutile type, end in 2, 3, 4: E6012, E6013, E6014,
Basic type, end in 5, 6, 8: E7015, E7016, E7018

Learn more: WIS5 Section 16.2
Learn more: EN ISO 2560 A E4321 and EN ISO 2560 B E5516

Method A: EN ISO 2560 A E4321
• 43: expressed minimum yield strength and impact absorbed 47J

Method A: EN ISO 2560 B E5516
• 55: expressed minimum tensile strength and impact absorbed 27J

Q_16.4: Basic electrodes are often sold vacuum packed. The reason is:
Answer: They have been packed at the manufactures at a hydrogen level less than 5ml per 100g of weld metal deposited.

Q_16.5: A typical baking temperature for basic low hydrogen electrodes is:
Answer: 350 deg. C for 1 hour (min.) and then drying at 120 – 150 deg. C
Learn more: WIS5 Section 16.3

Q_16.6: Silicon is added to steel and the covering of MMA electrodes to:
Answer: Provide deoxidation.

Q_16.7: Manual metal arc welding of low alloy steels is more likely to be performed with
Answer: Basic hydrogen controlled electrodes

Q_16.8: Which electrode types of basic, rutile, cellulose would produces the lowest levels of hydrogen?
Answer: Basic coated electrodes when baked correctly immediately prior to use

Q_16.9: The weld metal deposits of manual metal arc electrode achieves its mechanical strength through?
Answer: The flux coating, because of metal core is a rimming steel

Q_16.10: Submerged arc fluxes can be supplied in two forms; these are?
Answer: Fused and agglomerated

Q_16.11: The type of SAW flux is more resistance to moisture absorption:
Answer: Fused

Weldability of steel

Q_17.1: Using a stabilized stainless steel will reduce the risk of?
Answer: Weld decay
Learn more: WIS5 Section 17.6

Q_17.2: A long centerline crack has been detected in a submerged arc weld bead this may be due to
Answer: Weld bead is deep and narrow.
Learn more: WIS5 Section 17.4

Q_17.3: A steel designated as “Z” quality will have:
Answer: Through-thickness ductility values > 20%
Learn more: WIS5 Section 17.5.3 (reference) and material specification

Q_17.4: Which material is pre-heating most likely to be required?
Answer: most high strength alloy steels (HSAL) is required pre-heat before welding either than low carbon steel, mid-steel or austenitic stainless steel. Heat treatment may be applied to reduce stress after welding.

Q_17.5: In the welding of austenitic pipe work, main purpose of purging argon?
Answer: Prevent oxidation of the rood bead

Q_17.6: In the welding of Austenitic stainless steels, the electrode and plate material can be purchased with LOW carbon contents. The reason for this is to prevent?
Answer: The formation of chromium carbides.

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