Welding glossary from A to Z

In welding technology a misunderstood word quickly turns into a rejected weld or a discussion with the notified body. This glossary gives the meaning of each term as the standard defines it, explained in plain language, with a reference to the standard it comes from.

Term not listed, or want to know how it applies to your situation? Ask the Welding & Quality Assistant or call +31 6 29 72 37 91.

A

Acceptance criterionISO 5817, ISO 11666

The predefined limit beyond which a measured value or detected indication is no longer acceptable. Without a defined criterion an inspection result cannot be judged.Read more: How to write an ITP that works in practice

Arc blow

Deflection of the arc by magnetic fields in the workpiece, often caused by residual magnetism or a poorly placed earth clamp. It leads to irregular penetration and lack of fusion.Read more: Magnetic particle testing (MT) of welded joints

Arc voltage

The voltage across the arc during welding, in volts. Together with current and travel speed it determines heat input. Higher voltage gives a wider, flatter bead with less penetration.Read more: Calculating and controlling heat input

Austenite

The face centred cubic phase of iron, stable in carbon steel above roughly 727 degrees Celsius and, in sufficiently alloyed stainless steel, also at room temperature. Austenite is tough, non-magnetic and not hardenable.Read more: Welding austenitic stainless steel: 304 and 316

B

Back step welding

A technique in which short lengths are welded opposite to the direction of progression. It reduces net shrinkage and therefore distortion on long seams.Read more: Controlling weld distortion: causes, types and measures, Planning the welding sequence

Backing gasISO 14175

The gas used to purge the root side of a weld to prevent oxidation, usually argon or a nitrogen hydrogen mixture. Residual oxygen is measured rather than estimated.Read more: Welding austenitic stainless steel: 304 and 316, Food and pharmaceutical

Butt weldISO 2553

A weld between two parts lying in the same plane, with or without joint preparation. With full penetration the joint transfers the full plate strength.Read more: Full penetration: when required and how to prove it

C

CE markingEN 1090-1

The marking by which a manufacturer declares that a construction product complies with the harmonised European standard. For load bearing steel structures it requires a certified FPC system to EN 1090-1.Read more: CE marking of steel structures under EN 1090-1

CET carbon equivalentEN 1011-2

A carbon equivalent expressing a steel's susceptibility to cold cracking, used in the preheat calculation of EN 1011-2. CET weights manganese and molybdenum more heavily than the older CEV formula.Read more: Preheating in welding: when is it required

CEV carbon equivalentEN 1011-2

The carbon equivalent to the IIW formula, used to estimate weldability and cold cracking risk of steel. It appears on the material certificate and is an input for the preheat calculation.Read more: Preheating in welding: when is it required, Material certificates 3.1 and 3.2 to EN 10204

Cold crackEN 1011-2

A crack forming hours to days after welding through the combination of hydrogen, a hard structure and tensile stress. Also called hydrogen cracking or delayed cracking.Read more: Preventing hydrogen cracking: mechanism and measures

Combined thicknessEN 1011-2

The sum of the material thicknesses meeting in a joint, measured at a fixed distance from the weld. An input for the preheat calculation, because it determines how quickly heat is conducted away.Read more: Preheating in welding: when is it required

Concession

Written approval to use a product that does not fully meet the specification. It may only be granted by the party that set the requirement and is recorded in the dossier.Read more: The NCR: recording, resolving and learning from non-conformities

Cooling time t8/5EN 1011-2

The time in which the weld cools from 800 to 500 degrees Celsius. It links heat input, thickness and preheat to the resulting microstructure and is therefore the key quantity in EN 1011-2.Read more: Calculating and controlling heat input, Welding fine grain steel: S460 to S690

Covered electrode (111)ISO 4063, ISO 2560

Manual arc welding with a consumable covered electrode. Process 111 to ISO 4063. Insensitive to wind and therefore suited to site work; requires dry storage because of hydrogen.Read more: Preventing hydrogen cracking: mechanism and measures

Cruciform joint

A joint where a plate is welded perpendicularly between two others. Loaded perpendicular to the rolling direction, making it a classic situation for lamellar tearing and a critical fatigue detail.Read more: Fatigue of welded joints

CTODBS 7448, ISO 15653

Crack Tip Opening Displacement: a fracture mechanics test measuring the critical opening at a crack tip. Required for offshore work, heavy sections and low design temperatures.Read more: Offshore and marine

CWIAWS QC1, ISO 14731

Certified Welding Inspector to AWS QC1: the American qualification for welding inspectors. The European counterpart is the IWI under the IIW scheme, with levels B, S and C.Read more: CWI vs IWI: welding inspector certification compared

D

DAC curveISO 17640

Distance Amplitude Correction: a sensitivity curve in ultrasonic testing correcting for the fact that an identical flaw at greater depth returns a weaker echo. Without DAC or DGS an echo height has no meaning.Read more: Ultrasonic testing (UT) of welded joints

Delta ferriteISO 8249, DIN EN 1600

A small amount of ferrite in austenitic weld metal, typically 3 to 10 FN, which prevents hot cracking during solidification. Too little risks cracking, too much costs toughness and corrosion resistance.Read more: Ferrite measurement in stainless and duplex weld metal, Welding austenitic stainless steel: 304 and 316

Dilution

The extent to which parent material mixes with the weld metal, expressed as a percentage. On corrosion resistant overlays, dilution lowers the alloy content and therefore the corrosion resistance of the layer.Read more: Welding nickel alloys and Inconel, Dissimilar metal welds: stainless to carbon steel

Duplex stainless steelISO 17781

Stainless steel with roughly equal parts austenite and ferrite. It combines high strength with good chloride corrosion resistance but demands strict heat input control to preserve the phase balance.Read more: Welding duplex stainless steel: key considerations

E

EN 10204EN 10204

The standard for inspection documents on metallic products. Type 2.2 is a test report, 3.1 an inspection certificate issued by the manufacturer and 3.2 one countersigned by an independent party.Read more: Material certificates 3.1 and 3.2 to EN 10204

EN 1090EN 1090-1, -2, -3

The European standard for the execution of steel and aluminium structures. Part 1 covers conformity assessment and CE marking, part 2 the technical requirements for steel, part 3 those for aluminium.Read more: Execution classes under EN 1090-2: EXC1 to EXC4 explained, EN 1090 support: from execution class to CE marking

Essential variableISO 15614-1, ASME IX

A parameter whose change beyond the permitted range invalidates the qualification, such as material group, process, thickness, position or heat treatment. A change requires new or supplementary qualification.Read more: Essential variables: what invalidates a qualification

Excess penetrationISO 5817 nr. 504

Weld metal protruding too far on the root side. In piping it obstructs flow and in hygienic applications it makes the weld impossible to clean.Read more: Food and pharmaceutical

Execution class (EXC)EN 1090-2

A four level classification, EXC1 to EXC4, which in EN 1090-2 sets the severity of all execution requirements: weld quality level, NDT extent, tolerances and traceability. Where unspecified, EXC2 applies.Read more: Execution classes under EN 1090-2: EXC1 to EXC4 explained

F

Factory Acceptance Test

The inspection at the manufacturer where the client establishes compliance before shipment. It typically covers document review, dimensional checks, functional testing and assessment of the final dossier.Read more: FAT and final inspection without surprises

Factory Production ControlEN 1090-1

The documented system by which a manufacturer demonstrates that production is controlled and the product matches the specification. A prerequisite for CE marking under EN 1090-1.Read more: Factory production control (FPC) under EN 1090-1

FatigueEN 1993-1-9, EN 13001

Crack growth under repeated loading at stresses far below yield. In welded joints it is not the strength of the weld metal but the geometry of the weld toe that determines life.Read more: Fatigue of welded joints

FerritescopeISO 8249, ASTM E562

An instrument that determines ferrite content in austenitic or duplex weld metal by magnetic induction, expressed in FN or volume percent. It must be used on a smooth, clean weld.Read more: Ferrite measurement in stainless and duplex weld metal

Fillet weldISO 2553

A weld in the corner between two intersecting surfaces, with a triangular cross section. Strength is governed by the throat thickness; penetration into the root is generally not required.Read more: Calculating the throat thickness of a fillet weld

Flux cored wire (136)ISO 4063, ISO 17632

A tubular wire filled with flux, welded under shielding gas. It gives a higher deposition rate than solid wire and better positional weldability, with slag that must be removed.

Full penetration weldISO 5817, EN 1993-1-8

A joint in which weld metal is fused over the full material thickness. Structurally the strongest joint and required wherever the full plate strength must be transferred.Read more: Full penetration: when required and how to prove it

Fusion lineISO 9015-1

The boundary between molten weld metal and unmelted parent material. Immediately beside it lies the coarse grained zone, where hardness surveys expect the highest reading.Read more: Hardness testing of welded joints

H

Heat affected zone (HAZ)

The zone in the parent material beside the weld that has not melted but whose structure and properties have been altered by the welding heat. Often the weakest or hardest part of the joint.Read more: Calculating and controlling heat input, Hardness testing of welded joints

Heat inputEN 1011-1

The energy per unit length of weld, in kJ/mm, calculated from voltage, current, travel speed and the process efficiency factor. It governs cooling rate and therefore the resulting properties.Read more: Calculating and controlling heat input

Heat tintAWS D18.2, ISO 17781

The discolouration formed on stainless steel beside and on a weld through oxidation at elevated temperature. The colour runs from straw through blue to grey black and indicates how chromium depleted the oxide layer has become.Read more: Heat tint on stainless welds: pickling and passivation

Hold point

A point in the process where work may not continue until the designated party has released it. Unlike a witness point, where work may proceed.Read more: How to write an ITP that works in practice, Fabrication inspection at your supplier

Hot crackISO 6520-1 nr. 1001

A crack forming during solidification of the weld metal, when remaining liquid between the grains is pulled apart. Promoted by sulphur, phosphorus and an unfavourable solidification range.Read more: Welding nickel alloys and Inconel

I

Image quality indicator (IQI)ISO 19232

A calibrated wire or hole indicator placed on the component during radiography. Visibility of a specified wire proves the exposure achieved sufficient sensitivity.Read more: Image quality in radiography: ISO 19232, Radiographic testing (RT) of welded joints

Impact energyISO 148-1

The energy in joules absorbed by a notched specimen at fracture in a Charpy pendulum test. A measure of toughness at a given temperature and essential at low design temperatures.

Inspection and test plan

The document setting out, per production step, what is checked, by whom, against which standard, with which acceptance criterion and which record, including hold and witness points.Read more: How to write an ITP that works in practice

Interpass temperatureEN 1011-2, ISO 13916

The temperature of the workpiece immediately before the next run is deposited. A maximum protects against grain growth and property loss; a minimum coincides with the preheat temperature.Read more: Preheating in welding: when is it required

ISO 14731ISO 14731

The standard for welding coordination: the tasks and responsibilities of a welding coordinator and the knowledge level required. From EXC2 in EN 1090-2 a qualified welding coordinator is mandatory.Read more: The welding coordinator under ISO 14731: when, who and what, Hire a welding coordinator

ISO 15614ISO 15614-1, -2

The standard series for welding procedure qualification by procedure test. Part 1 covers steel and nickel, part 2 aluminium. It defines the test pieces, the testing and the range of qualification.Read more: ISO 15614-1: the welding procedure test explained, WPQR qualification to EN ISO 15614-1 and ASME IX

ISO 3834ISO 3834-1 t/m -6

The standard series for quality requirements in fusion welding, with three levels: comprehensive (part 2), standard (part 3) and elementary (part 4). It defines what a welding company must control, not how a weld should look.Read more: ISO 3834 parts 2, 3 and 4: which part fits your company

ISO 4063ISO 4063

The standard assigning a number to each welding process, such as 111 for covered electrode, 121 submerged arc, 135 MAG with solid wire, 136 flux cored and 141 TIG. Those numbers appear in every WPS.Read more: MAG welding process 135 and cored wire processes 136 and 138

ISO 5817ISO 5817

The standard setting limits for weld imperfections in steel, with quality levels B (stringent), C and D (moderate). The level follows from loading and consequences of failure, not from habit.Read more: ISO 5817 quality levels B, C and D: selecting and applying

ISO 9606ISO 9606-1 t/m -5

The standard for qualification of welders in manual and partly mechanised welding. It tests the skill of the person, in contrast to procedure qualification, which tests the procedure.Read more: Welder qualification to ISO 9606-1

ISO 9712ISO 9712

The standard for qualification and certification of NDT personnel, with level 1 for performing under supervision, level 2 for evaluating and reporting and level 3 for writing procedures.Read more: NDT personnel to ISO 9712: levels, responsibilities and validity

IWE, IWT, IWSISO 14731

International Welding Engineer, Technologist and Specialist: the three knowledge levels for welding coordinators under the IIW scheme. The required level follows from steel grade, thickness and execution class.Read more: The welding coordinator under ISO 14731: when, who and what, Hire a welding coordinator

J

Joint preparationISO 9692-1

The shape given to the parts to be joined: V, X, U, J or I, with included angle, root face and gap. The choice determines the volume of weld metal, the shrinkage and arc accessibility.Read more: Joint preparation: which form when

L

Lack of fusionISO 6520-1 nr. 401

Absence of fusion between weld metal and parent material or between adjacent runs. It is a planar defect and therefore structurally dangerous, and often hard to detect with radiography.Read more: Weld defects: recognition, causes and prevention, Ultrasonic testing (UT) of welded joints

Lamellar tearingEN 1011-2, EN 10164

A crack parallel to the plate surface, caused by shrinkage stress pulling perpendicular to the rolling direction on inclusion layers in the steel. Prevented with through thickness quality steel and adapted joint design.Read more: Full penetration: when required and how to prove it

Leg length (z)ISO 2553

The length of the triangle leg in the cross section of a fillet weld. For an equal leg fillet the throat is roughly 0.7 times the leg length; confusing the two is a common error.Read more: Calculating the throat thickness of a fillet weld

M

MAG welding (135)ISO 4063

Metal Active Gas: arc welding with a continuously fed solid wire under an active shielding gas. Process 135 to ISO 4063, the most widely used process in fabrication.Read more: MAG welding process 135 and cored wire processes 136 and 138

Manufacturing Record Book

The final dossier of a project: every document proving the product was made to specification, from material certificates and qualifications to NDT reports, heat treatment charts and non-conformities.Read more: The MRB and MDR: building the project dossier properly

Martensite

A hard, brittle structure formed when austenite cools too quickly to transform into ferrite and pearlite. In the HAZ of a weld, martensite is the direct cause of cold cracking.Read more: Hardness testing of welded joints, Preventing hydrogen cracking: mechanism and measures

Material groupISO/TR 15608

The classification of base materials to ISO/TR 15608 into groups with comparable welding behaviour, from group 1 for ordinary structural steel to group 8 for austenitic stainless and 21 and above for aluminium.Read more: How to determine whether an existing WPQR covers your application

N

NACE MR0175ISO 15156

The standard for materials in sour service, also known as ISO 15156. It limits the hardness of weld and HAZ, usually to 250 HV10, to prevent sulphide stress cracking.Read more: Offshore and marine, Hardness testing of welded joints

NDT extentEN 1090-2, ISO 17635

The percentage of welds examined with a given method, defined per weld type and execution class. Where sampling is used, the action on finding a defect must also be defined.Read more: Choosing the right NDT method for a welded joint

Non-conformity report

A record of a departure from specification, with description, cause, proposed disposition and its approval. Disposition can be repair, rework, rejection or acceptance by concession.Read more: The NCR: recording, resolving and learning from non-conformities

Non-destructive testing (NDT)ISO 17635

Examination methods that assess the weld without damaging it: visual (VT), penetrant (PT), magnetic particle (MT), radiographic (RT) and ultrasonic (UT), each with its own sensitivity and limitation.Read more: Choosing the right NDT method for a welded joint, NDT coordination: the right method, extent and evaluation

Notified body

An organisation notified by the authorities to carry out conformity assessment under a European directive or regulation, for example the PED or the Construction Products Regulation for EN 1090.Read more: Pressure equipment, CE marking of steel structures under EN 1090-1

P

P-numberASME IX

The ASME grouping of base materials with comparable weldability, comparable to the material groups of ISO/TR 15608 but with a different classification and different boundaries.Read more: ASME Section IX explained, ASME IX vs EN ISO 15614-1: two systems for procedure qualification

PassivationASTM A967, ISO 16048

Restoring the chromium oxide film on stainless steel after pickling or machining so corrosion resistance returns. Achieved chemically or by exposing clean material to oxygen.Read more: Heat tint on stainless welds: pickling and passivation

PorosityISO 6520-1 nr. 200

Gas cavities in the weld metal formed by gas that could not escape during solidification. Causes include moisture, grease, rust, insufficient gas shielding or a leaking gas line.Read more: Weld defects: recognition, causes and prevention

Positive material identification

Measurement of a component's chemical composition to rule out material mix-up, usually with a handheld XRF analyser. It must also be applied to weld metal, not just parent material.Read more: Petrochemical and process industry

Post weld heat treatmentEN 13445-4, ASME VIII

Heat treatment after welding, usually stress relief, to reduce residual stress, lower HAZ hardness and allow hydrogen to escape. Cycle and rates must be recorded.Read more: PWHT: post weld heat treatment explained

PreheatingEN 1011-2

Heating the workpiece before welding to slow cooling, limit martensite formation and let hydrogen diffuse out. The temperature follows from carbon equivalent, thickness and hydrogen content.Read more: Preheating in welding: when is it required

Pressure Equipment Directive2014/68/EU

Directive 2014/68/EU for pressure equipment. It classifies equipment in categories I to IV and sets, per category, the conformity assessment module and the extent of notified body involvement.Read more: Welding under the PED 2014/68/EU: categories and approvals, Pressure equipment

Procedure Qualification RecordASME IX

The ASME term for the record of a welding procedure qualification: the parameters actually used and the test results. The European equivalent is called a WPQR.Read more: The procedure qualification record (PQR): what it is and how it works

Punch list

The list of outstanding items found at an inspection or handover, with the responsible party, the disposition and the deadline per item. Category A blocks handover, category B does not.Read more: Punch list management: from open item to clean handover

pWPSISO 15609, ISO 15614

Preliminary Welding Procedure Specification: the provisional procedure used to weld the test coupon. If testing passes, it becomes a definitive WPS via the WPQR.Read more: Writing a pWPS: variables, sources and pitfalls

Q

Quality control plan

The project document describing how quality is assured, who is responsible for what and which standards apply. The ITP is usually an annex to it.Read more: The quality control plan for your fabrication project

R

Range of qualificationISO 15614-1, ISO 9606-1

The range of thicknesses, diameters, materials, positions and process variants covered by a completed qualification. Welding outside that range means the work is formally not qualified.Read more: Qualification range for thickness and diameter under EN ISO 15614-1, How to determine whether an existing WPQR covers your application

Residual stress

Stress remaining in a structure after loading is removed, caused by uneven shrinkage during welding. It adds to service stress and promotes cracking.Read more: Controlling weld distortion: causes, types and measures, PWHT: post weld heat treatment explained

S

Sensitisation

The formation of chromium carbides at grain boundaries in austenitic stainless between roughly 450 and 850 degrees, leaving them chromium depleted and corrosion prone. Prevented by L grades and low heat input.Read more: Welding austenitic stainless steel: 304 and 316

Shielding gasISO 14175

The gas that shields the weld pool and arc from the air. Inert in MIG and TIG (argon, helium), active in MAG through additions of carbon dioxide or oxygen, which stabilise the arc and influence penetration.Read more: Selecting shielding gas

Slag inclusionISO 6520-1 nr. 301

Slag trapped between runs or in the root because it was not fully removed before the next run. Most common with covered electrodes and submerged arc welding.Read more: Weld defects: recognition, causes and prevention

Stress relief annealingEN 13445-4

A heat treatment holding the structure at a temperature below the transformation point so residual stresses relax. For steel usually 550 to 620 degrees, with controlled heating and cooling rates.Read more: PWHT: post weld heat treatment explained

Submerged arc welding (121)ISO 4063

Arc welding with the arc burning beneath a flux bed, with very high deposition rate and an efficiency factor of 1.0. Suited to long, straight seams in the flat position.Read more: Submerged arc welding (121): productive and controllable

T

Tack weldEN 1090-2

A short weld holding parts temporarily in position. Tacks are welded under the same procedure as the main weld and must be consumed or removed, because they are a common source of cracking.Read more: Planning the welding sequence

Throat thicknessISO 2553, EN 1993-1-8

The height of the largest isosceles triangle that fits within the cross section of a fillet weld, measured from the theoretical root. Throat thickness is the design dimension for fillet weld strength, not the leg length z.Read more: Calculating the throat thickness of a fillet weld

Through thickness propertyEN 10164

Steel with guaranteed properties in the through thickness direction, designated Z15, Z25 or Z35. Required where a weld introduces tensile stress perpendicular to the plate surface, to prevent lamellar tearing.Read more: Full penetration: when required and how to prove it

TIG welding (141)ISO 4063

Arc welding with a non-consumable tungsten electrode under inert gas, with or without filler. Process 141 to ISO 4063, the preferred method for root runs, thin sections and stainless steel.Read more: TIG welding (141) and orbital welding of pipework

TOFDISO 10863

Time of Flight Diffraction: an ultrasonic technique determining flaw height from the time difference between waves diffracted at the upper and lower tips. Highly accurate in height, with dead zones at the surfaces.Read more: Phased array and TOFD

TraceabilityEN 1090-2

The demonstrable ability to trace every material used and every weld back to its certificate, welder and procedure. A hard requirement in higher execution classes and for pressure equipment.Read more: Material certificates 3.1 and 3.2 to EN 10204, Weld map and weld log: traceability for every weld

Tungsten inclusionISO 6520-1 nr. 3041

A particle of tungsten entering the weld pool in TIG welding because the electrode touched the pool or the filler. It appears as a bright spot on a radiograph.Read more: TIG welding (141) and orbital welding of pipework

U

UndercutISO 6520-1 nr. 5011

A groove along the weld toe where parent material has melted away without being filled by weld metal. It acts as a notch and initiates fatigue cracks under fluctuating load.Read more: Weld defects: recognition, causes and prevention, Fatigue of welded joints

V

Vendor inspection

Inspection at a supplier on behalf of the client, to establish that production follows the purchase specification. It covers document review beforehand, attendance at hold points and final inspection.Read more: Vendor inspection and expediting at your suppliers, Vendor inspection abroad: control of quality at a distance

Visual testing (VT)ISO 17637

The first and mandatory examination method for every weld: assessment by eye, with aids and gauges, under adequate lighting. It finds surface defects and shape deviations but nothing beneath the surface.Read more: Visual testing of welds to ISO 17637, Visual weld inspection: from preparation to report

W

Weld log

A record capturing, per weld, who made it, under which procedure, when, with which material and what examination was performed. Indispensable for traceability and release.Read more: Weld map and weld log: traceability for every weld

Weld map

A drawing on which every weld is given a unique number, linked to the applicable procedure and the required examination. The basis for the weld log and for traceability.Read more: Weld map and weld log: traceability for every weld

Weld rootISO 6520-1

The side of the weld lying deepest in the joint, opposite the cap. The root is often the most structurally critical and simultaneously the hardest to assess without examination.Read more: Full penetration: when required and how to prove it

Weld run

A single pass of the arc depositing weld metal. A multi-run weld consists of a root run, fill runs and a capping run, each with its own parameters and heat input.Read more: Calculating and controlling heat input

Weld toe blending

The transition from weld metal to parent material at the surface. A smooth transition with a generous radius reduces notch effect; a sharp transition is where the crack starts under fluctuating load.Read more: Fatigue of welded joints

Welding operatorISO 14732

The person who sets up and monitors a mechanised or automatic welding process without guiding the arc by hand. Qualified to ISO 14732 rather than ISO 9606.Read more: Operator qualification to ISO 14732 for mechanised and orbital welding, Robot welding: qualification and control

Welding positionISO 6947

The orientation in which welding takes place, designated to ISO 6947: PA flat, PB horizontal fillet, PC horizontal, PE overhead, PF vertical up and PG vertical down. Position is an essential variable.Read more: Welder qualification to ISO 9606-1

Welding procedure qualificationISO 15614, ASME IX

The process in which a test coupon and testing demonstrate that a welding procedure produces a joint with the required properties. The result is a WPQR or PQR.Read more: When do you need a WPQR?, WPQR qualification to EN ISO 15614-1 and ASME IX

Welding symbolISO 2553

The standardised representation on a drawing indicating weld type, size, length, position and any supplementary requirements. Its position relative to the reference line determines which side is welded.Read more: Reading welding symbols to ISO 2553

Witness point

A point in the process where a party is invited to attend, but where work may proceed if they do not appear. In contrast to a hold point.Read more: How to write an ITP that works in practice

Workpiece temperatureISO 13916

The temperature of the material at the location and moment of welding, measured with a contact thermometer or temperature indicating crayon. Measured at a prescribed distance from the joint, not on the weld itself.Read more: Preheating in welding: when is it required

WPQRISO 15614-1

Welding Procedure Qualification Record: the report stating what was actually welded during qualification and which test results were achieved. It underpins one or more WPSs.Read more: WPS versus WPQR: what is the difference?, How to determine whether an existing WPQR covers your application

WPSISO 15609-1

Welding Procedure Specification: the working document for the welder containing every defined variable, from material and consumable to current, voltage, position, preheat and interpass temperature.Read more: WPS development and management, WPS versus WPQR: what is the difference?

X

XRF analysis

X-ray fluorescence: a measurement determining elemental composition from the characteristic radiation a material emits. The basis of handheld PMI, with limited sensitivity to light elements.Read more: Petrochemical and process industry