3 - Some Terminologies in Welding

SOME TERMINOLOGIESIN WELDING

TYPES OF WELDING JOINTButt JointTee JointCorner JointLapped JointEdge Joint

EdgeOpen & Closed CornerLapTeeCruciformButtJoint Terminology

JOINT DESIGNConsists of:- types of joint- joint preparation (such as square, bevel, V, J or U groove)- joint geometry (such as groove/bevel angle, root opening, root face)

Included angleRoot GapRoot FaceAngle of bevelRoot FaceRoot GapIncluded angleRoot RadiusSingle -V ButtSingle - U ButtTypes of Joint Preparations

Root GapRoot FaceRoot FaceRoot GapRoot RadiusSingle Bevel ButtSingle J ButtAngle of bevelAngle of bevelLandTypes of Joint Preparations

BevelVeeJUSingle sided joint preparations are normally made on thinner materials, or when access from both sides is restrictedSingle Joint Preparations

Double sided joint preparations are normally made on thicker materials, or when access from both sides is unrestrictedDouble Joint Preparations

TYPES OF WELDFillet WeldSingle Square / Double Square Groove WeldSingle Bevel / Double Bevel Groove WeldSingle V / Double V Groove WeldSingle J / Double J Groove WeldSingle U / Double U Groove Weld

A_________Welded butt jointButtA_________Welded butt jointFilletA____________Welded butt jointCompoundWelded Butt JointsSingle V Groove WeldDouble Fillet WeldCombination of Single Bevel Groove & Double Fillet Weld

A_________Welded T jointFilletA_________Welded T jointButtA____________Welded T jointCompoundWelded Tee JointsSingle Fillet WeldSingle Bevel Groove WeldCombination of Single Bevel Groove & Double Fillet Weld

A_________Welded lap jointFilletA_________Welded lap jointSpotA____________Welded lap jointCompoundWelded Lap JointsDouble Fillet WeldSpot WeldCombination of Spot and Double Fillet Weld

A_________Welded closed corner jointFilletA_________Welded closed corner jointButtA____________Welded closed corner jointCompoundWelded Closed Corner JointsSingle Fillet WeldSingle Bevel Groove WeldCombination of Single Bevel Groove & Fillet Weld

A_______________Welded open corner jointOutside filletA_______________Welded open corner jointInside filletA_______________Welded open corner jointDouble filletWelded Open Corner WeldsSingle Fillet WeldSingle Fillet WeldDouble Fillet Weld

WELDING POSITIONS1 Flat2 Horizontal3 Vertical4 Overhead

Welding Positions

Weld: Vertical DownwardsPipe: FixedAxis: Horizontal PG / 5G 45oWelding Positions

POSITIONS FOR FILLET WELDING 1F2F3F4F

POSITIONS FOR GROOVE WELDING (PLATE)1G2G3G4G

POSITIONS FOR GROOVE WELDING (PIPE)1G2G5G6G6GR

WELDABILITY OF MATERIALSWELDABILITY IN GENERAL the ability of material to be welded.GOOD/HIGH WELDABILITY the ease of material to be welded using cheaper mean of welding process and simple technique FABRICATION WELDABILITY the ability of the material to have good relationship with the welding process to produce sound weld and good weld geometry, free from porosity and cracks.SERVICE WELDABILITY the ability to produce weld that can sustain thermal and mechanical stresses, corrosion, and other service requirement

EXAMPLE OF WELDABILITY OF MATERIALSHIGH/GOOD WELDABILITY e.g. mild steel / low carbon steel.LOW/BAD/POOR WELDABILITY e.g. medium carbon steel, high carbon steel, high alloy steel, Stainless Steel, Aluminium

CARBON EQUIVALENTCARBON EQUIVALENT (CE) numerical value of Weldability Assessment in terms of carbon equivalent content for the measurement of the weldability of carbon steels & alloyed steels.CE = %C + %Mn/4 + %Ni/20 + %Cr/10 + %Mo/5 + %Cu/40 + %V/10 (AWS)CE < 0.5 steels are weldableCE > 0.5 crack sensitive CE < 0.4 relatively less sensitive to cracksHigh CE require preheating, use low hydrogen welding procedure

STUDENT HOME ASSIGNMENTWith the help of sketches differenciate between Weld Joint, Joint Design, type of Weld and Weld Positions.What is the European equivalent for 6G?Using sketches to describe 6G & 6F.What are the purposes of calculating the Carbon Equivalent in welding of Carbon Steels?