A spot welded Lap joint* A fillet welded Lap joint* Text Page Ref 1:9/10 Example Slide of User Functions Relevant course text section:page/pages if applicable Time guide the slide should be finished by Indicates a click is required to progress to the next element
Example Slide of User Functions. Time guide the slide should be finished by. Lap Joints. A fillet welded Lap joint *. A spot welded Lap joint *. Indicates a click is required to progress to the next element. Relevant course text section : page/pages if applicable. Text Page Ref 1:9/10. - PowerPoint PPT Presentation
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A spot welded Lap joint*
A fillet welded Lap joint*
Text Page Ref 1:9/10
Example Slide of User Functions
Relevant course text section:page/pages if applicable
Time guide the slide should be finished by
Indicates a click is required to progress to the next element
A Joint:* A configuration of members
A Weld:* A union between materials caused by heat, and or pressure
Text Page Ref 1:1
Butt welds:*
Fillet welds:*
Spot/Seam welds:*
Plug/Slot welds:*
Edge welds:*
Closed corner
Open corner*
T joints: *
Lap joints: *
Corner joints:*
Butt joints: *
This has major effects on economics and distortion control etc
The root face, root gap and angle of bevel values, the choice of single, or double sided preparations, are dictated only by the type of welding process, the position and accessibility of the joint*
The basic rule is this:The basic rule is this:
The more you take out, then the more you must put back in*
Remember, the purposes of a weld preparation is to allow access for the welding process, penetration and fusion through the area of the joint and its faces*
Angle of bevel*
Included angle*
Root gap*
Root face*
Root radius*
Root landing*
Single V
Single bevel
Single J
Single U*
Double bevel
Double V
Double J
Double U*
A butt welded butt joint*
A fillet welded butt joint*
A compound welded butt joint*
A butt welded T joint*
A fillet welded T joint*
A compound welded T joint*
A compound welded Lap joint*
A spot welded Lap joint*
A fillet welded Lap joint*
A butt welded Closed Corner joint*
A fillet welded Closed Corner joint*
A compound welded Closed Corner joint*
An outside fillet welded Open Corner joint*
An An inside filletinside fillet welded Open C welded Open Corner jointrner joint**
A double fillet welded Open Corner joint*
1 2
43
A
B
A + B = Excess Weld Metal**
Weld Face*
Weld Width*
Design Throat Thickness*1.2.3.4. Weld Toes*
Fusion Boundary*
Fusion Zone*Weld Root*HAZ*
Actual Throat Thickness*
Weld face*
Vertical Leg Length*
Horizontal Leg Length*
Design throat*Actual throat*
Excess weld metal **
“s” = Effective throat thickness
sa
“a” = Nominal throat thickness
Deep throat fillet welds from FCAW & SAW etc*
*
80°
20°
6 mm
3 mm*
Very Poor Weld Toe Blend Angle
Improved Weld Toe Blend Angle
Extremely poor toe blend, but excess weld metal is within limits*
It is also possible that the height of excess weld metal is within within the acceptedthe accepted limitlimit of an applied standard, but the toe blend is unacceptableunacceptable, as shown below*
Types of Preparation: Bevel’s. V’s. J’s. U’s. Single & Double Sided.
Types of Joint: Butt. T. Lap. Corner (Open & Closed)
Types of Weld: Butt. Fillet. Spot. Seam Plug. Slot. Edge.
Weld Preparation: Preparing a joint to allow access and fusion.
Joint: A Configuration of members
Weld: A Union of materials
Describe your duties to your code of practise. “CSWIP Exam”*
It is the duty of all welding inspectors: To ensure that welding operations are carried out in accordance with written, or agreed practices or specifications
3)3) Rockwell hardness test:Rockwell hardness test: Uses a ball, or diamond depending on the scale*
10 x 10 mmMachined notch
Pendulum Hammer
Location of specimen
The specimen may be tested from different areas of the weld.*
Graduated scale of absorbed energy in Joules*
1)1) Charpy V test:Charpy V test: 10 x 10 (Specimen horizontal) Joules*
2)2) Izod test:Izod test: 10 x 10 (Specimen vertical) Ft.lbs*
3)3) CTOD test:CTOD test: Specimen used is actual design size. Detailed fracture report. mm*
Testing temperature
Joules absorbedJoules absorbed
Ductile Fracture47 Joules
28 Joules
Transition Zone
Transition Temperature Range
Mn < 1.6 % increases toughness in steels*
Brittle Fracture
Three specimens are normally tested at each temperature.
-40 -30 -20 -10 0 +10 +20 +30 + 40
Transverse reduced test piece*
A Section of weld is cut, or machined out acrossacross the test piece and tested in tension to failure. The units are usually in N/mm²
Weld
HAZ
Plate material
Test gripping area
Radius (For radius reduced test specimens only)
Reduced Section
Used to assess the tensile strength of the weld metal
Direction of test
Tensile test piece cut along weld specimen.
Direction of the test *
BS 709 / BS En 10002BS 709 / BS En 10002 All Weld Metal Tensile
Testing
Firstly, before the tensile test 2 marks are made 50mm apart
During the test, Yield point & Tensile strength are measured
The specimen is put together and the marks are re-measured
A new measurement of 75mm will indicate Elongation E50 %*
50 mm
75 mm
3) Lack of Root Fusion
1) Excess Weld Metal Height 8) Poor Toe Blend*
4) Slag inclusion & Lack of inter-run fusion
2) Lack of Sidewall Fusion5) Root Penetration
6)Porosity
7) Laminations
Bend tests are used to establish fusion in the area under test
FormerTest Piece
Lack of root fusion shown here*
Further tests include face, side and longitudinal bend tests*
For material over 12 mm thickness, side bend test may be used*
Force
A Guided root bend test*Guide
Specimen prior to test* Specimen after test*
Saw cut
Hammer blow
Full fracture
Any strait line indicates a “Lack of root fusion”*
1
3
1
Fracture lineFracture line
1
2
3
Inspect both surfacesInspect both surfaces
2
2 3
Line of fusion
X
Y
X
A
B
Inclusions on fracture line*
C
Lack of root penetration or fusion
Hammer blowSaw Cuts
Fracture line
Inspect both surfaces
We test welds to establish minimum levels of mechanical properties, and soundness of the welded joint
We divide tests into Qualitative & Quantitative methods:*
Qualitative: (Have no units)
Macro tests
Bend tests
Fillet weld fracture tests
Butt Nick break tests*
Qualitative: (Have no units)
Macro tests
Bend tests
Fillet weld fracture tests
Butt Nick break tests*
Quantitative: (Have units)
Hardness (VPN & BHN)
Toughness (Joules & ft.lbs)
Strength (N/mm2 & PSI)
Ductility/Elongation (E%)
Quantitative: (Have units)
Hardness (VPN & BHN)
Toughness (Joules & ft.lbs)
Strength (N/mm2 & PSI)
Ductility/Elongation (E%)
The main difference between Macro & Micro is that Micro is the study of the micro-structure at much higher magnification
The limit of Macro inspection is magnification < X 10
The specimen is usually cut from a stop/start in the test piece
The cut specimen is polished to a fine finish (400 grit)
The specimen must be inspected, before etching*
Remember! The process of inspection is to first:
Observe, then Report, then Compare!*
Use the TWI macro sheets provided to observe and then make a report on a separate sheet of what you observe*
When you have finished reporting, turn the macro sheet over and compare your observations with those given on the back of the sheet* (1 hour)
A definition of the term “Procedure”?*A systematic method of producing an aim*
Therefore, a “Welding procedure” is?*
A systematic method of producing a sound weld*
• Most procedures are approved, but not all? An approved welding procedure is one that has been tested to ensure that the procedure as carried out, produces a weld that
satisfies a minimum level of quality for the mechanical, physical or chemical properties desired. If these are not required, then “procedural approval is unnecessary”*
• Do all welding procedures need to be approved?*
• Most production welding procedure are formatted on written documents or computer spreadsheets, but they need not be written and may be a product of experience
• Do all welding procedures need to be written?*
What do “you” think about the following statements?*
A Welding Procedure is a recipe of variable parameters, which will produce the same results of certain quality & properties if carried out in the same way each time*
To evaluate a Provisional Welding Procedure we need to check if all the parameters set will work together to produce the desired results*
.*
Once the weld has been completed it is usually visually inspected, then Radiography or Ultrasonic testing is usually applied*
If all the desired properties have been met, then a procedure qualification record (WPQR or WPAR) is completed with all the test results, and the procedure then becomes qualified*
Finally, and most importantly, Mechanically tested to ensure that the desired level of mechanical properties have been met*
A CSWIP 3.2 Senior Welding Inspector is normally responsible for the testing and approval of welding procedures*
From this data, a workable document for production welding is prepared and called a Welding Procedure Specification. (WPS)*
a) Diameter of pipe, or thickness of plate
b) Welding position, amperage range, or number of runs
c) Process (On multi process procedures only)
d) Certain material groups
e) Change of consumable to one of the same classification Only if the class is given in the original procedure
f) Heat input range (kJ/mm)*
Examples of “Extents of Approval” include:*
Once the procedure has been approved it is then important to test each welder, to ensure that he has the skill to reach the minimum level of quality in the weld, as laid down in the application standard*
There is no need to carry out the mechanical tests of the procedure, although bend tests are often used to ensure good side wall fusion
Normally; visual, x ray, bends, fractures and macro’s are used in welder approval tests*
1) Check the welding process, condition of equipment and test area for suitability.2) Check that extraction systems, goggles and all safety equipment are available.3) Check grinders, chipping hammers, wire brush and all hand tools are available.4) Check materials to be welded are correct and stamped correctly for the test.5) Check welding consumables specification, diameter, and treatment with WPS.6) Check the welder’s name and stamp details are correct.7) Check that the joint has been correctly prepared and tacked, or jigged.8) Check that the joint and seam is in the correct position for the test.9) Explain the nature of the test and check that the welder understands the WPS.10) Check that the welder carries out the root run, fill and cap as per the WPS.11) Ensure welders identity and stop start location are clearly marked.12) Supervise or carry out the required tests and submit results to Q/C department.*
When supervising a welder test the welding inspector should:*
A CSWIP 3.1 Welding Inspector is normally responsible for the