Welding procedure specification

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CSWIP Welder Training
Weld Procedures

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Welding Procedures
Welding Procedures
(BS EN 288)
(BS EN 288)

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Welding Procedures
Welding Procedures
Producing a welding procedure involves:

Planning the tasks

Collecting the data

Writing a procedure for use of for trial

Making a test welds

Evaluating the results

Approving the procedure

Preparing the documentation

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In most codes reference is made to how the procedure are to be
devised and whether approval of these procedures is required.
The approach used for procedure approval depends on the code:
Example codes:

AWS D.1.1: Structural Steel Welding Code

BS 2633: Class 1 welding of Steel Pipe Work

API 1104: Welding of Pipelines


BS 4515: Welding of Pipelines over 7 Bar
Other codes may not specifically deal with the requirement of a
procedure but may contain information that may be used in writing
a weld procedure

EN 1011Process of Arc Welding Steels
Welding Procedures
Welding Procedures

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Welding Procedures
Welding Procedures
Parent material
•
Type (Grouping)
•
Thickness
•
Diameter (Pipes)
•
Surface condition)

Welding process
•
Type of process (MMA, MAG, TIG, SAW etc)
•
Equipment parameters
•
Amps, Volts, Travel speed

Welding process
•
Type of process (MMA, MAG, TIG, SAW etc)
•
Equipment parameters
•
Amps, Volts, Travel speed

Welding Consumables

•
Type of consumable/diameter of consumable
•
Brand/classification
•
Heat treatments/ storage
Components of a welding procedure
Components of a welding procedure

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Welding Procedures
Welding Procedures

Joint design
•
Edge preparation
•
Root gap, root face
•
Jigging and tacking
•
Type of baking

Welding Position
•
Location, shop or site
•
Welding position e.g. 1G, 2G, 3G etc
•
Any weather precaution

Welding Variables
•
Run sequences
•
Back gouging
•
Interpass temperatures

Thermal heat treatments

•
Preheat, temps
•
Post weld heat treatments e.g. stress relieving

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Welding Procedures
Welding Procedures

When the data has been collected, the procedure must

be validated by producing a test weld, weld procedure
test (WPT).

A number of standards provides information with
regards to approving a procedure, but normally this will
require the WPT to be tested by NDT and mechanical
testing.

The locations and tests required will be given in the
applicable code or standard

Most codes and standards provide a report format to
record the results
Approving the procedure:
Approving the procedure:

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Welding Procedures
Welding Procedures
Examination and testing requirements of a WPT for
procedure approval (BS EN 288)

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Welding Procedures
Welding Procedures
After the testing is completed and all the relevant results
collated, the results need to be assessed in accordance with
the relevant code/standard. The results are then generally
recorded.


pWPS:
pWPS: Preliminary Welding Procedure Specification
Before procedure approval.


WPS
WPS
:
: Welding Procedure Specification
After procedure approval


WPAR (WPQR):
WPAR (WPQR): Welding Procedure Approval Record
Welding procedure test record

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Welding Procedures
Welding Procedures
Once the welding procedure has been approved, If any
essential variable is changed during production the WPS may
require re-approval. Most codes/procedures dealing with
procedure qualifications provide a list of what is an essential
or non-essential variable.
Object of a welding procedure test
Object of a welding procedure test

To give maximum confidence that the welds mechanical and
metallurgical properties meet the requirements of the

applicable code/specification.

Each welding procedure will show a range to which the
procedure is approved (extent of approval)

If a customer queries the approval evidence can be supplied
to prove its validity

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Example:

Example:
Welding Procedure
Welding Procedure
Specification (WPS)
Specification (WPS)

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Welder Approvals
Welder Approvals
(BS EN 287)

(BS EN 287)

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Welder Approval
Welder Approval
Numerous codes and standards deal with welder
qualification, e.g. BS EN 287.
Once the content of the procedure is approved the next
stage is to approve the welders to the approved procedure. A
welders test know as a Welders Qualification Test (WQT).

Object of a welding qualification test
Object of a welding qualification test
.

To give maximum confidence that the welder meets the
requirements of the approved procedure (WPS).

The test weld should be carried out on the same material
and same conditions as for the site welds

The welder who carries out the procedure qualification weld
automatically qualify when the procedure qualifies

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Welder Approval
Welder Approval
Information that should be included on a welders test
certificate are:
1. Welders name and identification number
2. Date of test and expiry date of certificate
3. Standard/code e.g. BS EN 287
4. Test piece details
5. Welding process, welding parameters, amps, volts
6. Welding parameters, amps, volts
7. Consumables, flux type and filler classification details
8. Sketch of run sequence, welding positions
9. Joint configuration details
10.Material type qualified, pipe diameter etc
11. Test results, remarks
12.Test location and witnessed by
13.Extent (range) of approval

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Range of approval according to electrode flux type
Range of approval
according material
groups
BS EN 287

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Welder Approval
Welder Approval
The inspection of a welders qualification test.

It is normal for a qualified inspectors usually from an
independent body to witness the welding.

Under normal circumstances only one test weld per welder
is permitted

If the welder fails the test weld and the failure is not the fault
of the welder e.g. faulty welding equipment then a re-test
would be permitted.

The testing of the test weld is done in accordance with the
applicable code, but it is not normal to carry out test that test
for the mechanical properties of welds e.g. tensile, charpy
and hardness tests.

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Welder Approval
Welder Approval
Tests methods required for welder qualification
(BS EN 287)

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Example:
Example:
Welder Approval
Welder Approval
Qualification
Qualification
Certification
Certification

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Any Questions?Any Questions?

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QU 1. State six essential variables in a welding procedure.
Questions
Questions
QU 2. What do you understand by the term extent of approval and
give four examples.
QU 3. Describe what you understand by a welding procedure
specification, A welding procedure approval record and a welder
certificate
QU 4. What is the reason for approving a welding procedure and
a welder
QU 5. Give three reasons why a welder may require re-
qualification.