Joint design and test coupon thickness.

Base metal P-number and deposited metal thickness.

Type of welding process and test coupon thickness.

Electrode-flux class and electrical characteristics.

Minimize the number of performance qualifications.

Minimize the number of welding procedure qualifications.

Define the welding characteristics.

Designate similar chemical compositions.

Welding technique

Groove design

Base metal

Welding position

Under low humidity conditions.

In warm holding ovens.

In sealed plastic containers.

In tightly sealed ovens.

300°F (150°C)

500°F (260°C)

900°F (480°C)

1000°F (540°C)

Electrode diameter and strength

Electrodes and welding rods

Chemical composition of the deposited weld metal

Base metal and group number

Chemical composition of the deposited weld metal.

Comparable base metal ultimate strength values.

Weldability characteristics of the metal.

Type and strength of base metal.

200

215

225

241

To provide direction to the welder making production welds.

To establish the properties of the weldment.

To document that a welder has correctly followed a WPS.

To establish a welder's capability to make a quality weld.

Reduce travel speed

Proper shielding

Lower heat input

Arc length control

More susceptible to distortion during welding.

Less susceptible to cracking during welding.

More susceptible to brittle fracture.

Less susceptible to brittle fracture.

E7048-H4

E7048

E7018-A1

E7018

Deposition rates are lower than GMAW.

The process cannot be used in areas of limited access.

It has low tolerance for contaminants.

The process is sensitive to wind and draft.

ONCE

TWICE

THREE TIMES

FOUR TIMES

A feathery line of longitudinal orientation located at the center of the weld image.

Elongated lines of darker density, irregular in width, and slightly winding in the lengthwise direction.

A feathery, twisted line of darker density running across the width of the weld.

An irregular darker line near the center of the width of the weld image along the edge of the root pass image.

Welder qualification

Maintaining project schedule

Welding program effectiveness

Fabrication quality control

Arc drift.

Arc strike.

Arc blow.

Arc deflection.

Welding rates are significantly lower than those obtained with SMAW.

Process is primarily suitable for only carbon steel and low alloy steels.

Process is limited to a flat position.

Weld is not visible during the welding process.

Coating characteristics.

Chemical composition.

Strength of the filler metal.

Welding position.

Whether postweld heat treatment (PWHT) will be needed.

Whether preheat will be needed.

The theoretical carbon content of a steel.

The weldability of a steel, based on carbon content.

MT

UT

ET

RT

Electrodes should never be stored in an oven that is used for food storage.

Low-hydrogen electrodes may be stored in ovens with cellulose-based electrodes, but must be in their original, unopened containers.

Electrode ovens should be heated by any means, but must have automatic heat controls and visible temperature indicators.

Low-hydrogen electrodes should never be stored with stainless-steel electrodes.

PQRs qualified on P8 materials also qualify for P1 materials.

Welding procedures must be supported by more than one PQR.

All PQRs must be qualified with impact testing.

One PQR may support several WPSs.

Yield.

Strain.

Stress.

Plasticity.

WPQ to verify that the welder is qualified to perform the welding, given its position and process.

WPQ to verify that the specification in use is correct.

PQR to verify that the welder is qualified to perform the welding, given its position and process.

WPS to verify that the welder is qualified to perform the welding, given its position and process.

It is more sensitive to drafts and wind than GMAW.

It has lower deposition rates than SMAW.

Shielding must always be provided by an externally supplied gas.

Large volumes of welding fumes are generated.

Explosion or unstable reaction with the addition of localized heat.

Exothermic decomposition or explosion.

Carbon steel will burn in the presence of chlorine and high heat.

Hydrogen released during welding process can initiate hydrogen-assisted cracking.

A definition of welds that should be inspected in refinery and chemical plant equipment.

A definition of specific techniques and practices that should be used for welding inspection.

Guidance on the extent and scope of inspection required for specific types of welds.

Guidance on welding inspection during the fabrication and repairing of refinery equipment and piping.

Chemical composition.

Electrode operating characteristics.

Welding position.

Coating operating characteristics.

They should be corrected before welding proceeds further.

The inspector should seek engineering input on whether the defect is actually acceptable.

The inspector should determine whether the weld may be acceptable for the intended service.

The inspector should examine all welds produced by the same welder.