WPS and PQR Qualification Flashcards

A Procedure Qualification Record (PQR) was created for a groove weld on 1-inch thick carbon steel plate using the Shielded Metal Arc Welding (SMAW) process. All destructive tests were acceptable. What is the primary purpose of this PQR?

Answer: To serve as the documented record of the welding variables used to produce an acceptable test weldment.

The PQR is a record of what actually happened during the welding of a test coupon. It documents the specific variables used and the results of the tests performed. This record then serves as the evidence to support one or more Welding Procedure Specifications (WPS).

A fabricator has a qualified WPS for welding P-No. 1 to P-No. 1 base materials. A new project requires welding a P-No. 1 material to a P-No. 4 material. According to ASME Section IX, what action is required?

Answer: A new PQR must be completed to qualify a new or revised WPS.

A change in the P-Number of the base metal is considered an essential variable in most welding codes, including ASME Section IX. An essential variable change requires requalification of the procedure. This means a new test coupon must be welded using the new variables (P-No. 1 to P-No. 4), tested, and documented on a new PQR to support a new or revised WPS.

When developing a Welding Procedure Specification (WPS) supported by a PQR, which of the following is true?

Answer: Several WPSs with different non-essential variables can be written from a single PQR.

A single PQR documents the successful welding of a test coupon with specific essential variables. From this one successful test (PQR), multiple WPSs can be written. These WPSs can vary in their non-essential variables (e.g., groove design, technique) while still being supported by the same PQR, as changes in non-essential variables do not require requalification.

A welder is performing production welding using a qualified WPS. The WPS specifies a maximum interpass temperature of 450°F. The inspector measures the temperature between passes and finds it to be 500°F. What is the correct course of action?

Answer: Stop the work until the base material cools to below the specified maximum interpass temperature.

The WPS provides the legally required instructions for production welding. Adherence to all parameters, including maximum interpass temperature, is mandatory. A deviation from this essential variable requires work to be stopped until the condition is corrected to comply with the WPS.

Which of the following changes would be considered a supplementary essential variable under ASME Section IX, requiring WPS requalification ONLY when notch-toughness tests are required?

Answer: A significant increase in heat input.

Supplementary essential variables are conditions that affect the notch-toughness properties of the weldment. A significant increase in heat input can negatively impact toughness. Therefore, if the application requires notch-toughness testing (e.g., for low-temperature service), an increase in heat input beyond what was recorded on the PQR would require requalification of the WPS.

A PQR was qualified using the Gas Metal Arc Welding (GMAW) process with a shielding gas of 75% Argon / 25% CO2. The resulting WPS is to be used for a production weld. Which of the following shielding gases would require a new PQR?

Answer: 100% CO2.

According to most codes, such as AWS D1.1, a change in the shielding gas from a mixture to a single gas (or vice-versa), or a significant change in the percentage composition, is an essential variable. Changing from an Argon/CO2 mixture to 100% CO2 is a fundamental change that affects arc characteristics and weld metal properties, thus requiring requalification. Minor variations in the mixture percentages may be allowed within a certain range without requalification.