API 510 Welding Inspection 5

Question 1

Under API 510, a 'hot tap' welding procedure on an in-service pressure vessel requires special consideration primarily because:

Accepted Answer

Welding is performed on equipment containing fluid under pressure and temperature, requiring special heat input controls to prevent burn-through

Answer

Hot taps never require welder qualification

Answer

Hot taps are exempt from all code requirements

Answer

Only visual inspection is needed for hot tap welds

Question 2

When reviewing radiographs of a pressure vessel longitudinal seam weld, the inspector identifies elongated dark linear indications aligned with the weld axis. This most likely represents:

Accepted Answer

Slag inclusions or incomplete fusion

Answer

Scattered porosity

Answer

Tungsten inclusions

Answer

Base metal laminations

Question 3

Per API 510 and ASME Section IX, a welder's performance qualification (WPQ) expires if the welder has not welded using the qualified process for a period exceeding:

Accepted Answer

6 months

Answer

3 months

Answer

12 months

Answer

24 months

Question 4

An inspector notices that a weld repair on a pressure vessel shell was made with heat input significantly higher than qualified in the WPS. The primary concern with excessive heat input in carbon steel is:

Accepted Answer

Grain growth in the HAZ leading to reduced toughness and potential cracking susceptibility

Answer

Increased risk of underfill

Answer

Faster weld completion and reduced cost

Answer

Improved corrosion resistance of the weld metal

Question 5

Per API 510, who is responsible for verifying that welders performing repair work on a pressure vessel are currently qualified for the applicable WPS?

Accepted Answer

The repair organization and the Authorized Pressure Vessel Inspector

Answer

The welding foreman only

Answer

The plant owner only

Answer

The jurisdiction authority only

Question 6

When examining a weld repair on a pressure vessel for hydrogen-induced cracking (HIC), the inspector should schedule NDE examinations:

Accepted Answer

At least 24-48 hours after welding is complete and the weld has cooled to ambient temperature

Answer

Immediately upon weld completion while the metal is still warm

Answer

Only if the weld appears visually suspicious

Answer

Before post weld heat treatment is performed

Question 7

A pressure vessel repair weld on a P-No. 4 (Cr-Mo alloy steel) material requires PWHT. If the PWHT cannot be performed due to equipment constraints, which API 510 alternative technique might be considered for a localized repair?

Accepted Answer

Apply temper bead welding technique per approved engineering procedures

Answer

Skip PWHT entirely and rely on visual inspection

Answer

Use a lower-strength filler metal to avoid the PWHT requirement

Answer

Perform a hydrostatic test instead of PWHT