API 653 Code Requirements 4

Question 1

Per API 653, when is a hydrostatic test required after repairs to a tank?

Accepted Answer

After repairs to the shell or bottom that affect structural integrity as defined in the standard

Answer

API 653 requires hydrostatic testing after certain shell and bottom repairs that could affect the tank's structural integrity, as specified in the standard.

Question 2

What does the term 'alteration' mean under API 653, as distinct from a 'repair'?

Accepted Answer

A physical change to a tank component that affects its design, capacity, or operating conditions

Answer

An alteration under API 653 is a physical change that affects the tank's design configuration, capacity, or operating conditions, distinguishing it from like-for-like repair.

Question 3

According to API 653, what is the minimum preheat temperature required for welding on tank shell plates with carbon equivalent (CE) above 0.43?

Accepted Answer

As required by applicable welding procedures per AWS or ASME standards

Answer

API 653 requires preheat to be as specified in the applicable welding procedure standard, such as AWS D1.1 or ASME Section IX, based on material CE.

Question 4

Under API 653, what is the minimum overlap required when installing a new bottom lap-welded to an existing bottom?

Accepted Answer

1.5 inches

Answer

API 653 specifies a minimum 1.5-inch overlap for new bottom plates installed over existing bottom plates using lap-welded construction.

Question 5

Per API 653, what action must be taken when the remaining corrosion allowance on the tank shell is insufficient to last until the next scheduled internal inspection?

Accepted Answer

Repair, rerate, or take the tank out of service

Answer

When corrosion allowance is insufficient for the next inspection interval, API 653 requires the tank to be repaired, rerated to a lower operating level, or removed from service.

(API 653) API 653 Aboveground Storage Tank Inspector Certification Practice Test

(API 653) API 653 Aboveground Storage Tank Inspector Certification Practice Test

API 653 Code Requirements 4