Pressure Vessel
A pressure vessel is a closed container designed to hold gases or liquids at a pressure substantially different from ambient, typically constructed per ASME Section VIII and inspected in service per API 510.
Definition
Pressure vessels include reactors, separators, columns, drums, accumulators, and similar equipment. NDT scope includes weld inspection during construction (per Section VIII), and in-service external (every 5 yr), internal (every 10 yr), and thickness inspection (every 10 yr) per API 510.
What it is
A closed container designed to hold pressure significantly different from ambient — the asset class around which most inspection codes grew, because stored pressure energy makes failure consequences severe.
Damage mechanisms in service
Lifecycle: designed and built to a construction code (ASME VIII most commonly), then handed to an in-service regime (API 510 or jurisdictional rules) that runs on measured condition — CML thickness histories, corrosion rates, remaining life, and damage-mechanism-driven examination beyond simple thinning: cracking services get surface methods, hydrogen services get specialised UT.
Governing codes
ASME Section VIII (design/construction), API 510 (in-service), API 572 (inspection practices), API 571 (damage mechanisms), NBIC in many jurisdictions.
The common oversight
Inspecting every vessel as a general-thinning problem. The vessel's service assigns its mechanisms — amine cracking, HTHA, CUI at supports — and each mechanism has locations and methods a routine grid survey does not cover.
Where Pressure Vessel fits in an inspection programme
A term is only useful when it connects to a decision. Pressure Vessel appears in written procedures, in technique sheets, and in the records an owner or accreditation body reviews afterwards — which means the way it is defined in your documentation has to match the way it is applied on site. Where the two drift apart, audits find it. Atlantis writes and reviews procedures against the governing codes, trains inspection personnel to apply them, and builds the record-keeping that makes the evidence retrievable years later. Procedure development and code consulting · NDT training and certification · Ask us about your programme.
Related terms
- Storage Tank — A storage tank is a low-pressure, large-volume welded container for the storage of liquids — typically atmospheric (API 650), low pressure (API 620), or for water (AWWA D100) — inspected in service per API 653.
- Heat Exchanger — A heat exchanger is a pressure vessel that transfers heat between two fluid streams, with the shell-and-tube configuration the most common in refineries, chemical plants, and power generation, inspected primarily by tube ET/IRIS and shell-side UT.
- API 510 Pressure Vessel Inspection Code — API 510 is the inspection, repair, alteration, and rerating code for in-service pressure vessels in refineries and chemical plants, requiring periodic external and internal inspection by certified API 510 inspectors.
- ASME Section VIII — ASME Section VIII is the ASME BPVC chapter covering rules for construction of pressure vessels, with Division 1 (design by rule), Division 2 (design by analysis), and Division 3 (high-pressure vessels), each invoking ASME Section V NDT requirements.
Further reading
pressure vessel inspection and compliance
More asset-type terms
Fired Heater · Pipeline · FPSO · Riser · Jacket · Topsides · Wellhead · Christmas Tree · Blow-Out Preventer · Valve
Where this comes up in practice
Terms like this one appear in three places that matter commercially: the written practice that governs how your personnel are qualified, the procedures and technique sheets that define how an examination is actually performed, and the evidence an auditor or client asks for when they want to know why an inspection was accepted. Getting the terminology right is the easy part; being able to produce the qualification record, the calibration traceability and the procedure revision that applied on the day of the inspection is the part that decides audits.
Atlantis NDT provides NDT training and certification against ASNT SNT-TC-1A and ISO 9712, ASNT Level III consulting for written practices and procedure approval, inspection management software that holds qualification, calibration and procedure-revision evidence in recoverable form, and an asset integrity platform that binds inspection results to the asset they describe. Browse the full NDT glossary or ask a Level III directly.