pressuretest

Pressure test, or pressure testing, is a verification method in which a system, component, or vessel is subjected to a controlled pressure higher than its normal operating conditions to assess structural integrity and leak-tightness. The test helps identify weak points, flaws, or joints that could fail in service. It is used across industries such as oil and gas, chemical processing, water and wastewater, HVAC, and aerospace, for pressure vessels, pipelines, tanks, boilers, and heat exchangers.

Two primary methods are used: hydrostatic (liquid) and pneumatic (gas). Hydrostatic testing fills the system with water or another incompressible liquid and gradually increases pressure to the specified level, reducing energy release risks and facilitating leak detection. Pneumatic testing uses air or inert gas when liquids are impractical; it carries greater risk due to gas compressibility and requires stringent safety measures.

Typical procedures involve isolating the test section, purging air, filling with the test medium, and pressurizing to the required level while monitoring for leaks, deformation, or permanent set. The pressure is held for a defined duration, then depressurized safely. Acceptance criteria usually include no detectable leaks, no unacceptable deformation, and conformity with design and code requirements. Documentation of test results is standard practice.

Standards and codes govern pressure testing, including guidelines on test pressure, duration, and acceptance criteria. Examples include ASME BPVC for vessels, API 598 for valves, and various EN/ISO standards. Safety considerations are paramount, with appropriate equipment, containment, and procedures to mitigate the risk of rapid energy release.

In software, pressure testing is sometimes used informally to describe load or stress testing to evaluate performance under high demand, though more precise terms are load testing or stress testing.