Ventil’s In-Situ Testing Technology

Pressure Relief Valves (PRVs) are essential safety devices that protect people, equipment and processes from dangerous overpressure events. Ensuring these valves operate at their correct set pressure is critical for plant safety, regulatory compliance and asset reliability.

Traditionally, PRV verification has relied on bench testing, which requires valves to be removed, transported to a certified workshop, tested, refurbished if required, and reinstalled. While effective, this approach can be time-consuming, costly and disruptive - often requiring process isolation, lifting equipment and planned shutdowns.

In-situ testing technology is changing this maintenance model by allowing PRVs to be accurately tested while remaining installed. This enables operators to verify valve performance with less disruption, reduced risk and improved efficiency.

Minimising Downtime and Maintenance Disruption

One of the greatest advantages of in-situ testing is the ability to assess PRV performance without removing the valve from service. Modern systems can perform hot testing while the process remains operational or cold testing under isolated conditions when required.

By avoiding valve removal and shutdown activities, facilities can reduce production losses, particularly in continuous-process industries where downtime can have significant financial impacts.

Improving Compliance and Asset Integrity

In-situ testing provides valuable performance data to support risk-based maintenance strategies and regulatory compliance. Using controlled lifting force, load measurement and acoustic monitoring, advanced systems can accurately determine a valve’s actual opening point while installed.

The resulting test records provide traceable evidence of valve condition and functionality, supporting compliance with recognised standards including:

• ASME Section XIII
• ASME PTC 25
• API recommended practices and requirements
• ISO 4126
• European Pressure Equipment Directive (PED)

This data helps operators make informed maintenance decisions and strengthens audit readiness.

Reducing Mechanical and Safety Risks

Removing large PRVs from difficult locations can require cranes, scaffolding, rigging and extensive manual handling. These activities introduce risks such as damage to valve seats, sealing surfaces and connected pipework.

In-situ testing eliminates much of this intervention. By keeping the valve installed, system integrity is maintained, maintenance exposure is reduced and the risk of installation-related issues is minimised.

Delivering Cost and Efficiency Benefits

Beyond avoiding downtime, in-situ testing reduces costs associated with transportation, workshops, lifting equipment and labour. Maintenance teams can test more valves within the same timeframe, improving inspection coverage and asset visibility.

PreVenTest Nexus: Advancing In-Situ PRV Testing

The PreVenTest Nexus Auxiliary Lift Assist Device (ALAD) provides a modern solution for testing spring-operated PRVs in-situ. Suitable for steam, gas and liquid applications, the system combines precision force application, advanced software and a database of more than 4,000 seat-size configurations from leading PRV manufacturers.

By accurately measuring valve response under operating conditions, Nexus helps operators verify performance quickly, reliably and with minimal operational disruption.

As industries continue to prioritise safety, compliance and efficiency, in-situ testing is becoming a strategic tool for improving PRV reliability, reducing lifecycle costs and strengthening overall asset management.

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