XIP: Process reliability despite interference radiation
In many industrial plants, weld seams on pipelines and vessels are regularly tested for integrity using X-ray or gamma radiation. The radiation emitted during these inspections can distort radiometric measurements even over long distances (up to 1.5 km). The consequences can be serious:
✦ Incorrect process control
Measurement deviations lead to unnecessary material additions or incorrect control actions.
✦ Production downtime
In critical processes, there is a risk of automatic shutdowns.
✦ Environmental impact
Emergency relief actions can release environmentally harmful substances into the environment.
✦ Increased costs
Manual monitoring, cleaning work, or even the replacement of plant components may be required.
Interference radiation impacts the measurement system
The graph shows how external radiation affects the process value (green line) without XIP: If external radiation increases, the process value (red) drops and becomes falsified. As soon as the external radiation is over, the process value recovers, but only slowly depending on the set time constant.
Why conventional protective measures are insufficient
Additional lead shielding can reduce background radiation but does not provide adequate protection against interference radiation. The effects of weld integrity inspections can impact measurements from any angle and distance making complete shielding practically impossible. Moreover, such solutions are expensive, heavy, and require significant maintenance.
The solution:
XIP function for radiometric measurements
X-Ray Interference Protection (XIP) automatically detects interference radiation and holds the last correct process value during weld integrity inspections. This ensures your measurements remain accurate and the process continues safely. Additionally, the XIP status can be transmitted via a digital output.
How does XIP work?
The function monitors the count rate of the measurement system and detects interference radiation based on two criteria:
- Factor criterion: If the count rate exceeds a defined threshold, the calculated process value is held until the interference radiation event ends.
- Sigma criterion: Detects even weak or distant interference radiation events (“soft NDT events”) through a statistical analysis of deviations in the count rate.
Both mechanisms can be individually configured to optimally adapt to your process.
✦ Maximum process reliability:
Prevents incorrect control actions or unnecessary shutdowns.
✦ High product quality:
Avoids overfilling or underfilling.
✦ Cost savings:
Reduces production downtime and manual interventions, while optimizing the use of process additives.
✦ Environmental protection:
Minimizes emergency relief events and resulting emissions.
Conclusion
With XIP, your radiometric measurements remain reliable even during regular weld integrity inspections. In practical terms, this means fewer production interruptions, lower costs, and enhanced operational safety and environmental integrity.