Alloys are specified by design for mechanical characteristics, corrosion resistance, and temperature and pressure tolerance. Using an X-ray fluorescence (XRF) analyzer for positive material identification (PMI) can help prevent material mix-ups and component failures, which can lead to costly downtime, repair and replacement, and possible environmental and safety hazards.
Olympus' Vanta⢠hand-held XRF analyzer provides fast, definitive material confirmation when producing components, receiving alloy materials or installing pipes, valves, reaction vessels or welding, bolting and gasket joining materials. Vanta analyzers also provide:
- Rapid and definitive alloy confirmation and identification in critical installations.
- Optimum performance in harsh environments and high-temperature applications.
- Traceability to the field to meet API Recommended Practice (RP) 578 guidelines.
- Excellent performance on low-silicon (Si) applications to aid in the prevention of sulfidation corrosion.
Vanta analyzers are built for in-service inspection of high-temperature systems and hot sample surfaces up to 900 F (482 C) for maximum productivity in PMI applications including piping, valves, welds, components and pressure vessels. The analyzers are essential for:
- Helping ensure the correct alloy components are installed in critical locations.
- Complying with API RP 578 -- Material Verification Program for New and Existing Alloy Piping Systems.
- Detecting sulfidation corrosion susceptibility (API RP 939-C).
- Evaluating flow-accelerated corrosion susceptibility.
Hot testing tips: Si
Hot, in-service measurements of light elements such as Si in alloys are particularly challenging since they can take longer to measure than heavier elements such as chromium. Si makes up 27 percent of the earth's crust, making it a near-permanent fixture in most samples. Unfortunately, contamination from soil, dirt and debris has an adverse effect on XRF testing for Si. A small amount of Si on the surface of an alloy sample or on the window of the XRF analyzer can create an error when testing Si in low-alloy samples.
Contamination can also cause a high bias in measurement and result in a false conclusion that Si is abundantly present when there is none or much less than the reported value. With proper preparation, however, this can be overcome. The following tips are recommended:
- Use a zirconium oxide grinding wheel to remove paint, corrosion, scale and dirt.
- Do not make contact with a Si-contaminated surface or sample.
- Frequently test the analyzer against a reference sample (e.g., commercially pure iron) and a sample with a known small value (e.g., carbon steel) during testing to ensure no contamination is present.
Vanta hand-held XRF analyzers provide highly specific material chemistry to quickly and accurately identify alloy grades and help ensure correct alloy installation under even the harshest conditions.
For more information about Vanta hand-held XRF analyzers, visit www. olympus-ims.com/vanta.
