Non-Destructive Testing — Positive Material Identification
On-site XRF and OES alloy verification — fast, non-destructive and fully traceable. Confirm material grade, prevent costly mix-ups and satisfy third-party inspection requirements before fabrication or commissioning.
Why PMI Matters
Material mix-ups are one of the leading causes of in-service failures in process piping and pressure equipment. A single wrong-grade fitting installed in a high-temperature or corrosive service can lead to catastrophic failure — and incorrect material is often visually indistinguishable from the correct one.
PMI closes this gap. It gives you chemical composition data — on-site, in minutes — so you know what you actually have, not just what the paperwork says.
Major codes including API 578, ASME PCC-2 and client specifications for critical process plants mandate PMI programmes specifically because of this risk.
Carbon steel fittings installed in stainless service. Wrong grade valves accepted on a high-pressure line. Weld consumable does not match base material. Mill certificate does not match physical part. These happen — and PMI catches them before they become failures.
Every component's elemental composition confirmed before installation. Full traceability record attached to the project file. Third-party inspector sign-off obtained without delays. Client and regulatory confidence established from day one.
Verification Capability
PMI provides elemental composition data for any metallic component — from incoming inspection to in-service plant checks.
Verify that pipes, fittings, flanges, plates and forgings are the correct alloy grade — SS 304, 316, 316L, Duplex, Inconel, P91, Chrome-Moly and hundreds more.
Quantitative weight-percent readings for key elements — Cr, Ni, Mo, Mn, Si, Nb, Ti, Cu, Fe and more — compared against ASTM / ASME material standards.
Identify wrong-grade material in mixed stock, at goods inward inspection, or after fabrication — before costly rework or in-service failure occurs.
Generate a permanent PMI record tied to component identity (tag, heat number, location) for project documentation, regulatory compliance and audit purposes.
Confirm weld deposit chemistry matches procedure requirements and base material — critical for dissimilar metal welds and high-alloy applications.
Verify material identity of existing plant components during turnarounds, maintenance or before re-rating — without removing or damaging the component.
Non-destructive: XRF PMI leaves no mark on the component surface. OES leaves a small spark spot (typically <1 mm). Both methods are accepted under API 578 and most client PMI programme specifications.
PMI Techniques
We operate both techniques. Our technician recommends the appropriate method based on your material type, required elements and site conditions.
| Parameter | XRF (X-Ray Fluorescence) | OES (Optical Emission Spectrometry) |
|---|---|---|
| Method | X-ray beam excites surface atoms; fluorescence measured | Spark discharge excites surface; emitted light analysed |
| Surface Effect | Fully non-destructive — no mark | Tiny spark spot (~1 mm) — negligible in practice |
| Light Elements | Cannot detect C, N, S reliably | Detects Carbon — critical for L-grade (304L, 316L) confirmation |
| Speed per Reading | 5–30 seconds | 10–30 seconds |
| Portability | Handheld — excellent for confined spaces, at-height, field | Portable — requires stable contact; best on flat surfaces |
| Best For | General alloy ID, painted/coated components, most site PMI | Carbon content confirmation, L-grade vs standard grade distinction |
For critical applications requiring Carbon content verification (e.g. confirming 316L vs 316), we recommend OES or a combined XRF + OES approach.
Alloy Coverage
Our XRF analyser carries a library of 300+ alloy grades. Common grades we test include:
| Material Family | Common Grades | Key Application |
|---|---|---|
| Austenitic Stainless Steel | SS 304, 304L, 316, 316L, 321, 347 | Process piping, tanks, vessels |
| Duplex / Super Duplex | 2205 (UNS S31803), 2507 (UNS S32750) | Offshore, chemical, high-chloride service |
| Chrome-Moly (Cr-Mo) Steels | P11, P22, P91, P92, F11, F22 | High-temperature boiler, power plant piping |
| Nickel Alloys | Inconel 625, 718, Incoloy 825, Hastelloy C-276 | High-corrosion, high-temperature, aerospace |
| Titanium Alloys | Grade 2, Grade 5 (Ti-6Al-4V) | Chemical, marine, aerospace |
| Carbon & Low-Alloy Steel | A105, A106, A333, A350, A182 | General piping, pressure parts, flanges |
| Copper Alloys | Cu-Ni (90/10, 70/30), Brass, Bronze | Marine, heat exchangers, instrumentation |
Don't see your alloy? Contact us — our library covers virtually all engineering alloys. Custom calibrations available on request.
Applications
PMI is used across the full lifecycle of process equipment — from procurement through fabrication, construction and plant operation. API 578 defines three principal application scopes:
Our Process
PMI is one of the fastest NDT services — a full scope can often be completed in a single shift. Here is what to expect.
We review your isometrics, line lists or component schedule to define the PMI scope — which components, which service criticality, what acceptance criteria (API 578 or client spec), and the percentage of items to be tested.
Painted or heavily oxidised surfaces are lightly prepared to bare metal at the test spot only. Each component is tagged or referenced against the component list. Test location is marked and photographed where required by the client spec.
XRF or OES reading is taken. The analyser instantly displays elemental percentages and compares them against the target alloy grade — pass / fail result shown on-screen within seconds. Multiple readings per component taken where required.
Full PMI report issued with component identification, test location, elemental readings, target grade comparison, pass/fail status and technician certification. Delivered same day or within 24 hours depending on scope size.
Codes & Standards
Our PMI programmes are designed to meet all major industry standards for material verification. Our reports are formatted to satisfy client specifications and third-party inspection requirements.
Our PMI reports include component ID, heat number (if available), test location, full elemental wt-% readings, target grade comparison and technician qualification — accepted by Lloyd's, Bureau Veritas, TÜV, SGS and IBR inspectors.
Our XRF and OES instruments are calibrated against certified reference standards and maintained within manufacturer specifications. Calibration certificates available with every report on request.
PMI readings and report sign-off performed by qualified NDT professionals with documented experience in material identification — not junior site helpers.
FAQ
No. XRF is completely non-destructive — it directs an X-ray beam at the surface and measures the fluorescent energy returned. There is no contact mark, no spark and no surface damage. Components can be tested and immediately returned to service or installed without any remediation of the test spot.
XRF alone cannot reliably measure Carbon content (a light element). To distinguish 316 from 316L you need OES (Optical Emission Spectrometry), which does measure Carbon. We offer OES specifically for L-grade confirmation. For general alloy ID where Carbon is not the critical differentiator, XRF is sufficient and much faster.
XRF PMI is very fast — typically 30 seconds or less per reading. A single technician can realistically test 200–400 individual components per shift depending on access, surface preparation requirements and documentation level. For large new-construction scopes, we can mobilise additional technicians to meet your schedule.
Our reports include: project and client details, date and location, component identification (tag, spool number, size, heat number), test method (XRF/OES), instrument make/model and calibration status, elemental weight-percent readings, target alloy grade, pass/fail result per component, and technician name and qualification. Reports are issued as PDF and can be provided in your format template on request.
API 578 provides industry guidance recommending PMI for alloy piping and pressure equipment in process services. Many client EPC and owner specifications mandate 100% PMI on all alloy components in certain service categories (e.g. sour service, corrosive, high-temperature). Even where not mandated, PMI is best practice for alloy materials — the cost of testing is negligible compared to the cost of a mix-up failure.
Yes. Our handheld XRF analyser is compact and battery-operated — it can be used in confined spaces, at height on scaffolding, in live plant environments and in any orientation. If additional access equipment is required, we coordinate with your site team in advance.
Request a Quote
Send us your component list or line list and we will respond with a full PMI scope and quotation within one business day. All enquiries handled by our technical team — not a call centre.