Gamma-Tech enhances its Non-Destructive Testing with Positive Material Identification service. Gamma-Tech’s on-site inspection and testing team has a highly sophisticated handheld / portable X-Ray Florescence (XRF) Spectrometer which can measure the chemical composition of the materials, non-destructively and accurately. The range of equipment available for undertaking Positive Material Identification (PMI) at Gamma-Tech is unparalleled. Positive Material Identification service is fast becoming an integral part of process safety management in the petroleum refining, petrochemical and electric power generation industries in Canada. Using X-Ray Florescence (XRF) instruments can provide elemental identification and quantitative determination without regard to form, size and shape. No samples need to be cut during PMI.
Gamma-Tech has inspection personnel to undertake incoming material inspection and provide on-site alloy verification for Quality control purposes.
PMI equipment includes: Portable X-Ray Florescence (XRF) Based Instruments XMet 3000TX.
Chemical Analysis Corrosion resistance, resistance to high temperature scaling and the strength of alloyed steels are all dependent on the chemical composition of the material. At present, fully detailed analysis of the chemical composition can be made at laboratory only. But as the samples can be as small as e.i. 5 x 5 x 3 mm, the test may be non-destructive if the sampling does not affect the function of the component.
If a verification of the alloy is sufficient and this can be achieved by less detailed analysis or perhaps by an estimate of the level of one or two alloying elements several non-destructive methods are available.
A requirement for PMI tests is more and more often seen in specifications for both high temperature alloys and stainless steels in petrochemical plants. As an example, the stainless steel piping systems for a refinery on an off shore installation in Norway were specified to be PMI-tested. A percentage of all welds and items from each heat of steel were tested to verify that pipes were alloy type 316 and not type 304.
Other areas for PMI are critical components and piping in chemical and pharmaceutical plants and in food production equipment.
If an audit on a new plant i.e.: made by the authorities or insurance inspectors, reveals that properly stamped identification is missing, PMI can verify that no alloy mismatch has occurred. As such, sampling for more extensive tests leading to repair and subsequent tests of the samples and NDT of the repair are avoided.
The NDT techniques offer a possibility to detect materials damage in an early stage and by this prohibit dangerous and costly failures.
Plants that are notoriously exposed to gradual degradation will be safer and live longer if the areas of highest degradation rate are located and possible damage repaired at an early stage.
Qualification of new plants and the documentation for it can be improved if alloy type and materials properties are confirmed by tests upon receipt or by testing during erection and assembly.
As for all NDT techniques, the method used requires both suitable equipment, detailed procedure specifications / instructions and qualified skilled personnel to perform the tests and evaluate the results. For this reason, it can be expected that the operators for these methods must be not only qualified by skills and experience but also through formal training and a stringent certification process.
