Refinery & Petrochemical

Corrosion Mapping

Refinery & Petrochemical

MISTRAS has provided comprehensive NDT services and solutions to the refining and petrochemical industries for more than 40 years. Beginning with construction, through operation and maintenance, MISTRAS offers an array of monitoring, inspection, and data management services - all of which ensure the integrity of your operating assets.

Code and regulatory compliance is met thanks to Traditional NDT inspections, the data from which is managed by our Plant Condition Management Software (PCMS®) with RBI capabilities. Global inspections to ensure the safe and efficient operation of equipment via advanced NDT techniques (Acoustic Emission, Automated Ultrasonics, Computed Radiography, Alternating Current Field Measurement and Long Range Ultrasonics) are also offered. The data is evaluated using our Fitness for Service software, which determines the safe operating parameters of your equipment.

MISTRAS Rope Access Services for the Petrochemical Industry Video

A few of our unique approaches include:

Tube Inspection

There can be fewer more risky industries and environments than those involving petrochemicals and power generation. Harsh, challenging and in constant danger of cataclysmic incidents, the focus on health and safety is understandably high. Harmonious working between man and materials is essential and, whilst much human endeavour can be observed and regulated, inert equipment is always prone to the unexpected. Minimising risk is very much a way of life.

Both industries rely heavily on arterial infrastructure; tubes of all dimensions and uses, being especially dependent on heat exchangers and boilers. Often tubes are bundled together making even visual inspection difficult or hazardous; in many cases normal ultrasonic and radiographic inspections fail to achieve results to an acceptable standard. Allied to these safety issues are economic factors relating to downtime costs and production shutdowns, frequently measured in weeks. Risky reliance on visual inspection and destructive testing of many small-bore tubes has led to past uncertainty and potentially expensive decisions as to whether and when to repair or replace.

Remote Field Eddy Current Technique (RFT)

This process is well adapted to the inspection of small-bore ferromagnetic tubes such as carbon steel. Using electromagnetic techniques this is now the industry standard inspection for boilers and heat exchangers due to its low frequency (typically 50-1000Hz). The probe consists of two coils in a sen-receive configuration which are inserted into the tube. The energised exciter coil transmits a signal to the detector coil located some distance away. This signal passes through to the outside tube wall returning to arrive at the detector coil. With wall thinning there is less shielding hence the return time (greater phase) and attenuation (greater amplitude) is shorter. Phase and amplitude traces are generated as the probe is pulled through the tube as recorded data identifies the metal loss. Flaw sizing is also possible with RFT enabling depth, length and circumference to be accurately calibrated.

Eddy Current Technique (ECT)

Another electromagnetic technique which has been adapted for small-bore tubing manufactured from non-ferrous metals such as stainless steel, titanium, copper, brass, coppernickelalloys and Inconel. ECT is based on the principles of electromagnetic induction and uses a test coil through which is passed an alternating or varying current known as the primary field. This induces varying secondary electromagnetic field in the test object, known as an eddy current. In this way characteristic changes in the test object such as conductivity, permeability and geometry cause the eddy current to change which is reflected to the test coil. A number of frequencies in differential and absolute modes detect gradual wall loss. Multi-frequency is essential to differentiate between defects and metallic deposits and also enables defects under support plates to be detected.

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