HMT Inspection technicians are thoroughly trained and qualified in accordance with the HMT Inspection procedure for qualification and certification of Nondestructive Examination Personnel which is written in light of the guidelines set forth in ASNT Recommended Practice SNT-TC-1A 2006 edition.
Advanced NDE Inspection Equipment Includes:
- Long Range Ultrasonic Testing (LRUT ), on piping using a Guided Ultrasonics Limited (GUL) G4mini system
- Medium Range Ultrasonic Testing (MRUT), performed by Electromagnetic Acoustic Transducer (EMAT)
- Phased Array Ultrasonic Testing (PAUT)
- 3D MFL Mapping
- Automated Ultrasonic Crawler
- Tank Bottom SLOFECTM Scanner
- Tank Bottom Magnetic Flux Leakage (MFL) Scanner
- Helium Mass Spectrometer Leak Testing
Long Range Ultrasonic Testing (LRUT)
Long Range Ultrasonic Testing is performed on piping, using a Guided Ultrasonic Limited (GUL) G4mini wave system. Guided wave tests can be performed on piping from 2” diameter up to 96” diameter and very long length to inspect corrosion type defects. For piping of nominal wall thickness, gaseous product, without welded supports the distance of one single examination, can exceed 300’ in each direction from the transducer ring.
Medium Range Ultrasonic Testing (MRUT)
Medium Range Ultrasonic Testing, performed by Electromagnetic Acoustic Transducer (EMAT) is typically performed by EMAT (Electromagnetic Acoustic Transducer). Guided waves, shear waves, shear-horizontal waves, surface waves, and longitudinal waves, travel outward from the transducer location, while inspecting corrosion defects in in hard to reach places. Such applications include, but not limited to, areas beneath saddle supports on piping and vessels, into the annular ring of a storage tank from the outer protrusion, and many similar circumstances of limited access.
Phased Array Ultrasonic Testing (PAUT)
Phased Array Ultrasonic Testing is an ultrasonic method using an array of piezocomposite elements which are timed (or phased) to send ultrasonic energy which will react together forming the beam of choice. PAUT is used in weld quality testing in lieu of radiography, crack or defect sizing, corrosion mapping, composite materials bond testing, as well as many other applications. For ASME B31.3 and B31.1 PAUT can be used alone for weld quality examinations. For ASME Section VIII (Division 1 / Division 2) PAUT can be used in parallel with TOFD (Time of Flight Diffraction) for weld quality examinations. A similar PAUT/TOFD method can also be utilized for API 653 Annex U new tank construction projects for testing welds in lieu of radiography. PAUT examinations provide 3-dimensional flaw sizing giving a position across the part’s surface, a length of defect, as well as a depth and height size of a defect. The data from a PAUT examination is stored and can be easily transferred with internet access for level 3- or third-party review.
3D MFL Mapping
HMT Inspection offers the latest in floor mapping technologies, the 3D MFL (Magnetic Flux Leakage). This technology improves accuracy compared to traditional MFL techniques and provides flexibility in reporting and analysis.
Automated Ultrasonic Crawler
HMT Inspection offers an automated crawler for performing ultrasonic line scans. The system is highly effective for providing continuous ultrasonic thickness data on tank shells and storage spheres.
Tank Bottom SLOFEC™ Scanner
HMT offers reliable tank bottom scanning for fiberglass reinforced polymer coated tank bottoms (FRP). The Saturation Low Frequency Eddy Current (SLOFEC™) tank bottom scanner has the capability to induce sufficient current (flux) to inspect through coatings up to 300 mils thick by using an electro-magnet system. Because eddy current probes are used, the scanner (using the phase angle), can determine whether the defect is product-side, soil-side or both.
Additionally, the eddy current probe is sensitive enough to quantify soil side defects with minimal coating disturbance. The SLOFEC™ technology has the ability to indicate if the coating thickness has changed beyond the calibration range. This precludes problems with sensitivity errors due to coating thickness changes.
The SLOFEC™ tank bottom scanner can handle the “prove-up” of detection areas on the soil side after calibration, and quantify, with sufficient accuracy, in order to make repair decisions. This initial calibration and “prove up” minimizes coating destruction.
Key Benefits of the SLOFEC™ Scanner Include:- Ability to scan through coatings that are up to 0.300” thick and are reinforced with fiberglass
- Minimizes the need to remove coating to accommodate bottom inspection and / or Ultrasonic “prove-up”
- Does not require Ultrasonic “prove-up” of located defects
- The capability to indicate which side of the plate the defect is located
- Provides accurate depth information and thus remaining wall information on located soil side corrosion pits
- Operates at speeds that are comparable to current MFL equipment
Tank Bottom Magnetic Flux Leakage (MFL) Scanner
HMT offers the latest in NDE equipment for tank bottom inspection including the Magnetic Flux Leakage (MFL) bottom scanners. MFL bottom scanning is also known as MFE (Magnetic Flux Exclusion / Evaluation). MFL is the “best” method to evaluate a tank bottom condition quickly and cost effectively.
HMT’s bottom scanner is a steerable motorized corrosion detection instrument used in aboveground storage tanks to detect metal loss due to corrosion. MFL technology induces a magnetic field into the steel plates and then evaluates any disturbance in the magnetic field. When the magnetic field is disturbed, possible metal loss (either product side or soil side) has occurred and must be evaluated, or “proved-up”. The HMT bottom scanner features “stop on defect” functionality. When metal loss is detected the machine automatically stops, thus reducing human error resulting from missing a screen signal. This facilitates direct marking of the defect positions on the bottom plate surface for further investigation. To address smaller areas in which the larger MFL bottom scanner does not fit, HMT Inspection offers a motorized MFL Mini-Scanner and MFL Manual Scanner.
Post-scan, the inspection reports generate a full fingerprint of the tank bottom. These reports include identification of which side where the defect is located and using an “x”, “y” coordinate system, specific locations on the individual plate and its depth and remaining plate thickness. These reports highlight all areas requiring repair, assisting in establishing corrosion rates and next inspection intervals per API Standard 653.
Key Benefits of the Magnetic Flux Leakage (MFL) Include:- Evaluates tank bottom condition on bottom plates of ferrous material
- Quick, cost effective process and does not require couplant - “dry application”
- Steerable fast motor driven scanner
- Features “stop on defect” functionality
- Ruggedized touch screen technology for ease of use in the storage tank environment
- Full sized MFL Scanner, motorized MFL Mini-Scanner and MFL Manual Scanner available
Helium Mass Spectrometer Leak Testing
HMT Inspection offers Helium Mass Spectrometer Leak Detection services. HMT Inspection utilizes a Varian 959 Porta-Test Leak Detector with Macro Torr configuration which provides high test pressure capability and is excellent for fast response sniffing applications. This equipment is capable of 1 X 10 -9 atm cc/sec sensitivity, as required by ASME code for detector probe and tracer probe techniques.
HMT is capable of performing leak detection services on single bottom aboveground storage tanks (AST), double bottom ASTs, floating roof pontoons, heat exchanges, process piping, pressure vessels, underground storage tanks, underground pipelines, vacuum units and roof drains.
The use of helium as a tracer gas is advantageous because it is non-flammable, inexpensive, and it quickly diffuses through small leaks. In addition, it is non-reactive with other chemicals and easily permeates through the Earth and asphalt. Due to its minute molecular size and its low concentration in the atmosphere (5ppm), very small leaks may be detected. The use of the helium method enables the location of leaks up to 15 feet below ground. The Varian 959 Port-Test Helium Mass Spectrometer is only sensitive to helium; therefore eliminating false indications due to the presence of any other gases.