The Importance of Quality NDT Equipment for Houston Companies

Oil and gas infrastructure can suffer from high-temperature hydrogen attack (HTHA), where hydrogen dissociates and disbands within the steel under high temperatures, causing cracks and fissures. This is particularly concerning for refineries, and petrochemical plants in Houston, which is home to one-third of the nation’s energy jobs. Therefore, Houston-based producers need impeccable NDT equipment to efficiently and safely run operations. 

One of the answers to HTHA deviations for the Houston-based oil and gas industry is ultrasonic testing (UT) equipment. This nondestructive testing (NDT) technique has enough flexibility and probing prowess to achieve a successful inspection without dismantling a tested object. Technicians can receive a thorough profile of a design form and ensure it operates efficiently. This article will demonstrate why phased array ultrasonic testing (PAUT) can be the best choice for HTHA cracking in the Houston refinery and chemical sectors.

The Advantages of PAUT for Houston Oil and Gas Companies

Since Houston is a major energy hub, refineries and plants can face high HTHA rates. Houston chemical plants even experienced a series of fires in 2019, underscoring the need for robust safety and inspection measures. With that, PAUT is an advanced measure that can prevent catastrophic accidents in Houston. PAUT offers encoded scanning techniques which can reduce the probability for missing certain areas of a component. Also, the archived data can also be used for future review and comparison with new data from similar or other inspection techniques as the component ages. 

Example: With PAUT, a well-trained technician can apply an efficient and robust inspection strategy, combining multiple advanced ultrasonic examination techniques like TOFD, TULA, PAUT, and live TFM. 

Houston oil and gas operators  need flexible solutions to find all types of defects. With conventional ultrasonic means, the incidence angle and focal point remain stationary. As a result, technicians are less likely to find challenging flaws. Those same fixed points also cannot read angles or curvatures effectively, which prevents the detection of additional defects during the testing process. Further, HTHA flaws like methane voids may be narrower than the waves, escaping detection. As such, PAUT is a step above traditional ultrasonic scanning due to its diverse angle capabilities. 

Take note of the additional benefits PAUT offers:

• Prominent focusing depths
• Beaming shaping and customizations
• Linear scanning to achieve robust coverage
• Faster testing

Overall, PAUT will help Houston analysts find minuscule indications that may escape detection with other NDT techniques.

Creating Detailed PAUT Inspection Plans

Certain forms of HTHA cracking can remain hidden due to the infinitesimal size of the methane voids. These underlying voids can worsen over time and cause safety hazards that can injure personnel. Moreover, they can degrade the operational integrity of assets or halt operations altogether. 

Houston is home to many high performance refineries and chemical plants, and greater activity can yield higher rates of HTHA deformations. The bustling activity brings stress to valuable plant equipment. 

Luckily, a well-trained technician, carefully selected probes and a PAUT device with 64-active elements can help technicians find minuscule deviations in the form of micro-fissures or methane annuls. Time-of-flight diffraction (TOFD) complements PAUT because it assesses the beam’s flight intervals from the probe to the receiver, allowing the equipment to get a fixed reading on the orientation and flaw size. This will be a great help to any Houston facility looking to detect and assess HTHA  sooner rather than later.

TOFD also offers the following advantages when combined with PAUT:

• Very effective for the detection, characterization and sizing of embedded flaws
• Accurate through-wall sizing of far-surface cracks
• Rapid and robust technique for initial HTHA damage screening of base material and the heat-affected zone of welded regions.
• Effective to detect and size HTHA induced macrocracks

Still, TOFD has its shortcomings, as it cannot inspect thicker wall sections due to reduced beam quality. Therefore, technicians should apply a TOFD Ultra Low Angle (TULA), which can scan thicker welds and pinpoint smaller HTHA deviations. 

The total focusing method (TFM) is another vital tool during HTHA inspection because it provides a more refined characterization of discontinuities. Enhanced imaging is crucial in the Houston area, allowing technicians to capture underlying discontinuities that can lead to accidents. 

Although rare, Houston’s refinery and chemical plant  sector can experience dangers in the form of explosions, accidents, and fires. These hazards can harm human life and incur liability lawsuits. Advanced screening, however, gives manufacturers the edge in preventing dangers and promoting safety. The best PAUT equipment includes advanced focusing techniques that can process elementary A-scan signals “live” during the inspection, and generate improved UT image resolution for better characterization and sizing of challenging damage like HTHA.

Finding Quality NDT Equipment in Houston 

The Texas oil industry comprises roughly 42% of crude oil production in the United States, 24% of the nation’s natural gas production. As a result, the energy infrastructure in Texas undergoes strains more than other energy assets around the nation. With the added stress comes a higher chance of HTHA defects that can hamper operations. 

Due to the incessant demand, NDT equipment in Houston should have enough power to read minute indications before they morph into larger problems that can halt production efforts. HTHA aberrations can be common in petrochemical facilities, in addition to chemical plants and refineries. Detecting and assessing HTHA is only one example of how PAUT is useful for upstream, downstream, and midstream campaigns and can help oil and gas companies save money on maintenance costs and improve safety.

Zetec is a leading provider of PAUT equipment for the energy sector in Houston and around the world. Contact us today to get a tailored inspection plan and insight into the best HTHA solutions.