SGS Industrial Services (Geneva) has carried out phased array inspection in Nigeria for Daewoo E & C Co. Ltd. (Seoul) at the Gbaran Ubie Integrated Oil & Gas Project. Phased array ultrasonic inspection is one of the latest weld inspection methods and offers significant technical advantages for weld testing.

Phased array is an advanced nondestructive testing (NDT) method, which reveals defects hidden inside a structure or weld by testing the structural integrity. This new ultrasonic testing technique is based on generating and receiving ultrasounds. Instead of a single transducer and beam, phased arrays use multiple ultrasonic elements and electronic time delays to create beams by constructive and destructive interference.

In early 2008, Daewoo E & C Co. Ltd. was awarded the contract to construct a gas plant for the Gbaran Ubie Integrated Oil & Gas Project in Nigeria. In order to ensure high quality construction work, Daewoo asked for the support of SGS Industrial Services, the only company in Nigeria offering phased array inspection services.

Daewoo E & C Co. Ltd. chose phased array inspection as it offers significant technical advantages for weld testing over conventional ultrasonic testing methods. Phased array generates multiple ultrasonic signals within nanoseconds, which produce controllable angles, focus depths and wide coverage of an inspection point. Further advantages include excellent repeatability, increased inspection speeds, more accurate results and the ability to inspect complex geometries. Furthermore, phased array inspections are much safer to operate within a working environment, compared with NDT methods that use X-rays and gamma rays for detecting imperfections.

In May 2008, SGS Industrial Services provided a team of five experts to carry out phased array testing on the Gbaran Ubie Integrated Oil & Gas Project, scheduled to take 15 days of man power.

The project comprised two phases. The first phase involved the phased array inspection of 155 joints of heavy wall line pipes and the second phase included the follow-up inspection of 300 joints that were recently welded. The priority objective of SGS’ phased array testing was to inspect the welds for defects and to provide a reliability report.

The successful completion of SGS’ work resulted in the contract with SGS Industrial Services being extended until the Gbaran Ubie Integrated Oil & Gas Project in Nigeria is completed.

To successfully perform phased array in Nigeria for the first time was a notable event for SGS, as a major provider of advanced technologies to the oil and gas sector, whose objective is to introduce cutting-edge technology into the country. As provider of a comprehensive range of NDT solutions, SGS has a worldwide track record in new construction, pipeline installation and in-service inspection and expansion projects.

SGS Industrial Services
+31 181 693663
www.sgs.com/ndt

Benefits

Phased array generates multiple ultrasonic signals within nanoseconds, which produce controllable angles, focus depths and wide coverage of an inspection point.

It offers excellent repeatability, increased inspection speeds, more accurate results and the ability to inspect complex geometries.

Phased array inspections are much safer to operate within a working environment, compared with NDT methods that use X-rays and gamma rays for detecting imperfections.