Years of research and development preceded the installation of two capacity-boosting loops on an existing pipeline owned by TransCanada PipeLine Limited in Alberta, Canada. Included in the field test were:
- A 1.6-km loop of 36-in. X-120 pipe developed by ExxonMobil; and,
- A 2.0-km loop of 36-in. X-100 pipe developed jointly by TransCanada and BP.
In the pipeline industry, numerical designations identify the specific yield strength of pipe. The X-120 pipe developed by ExxonMobil, for example, has double the yield strength of X-60 allowing the same pressure capacity to be achieved with half the weight of pipe.
The field test near Slave Lake in Alberta supplied the three majors – ExxonMobil, TransCanada and BP – with a remote setting to test their new pipe using welding technology supplied by Houston-based CRC-Evans. Engineers from CRC-Evans served on the R&D teams for both the X-100 and X-120 program, and the field test marked the debut of new automated welders and techniques developed by CRC-Evans.
“As field trials go, they don’t get any better than this. Not only did we hit our estimated production rates, but we also completed both loops with an extremely low repair rate. The majors got exactly what they were looking for: a field confirmation that opens the door to commercial use of X-100 and X-120 pipe,” said Brian Laing, President of CRC-Evans Automatic Welding.
Laing noted that no special accommodations were made for the X-120 and X-100 loops. “If you’re out to dispel myths about a new pipe, your field test should duplicate actual working conditions. We used conventional contractors working in a remote location during a Canadian winter – and the X-120 and X-100 sailed through it all with flying colours,” Mr Laing said.
Two different welding technologies were employed during the field test:
- The ExxonMobil sponsored X-120 loop marked the debut of a new CRC-Evans automated welding “˜bug’ dubbed the P-260 and of a new wire developed by ExxonMobil for welding X-120. Working in pairs on the outside of each 40 ft section of pipe, the computer-controlled P-260s use pulsed-gas metal arc welding. Four P-260 welding stations were employed during the four-day test, with crews completing an average of 41 welds a day with an overall repair rate of only 1.41 per cent. “Prior to the field test, everyone would have been ecstatic with a repair rate of 10 per cent. The P-260 was everything we designed it to be,” Mr Laing said.
- CRC-Evans used a combination of conventional and tandem welding technology to complete the BP-sponsored loop of X-100 pipe. Developed for the pipeline welding industry by Cranfield University in the United Kingdom, tandem welding doubles the welding speed of conventional single-arc processes. CRC-Evans used its P-600 welding systems to add the loop of X-100 pipe to the existing TransCanada line, and Mr Laing noted that the computer-controlled P-600s achieved a lower-than-expected repair rate.
Mr Laing said smiles were the order of the day at the end of the field test. “I know that our design engineers enjoyed their collaboration with ExxonMobil, TransCanada and BP, and the field test demonstrated what can be achieved when highly skilled teams share a common goal. These majors put their trust in us, and CRC-Evans delivered,” Mr Laing said.
CRC-Evans Automatic Welding manufactures automated welding systems used in the construction of pipelines. The company is a subsidiary of CRC-Evans Pipeline International, a leading provider of specialised equipment and services for the construction, rehabilitation and maintenance of pipelines. CRC-Evans manufactures pipeline construction equipment and automatic welding systems, and provides field joint coating, weighting, heat treatment, and inspection services. Based in Houston, CRC-Evans maintains offices in North America, Europe, and the Middle East.