Special to Pipeline & Gas Journal
Volvo pipelayers were used on both sides of the border to allow gas to flow from France to Belgium for the first time.
As well as responding to increasing demand for gas in Belgium’s West Flanders region, the new pipeline will feed gas to northwest Europe. Located between Alveringem, near the French border and port of Dunkirk, and Maldegem, east of Bruges in East Flanders, the existing infrastructure could no longer cope with growing demand from new housing and small and medium-sized enterprises starting up in the area.
On the French side of the border, responsibility for connecting Belgium to the French network fell to French grid operator GRTgaz, and a Volvo PL4809D rotating pipelayer was used on the project by French pipeline specialist SPAC, a subsidiary of the Colas Group.
The Belgian side is the responsibility of Fluxys Belgium NV, the independent operator of Belgium’s natural gas transmission grid and storage infrastructure, which transmits natural gas across Belgium to distribution system operators, power stations and major industrial customers. The 36-inch pipe runs for 74 km and the joint operation enables the transmission of 8 Bcm of natural gas between the two countries for the first time.
Pipeline contractor A. Hak Leidingbouw, specialists in large-diameter pipelines, worked on a 20-km section using two Volvo PL4608 rotating pipelayers. Each 18-meter section of pipe weighs about six tons, but this is not a problem for the PL4608s with its 80-ton tipping capacity. The aim was to complete about 1,000 meters – or 50 welds – daily alongside Dutch subcontractor, specialists Visser & Smit Hanab NV.
Hak was the first pipeline contractor in the world to purchase the Volvo equipment – six machines – in 2009. Loe Steenbergen, in charge of equipment purchase and rental for the group, has worked on pipelines across Europe for 11 years.
He said he opted for the this particular equipment because he liked “the concept of the upper structure rotation, and the machine’s good lifting table,” adding, “They perform like machines with a 90-ton tipping capacity, even if it says 80 tons on paper.”
There are various crossings to contend with en route. Roads are often crossed by laying down special surface-protection mats, but other methods are required for rail or water. Here, he said the PL4608 offered an advantage as it can be loaded onto a transporter and moved without the need for disassembly. Once a tie-in was complete, the machine could be quickly transported to the next one, saving time and money.
“Tie-ins cost around €10,000 [$11,200] each,” said Steenbergen. “Savings on transportation costs alone are significant.”
Operators, too, have warmed to the pipelayers – these units currently have about 6,000 hours on the clock compared with less than 2,000 for the company’s sidebooms, purchased at the same time.
“We use excavator operators as they adapt quickly to the pipelayer,” said Steenbergen of the PL4608s, used for tie-ins and during the welding and bending processes. When feeding the bending machine, the upper structure rotation enables the machine to swing the pipes into position with no disruption to conditions underfoot, which is not possible with a conventional sideboom pipelayer.
Operator Marcel Wiehink has seven years of experience with pipelayers and is licensed to operate sidebooms and crawler cranes.
“I like the flexibility of the swing,” he said. “When there are over-crossed pipes, I can easily lift and reposition them on the other side.” He said he also appreciates the single straight travel pedal because it leaves his hands free to control the boom and winch.
The abrasive, sandy conditions in the Netherlands, where these machines do most of their work, are renowned for damage to wear parts. On this site, which is extremely sandy, hundreds of tons of wood chips have been used along the right-of-way to facilitate machine movement and to support local farmers. The biodegradable chips help limit the amount of sand mixed in the soil once the land is reclaimed for agricultural use.
As with any pipeline, archaeologists were given access to the site before work began to establish what, if any, treasures might be unearthed. However, given the geographic location and the region’s history, both historical records and onsite detection methods determined the need for specialist demining operations. Archaeological studies were also conducted to ensure that any buried, unexploded munitions – mainly remnants of World War I – were safely recovered.
The sustainable approach used by Fluxys in the preparation and construction of pipelines covers safety issues as well as environmental and ecological factors. It ensures that once the project ends, the land can be reinstated for farming.