One way that companies have addressed the corrosion challenge is by using high-density polyethylene (HDPE) pipe. HDPE’s corrosion resistance to produced water has been proven over many years of in-system service. However, using HDPE pipe comes with its own challenges, primarily because of its traditional joining method, butt fusing. Fitting and valve intense areas make the fusion process difficult and cumbersome, and this process can also be compromised by environmental conditions. The Victaulic system for HDPE is a safer, more efficient and more reliable solution.
In contrast, the Victaulic HDPE system installs 10x faster than a traditional fusion joint and can reduce construction time by 3 – 4 weeks on large projects. Victaulic couplings are ideal for use in close and confined spaces and, because they minimise disruption to the jobsite, can also be utilised in environmentally sensitive areas. Another noteworthy feature of Victaulic couplings is that they are not affected by contaminants or water on the pipe surface, so they can be installed in any weather. Finally, because they can be assembled using simple hand tools, Victaulic-employed professionals can train a crew on proper installation procedures within a matter of minutes.
Mechanical pipe joining in the field
Using the Victaulic system for HDPE on SWD systems can deliver installation efficiencies that truly pay off, as Crestwood Midstream Partners LP discovered while constructing its new Gondor facility in McKenzie County, North Dakota, US.
Permitted to accept up to 50 000 bpd of produced water, the Gondor facility features two wells, two separators, two oil storage tanks, and 10 produced water storage tanks across nearly three acres. When Crestwood began making decisions about how the SWD system would be constructed, three options were considered for the piping: stainless steel, fibreglass, and HDPE.
“HDPE was the best choice from a cost, constructability and longevity perspective,” noted Mark Donnelly, a senior project manager at Crestwood. “Gondor is compatible with HDPE because of the way our system is laid out. There is a continuous inlet flow through the pipes that helps keep them warm, so even when we get those really cold North Dakota days, the cold won’t settle into the pipes.”
Construction on the Gondor SWD was planned to begin in the summer of 2019, well in advance of a contractual obligation to operate at partial capacity by 1 October 2019. As Crestwood’s producer customers continued to forecast growing produced saltwater volumes, it was imperative for Crestwood to identify an efficient option in order to keep the project under budget and manage the project’s tight construction timeline demands.
“That’s where Victaulic came in,” Donnelly said.
Victaulic’s vertically integrated prefabrication solutions promised to deliver major productivity gains and labour efficiencies on the jobsite. In addition, their in-house Virtual Design & Construction (VDC) team worked with Crestwood’s engineering contractors to draft drawings for the Victaulic scope of work, consisting of 2-12” HDPE and internally plastic-coated carbon steel piping systems. Once completed, the design was imported into the overall project model and approved by Crestwood’s internal construction team.
Upon approval, Victaulic utilised one of its fabrication shops to fabricate, assemble, and ship the mechanical piping to the jobsite. Using prefabricated parts is up to four times more productive than field fabrication, and twice as much work can be completed per manhour. On the Gondor project, the combination of Victaulic’s prefabricated HDPE spools and onsite fit-ups using Victaulic HDPE couplings required virtually no rework in the field.
Donnelly was impressed by Victaulic’s speed. “The way Victaulic’s project timeline was advertised to me was ‘three or four days to pipe up the entire tank farm once the spools arrive.’ If we had gotten just a typical contractor out there, cutting and welding or doing HDPE fuses, it probably would have taken them three weeks to do that number of fittings.”
“Victaulic’s prefabrication solution was a true time-saver, and it helped us meet our customer’s date,” Donnelly continued. “Once our engineers finished the new tank farm model and sent it over to Victaulic, it was a pretty seamless process for us.” Victaulic immediately went to work, creating isometric and fabrication drawings, and building the spool pieces.
On installation day, the joints were installed with minimal effort and maximum speed: 10x faster than fusing and flanging. The fabricated spools eliminated the need for field fabrication, removing field cuts and joint-by-joint assembly on site. Additionally, the Victaulic system eliminated challenging fitting-to-fitting fuses, as well as vertical and overhead fusing—virtually impossible tasks. The speed with which the facility piping was erected was astonishing, freeing up time for crews to move to other construction activities to help meet the demanding timeline.
Figure 1. Victaulic fabrication solutions and HDPE couplings installed with ease and enhanced job site safety by eliminating the need for fitting-to-fitting and vertical fusing.
Along with the ease of installation and onsite time savings, Victaulic systems also enabled simple field correction of alignment errors, which minimised construction schedule disruptions on the Gondor project. Initially, unbeknownst to Crestwood or Victaulic, the tank fabricator had produced nozzle connections of variable lengths, which did not match with the tank submittals. Victaulic mechanical joints allowed for quick field correction and fit up, keeping the project on schedule amidst unforeseen circumstances.
Figure 2. Victaulic solutions minimised schedule disruptions and improved construction quality by enabling simple field correction of onsite alignment errors.
According to Donnelly: “With the local Victaulic team doing training for our contractor, they were able to make those modifications easily.”
Mechanical solutions deliver long-term efficiencies
The use of prefabricated HDPE pipe, in conjunction with Victaulic joining solutions, enables owners to achieve multiple “wins,” uncovering opportunities for cost savings and risk reduction while at the same time improving construction quality.
Since the project’s completion, Donnelly said there have been no significant maintenance issues at the Gondor facility. “Crestwood will continue to consider Victaulic for low-pressure tank farm applications,” said Donnelly. “The efficiencies of the Victaulic approach are hard to beat.”
Author: Greg Bannec, Sales – Oil, Gas & Chemical, Victaulic
Read the article online at: https://www.oilfieldtechnology.com/special-reports/28012021/making-ends-meet/