Robotically Applied Polyurea Significantly Improves Quality Of Traditional Field Applied Geotextile Liners
Unlike field spraying, application of polyurea in a controlled environment using automated robots assures a consistent mil thickness to meet job specs, improves performance quality, and rapidly increases speed of installation.
For coating contractors, the use of geotextile liners sprayed with polyurea has shown tremendous promise for applications on bare ground or a substrate that is expected to shift, move, or crack. Together, this combination of liner-plus-coating delivers a seamless, extremely durable, monolithic surface that retains some flexibility to stretch and move without being compromised.
The challenge, however, is that the application of these polyurea spray coatings can be inconsistent when applied in the field, leading to variability in the mil thickness and performance quality of the coating. In fact, a variety of factors—including wind, rain, humidity, temperature, operator fatigue, human error, and natural variability—has lead to a desire to have the coating pre-ap
plied by automated robots in a more controlled environment, indoors.
Through precise metering as well as control of the indoor manufacturing environment, robots can apply thicker, more consistent mils of coatings across the entire surface.
This dramatically improves the quality and reliability of the liner, compared to those sprayed by hand in the field. The pre-sprayed liners are delivered complete with texture and can be rolled out and seamed together to complete the job in a fraction of the time. The robot can spray to virtually any mil thickness required and custom liner sizes can also be factory ordered to meet the needs of any project. The same material that is used to manufacture the liner is also used to spray the seams together. The specially formulated polyurea sets up and cures almost immediately and the project can be returned to service in a fraction of the time as before.
Markets for Liners
Pre-sprayed liners are increasingly being utilized in a variety of markets, including secondary containment and vapor barriers. Typically, secondary containment involves coating a protective barrier or coating to contain any potential leaks from above ground petrochemical storage tanks. Secondary containment liners are used for railway loading and offloading stations, jet fuel storage tanks, reservoirs, and water impoundments as well.
The liners are also widely used for above and below grade waterproofing, wet wells, lift station manholes, and water/wastewater treatment.
Another emerging use of the liners is as a vapor intrusion barrier for brownfield sites such as former manufacturing sites that require remediation before new construction. In this application, a pre-sprayed liner is installed on the graded surface prior to pouring the foundation to prevent any vapors from intruding into the occupied space.
“With field spraying, you are basically manufacturing the liner outdoors,” says Louis Butkovich, President of Triton Polyurea, a Michigan based applicator.
The trouble with this, according to Butkovich, is that no applicator can spray as consistently as a robot.
“When applicators spray outdoors, we may stop for many reasons: wind, rain, lunch break, or we’re out of product,” he says. “When we return to the project, we may wonder where exactly did we leave off and at how many mils of thickness?” This can lead to over-sprayed areas where polyurea is unnecessarily wasted and thinner areas that provide less protection.
Butkovich says that another challenge of spraying outdoors arises when the liner’s coating has not yet fully cured but is in contact with harsh chemicals. When this occurs, the polyurea will not perform as expected and could require re-spraying.
“In one job we did, gasoline had spilled into the containment area and was basically embedded in the asphalt,” says Butkovich. “When we put down the geotextile and sprayed polyurea over it in the field, it was under immediate chemical attack.”
While Butkovich had previously sprayed liners in the field, he has since turned to pre-sprayed, robotically applied liners by MatLor, LLC, the original developer and manufacturer of the patented RoboLiner® system.
Unlike typical field application, the system enables the manufacture of polyurea coated liners in a controlled environment out of the wind and elements, so the liners arrive at the job site fully cured and ready for rapid installation.
Butkovich adds that since the pre-sprayed sheets come fully cured, it is immediately resistant to any residual harsh chemicals.
He was also impressed by the speed at which the liners can be installed onsite.
“When the liner is sprayed in the factory and is transported to the jobsite, the work is 95 percent completed,” he says. “In the case of a vapor barrier, all you have to do is seam the pieces together, terminate the liner to the building’s footprint, and spray any pipe or other penetrations.”
Today’s advanced robotic design allows consistent liner spraying to very precise specifications, which improves the quality of the end product.
“A robot can be designed and programmed to produce a perfectly consistent polyurea sprayed liner every time,” says Mike Whitener, President of MatLor, LLC, who patented the process and previously operated his own polyurea applicator business for over a decade.
“No applicator spraying by hand can match the consistency of an automated robot, and unlike human beings they never get tired,” he says.
Pre-sprayed geotextile liners created with the RoboLiner System can also provide a competitive edge for contractors because they can bid jobs based on higher quality and expedited job completion, rather than just on price, adds Whitener.
Because the RoboLiner System process is patented, contractors must purchase the product from MatLor, LLC or a licensed manufacturer.
According to Whitener, MatLor, LLC has successfully defended and settled several attempts to infringe on his patents, which specifically apply to robotically sprayed liners in controlled environments – not in the field. MatLor, LLC currently holds US Patent 8,500,941 B2, US 9,056,714 B2, and Canada Patent CA 2683244.
However, companies that want to offer the RoboLiner spray-applied liners can do so through a licensing agreement with MatLor, LLC that includes the automated robots along with training and support. This is the route Ameraguard, a manufacturer of protective coatings for a variety of industrial applications, chose.
According to Kaveh Meghdadpour, Vice President of Ameraguard, the company understood the growth potential of the pre-sprayed liner market and after due diligence and review of the existing patents decided to become a licensed manufacturer.
“Our legal counsel reviewed all of RoboLiner’s patents and found them valid and enforceable, so we decided to become a licensed manufacturer,” says Mr. Meghdadpour.
Now, three year later, Ameraguard continues to manufacture and distribute the pre-sprayed liners, with a focus on the oilfield and construction industries. The company has a facility dedicated to the RoboLiner system.
“With the system we can precisely and consistently apply polyurea on virtually any liner or substrate: on woven, non-woven, and a variety of weights, including those used for vapor barrier products,” adds Mr. Meghdadpour. “The robotic application is going very well and opening new markets for us.” •
For more info on pricing or licensing, call 239-410-1522 or visit www.Roboliners.com.
Photos courtesy of Total Containment Solutions, Inc.