San Antonio Water System Uses HDD for Expansion Project By Steve Cooper How do you fuse together, bore and pull a 36inch diameter, thickwalled highdensity polyethylene (HDPE) pipe string that links 45foot sections into even longer threads? The answer is simple. Basically, the same way you do for any HDPE pipe system – face it, fuse it, bore it. That is how crews dealt with installing a new water main system in northwest San Antonio where one string of HDPE pipe alone ended up being 1,000 feet long. The project required a 20foot entrance drop and exit rise so that pipe could be pulled under a creek. The water transmission main project here will connect the existing water mains with a recently constructed pump station and to accommodate future demands in the area. San Antonio Water System selected the contractor and method in a bid process based on best price. "This new water main will connect the gap between the new pump station and the existing main to provide additional capacity for future growth in our city," explained Juan G. Rodriguez, P. E., project engineer, production and transmission engineering department for San Antonio Water System (SAWS). "It goes through a very rough area that has a lot of rock and ravines not the easiest terrain to bore through plus we had to deal with an active creek. The HDPE pipe is tough and provides the type of deflection you need for directional drilling and has the best cost effectiveness." "This was a very challenging installation, but perfect for HDPE pipe," observed Tony Radoszewski, executive director of the Plastics Pipe Institute, Inc. (PPI), a nonprofit, manufacturingbased trade association dedicated to expanding awareness about economics, performance benefits and environmental advantages of plastic pipe systems. "And it's not a typical Horizontal Directional Drilling (HDD) HDPE pipe project because SAWS elected to use very thickwalled
Transcript
San Antonio Water System Uses HDD for ExpansionProjectBy Steve Cooper
How do you fuse together, bore and pull a 36inch diameter, thickwalled highdensity polyethylene (HDPE) pipestring that links 45foot sections into even longer threads? The answer is simple. Basically, the same way you do forany HDPE pipe system – face it, fuse it, bore it. That is how crews dealt with installing a new water main system innorthwest San Antonio where one string of HDPE pipe alone ended up being 1,000 feet long. The project required a20foot entrance drop and exit rise so that pipe could be pulled under a creek. The water transmission main projecthere will connect the existing water mains with a recently constructed pump station and to accommodate futuredemands in the area. San Antonio Water System selected the contractor and method in a bid process based on bestprice.
"This new water main will connect the gap between the new pump station and the existing main to provide additionalcapacity for future growth in our city," explained Juan G. Rodriguez, P. E., project engineer, production andtransmission engineering department for San Antonio Water System (SAWS). "It goes through a very rough area thathas a lot of rock and ravines not the easiest terrain to bore through plus we had to deal with an active creek. TheHDPE pipe is tough and provides the type of deflection you need for directional drilling and has the best costeffectiveness."
"This was a very challenging installation, but perfect for HDPE pipe," observed Tony Radoszewski, executive directorof the Plastics Pipe Institute, Inc. (PPI), a nonprofit, manufacturingbased trade association dedicated to expandingawareness about economics, performance benefits and environmental advantages of plastic pipe systems. "And it'snot a typical Horizontal Directional Drilling (HDD) HDPE pipe project because SAWS elected to use very thickwalled
pipe greater than four inches in thickness in a larger diameter size to meet its design specifications. But, even at thisextreme, the HDPE pipe installs easily and delivers a highly sustainable, completely leakfree system with fused joints.And these characteristics are the norm when using HDPE pipe."
Pressure class for the system is 200 psi, which provides enough power for the distance between pumping stations, thearea's elevation and the number of projected customers. "This pressure zone is located on those higher elevationareas in San Antonio's hill country so the water has to travel up as well as far," Rodriguez said.
The project required more than 1,900 linear feet of HDPE pipe. Manufactured by Performance Pipe, a division ofChevron Phillips Chemical Company, LLC, in Plano, Texas and a PPI member company, the pipe is DriscoPlex®4000/4100 36inch DIPS DR9 PE 3408 with a 4.62 inch wall thickness.
The project included three HDD pulls. "They were labeled Line A, B and D," said Bob Gajeske, Jr, whose Texasbasedcompany, Gajeske, Inc., supplied the pipe, the McElroy fusion equipment and also performed the fusions. "Line B isthe longest pull....it was almost 1,000 feet long alone; but we didn't experience any problems fusing the pipe. We justhad one operator on the fusion machine, a McElroy (MegaMc®) 1600, with a fourjaw clamp and hydraulic lift. That 65inch unit had absolutely no trouble clamping, facing or fusing that pipe at all – it worked just as easily as when we fuseHDPE pipe in smaller diameters with thinner walls.”
McElroy, a member of the PPI, provided the pipe stands to hold and align the pipe which had selfcontained gasolineengines that power the lift. A trackhoe was used to load the pipe sections into the fusing machine and onto the pipestands and to pull the pipe.
"These hydraulic pipe stands really helped with the process," Gajeske continued. "They enabled us to quickly andeasily maneuver the pipe back and forth, up and down, in order to get a good alignment in the fusion machine. Thatreally sped job progress. Initially it was projected that the pipe was going to take about 27 days for us to fuse all of it.We ended up doing it in 14 days. Not much was different from fusing smaller, thinner wall HDPE pipe. We just had tocrank the pressures up. Things went really quickly and smoothly.
Imperative to the success of the project was the ability to utilize theHDD installation method for specific areas. "It was essential that wedirectionally drilled to circumvent that creek," said Rodriguez. "Wesaw it as the only option. We couldn't dig a trench due to the steepterrain and you can't have the water main exposed, especially onthese types of creeks in Texas which are known for flooding andwashout conditions. So we had to go under the surface, whichrequired going down more than 20 feet, then horizontally under thecreek. We did the same for the other areas that were just ravines."
The directional bore and pull was done by Cherokee DirectionalDrilling of Longview, Texas. "This job was not unlike any other job inmost ways," stated Kerry Holden, president and the onsite project manager. "But, because we needed to oversize thehole it was more like a tunnel when we got done – up to 48 inches. We first had to go in and shoot a pilot hole, thendo the rest in phases. After the pilot, we drilled 8 inch, 24 inch then the 48 inch. It took about three and half weeks to dothe largest one which was nearly 1,000 feet. Once we got the hole cut through, however, it took just a few hours to dothe pull."
The Cherokee crew used a selfcontained Vermeer Navigator® D330x500 Horizontal Directional Drilling System with330,000 pounds of pull back.
For the three lines that were pulled, Line A was 360 feet; Line B was 970 feet and went under the creek; and Line Dwas a 565 foot pull, down, under and up a 60foot deep ravine.
"HDPE pipe was the product of choice for the job because of its ability to perform under all the particularcircumstances we were dealing with here and because it could be directionally drilled." stated Rodriguez.
"Just the numbers alone on this job are staggering," summarized Radoszewski. "Thickwalled pipe fused for nearly2,000 feet in 14 days – then, add in the conditions, like being able to circumvent an active creek and defeat deepravines using horizontal directional drilling – these make this project remarkable and the team can be very proud oftheir successful accomplishments. Plus, using HDPE pipe in the most sensitive areas where failure simply isn’t anoption is a testament to the product. Despite all the difficult details, the crews felt this was just another HDPE job. Andthat I find to be the greatest attribute about this project, and directly tied to the merits of the pipe material: it’s justanother ordinary, dependable performance for HDPE pipe."
The Plastics Pipe Institute Inc. (PPI) is the major trade association representing all segments of the plastic pipeindustry and is dedicated to promoting plastics as the material of choice for pipe applications. PPI is the premiertechnical, engineering and industry knowledge resource publishing data for use in development and design of plasticpipe systems. Additionally, PPI collaborates with industry organizations that set standards for manufacturing practicesand installation methods.
Sincerely,
Tyler Henning
P.S. – Do you have an interesting job site that you would like to share? McElroy is always looking for fusion job siteswhere HDPE is being used and fused to solve an infrastructure problem. Contact Tyler Henning, public relationsspecialist at (918) 8319286 or by email at [email protected].
McElroy Socket Tooling Kits for Polyethylene PipeWith the new Socket Tooling Kits, you can locate and identify a specificrange of socket tooling equipment that fits your needs, instead of orderingeach piece separately. McElroy has selectively chosen the proper heateradapters, ratchet sheers, chamfer tools/depth gauges, and cold ring toolsfor a complete kit. All the equipment conveniently fits in a speciallydesigned tool box and tray to keep all of your socket tooling in one place.
All Socket Tooling Kits come with a MultiMc® Heater, Heater Sling, SpareChamfer Blade, and Operator’s Manual in a specialized Socket FusionStorage Box.
McElroy’s socket tooling is compact, lightweight, handoperated, andfeatures a microprocessorcontrolled heater.
Click here to learn more.
Understanding the TracStar® 28 and TracStar® 250
A new set of videos has been released from McElroy University Online, designed to help you understand why theMcElroy TracStar 28 and 250 are the premier options for fusing 2inch IPS through 8inch DIPS (or 63 to 250mm) pipe.
Our first video highlights the complete machine. The videos below feature a special video on some of the componentsthat make the TracStar 28 and 250 special:
Understanding the McElroy 28 and250 Fusion Carriages
Did You Know?McElroy’s social presence is continuing to grow. You can join McElroy on Facebook, Twitter, YouTube and LinkedIn.The social networks present great opportunities to get even more news on products and industry happenings directlyfrom McElroy.
These photos come from Gordon Thomson via McElroy’s Facebook fan page. If you ever have a picture of a McElroymachine out on the job, feel free to post it on our page! Thanks to Gordon for posting these pictures from various sitesin Scotland!
If you have photos from a jobsite, we'd love to see them! Yours may be chosen for the next issue of McElroyConnections. Simply email your photos to Tyler Henning, at [email protected].
A Chicago Tribune Editorial recommends gas pipes be replaced with...you guessed it: #HDPE.http://ow.ly/lSkS4 Jun 10thMcElroy University Online has a new video that will help you learn the benefits of the TracStar® 28 and 250.http://ow.ly/lKsLs Jun 5thHave you ever used a DataLogger®? #hdpe #fusion #buttfusion http://ow.ly/lK9r9 Jun 5thCongratulations to Jim Craig, a recipient of the PPI's Honorary Lifetime Achievement Award!http://ow.ly/i/2h6PD Jun 4thThe interactive interface of McElroy’s Online Parts Finder feature allows you to also identify these parts on atablet or smart phone.Jun 4thA DynaMc 250 EP is a great match for #PPR piping. Watch this video from McElroy University for more.http://ow.ly/lkgez May 23rdOur thoughts are with all those that have been affected by the tornadoes here in our home state of Oklahoma,and across the Midwest.May 21st@PHCnews named the Spider 125 as the Tool of the Month. Check out their May issue and turn to pg. 74 formore! #PPR #socketfusionMay 20th
Alliance for PE Pipe WaterWorld Water Tech Online North American Society of Trenchless Technology Plastics Pipe Institute
