While fiber optic cables to the home are designed to provide access to the latest that technology has to offer, like high speed broadband internet and hundreds of high quality, high definition television programs, the tools that are often used to install those cables are often very basic. One in particular, the pneumatic piercing tool, has been performing just these types of service installations for over 40 years. While the accuracy of the tool has improved since the early days, the concept behind it has not and today’s crews are improving their efficiency, lowering the restoration costs and generating good public relations through the use of this piece of classic trenchless technology.
Verizon is one of the major telecommunication companies pushing fiber-to-the-premises (FTTP) services. The company began implementing its FTTP program in early 2002. Since then the program continues to expand and now includes projects in several states and large cities like Tampa, FL. In May of this year, Verizon announced that an initial group of more than 40,000 Tampa area households were now able to receive its product offerings through its all-digital fiber optic network. The company had already deployed over 3 million feet of fiber in the Tampa area. By the time the program is scheduled to be complete, five years from now, over 9 million feet of fiber optic cable will be installed.
Installing the conduit that houses the cable is part of Stuart Greenberg’s job. As owner of Arrow Construction, Dunedin, FL, his crews are installing conduit in various locations in Florida, helping Verizon complete its FTTP program. The piercing tool plays a major role in daily operations. Greenberg has been using piercing tools for over 15 years. Over the last five years his crews have been using them on a regular basis. For the Verizon project, they are using them daily. He said, “On a good day we’re trying to install 1,000 feet of conduit. If I could use the piercing tool all the time, I would. With a directional drill if we get ten (10) 40-foot shots that’s a good day. With piercing tools we can do over twice as much work. We can do 20 in a day with the missiles.”
Piercing tool specialist Jason Land from trenchless equipment manufacturer TT Technologies, Aurora, Ill, supplies Grundomat piercing tools and other pieces of trenchless equipment to Arrow Construction. According to Land in addition to piercing tool productivity, minimal disruption is a key benefit of the trenchless piercing tool. He said, “Restoration is a time consuming and expensive process. It can make up almost 80% of the cost of an installation project. With the cost of restoration so high, trenchless options are extremely attractive, piercing tools especially. Plus the trenchless application is ideal for these last mile operations. Everyday Arrow Construction crews are working in established neighborhoods with driveways, sidewalks and landscaping. Not only are they saving money and time, they’re building goodwill with the residents.”
Arrow Construction partners Steve Vance, Miguel Esquivel and Stuart Greenberg have over 18 years combined experience working with telephone, CATV, fiber optics and power. Arrow Construction crews have been working on the Verizon FTTP program for two years already. According to Greenberg the project has kept them busy. He said, “We’ve been putting in 8 to 10 hours days and half day Saturdays as well. Our regular activities include stitch boring primarily in front yards and going under driveways. We’ve gotten so many compliments on our work on this project and we let our work speak for itself. Now we’ve been flooded with calls for other projects. It’s almost at the point where we’re having to turn down work!”
Typically piercing tools range in size from as small as 1.75 inches in diameter up to 7 inches and can bore accurately up 150 feet in length. A minimal crew compliment is needed to operate a piercing tool and only small entry and exits pits are required for most projects. The tools can usually be fitted with different types of cones or heads for various soil conditions. In addition, piercing tools can be used to perform a standard bore or they can be outfitted with a range of pipe and cable pulling adapters/accessories to pull in product pipe, conduit or cable while boring.
Land said, “The Grundomat is very versatile. It can be used for other applications like pipe bursting and pipe ramming. Because the piercing tool can be used in so many ways, it represents one of the most useful trenchless construction tools available. Contractors and utilities can get a lot out of their piercing tools. For Arrow Construction the tools get put to the test everyday.”
Accuracy, which was once an issue with the piercing tools of 40 years ago, is not an issue with today’s reciprocating chisel head, spring-loaded piercing tools, like theGrundomat. Greenberg said, “The guys keep it simple. They line it up, use a level, and then shoot it. We recently bored under a parking lot, two bores at 80 feet and two at 88 feet. The pit was about two-shovel-lengths wide. And we hit it like a directional bore. People associated with the project were telling us, ‘You can’t shoot over 40 feet with those missiles.’ I said, ‘Well, we completed two of them before you even got here!’ We’ve proved them wrong time and time again.”
According to Land, the Verizon project is giving the Arrow Construction crews the opportunity to use the piercing tools to the fullest. He said, “Arrow has two 12-man crews boring under driveways and yards everyday. Basically crews are installing single, double and triple conduit runs of inch and a quarter polyethylene. They probably have over a dozen piercing tools and they’re working them constantly.”
Arrow crews are installing conduit for bores and path. Greenberg explained, “For the path, which is the main line that feeds the neighborhood, we’re performing what’s called stitch boring with the piercing tool. We dig small pits on either side of the driveway. We missile from one side to the other, then missile the yard to the next driveway pit. The shots are usually 30 to 40 feet long. With small pits, you’ve eliminated a large portion of restoration.
For a majority of the path work, Arrow crews use 2-inch through 3.75-inch diameter pneumatic piercing tools. Typically the piercing tool pulls in mule tape. Once the run is complete, crews pull the conduit in with the mule tape. In certain circumstances they will complete the bore, then attach the conduit to the front of the tool and back the tool through the boring, pulling in the conduit. Depending on soil conditions boring times range from a few minutes to a half an hour. For the bores, under streets we use a Grundodrill 4x directional drill also manufactured by TT Technologies.”
The Arrow crews, however, are not installing the fiber themselves. They are simply installing the conduit that protects the fiber. Greenberg said the installation of the fiber usually occurs within a week, after the conduit has been completed and inspected. By that time, Arrow Construction crews have moved on to begin boring in the next neighborhood.
Trenchless Technology, July 2006