The Challenge:
On a pipeline installation near Godley, TX, pipeline contractor Pumpco Inc, (Giddings, TX) was contracted to install numerous 12-inch steel pipeline laterals.  The job took place in the Barnett Shale Formation, southwest of Ft. Worth, which is one of the most active drilling locations in central Texas.

On the last remaining bore Pumpco was faced with several challenges, a 640 foot bore that included 35’ of elevation changes, crossing a Santa Fe railroad track and Texas Highway 171.  The challenge was further compounded by ever changing sub surface conditions, which alternated between unconsolidated soil and rock to solid shale and limestone formations.

A similar crossing had been completed with a mud motor less than ½ mile north of the Godley bore. The crew encountered extensive fluid loss and surface frac-outs in the unconsolidated and layered formations encountered. The frac-outs caused the inspectors considerable concern due to the threat posed to the sub-base integrity under the highway and railroad right-of-way.

The Equipment:
Pumpco kept three Vermeer D100×120SII horizontal directional drills busy for months crossing roads and creeks along the 31 mile right-of-way in Johnson County.  Due to the fluid loss and frac-outs encountered in previous bores, Pumpco was compelled to consider an alternative pilot drilling method for the Godley bore.  The Steerable Air Hammer System from StraightLine was selected.

Ron Becker, StraightLine’s lead air hammer field technician, was contacted to consult on the job. With over 30 successful air hammer bores in layered rock formations in many of the most demanding conditions in the country, Becker was confident the bore could successfully meet the rigorous Texas Department of Transportation (DOT) and the Santa Fe Railroad requirements.

For this bore, a StraightLine AH5.0 Air Hammer System was paired with an Ingersol Rand 1100-CFM/350-PSI air compressor.  Becker, knowing the bore would contain both unconsolidated and solid formations selected this compressor for its output volume which helped keep the hole clean throughout the duration of the bore.

The Bore:
The Pumpco crew set up their Vermeer D100×120SII directional drill approximately 430 feet east of the rail road tracks, at an elevation 35 feet higher than the final exit pit, located just over 200 feet west of Highway 177. The sloping terrain along the bore path also included a ditch on both sides of the railroad track and a steep bank on the west side of the highway nearest the exit pit.

The extremely tight bore profile was drawn up by Universal Insco, the design engineering firm on the job.  As the bore progressed, measurements were taken at regular intervals with a DigiTrak Eclipse walk-over drill head monitoring system. In most cases, measurements and marks were made at each 20-foot drill pipe change-out. At critical points along the bore, measurements were taken every 5 to 10 feet. Throughout the course of the bore the air hammer’s steerability was precise, keeping the bore path within less than 6-inches of the bore plan over the entire length of the bore.

Throughout the 640 foot bore the air hammer maintained a near perfect left to right and top to bottom running line. It was also important to maintain the bore plan profile so that the bore hole produced would easily accept the installation of the 12” steel pipe that would be installed. The pilot bore and backream was completed on the third day and the 640 foot section of pipe was easily installed into the hole in a few hours the following morning.

The Observations:
Progress was measured each day by the number of drill rods added to the drill string. On average, a 20-foot rod was added every 30 minutes depending on rock hardness.  Interestingly, it was observed that softer formations took longer to penetrate, this performance was obvious to the Fort Worth based, Texas DOT inspectors:

“When the bore crew hit rock, it didn’t stop the air hammer. It’s obviously designed for hard conditions. The harder the better.”

State DOT and railroad inspectors carefully observed the pilot bore over its 16-hour duration. Officials were keenly interested in how the StraightLine Air Hammer minimized environmental risks. The inspectors’ questions were answered during the first day, as the “spoils pit” where the bit entered the side of the rocky layer began to capture the spoils created by the hammer.  Critical to the success of any air hammer bore in rock is getting the cuttings out of the bore hole as the bore progresses. As each 20’ section of drill pipe followed the hammer into the ground there was an observable spray of rock fragments carried out of the hole via air and a water/polymer combination. One of the senior inspectors observed:

“You knew exactly what was happening during the bore by the chips being blown out of the bore hole.”

Based on the first day’s performance, the StraightLine AH 5.0 Air Hammer System proved its ability to pound through difficult rock and accurately navigate extreme elevation changes all with a fluid consumption of just over 1-gpm per foot. Both the performance of the Hammer System and the extremely low consumption of drilling fluids exceeded the expectations of the DOT and the railroad inspectors. The concern of subsurface damage was put to rest. When asked to comment on the nominal amount of fluids required, a Texas DOT inspector summed it up this way:

“On a traditional horizontal crossing, using lots of drilling fluid, you don’t always know what’s happening until you are done.  Problems with this method often show up weeks or even months later, when the surface structure caves in because of the void created by excessive amounts of drilling fluid.

The Outcome:
The 640-foot pilot bore was successfully completed in 16-hours. Impressively, only 800 total gallons of fluid were used to complete the pilot bore.   The nominal use of water demonstrated the air hammer’s unique ability to produce and maintain a pilot hole while consuming very little fluid thereby eliminating the risks of sub-base damage.

As the HDD industry has grown, so has our line of swivels. Our newest introduction to the family is an impressive 60-ton swivel available in either BOX X CLEVIS or CLEVIS X CLEVIS configurations. This Heavy-Duty swivel weighs in at 365-pounds, measures 10” in diameter and is 29” long.

In the process of developing industry specific swivels, StraightLine engineers led the way in the development of bearing and sealing systems that have proved to thrive in harsh underground environments. Over the years it has become evident that our original designs have stood the test of time and continue to deliver rugged reliability. So how do you deliver rugged reliability? 1) start with “angular contact” bearings, which are designed to handle both thrust AND radial loads, 2) the appropriate size and quantity of “angular contact” bearings are then assembled in a stack that provides safe performance at the rated load, 3) within the bearing stack each swivel must have two bearings that are positioned in the thrust (pushback) direction in the event that the product needs to be pushed backwards and finally 4) the sealing system must consist of 1 shaft seal and 2 lip seals with steel reinforcing rings to prevent soil and drilling fluid intrusion.

Our exceptionally crafted swivels are off the shelf available in 5-ton, 15-ton, 20-ton, 30-ton, 45-ton & 60-ton sizes. Quality, rugged-reliability and our commitment to continue to exceed industry standards – that says it all about StraightLine’s complete line of swivels.

Location: S. of Asheboro, NC

Equipment: Vermeer 24×40SII – Sullair 1150/350 compressor – StraightLine 4” Air Hammer System.

Drilling fluid type & flow rate: water @ just over 1-gpm.

Ground conditions: 10 foot minus blue granite boulders under the freeway in a sandy clay base material.

Project: placing 6” HDPE pipe to act as a conduit for power. Total bore length was 450’. The depth requirement under the highway was 16’ minimum and 5’ minimum under the exit side ditch.

Bore path: there was 10’ of elevation change from the entrance to the ditch on the opposite side of the highway. The hammer entered the ground at minus 18% slope held this pitch until the hammer reached the edge of the highway. At that point the operator began to steer upward until a minus 5% slope was achieved. A depth of 17 ½’ was maintained under the highway and 7’ 6” under the ditch. Once the required cover had been obtained the hammer was rotated to the 12 0’-clock position and brought out of the ground.

We’re continually working on our website so that it will serve you quickly, efficiently, and completely. This is just one of many improvements we’ve made, and we have even more in the works.  We’d love to know what you think!  Please feel free to contact us with any additional questions or feedback you may have.

The ability to combine these three elements makes Gregg a tremendous asset to his customers with whom he’s earned a solid reputation as “the guy who will do whatever it takes to get the job done.” This new position will provide hand delivered products when and where they are needed. Gregg will be based out of Florence, SC and will serve the Carolinas and portions of Georgia and Florida.

Detailed Product Pages

Our new product pages are rich and informative. Where merited, each product has a detailed description of the product and/or its uses, and a gallery of images used to spotlight that product’s features, benefits, and – in some cases – even technical specifications.

Features Up Close

When you click on any of the gallery images, a larger view of that image is presented to you, which in many cases tells you something specific about a feature and benefit of the product you’re looking at.  Many pages have multiple images and different views of each product so you can get a good feel for the excellence of each of our products.

We’ve re-vamped our site’s navigation to make it as easy as possible to get around.  A familiar drop-down menu system has been implemented to make it easy to get almost anywhere in our site in just a single click.

Custom Reamer Quote

We’ve also made it very easy to get in touch or get a custom reamer quote. You can tell us what kind of reamer you want any time of day or night.  All you have to do is choose the style, diameter, and threaded connections you want on your reamer.  We’ll then contact you with the specifics and costs associated with your new reamer – it’s that simple.

Finally, we’ve introduced the “Fear No Ground” blog, where we post news related to StraightLine (like this announcement) or news concerning the horizontal directional drilling industry in general.

We’re really excited about this new website and the opportunity to make finding information easier and more intuitive for all our customers.  But we’re not stopping here.  In the coming months keep looking for more new features and continual improvements to this new site!