About Pilot Tube Guided Auger Boring Systems:
By using the pilot tube trenchless method of installing underground utilities, water lines and sanitary sewers, you can reduce costs by 50% when compared to complicated laser controlled microtunneling systems.
What Is Pilot Tube Guided Auger Boring?
Pilot tube guided auger boring was developed in Germany by Dr. Peter Uffman of Bohrtec for the installation of trenchless house connection sewer pipes. The technology was later developed further to install mainline sanitary sewer pipes on line and grade over 300’ from manhole to manhole as an alternative to expensive tunnel boring machines. ICON Tunnel Systems is the exclusive distributor for Bohrtec pilot tube guided auger boring equipment in the United States and Canada.
How Does It Work?
Pilot tube guided auger boring or pilot tube microtunneling or guided auger boring equipment is used to install pipe that has an outside diameters from 4” to 55”. Pilot tube guided auger boring is a trenchless method of installation for small diameter pipes with a grade and alignment accuracy that the gravity sewer and water industry demands. The pipe is installed in two ways, either a three-phase installation or a two-phase installation, starting with a launch and reception pit at either end of the proposed drive length.
When faced with a gravity sewer project that requires a precision installation with line and grade accuracy of 1” or better, the pilot tube guided auger boring system will provide the consistent accuracy required.
Where Does It Get Its Power?
The Bohrtec-designed hydraulic power packs provide constant power for the auger boring machine. These power packs provide a minimum of 50 kilowatts or 67 horsepower with a diesel engine and variable speed with a silencer built in. Each system will provide hydraulic flow of 0 to 34.8 gpm and up to 5,000 psi working pressure.
The Bohrtec-designed hydraulic power pack is set away from the main boring unit and hydraulic hoses are run between the power pack and the main boring unit. The power pack is operated from the main boring unit in the launch shaft using a remote control. This allows the operator to control the power pack and engine functions safely and easily from inside the launch pit.
Individual levers or sticks control the forward jacking, reverse pullback and rotational movement of the system. For ease or monitoring and recording the machines operation through out the installation, hydraulic gauges are mounted in the operator’s line of sight just above the individual levers or sticks.
Digital Theodolite Camera
This system has already been proven and is the same digital theodolite camera system that our already popular Pilot Tube Systems has been using in the field for over 25 years. The use of this camera system allows the contractor to constantly monitor the illuminated LED Target and Front Steer Boring Unit (FSBU) in order to make steering corrections as the FSBU advances through the ground for Line and Grade.
What Makes Our Pilot Operation Better?
The pilot tube operation itself is what makes the accuracy of the pilot tube guided auger boring system possible. Bohrtec’s pilot tube rod construction is like no other in the world; they have perfected this design over the last two decades. Bohrtec is the only company operating in the United States that uses independent inside and outside pilot tube rods in their double wall pilot tube design. This means the inside rod turns and rotates the head only, not unlike a directional drill design. The outside pilot tube rod is essentially a steel jacking pipe with male and female threaded ends. It jacks in place, never turning during the steering operation of the pilot tubes.
By not having to rotate the inside and outside pilot rods simultaneously through the ground allows Bohrtec to use less torque in this operation. As a result we do not have to introduce messy lubricants, gels or bentonite to reduce friction. This also reduces additional heat caused by rotating the outer skin, which can slow the operation and decrease production.
THREE-STEP INSTALLATION DIAGRAM
Step one: Install hollow pilot rods establishing 1” line and grade.
Step two: Install casings and augers behind the hollow pilot rods. Remove the pilot rods as they are pushed out in the end pit or reception area.
Step three: Install the desired jacking pipes behind the casings and augers as seen in Step 2. Remove the casings and augers as they are pushed out in the end pit or reception area.
Step four: If the desired jacking pipe is larger than the casings and augers used in Step 2, then an increase kit with hydraulic reamer can be installed to handle the larger jacking pipe.
THREE DIFFERENT APPLICATIONS
WITH ONE SYSTEM
Pilot Tube: Application 1 (New Installation of Jacking Pipes for Gravity Sewers)
The first application is the trenchless installation of jacking pipes for gravity sewer projects. Owners, Engineers and Construction Managers demand these sewers be installed within extremely tight tolerances, leaving little room for error. With the pilot tube guided auger boring systems from ICON Tunnel Systems you can now meet these demands and install jacking pipes within a 1” line and grade for gravity sewer projects. Three-step installation required.
Pilot Tube: Application 2 (Exact 1” Line and Grade with simple adaption to Auger Boring Machines)
The second application is for the trenchless installation of steel casing pipes for the auger boring industry. Thousands of contractors own diesel auger boring machines that run on steel tracks but lack the superior line and grade guidance of the pilot tube systems. ICON Tunnel Systems can easily adapt the BM400LS pilot tube machine to all boring machine models for establishing a 1” line and grade up to 500’ in length depending on your soil conditions. Two-step installation required.
Pilot Tube: Application 3 (Establishing 1” Line and Grade with the PT Pullback Expander for large diameter plastic or ductile iron pipes)
The third application is for the trenchless installation of plastic or ductile iron pipes for gravity sewer projects. The PT (Pilot Tube) Pullback Expander effectively provides a 100% field proven alternative to Horizontal Directional Drilling that contractors can use to install these types of pipes for gravity sewers that will meet the required 1” line and grade that the water and sewer industry demands. The PT (Pilot Tube) Pullback Expander is an accessory item for our pilot tube systems. Three-step installation required. *Picture not shown, please visit www.icontunnelsystems.com for more information.
Digital Theodolite Camera
This device is the center of the Bohrtec pilot tube system and enables the machines to steer through the ground while constantly maintaining line and grade precision. The plumb bobs shown above act as control axis points, which are dropped down from a string line overhead. This allows for the proper setup of both digital theodolite camera and the pilot tube machine to the exact line and grade for the job before the start of the proposed drive.
Jacking Force: 35,070.2 lbf
Torque: 2,950.24 lbf
Pullback: 20,907.23 lbf
Hydraulic Stroke: 2” x 16.93”
Weight of Unit: 1,322.7 lbs
Minimum Pit Size: 3.93’
Maximum Pipe O.D. 12” Round.
Can be used inside a 48” pipe to drill out.
INCREASE YOUR VALUE
BM400LS, BM400LSC (not shown), BM600L, BM600LSC and BM800LS can be used as a guided machine with pilot rods or as an unguided machine without pilot rods. The increased torque allows the contractor to use larger augers to install larger steel casings in various soils without steering, much like conventional auger boring machines. The dual functionality of these machines brings more value to the table.