Case Studies

Project Type
OIL & GAS FACILITY
Location
FORT SASKATCHEWAN, ALBERTA, CANADA
Length / Hole Diameter
7,000 m (4.3 miles) / 610 mm (24 in) waterline
Divisions
The Hydrovac Company

FORT SASKATCHEWAN PLANT

LINE DISCOVERY & MAPPING

Project Summary

This plant has been successfully operating in Fort Saskatchewan since the 1970s. Only within the last decade have detailed as-built drawings been an industry requirement. These generational facilities provide substantial challenges when installing new pipelines.

The project involved the installation of 7 km (4.3 miles) of 610 mm (24 in) new water line. The Hydrovac Company was selected to daylight all underground utilities and hotlines.

Key Challenges

The Hydrovac Company began by digging an exploratory trench around the entire plant perimeter. We were anticipated finding 35 lines. Instead, we identified hundreds!

This unexpected discovery meant a new action plan would need to be formulated to ensure drilling could proceed in a safe manner. The data provided by The Hydrovac Company helped PME make an informed decision.

A new strategy was in place. The Hydrovac Company chased a crisscrossing network of lines across the property to determine where they were going. We provided detailed documentation of all line locations and depths (including photos) as part of our due diligence.

Our crews supported the HDD component of the project by confirming the depth of rods and reamers and provide site holes for visual verification of the bore path. In addition, our hydrovac trucks were used to manage the transportation of all fluid associated with the boring project.

Services Provided

Hydrovac

TUNNEL BORING / PIPE JACKING

Tunnel Boring and Pipe Jacking Systems are used to hydraulically install underground pipelines up to 4.2 m (168 in) in OD range within strict alignment and grade tolerances. The likelihood of settling or sloughing is very low. Wheel machines are equipped with various cutter heads and sand shelves. A closed-face attachment is available for boring in unstable ground conditions. This versatile system can be easily adapted to work with any jacking pipe, in any pipe joint length. It can accommodate a wide range of pipe diameters.

Tunnel Boring Machines are used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They can bore through hard rock, sand, and almost anything in between. Tunnel diameters can range from 1 m and exceed 15 m (3 ft to 49 ft).

The Crossing Group - The Tunneling Company - Tunnel Boring - Pipe Jacking - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

SLIP BORING

A boring technique commonly used for installing oil & gas pipelines ranging from 51 mm to 1067 mm (2 in to 42 in) in diameter without leaving casing in the ground. Product pipe is welded to steel casings and either pushed or pulled through the ground in sections. The casing is cut off and removed, leaving just the product pipe. Maximum installation length is 150 m (492 ft).

The Crossing Group - The Tunneling Company - Slip Boring - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

DOWN THE HOLE HAMMER

A pneumatic hammer is attached to the inside edge of the casing. The front of the DTH breaks cobles, boulders and even solid rock into small pebbles or dust. The spoil makes its way through the hammer and into the casing, where it is removed by airway augers.

The Crossing Group - The Tunneling Company - Down The Hole Hammer - DTH - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

GUIDED BORING

A Guided Boring Machine (GBM) is used to install 305 mm to 3.6 m diameter pipe (12 in to 144 in) with grade and alignment precision. It is commonly used for installations 50 m to 150 m in length (164 ft to 492 ft) or when line and grade accuracy is critical in displaceable soil. Our GBM is extremely versatile and our customers continually approach us with new applications.

The pipe installation involves a two-step process where launch and reception shafts are strategically located to minimize surface disruption. A pilot tube with a theodolite guidance system is then pushed through the ground at the precise grade and alignment specified in the design into the reception shaft. A reaming head is welded to the pilot tube and the casing and the pilot tube is used as a guide to install casing. The GBM can be used in conjunction with auger boring or pipe ramming methodologies.

The Crossing Group - The Tunneling Company - Guided Boring - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

PNEUMATIC PIPE RAMMING

Pipe Ramming is used in a wide variety of soil types including gravel, cobble or sand. A pneumatic hammer is attached to the back of the casing pipe and driven through the material at any angle: from horizontal to vertical. The material is cleaned out of the pipe using an auger boring machine. Pipe Ramming methods are used for pipe diameters of 305 mm to 3.6 m (12 in to 144 in).

The Crossing Group - The Tunneling Company - Pneumatic Pipe Ramming - Tunneling - Augering, Boring & Pipe Ramming