Since Trenchless Advisors entry into the underground civil construction market it has proven through proper achievable designs, feasibilities and on site monitoring that many issues and potential problems that have occurred in the past are now significantly reduced or eliminated, saving the client money,
sliced-pic/28.jpg
sliced-pic/29.jpg
sliced-pic/30.jpg
TRENCHELSS TECHNOLOGY METHODS
Horizontal Directional Drilling
HDDs
Horizontal Directional Drilling is a construction method used to install a product/utility below the grounds surface on a horizontal plan with the added benefit of being steerable without disturbing the surface or above ground activities. Part of the Trenchless Technology group and methods, Horizontal Directional Drilling allows a conduit, pipeline, cable etc to be installed where other techniques such as open trenching would become dangerous, messy, time consuming and at times impossible to construct.
The Horizontal Directional Drilling procedure consists of three major objectives:
The Pilot Bore
Reaming Process
Product Installation
1. The Pilot Bore
Through the use of a drillhead, which penetrates into the ground formation, a bore hole is produced below the surface in line with the designated bore path. The drillhead location is monitored at all times by the use of a transmitter located in the drillhead sending information to a receiver on the surface. This information tells the operator the drillheads lateral position, depth, pitch & roll. The bore path may require the drillhead to be steered around existing services or below a structure such as a road, buildings, railway or even a waterway. During the entire process, drilling fluid is pumped through the drill rods and out through the drillhead. This specialised drilling fluid mixers with the cuttings (ground formation) to form a drill slurry which helps stabilise the hole, suspend cutting & prevent frac-outs to name a few. Once the drillhead enters the exit pit, which has been constructed at the other end of the bore path, the pilot bore has been completed.
2. Reaming Process
Once the pilot hole is complete, the drillhead is removed and a back reamer attached to the drill string. The reamer is then slowly pulled back through the hole whilst being rotated. As the reamer enlarges the hole, the cuttings again mix with the drilling fluid being pumped through the drill rods to help stabilise the hole and ensure flow continues to the exit pit. Several different size reamers maybe required during the drilling process to bring the borehole to its designated size.
3. Product Installation
Once the bore hole has been enlarged to its correct size and the hole is cleaned out, the product is connected to the reamer via a pipe puller, several metres of chain and swivel. As the product is being pulled back through the bore hole, drill slurry is forced into any voids that may a have been produced around the product. This is where the correct drilling additives used are so important. Once the product has entered the entry pit it’s disconnected from the drill string, HDD machine is removed, site returned to its original condition and all open pits made safe including fencing.
Only minimal disruption is caused to all surface movements and structures when using Trenchless technology.
No need to excavate hard surfaces such as roads. Reducing disruption to traffic flow
Constructs a bore hole under the roots of trees and plants thus causing minimal disturbance to vegetation.
Preferred method for installing products under rivers and waterways thus minimising bridge modification and construction of overhead cables.
Safer to the public as no long trenchers are required.
Multiple products can be installed in a single bore hole.
Minimal visual effect to residence while construction process is taking place.
Time on the work site can be shortened.
Can be steered horizontally and vertically en-ambling the bore hole to navigate through existing structures and services.
Pipe Bursting
Pipe bursting information will be listed here.
Microtunnelling and Pipe Jacking
Microtunnelling information will be listed here.
Pipeline Condition Assessment and Rehabilitation
Pipeline Condition Assessment and Rehabilitation will be listed here.
