Equipment provided by UAE-based equipment supplier Apollo Techno International FZCO was recently employed on a gas main diversion project at Emirates Road E-611 close to Sharjah in the United Arab Emirates (UAE).
The work was required as part of a road widening project for the expansion of 2-way road which will ultimately be 60 m wide and 12 m deep. The existing live SEWA gas main runs at just 6 m depth and had to be relocated to allow for the greater depth of the new roadway. The new main required the construction of a new pipeline near Khorfakan road.
The client for the project was Government of Sharjah-Road & Transportation Authority-(SRTA) with Equilibrium Engineering Consultancy as the project consultant and Astra Engineering & construction L.L.C as the main contractor.
With local ground conditions comprising mixed ground including fine to coarse grain very dense silty sand from surface to a depth of about 14 m and very weak, thickly bedded sandstone from 14 m to 20 m depth, it was decided that best option for installation of the new culvert to carry the gas main was the use of horizontal directional drilling (HDD).
The HDD work was ultimately awarded to trenchless contractor, Hydrotech Engineering Co. L.L.C – NDRC Division. HDD was selected as the preferred option as it is often the most cost-effective, quick and more sustainable method which also creates less disruption for stakeholders.
This option was also well-suited to the project due to the available access at the side of the State Highway which enabled to contractor to keep traffic management to a minimum which reduced public disruption. It also offered increased productivity relative to any potential trenched installation option with significant cost and time savings
DRILLING OPERATIONS
The drilling rig selected for the work by Hydrotech Engineering was an Apollo A2000R-120T from UAE-based equipment supplier Apollo Techno International FZCO. The navigation system used was a DCI, Falcon F5 with a 19 in beacon and IGPS module which allowed greater accuracy over the pilot bore and a better final as-built upload for the client.
All underground tooling was supplied by Inrock Industrial with the drilling fluid being a bentonite mixing system, an Apollo MT 80 – 2,100-gallon unit.
The project required the installation of a pipe over some 293 m which comprised a 30 in (760 mm) diameter, 15 mm wall-thickness Carbon steel pipe API 5L.Gr.X60 for the SEWA Natural Liquefied Petroleum Gas line.
After the completion of the pilot bore, several stages of reaming were required to enable the new pipeline to be successfully installed which included the use of rod recycling and Fly Cutter reamers staring at 18 in (460 mm) diameter and staging upwards through 24 in (610 mm), 30 in (760 mm), 36 in (915 mm) and 42 in (1067 mm) diameters. This was followed by the use of a Barrel reamer of 36 in (915 mm) diameter for backwashing and the pipe pulling operation.
Hydrotech Engineering commenced the drilling operations with mobilisation of the drilling machine and other accessories on 30 January 2022. The pilot bore started on 31 January with completion 1 February.
The up-sizing of the pilot bore with the multiple reaming stages commenced on 2 February and was completed on 15 February. Backwashing and pipe pulling commenced on 16 February with the pipe pulling starting immediately after as a continuous process on 17 February. The pipe pull was successfully completed on 18 February.
Commenting on the installation a representative of Hydrotech Engineering said: “We had worked near this area before with the same mixed ground conditions, so local knowledge gave us an edge over our competitors to win and successfully deliver this project.”
For Apollo Techno International FZCO, Subhash Sadashivan, Sales Director added: We have been able to gradually build our reputation since our inception in 2018. Our customers have shown immense faith and confidence in our product and we stand by our customers at all times. A2000R (120T Rig) was a proud moment for our team as Hydrotech Engineering believed in our product and our expertise. We were thrilled to see first project of A2000R completed in style.
