Infrastructure, Transmission Lines & Trenchless Technology

Horizontal Directional Drilling

SAT Company's specialized solution for safely routing pipelines, cables and underground utilities beneath natural and man-made obstacles without extensive surface disruption or route closure.

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01 Introduction to HDD Technology

Crossing Obstacles, Without Disrupting the Route

In civil and infrastructure projects, routing pipelines and cables beneath natural and man-made obstacles has always been one of the main engineering challenges. In the past, these operations were carried out using conventional methods such as open-cut excavation and boring (Boring) and pipe jacking (Pipe Jacking) which typically involved surface disruption, long execution times and high costs.

With the development of modern technologies and greater attention to environmental considerations, Horizontal Directional Drilling has emerged as one of the most efficient and precise methods for routing pipelines beneath obstacles.

This technology enables oil, gas, water and wastewater pipelines, as well as various cables, to pass underground without requiring road closures or surface excavation.

Horizontal Directional Drilling and Execution Equipment

02 History of Horizontal Directional Drilling

From Ancient Iranian Qanats to Modern HDD Technology

Horizontal Directional Drilling has roots in the traditional practices of ancient Iran. Similar techniques were used in qanat construction to convey water more than six thousand years ago. This traditional approach became a foundation and inspiration for the development of modern horizontal drilling technologies.

Before steerable drilling rigs were developed, oil, gas and water pipeline crossings were mainly executed using boring (Boring) and pipe jacking (Pipe Jacking) methods.

1971 The first Horizontal Directional Drilling operation in the United States, used to route a gas pipeline beneath a river approximately 550 meters wide.

1986 Use of this technology in Germany for crossing electrical cables and urban pipelines.

Today HDD has become one of the most efficient underground drilling technologies for installing cables, fiber-optic lines and fluid transmission pipelines.

03 SAT Company in HDD

Four Decades of Experience, A Pioneer in Localizing HDD Technology

With more than four decades of continuous activity, SAT Company has executed numerous projects in the oil, gas and petrochemical industries, including major obstacle and river crossings using Horizontal Directional Drilling.

The company has achieved Grade 1 qualification in oil and gas transmission lines and has received a commendation from the Managing Director of the National Iranian Gas Company.

The first HDD project carried out in Iran was completed in 1383 by SAT Company in cooperation with international partners, as part of the 24-inch North Ahvaz gas transmission pipeline project crossing beneath two rivers.

SAT Company is proud to have localized HDD technology in Iran. Without relying on foreign specialists, and while achieving significant foreign-currency savings under challenging sanctions, the company has procured and developed the required hardware and software equipment.

In this process, the expertise of Iranian specialists and leading professionals has been used to design and manufacture components and assemblies and to redevelop various software systems.

04 Horizontal Directional Drilling Rig

Advanced Equipment for Precise Route Execution

The steerable horizontal drilling machine, or Horizontal Directional Drilling Machine is among the most advanced and powerful drilling systems used worldwide.

The rig is equipped with auxiliary equipment including various drill bits, reamers, fly cutters in different sizes, drill pipes or rods, and a drilling-fluid preparation and pumping system.

Various Drilling Bits

Reamer / Hole Enlarger

Fly Cutters in Various Sizes

Drill Pipes & Rods

Drilling Fluid Preparation & Pumping System

Depending on site conditions, the horizontal drilling machine can operate over various lengths and accommodate pipelines ranging from 2 inches to 56 inches in diameter.

The rig's operating limits for pipeline diameter and length depend on several parameters, including required pullback force, pressure and torque. Therefore, geotechnical study results and the type and characteristics of soil layers must be considered when selecting the appropriate method and equipment.

05 Before Starting Field Operations

Precise Design Is Essential for Reliable Execution

Before Horizontal Directional Drilling operations begin, a series of carefully planned engineering activities is carried out to ensure the accuracy of the design and the reliability of execution.

Site Visit & Route Survey

Assessment of geographic conditions and identification of suitable locations for positioning the drilling rig (Rig Side) and the pipe assembly area (Pipe Side).

Geotechnical Testing & Depth Investigation

Drilling boreholes, identifying soil layers and preparing geological reports to select the appropriate drilling method and required equipment.

Route Plan & Cross-Section Profile

Designing the exact crossing path and determining the entry (Entry Point) and exit points (Exit Point) based on survey data.

Design & Layout of Execution Equipment

Preparation of site-layout drawings, positioning of equipment, power-supply systems, drilling-fluid pits and other supporting facilities.

06 Engineering Activities

Project Engineering, From Calculation to Final Approval

Engineering Studies & Technical Calculations

Calculation of pulling forces, stress analysis, buoyancy control and determination of technical execution parameters.

Preparation of Execution Documents

Including technical specifications, welding procedures, hydrostatic testing requirements, pipeline coatings and client-approved standards.

Schedule Planning & Weighted Progress Analysis

Preparation of a detailed schedule for drilling, installation and pipeline testing activities.

Final Review & Approval of the Execution Proposal

After completion of the studies, the execution plan is submitted to the relevant authorities for final review and approval.

07 Execution Process

Three Main Stages of HDD Execution

Horizontal Directional Drilling execution consists of three main stages carried out in a precise and continuous sequence.

Pilot Hole Drilling

Pilot Drilling

Initial drilling and controlled steering of the tool along the designed path while monitoring position, direction and drilling depth.

Hole Reaming

Back Reaming

Gradual enlargement of the borehole to suit the pipeline diameter and geotechnical conditions in preparation for the final installation path.

Pipeline Pullback & Installation

Pulling

Pulling and installing the pipeline through the prepared bore while controlling pullback forces and complying with project technical and safety requirements.

08 Advantages of HDD

Why Horizontal Directional Drilling?

Compared with conventional obstacle-crossing methods, Horizontal Directional Drilling offers significant technical, economic and environmental advantages.

Cost-effective execution with significantly shorter project duration compared with other methods

No need for casing when crossing beneath obstacles

Capability to operate at significant depths and in diverse ground conditions

Reduced surface disruption and minimal environmental impact

Smaller working footprint compared with open-cut methods

Minimal traffic disruption and urban disturbance in high-traffic areas

High safety with reduced risks associated with trench or excavation collapse

Precise control and steering of the drilling path from the surface

Reduced requirement for specialized personnel at the execution site

Intelligent, precise and reliable performance across various ground conditions

Reduced workspace requirements and improved operational efficiency

Contact Information

Contact us to discuss your Horizontal Directional Drilling project.

info@satcompany.ir ←

Head Office Address

Tehran, Ashrafi Esfahani Highway, north of Shahid Hemmat Expressway, Tabatabaei Street, Royal Building

Working Hours

Saturday to Wednesday, 8:00 AM to 5:00 PM

Phone & Fax

021-44446351-2
021-44446905-6
021-46041215
021-46041223