Integrated . Smart . Safe

Specialists in the installation of pipelines and conduits by the Horizontal Directional Drilling (HDD) method.

HDD Method

HDD is a trenchless method of installing pipelines and conduits under obstacles such as rivers, roads, railways, coastal shorelines / landfalls and other areas where open-cut excavations are not feasible or desirable for constructability, economic, social or environmental reasons.

Benefits of HDD

HDD has many benefits over the open-cut method, including: much reduced impact on the natural environment, little or no disruption to road and river traffic , less disturbance to local communities , lower risk of damaging existing utilities, greater depth of cover offering better protection to pipelines and conduits being installed, and a faster and more cost-effective method of construction.

Types of HDD Crossings

HDD crossings generally fall into 3 broad categories:


  • Onshore:  these are the most common types of HDD crossing, involving the installation of pipelines and conduits under obstacles such rivers, roads, railways, airport runways as well as congested or environmentally sensitive areas.
  • Onshore – Offshore:  the installation by HDD of the landfall / shore crossing sections of subsea pipelines and cable conduits as well as outfalls and intake lines.
  • Offshore: on occasion there may be a requirement to install a new pipeline under a shipping channel or across existing pipelines and cables offshore where the amount of vertical separation required can only be achieved by HDD. 

HDD Process

During the HDD process a pilot hole is first drilled along a predetermined path between pre-determined entry and exit points. The pilot hole is then enlarged in a single or multiple steps (reaming passes) to accommodate the pullback of the product / carrier pipe into the enlarged hole.

The HDD process may be implemented in different ways depending on various factors including site conditions, environmental considerations, geological conditions, technical specifications, and the like. TIPL is able to analyse, evaluate, design and implement the most suitable HDD methodology for a particular project.

Our Capability

With our comprehensive fleet of HDD rigs, ranging in size from 35T to 340T pull capacity, managed and operated by highly skilled and experienced personnel, TIPL has the capability to install crossings of all sizes , from small diameters across short distances up to large diameters over lengths exceeding 2500m, through all kinds of geological conditions from very soft ground (clays, silts, sands) to hard rock.

In addition to conventional onshore crossings TIPL is able to undertake the more complex, challenging projects, including landfalls / shore crossings and offshore crossing installations on a full EPC delivery basis. By combining resources with our partners, Kim Heng Marine & Oilfield Pte. Ltd., we can provide a complete integrated HDD package including specially designed, fit-for-purpose barges and support vessels that may be required to support the HDD operation. On certain projects we may also include site preparation and pipe string fabrication works in our scope.

On offshore windfarm projects, in addition to the HDD works, we have the capability to support our clients with the nearshore cable pulling operations, using our fit-for-purpose support barge spreads. Our barges can be easily modified and set-up to meet clients’ requirements.