What is Horizontal Directional Drilling?

Horizontal directional drilling (HDD) is a precision drilling technique that can be used for a range of underground installations. It is used when trenching or excavating is not practical, possible, or environmentally / economically viable. The drills are steerable and surface launched, and can create bores of up to 250mm over a distance of up to 250 metres.

Our drill rigs are capable of four way dimensional steering, which allows our operators to pilot bore a pre-determined route, any corrections or changes to be made where necessary on route. The hole is opened to the required size through an industry term called “back reaming”. Once completed, the product pipe is pulled back and the job is finished.

Directional Drilling Specialists

If you have a job that you think might require directional drilling, call or email us and we’ll be able to discuss whether moling or directional drilling might be able to save you money, time and hassle.

Advantages of Precision Drilling

There are a huge range of situations where using a directional drilling contractor will be preferable to digging trenches. Some of the advantages are:

  • Minimum disruption (to road, rail or pedestrian traffic)
  • Usually cheaper
  • Usually quicker
  • Relatively environmentally friendly (e.g. reduced CO2 emissions)
  • Small footprint for work (only entry and exit points)
  • Looks extremely professional
  • No scarring

Dry Drilling

Our directional drilling techniques are “dry” – a bit of a misnomer, because we use water! What it means is that we don’t use bentonite as a drilling lubricant, which has huge environmental benefits.

Find out more about our ‘dry drilling’ rigs

About Mole’s Drilling Rigs

At Mole Engineering we have 5 HDD rigs in total:

14 Tonne Drill Rig

Our 14 tonne drill rig provides thrust/pullback force with the capability of 3,800 ft-lbs of rotary torque, with a maximum rotary speed of 225 rpm. Weighing in at 20,000 lbs (247″ by 89″) and a working footprint of 10 metres, this drill is able to handle the toughest of jobs. Powered by a 125-horsepower John Deere turbocharged diesel engine with an onboard FMC mud pump capable of pumping 47 gallons per minute at up to 1500 psi. The rig uses a 10-foot drill stem that can carry up to 500ft of up to 350mm duct. This is an incredibly versatile drill rig and is perfect for network links, roads and many more.

6 Tonne Surface Launch Drill Rig

Our 6 tonne surface launch rig has around a 5 meter footprint making it very compact – the distance from the back of the rig to where the drill head enters the ground is about 5 meters. This rig has the capability to drill up to 120 meters.

6 Tonne Pit Launch Drill Rig

Our 6 tonne pit launch rig is 1.8 m long and requires a pit of around 4 square metres to be dug before launch. This rig is ideal for railway crossings, road crossings or similar, where you have not always got enough distance before the obstacle to reach the required depth using a surface launch rig. This rig is also ideal for drains, as our specialist engineers can drill from the site complex out into the road and directly down into the main manhole chamber, pulling in a new pipe without any excavations at all in the road. The pit launch rig is accurate to a fall of 1:100.

4X Drill Rig

Our compact and very manoeuvrable  4X Drill Rig is particularly useful in confined spaces and poorly accessible terrains, thanks to its small footprint and limited weight.

3 Tonne Drill Rig

Our 1.1m, 3 tonne rig must be one of the smallest rigs in the country. It is a small rig with 1/3 meter rods but has the capability of drilling in up to 6 inch pipe for up to 20 meters – ideal for road crossings, drilling under houses or drain connections. We often use this specialist directional drilling rig in place of a mole (for example when using a 63mm or 75mm mole to put 63mm piping or 2 1/2 inch ducting across a road). We prefer to use this compact drilling rig because it has total capability steering and tracking, so we know exactly where we are going! It may take a little bit longer to set up but the risks are lower, the job is quicker and the customer is happier!