Trenchless Technology HDD drilling machines and piercing tools

HDD class: 4 - 6 tons, manhole machine

Pit launche machine out of a manhole - the MINI-JET MJS 1600

    Imagine being able to use existing sewer manholes to lay networks for electricity, gas and water without the need to dig up roadways or front gardens of private properties.

    Swiss producer of trenchless pipe and cable laying equipment TERRA AG has developed such a manhole HDD drill that is able to undertake directional bores from manhole to manhole and from manhole to all near-by homes. At 0.8 m (2.5 ft) depth you can lay telephone cables, at 1.20 m (4”) depth fresh water lines, and at 1.60 m (5 ft) depth gas or power lines.

    This innovative pipe laying method was developed over a 2 year period in close co-operation with the French water supplier SADE.

    The TERRA MINI-JET MJS 1600 is a manhole HDD drill for directional bores in lengths up to 50 m (165 ft) with a minimum turning radius of 15 m (50 ft). The directional bore can be reamed in several steps up to 300 mm (12”) even in hard ground. The TERRA MINI-JET MJS 1600 is equipped with a torque of 1600 Nm (1200 ft.lbs) and thrust and pull back forces of 60 kN (6 tons, 13’200 lbs).

Pit launche machine out of a manhole - the MINI-JET MJS 1600
Pit launche machine out of a manhole - the MINI-JET MJS 1600

Operation form a manhole

    The MJS 1600 can drill from manholes with an internal diameter of 1.0 m (3.3 ft) and can fit through manhole entrances of just 0.62 m (25”). Where the entrance is smaller than this, the manhole cover frame can be removed. First the drill’s bed frame is lowered into place in the manhole and tightened hydraulically in position, thereafter the manhole drill is lifted vertically through the manhole cover and bolted onto the bed frame. Drilling and back reaming takes place with bentonite drilling fluid pressure of 0-55 bar (0-800 psi) and drilling fluid volumes of 0-38 ltr/min (0-9 gpm). This makes the TERRA MINI-JET MJS 1600 a small but extremely effective horizontal directional drilling (HDD) machine.

Operation form a manhole
Operation form a manhole

The Operator's Stand

    The entire operation of the TERRA MINI-JET MJS 1600 is controlled from the surface where the operator along with the control station, rod magazine and rod lift are positioned.

    There is no requirement to enter the manhole during drilling and back reaming work. The operator inserts a new drill rod into the rod lift. The rod lift transfers it down into the manhole and positions it in the drilling machine.

    The new drill rod is screwed into the last drill rod. Inductive sensors make this operation possible even where the operator does not have a view into the manhole. The rod lift may also be positioned at an angle over the drilling machine where the manhole entrance is not located directly on top of the drilling machine.

The Operator's Stand
The Operator's Stand

Kubota Diesel Power Pack

  1. with 3 cylinder KUBOTA Diesel engine with 24 kW (33 HP)
  2. the Diesel engine operates at 2’500 r.p.m.
  3. with 2 independent hydraulic circuits
    56 ltr/min @ 175 bar (15 gpm @ 2'500 psi) for the pit frame
    28 ltr/min @ 125 bar (7.5 gpm @ 1'800 psi) for the mixing + pumping station
  4. box for documents
  5. large oil cooler with 6.4 kW cooling power, allows even ropical and desert operation
  6. service friendly
  7. environmentally friendly
  8. optinal with particulate filter
  9. 12 Volt plug with 5 A (60 W)

Kubota Diesel Power Pack
Kubota Diesel Power Pack

Mixing and Pumping Station

  1. with separate 1'100 ltr-tank (290 gal) for Bentonite or Ejactomer
  2. with support plate for 2 bags of Bentonite each 25 kg (50 lbs)
  3. the Bentonite can be easily filled into the funnel mixing pump with 800 ltr/min (210 gpm)
  4. injector (venturi jet)
  5. 1'100 ltr (290 gal) of drilling fluid are mixed with Bentonite within 4 minutes high pressure drilling fluid pump of FMC
  6. maximum drilling fluid volume: 38 ltr/min (10 gpm)
    maximum drilling fluid pressure: 55 bar (800 psi)

Mixing and Pumping Station
Mixing and Pumping Station


Technical Data

Technical Data

*   Depending on ground conditions
** Depending on drill rod size
Technical specifications can be changed without previous notice.
pullback force
6 to (60 kN)
13'200 lbs (6.6 US tons)
thrust force
6 to (60 kN)
13'200 lbs (6.6 US tons)
driving power
24 kW (33 PS)
24 kW (33 HP)
torque, 1st speed
1600 Nm
1200 ft.lbs
torque, 2nd speed
drill rod rotation speed, 1st speed
0-115 U/min
0-115 rpm
drill rod rotation speed, 2nd speed
drilling fluid volume
38 l/min
10 gpm
maximum drilling fluid pressure
55 bar
800 psi
drilling speed - quick gear
10 m/min
33 ft/min
1.5 m/min
5 ft/min
noise emission in 7 m distance
noise emission at operators ear
pilot bore diameter
Ø 60 - 100 mm
Ø 2.4" - 4"
maximum backream diameter*
Ø 260 mm
Ø 10"
maximum drilling length *
40 m
130 ft
drill rods, length
0.39 m
1.28 ft
drill rods, diameter
Ø 47/30 mm
Ø 1.85"/1.2"
minimum turning radius**
50 ft
Dimensions pit cradle LxWxH
1 x 0.55 x 0.80 m
3.3 x 1.82 x 2.64 ft
Dimensions LxBxH Control Station
1.65 x 0.55 x 2.31 m
5.45 x 1.82 x 7.62 ft
weight of the pit cradle
300 kg
660 lbs
Weight Controll station
170 kg
560 lbs


TERRA AG für Tiefbautechnik - Hauptstrasse 92 - 6260 Reiden - Schweiz - Tel. +41 62 749 10 10 -