Buy ground-penetrating hammers – GEO ground-penetrating hammers, Ø 48 to 130 mm, Tracto-Technik Grundomat, available as a single unit or as a complete set with a compressor, direct from a specialist retailer. A ground rocket (ground displacement hammer, soil rocket) drives house connections, cables and pipes under roads, driveways and gardens – without digging, without breaking up the surface, and without the need for restoration. We stock ground-penetrating hammers from GSK Baumaschinen in Hanhofen (GEO specialist dealer offering complete packages) and Kraus Baumaschinen in Frankenthal – with diameter, compressor requirements and scope of delivery specified in the listing.
Which ground rocket is right for your pipeline?
Ø 48–55 mm: For cables, conduit pipes and service connections up to DN 40. Operates with small compressors from 1.4 m³/min (Atmos PB 82 E, Kaeser M13, Atlas Copco XAS 38) – the entry-level and electrician’s package.
Ø 65–95 mm: For water, gas and cable protection pipes up to DN 63–75, drilling lengths up to 15–20 m. Requires 2–3 m³/min at 6–7 bar (Kaeser M17, Atlas Copco XAS 58/88).
Ø 110–130 mm: For pipes up to DN 90–110 (sewage service connections, multiple-pipe installations), 3–5 m³/min. The class for civil engineers and utility companies.
Oscillating head and long version: The movable oscillating head keeps the rocket on course and works its way through stones; the long version runs straighter and can be retrieved using reverse gear. GEO earth rockets come with an oiler and compressed air hose; the Tracto Grundomat 65S/75S models are the classic alternative.
Complete packages: Earth auger plus matching construction compressor (Atmos PB 82 E, Kaeser M13, Atlas Copco XAS 38-7) – perfectly matched, ready for immediate use. The guide ‘Choosing the Right Construction Compressor’ explains which compressor class suits which tool.
What we look for in second-hand earth augers
Head and housing: Wear on the head and oscillating head bearings; cracks and deformation on the housing; condition of the thread for accessories and expanders.
Striking mechanism: check the piston and cylinder for scoring; test the striking frequency during a trial run (connect to compressed air); check the forward/reverse switch; check lubrication – a ram that has run dry will show signs of seizure.
Accessories: Oiler, compressed air hose (length, couplings), targeting device, launch mount, expander, pulling head for pipes – a complete set saves several hundred euros.
Compressor: Check the rocket’s air requirement (m³/min at 6–7 bar) against the compressor’s capacity; insufficient air means insufficient impact energy. Use special organic oil for lubrication (to protect the ground).
| Diameter | Tube up to | Air requirement | Suitable compressor | Insert |
|---|---|---|---|---|
| Ø 48–55 mm | DN 40 | 1.4–2 m³/min | Atmos PB 82 E, Kaeser M13, XAS 38 | Cables, conduit, service connection |
| Ø 65–95 mm | DN 63–75 | 2–3 m³/min | Kaeser M17, XAS 58/88 | Water, gas, cable protection conduit |
| Ø 110–130 mm | DN 90–110 | 3–5 m³/min | Kaeser M31/M45, XAS 88/138 | Wastewater, multiple installations |
Brands and suppliers
Tracto-Technik (Grundomat) invented the ground rocket; GEO is the competitively priced alternative with a swivel head and a long version; Terra and Kaeser round off the range. Our stock comes from GSK Baumaschinen in Hanhofen (GEO earth rockets Ø 48–130 mm, sold individually or as a package including a compressor, accessories and bio-oil) and Kraus Baumaschinen (new and used Tracto Grundomat units). Filter by manufacturer and condition; you’ll find the diameter in the title.
Frequently asked questions about ground rockets
What compressor do I need for a ground rocket?
Depending on the diameter, 1.4 to 5 m³/min at 6–7 bar. For Ø 48–55 mm, a small compressor such as the Atmos PB 82 E or Kaeser M13 is sufficient; for Ø 110–130 mm, a Kaeser M31/M45 or Atlas Copco XAS 88 is required. Our complete packages are already optimised for this.
How far and into what type of ground can an earth rocket be fired?
Typically 10 to 25 m per shot in compressible soils (sand, loam, gravel up to fist-sized). Rock, large stones and heavily water-saturated soils present limitations – in such cases, flushed drilling or open construction methods are required. The oscillating head helps with stony ground.
What diameter do I need for my pipe?
The rocket should be about 20–30 per cent larger than the pipe’s external diameter so that the pipe can be pulled through: DN 40 → Ø 55, DN 63 → Ø 75–95, DN 90–110 → Ø 130 or an expander. For cables, Ø 48–55 with a conduit is sufficient.
How much does a ground-penetrating rocket cost?
New GEO ground-penetrating rockets cost in the low to mid four-figure range depending on the diameter; complete packages including a compressor are in the five-figure range; second-hand Grundomat models are correspondingly cheaper. A set usually pays for itself with the first instance of avoiding roadworks.
Can I lease ground-penetrating rockets or finance them via hire purchase?
For complete packages including a compressor, you can submit a non-binding enquiry regarding leasing or hire purchase. You can discuss the terms with the dealer or their finance partner; the purchase and payment are handled directly between you and the seller.
An overview of all types: Construction machinery · Suitable air supply: Construction compressors · More on pipeline construction: Cable-laying technology