Development of a compact hydraulic drilling system for geothermal drilling at confined and indoor sites.
FlexDrill GmbH
Perfektastraße 87/15, 1230 Wien, ÖsterreichNew on Amplifa
About FlexDrill
FlexDrill is a Vienna-based engineering office (GmbH) developing a compact hydraulic percussion drilling system for geothermal drilling as part of ground-source heat pump projects. The development goal is boreholes up to 200 m deep with a footprint of 1 m², indoor use (basements, courtyards, underground garages), and drilling completed within one day. The system consists of a trailer-mounted unit (diesel-powered pump, water tanks, filtration, control system), a spool unit with flexible hydraulic hose and HDPE casing, a compact drilling rig, and a downhole assembly with a hydraulic percussion mechanism. Drill cuttings are transported away via circulating drilling fluid and filtered. The hardware is iteratively developed and tested on the high-pressure test rig in Vienna, together with drilling companies, research partners (TU Wien, AEE INTEC, Geothermie Österreich) and the industrial partner TERRA Umwelttechnik. The company is in the pre-commercial stage; technical validation and field trials are still ongoing.
- Site
- Wien
- Processes
- Compact hydraulic percussion drilling (geothermal boreholes for ground-source heat pumps), Trailer unit – diesel-powered pump, water tanks, filtration, control system, Spool unit – carries flexible hydraulic hose and HDPE casing, Drilling rig – compact 1m² unit, pipe guidance, drilling progress, Downhole assembly – hydraulic percussion mechanism (rotation + percussion downhole), Drill cuttings removal via circulating drilling fluid, filtration, Indoor geothermal drilling (basements, courtyards, underground garages), Engineering Services
- Materials
- HDPE (casing), Steel pipe, Rock / formation, High-pressure water, Diesel (fuel for trailer unit), HDPE casing
- Industries
- Geothermal energy / ground-source heat pumps, Construction and drilling technology, Decarbonization of building heat
- 01
System architecture & CAD (engineering)
- 02
Prototyping in Vienna workshop
- 03
Testing on high-pressure test rig
- 04
Field trials (planned)
- 05
Market launch (planned)
System Components & Materials
HDPE casing
Flexible pipe material for casing the borehole, replacing conventional rigid steel pipe strings.
Steel pipe
Conventional material for drill strings, which is replaced in the FlexDrill concept by flexible hose and HDPE.
High-pressure water
Transmits hydraulic energy to the downhole mechanism and serves as drilling fluid to remove drill cuttings.
Site
Vienna
ATHeadquarters, development, workshop & high-pressure test rig
- Materials
- Steel, HDPE, high-pressure water
- High-pressure test rig
- FlexDrill drilling system (prototype)
- Trailer unit (diesel-powered pump, water tanks, filtration, control system)
- Spool unit
- Drilling rig
- Downhole assembly (hydraulic percussion mechanism)
Industries
Processes & technical limits
| Processes | Tolerance | Max. part | Weight | Lot size | Materials |
|---|---|---|---|---|---|
| Compact hydraulic percussion drilling (geothermal boreholes for ground-source heat pumps)Engineering | – | 200 m (target drilling depth) × 1 m² (target drilling footprint) | – | – | Steel pipes (conventional, comparison), HDPE casing, High-pressure water (drilling fluid), Rock/formation |
| Trailer unit – diesel-powered pump, water tanks, filtration, control systemEngineering | – | – | – | – | Diesel, Water |
| Spool unit – carries flexible hydraulic hose and HDPE casingEngineering | – | – | – | – | HDPE |
| Drilling rig – compact 1m² unit, pipe guidance, drilling progressEngineering | – | – | – | – | – |
| Downhole assembly – hydraulic percussion mechanism (rotation + percussion downhole)Engineering | – | – | – | – | High-pressure water |
| Drill cuttings removal via circulating drilling fluid, filtrationEngineering | – | – | – | – | Drilling fluid/water, Drill cuttings |
| Indoor geothermal drilling (basements, courtyards, underground garages)Engineering | – | 200 m (target depth) × 1 m² | – | – | – |
6 Anlagen & Maschinen
| Machine | Manufacturer / model | Quantity | Working area | Year built | Site |
|---|---|---|---|---|---|
| Compact hydraulic percussion drilling system (FlexDrill, in development) | FlexDrill GmbH FlexDrill | 1 | 1 m² drilling footprint, target depth up to 200 m | – | Vienna (development, high-pressure test rig) |
| Trailer unit (diesel-powered pump, water tanks, filtration, control system) | FlexDrill GmbH | – | – | – | Vienna (concept) |
| Spool unit (flexible hydraulic hose, HDPE casing) | FlexDrill GmbH | – | – | – | Vienna (concept) |
| Drilling rig (compact 1 m² unit over the borehole) | FlexDrill GmbH | – | 1 m² | – | Vienna (concept) |
| Downhole assembly (hydraulic percussion mechanism) | FlexDrill GmbH | – | – | – | Vienna (concept) |
| High-pressure test rig | – | – | – | – | Vienna |
Additional services
History
- 2026
Awarded the LIMES Zukunftspreis 2026 of the Energiepark Forschungsstiftung (€25,000, renewable energy); winner of City Pitch 2026 Graz (Energy & Climate Protection)