Penetrometer Penfeld

The penetrometer Penfeld is a geotechnical measuring device. Once in position on the seabed, it takes measurements in the sediment using a rod fitted with instruments.

The penetrometer’s maximum working depth is 6000 m. It features a rod which penetrates the sediment to a depth of 30 m. The rod is 36 mm in diameter and is wound around a 2.20 m diameter drum. It is straightened during penetration using the coiled tubing technique.

A bearing cable connects the device to the vessel. It is powered by pressure-equalizing lead batteries.

Technical characteristics

• Maximum working depth: 6000 m
• Maximum penetration depth of the rod: 50 m
• Weight in air: 50 m model = 9.3 t / 30 m model = 6.3 t
• Weight in water: 50 m model = 7 t / 30 m model = 4 t
• Rod equipped with measuring tip
  • CPT tip
  • VP tip
  • Rod diameter: 36 mm
  • Penetration force: 5 t
  • Withdrawal force: 8 t
  • Power: lead batteries
  • Control: bidirectional acoustic link
  • Range: A penetration of 150 m to 200 m per dive (depending on the condition of the batteries and the type of sediment).
  • Inclination: 8° maximum