VIBROCORE: P-5 Rossfelder System

Vibrocoring is an efficient and versatile procedure for obtaining long, well-preserved cores in consolidated water-saturated sediments from wetlands, harbors, lakes and the deep ocean. It allows for deep penetration in a single deployment and a high core recovery where other approaches prove either inappropriate or impractical.

Gregg owns and operates the P-5 Rossfelder Vibrocore system. They are sturdy and powerful, yet light and compact. They can be airfreighted at minimal cost anywhere in the world to be operated from local vessels-of-opportunity or any of the boats and barges in Gregg’s marine fleet. Designed to withstand deep ocean pressures, rough seas and arctic cold, the submersible vibrocores are fully enclosed, easy to clean, and have also become tools of choice for retrieving cores in contaminated sediments and hazardous environments.

The P-5 Vibrocore houses a pair of vibrator motors in a contra-rotating configuration that doubles the vertical motion of the unit. The vibrocore can be operated with steel or aluminum core tubes with or without liners. In order to maximize the core recovery, the retention of the core is a factor as important as the penetration achieved. To this effect, Gregg’s vibrocoring systems incorporate a tight-sealing water-escape valve mounted within the vibrohead. A reusable plug-valve to fit the top of the core tube or a stainless-steel thinwall core nose with fingered core-catcher can also be used depending on the soil sediments to be collected.

Specifications:

Working depth: 600m (2000ft) water depth
Power requirements: 230 or 460V, 50-60Hz, 3ph
Average running amps (while vibrocoring): 9A (low setting), 14A (high
setting) at 230V.
Force (1kN = 225lbs): 32kN to 48kN at 60Hz, 21.8kN to 32.8kN at 50Hz
Vibration Frequency: 3450vpm at 60Hz, 2850vpm at 50Hz
Typical core tube length/diameter: 6.0m/102mm (20ft/4.0”)
Typical shipping weight: 590kg (1300lbs)

Sampling Technique:

Core tube is driven into the sediment by the force of gravity, enhanced by
vibration energy (created by vibra-head at top of tube)
Vibrations cause a thin layer near the inner and outer tube walls to
mobilize, reducing friction and aiding in penetration
Reduces effect of “plugging” or “rodding”
Useful for deeper cores (>1m) OR where sediment consists of very compacted or large grain material (e.g. gravel)

	ADDITIONAL INFORMATION
	View/Print::	See Also:
	Vibracore Datasheet	Alpine Vibracore System

VIBRoCORE: P-5 Rossfelder system

Specifications:

Sampling Technique: