The HTH Gravity Corer

70 mm or 90 mm gravity corer

The principal is identical between the two versions, only the tube diameter differs. The 90 mm corer has a tube with 90 mm outer diameter. The samples collected is larger compared to the 70 mm corer. Both corers come with 50 cm long tubes as standard, but tubes can be tailored up to one meter.

The samples are effectively 40 centimeters as a maximum, with the standard tube.

The Principal
You can vary how far the corer penetrates into the sediment by selecting one or two of the rings furthest down on the corer. The corer is lowered until it is 0.5-1m above the sediment surface, when pause for about 10 seconds to allow the corer to stop oscillating and/or rotating. The corer is lowered until a light tug on the cable is felt, when the closing mechanism is released. When the corer is pulled up, the piston needs to be put in the bottom of the tube before lifting it out of the water. The tube is then removed from the corer and placed with the piston on the extruder rod. By releasing the lock you can easily evacuate superfluous water at the top and manually move the core tube downwards until the sediment-water interface is a few centimeters below the top of the tube. Then the lock is fixed and you can attach the  the scraper platform on the top of tube. Samples are pressed out by turning the extruder's bottom, one turn 360˚ = 5 mm. Scrape the samples into a suitable container.

Download a leaflet in PDF here

 

The HTH Super Corer

90 mm tripod gravity corer

The Super Corer is the alternative when you need samples up to 1 meter with perfect results. It is a tripod corer with a 90 mm tube, with a main weight of 16 kg, and optional weights of another 15 kg. It is based on the research made at the University of Umeå and the team headed by professor Ingemar Renberg.

The Principal
You can vary how far the corer penetrates into the sediment by mounting the additional weights. Attached to the tripod is a ball clamp which allows the corer tube to move downwards when the tripod has set on the bottom, but closes when the corer is lifted. The sample is not only pushed into the tube, but also pulled by a piston placed on the top of the tube. This allows meter-long samples to be drawn, with very high reliability giving excellent return on every sample session.

When the corer is lifted, the tube is then removed from the corer and placed with the piston on the extruder rod. By releasing the lock you can easily evacuate superfluous water at the top and manually move the core tube downwards until the sediment-water interface is a few centimeters below the top of the tube. Then the lock is fixed and you can attach the  the scraper platform on the top of tube. Samples are pressed out by turning the extruder's bottom, one turn 360˚ = 5 mm. The extruder is identical to the 90 mm HTH Corer.

Take a look at the PDF leaflet here.

 

Rental of the HTH Corers
The HTH Corers can now be rented per day or week. This offer is available for customers within EU only and is limited to the HTH 90 mm gravity corer and the HTH Super Corer. The possibility to rent the a corer is an excellent opportunity to cover specific assignments or to test the equipment prior to purchase. Please check prices under the "price list" tab.