Denison core barrel

DENISON CORE BARREL

The Denison core barrel is a triple-tube swivel type corebarrel, with a shoe with a sharp cutting edge threaded onto the inner barrel and extending below the cutting teeth of a tungsten corebit.

The length of the corebit must be changed to alter the amount by which the shoe extends below the corebit. According to Hvorlev (1949) and Lowe (1960) a 50-75 mm inner barrel protrusion is suitable for relatively loose or soft soils, whilst the cutting edge should be flush with the corebit in'very stiff, dense and brittle'soils. The Denison corebarrel uses a "basket" type spring core catcher, where a number of curved, thin, flexible springs are fixed to a base ring by rivets, or by welding.

EFFECTIVE IN DIFFICULT FORMATIONS

The Roschen Denison Sampler (core barrel) has proven its effectiveness and has withstood the test of time in providing geologists and geotechnical engineers with reliable undisturbed samples from a wide range of materials.

The Sampler successfully recovers undisturbed samples from hardpan, highly compacted formations including soft shales, cohesive soils, rare earths, kaolin, sands, sea bottom and other soft and easily eroded materials. This type of versatility accounts for the Denison's worldwide acceptance by soils engineers, foundation designers, contractors, architects and consultants.

THE DENISON PERFORMS WHERE OTHERS FAIL

Under certain conditions, ordinary thin wall samplers obtain undisturbed samples from clay, silts and organic (peat) deposits. But, when the deposit hardens, and extreme pressure is needed to collect the sample, the Denison does the job with ease. The Denison Core Barrel has proven that it is at its best when adverse conditions are encountered.

TRULY UNDISTURBED SAMPLES RECOVERED

The most important advantage of Acker Denison Core Barrel is that the samples obtained are not deformed or undisturbed during the recovery process. Such samples are truly undisturbed as defined in the generally accepted meaning of the term.

LARGER SAMPLES OBTAINED

Because of the size of the Denison Sample, sampling distortion is considerably less than that in samples from smaller, thin tube samplers. The larger Denison Sample can be trimmed in the laboratory to minimize the possibility of any slight deformation by wall friction or slight drag of the core retainer springs.

DESIGNED FOR USE IN NW CASING

The Roschen 2-15/16 inch (76.2 mm) Denison is the smallest Denison available and incorporates all the engineering refinements of the 4 larger sizes - yet having the added features of being considerably lighter and easier to handle in the field. The 2-15/16 inch Denison operates inside NW casing.