Cable-tool samples

Cable tool u 1000 M,R,I Satisfactory sampling fluid levels easily detected drilling can be slow... 

The field vane shear test can be undertaken in boreholes formed by cable tool and wash boring methods. It is used to measure the shear strength of soft clays and clayey silts by means of a small vane, which is pushed into the soil. An increasing torque is applied to the vane until the cylinder of soil fails at which point the applied torque is noted. It is often the only way in which the shear strength of very soft soils can be measured reliably because of the difficulty of obtaining and testing truly undisturbed samples in such material. 

Continuous underway sampling using a deep-towed pump and a hose-cable can examine chemical patterns in the ocean that are nearly impossible to describe by other techniques. Growing realization of the importance of mesoscale features and oceanic fronts makes use of such sampling tools an essential part of oceanography. Effective data management must be an indispensable part of any deep-towed sampling system. 

OIT has been proved to be a useful diagnostic tool in assessing the extent of degradation in the polymer insulation of electric cables. Sample preparation and test conditions are parameters recognized to influence OIT results obtained by DSC. However, quantitative results on the variability of OIT as a function of these parameters have not been presented systematically in the literature. 

Impedance interfaces often provide the facility for automatically switching between measurements of the sample to be measured and measurements of a low loss calibrated reference capacitor (Figure 3.2.10). An ideal reference capacitor would have a completely flat response (constant capacitance) across the entire frequency range. This ideal capacitor cannot be achieved in reality since there will always be some parallel resistance in the capacitor even though this can, in practice, be an extremely high value. However, the difference between an ideal and nonideal capacitor is sufficiently small for most purposes and the reference capacitor is a very useful tool that can be used to quantify errors due to cables and instrument measurement errors. The deviation of the capacitor from its ideal response due to cables... 

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