Device for determination of rock filtration coefficient under pressure

Abstract

In laboratory practice up to the present time for determination of filtration coefficient of cohesive rocks two types of devices are used: N. V. Kolomensky and PV - Znamensky and Haustov's design. But these devices are designed either for small heads expressed in fractions of atmosphere (PV) or for cores of large diameter (N.V. Kolomensky device). The device described in this article is designed and actually applied by us for determination of filtration coefficient of cohesive rocks under pressure of 2-3 atm at core diameter of 35 mm. Some features of the E. E. Kerkis device, designed for determination of the filtration coefficient of loose soils, were partially used in the construction of the device. The device for pressure filtration (Fig. 1) consists of a cylinder 5, two flanges 1 with grids 2, clamping rings 3 and rubber gaskets 4. A core with a diameter of 35 mm and a height of 20 mm is loaded inside the cylinder. The gap between the conical part of the inner surface of the cylinder and the core is filled with resin. When selecting the resin, it should be borne in mind that excessive plasticity may cause the resin to float on the bottom surface of the core, which will reduce the filtering surface. Therefore, a harder resin should be used.