The bell-type device for determining gas permeability 04315

The bell-type device for determining gas permeability 04315 is designed to determine the gas permeability of wet sands and wet, dry or hardened samples of molding and core sands in accordance with GOST 23409.6-78.
The device is used for use in workshop and factory laboratories of molding materials and mixtures, in laboratories of research organizations. The device for resistance to climatic influences corresponds to the UHL version, product placement category 4.2 in accordance with GOST 15150-69.
The principle of operation and composition of the device.
The principle of operation of the device is based on passing air through the test sample and fixing the pressure drop under it.
A tank is fixed on the base of the device, inside which a tube is installed, which is an air duct and at the same time a guide when lowering the bell. The bell is thoriated by weight and generates a constant pressure of 980.7 Pa (100 mm H2O).
Distilled water poured into the tank serves as a water seal.
Air, passing through the nipple, enters under the test piece and passes through it. The resulting pressure drop under the sample is transferred to a tank with a colored liquid, which is fed to a pressure gauge, calibrated in gas permeability units.
The device is supplied with 2 nipples: DN 0.5 mm and DN 1.5 mm. The nipples are calibrated so that the time of passage of 2000 cm³ of air under a pressure of 980.7 Pa through a 1.5 mm nipple is 30 s, and after 0.5 mm - 270 s.
The manometer scale is graduated for each nipple separately.
If the gas permeability is less than 50 units, a nipple with DN 0.5 mm is used.