RU2457462C1 - Device for defining powder material fluidity - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: device comprises hollow cylinder and differs from known design in that its includes loading funnel with valve and seat made at its bottom for mounting on cylinder, weight retainer and pan with flanged edges fastened by adjusting screws, intake vessels and cylinder secured via pulleys mounted on crossbar fixed at struts and guide tube with weight displacing inside tube. Washer is arranged at tube bottom.

EFFECT: ruled out powder dusting, reduced consumption.

3 dwg

Description

The invention relates to the field of creating laboratory equipment and devices for determining the physicomechanical characteristics of powder materials and can be used in various industries: food, construction, chemical, engineering, etc. A known device for determining the fluidity of powder compositions: G. Schreiber, P. Porst. Fire extinguishing agents. M .: Stroyizdat, 1975. The installation consists of a reservoir into which 4 kg of powder is loaded. Using nitrogen, a pressure of 10 kgf / cm ^{2 is created in it} , after which the powder is discharged through a spiral tube about 6 m long, 8 mm in diameter into a vessel for receiving the powder. Installation is difficult to design and high powder consumption.

A known method for determining fluidity using a micro-ejector: A.N. Baratov, L.P. Vogman. Fire extinguishing powder formulations. M: Stroyizdat, 1982. 50 g of powder is loaded into the glass of the micro-ejector with a closed tap. Then, the head is closed and nitrogen of a given pressure is supplied, the passage valve is opened, and the powder is ejected through the tube through the diaphragm. The ejection time and powder residue are recorded. The test is carried out at different pressures in five measurements. The disadvantage of this method is the large volume of tests and the work with nitrogen under pressure.

A known method for measuring the fluidity of powder formulations in accordance with fire safety standards is NPB-170-98, based on measuring the mass flow rate of the powder when it expires from a test device such as a fire extinguisher under working gas pressure. The test powder is loaded into the fire extinguisher and sealing is performed. Then nitrogen or air is pumped to a pressure of (16 ± 0.5) atm. The charged fire extinguisher is subjected to vibration, after which the powder is released for 6 seconds and the valve is closed. The disadvantage of this method is the complexity in the hardware design: an additional vibration stand, a cylinder with air (nitrogen), an injection line into the fire extinguisher, and a high powder consumption are required.

The known "method for determining the fluidity of a hydrophobized fraction of ammonium perchlorate" according to the patent of the Russian Federation 2390756, IPC G01N 11/00, decl. 02/24/2009, which consists in filling the test powder with a cylinder mounted on a plate, slowly manually lifting the cylinder and fixing the diameter of the powder scattered in a circle. Disadvantage: the speed of raising the cylinder and the direction vector corresponding to the vertical depends on the subject performing the measurement. This method is selected as a prototype.

An object of the invention was to provide a device for measuring the fluidity of powdered materials, devoid of the above disadvantages.

The technical result consists in the fact that a device is proposed (Fig. 1), consisting of a pallet 1, a cylinder 2, to the beam of which 3 a cable 4 is connected via two blocks 5 to a load 6. The blocks 5 are mounted on a cross 7 mounted on three uprights 8 and a guide pipe 9, inside which the load is held, held in the initial and upper positions inside the pipe by a latch 10, which is inserted into the corresponding holes "a" of the pipe. The lifting speed of the cylinder is regulated by changing the diameter of the hole "b". To mitigate the impact of cargo on the surface of the pallet, a gasket 11 is provided. Pallet 1 is a plate 15 with a flange 12 around the perimeter. Flanging is used to prevent powder from spilling out of the device. The horizontal installation of the pallet is carried out by screws 13. At the bottom of the pallet, four receiving tanks 14 are installed in special guides, into which, after testing, the powder is swept through the holes provided in the pallet.

To prevent dusting of the powder during testing, the cylinder is enclosed in a casing 16. On the surface of the pallet (figure 2) seven concentric circles are marked. The minimum circumference corresponds to the installation location of the cylinder. To load the cylinder and to sweep the powder into the receiving containers in the casing, there is an opening closed by a shutter. To load the powder, a loading funnel is provided, as shown in FIG. 3, the free volume of which is equal to the volume of the cylinder. The loading funnel consists of a housing 17, a valve 18, a crosspiece 19 and a cap 20. The housing 17 is a conical funnel in the lower part of which a cylindrical socket is provided for mounting it on a hollow cylinder. On the upper flange of the housing there are two pins 21, designed to fix the crosspiece 19. The crosspiece 19 holds the valve in 18 in its original closed position. In addition, by turning the cross around the vertical axis, the powder that is poured into the body is aligned. The valve 18 is held on the cross by a cap 20 screwed onto the valve stem. By rotating the cap, the height of the valve can be adjusted. To lock the cap against spontaneous unscrewing, a screw 22 is provided.

Determination of fluidity of the powder is as follows. After the cylinder is installed so that its outer diameter is inside the small pan 1, the loading funnel is filled with powder and installed on the hollow cylinder 2. By lifting the loading funnel valve 18, the powder is poured into the cylinder 2 and after emptying the loading funnel, the valve 18 is set to its original position. Then the funnel is removed. The load 6 is fixed in the measurement position, the cover of the casing 16 is closed. Then the lock 10 is pulled out, the lock 10 is pulled out, the load 6 lifts the cylinder 2 upwards and the powder is scattered on the surface of the pallet 1. Then the cover of the casing 16 is opened and the fluidity is evaluated by diameter reached by crumbling powder.

A positive factor in the application of the proposed device is a more accurate determination of fluidity, due to the constant speed of raising the cylinder, which is ensured by the selection of cargo and regulation by changing the diameter of the hole "b"; tightness of the device, which eliminates dusting beyond, thanks to the presence of a protective casing.

The proposed device for determining the fluidity of powdered materials was tested with a positive result in FSUE "NIIPM".

Claims (1)

A device for determining the fluidity of powdered materials, comprising a hollow cylinder, characterized in that it includes a loading funnel with a valve, in the lower part of which there is a socket for mounting on the cylinder, a latch that holds the load, and a perimeter flange pallet secured with adjusting screws, receiving containers and a cylinder, which, through blocks mounted on a crosspiece, mounted on racks and a guide pipe, is attached by a cable to a load moving inside the pipe, a puncture is fixed in the lower part of the pipe ka.

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