RU212881U1 - HIGH VISCOUS LIQUID MIXER WITH COMBINED SHAFT SEAL - Google Patents

Abstract

The utility model relates to devices for mixing high-viscosity liquids, namely high-viscosity liquids with a combined shaft seal. The main problem to be solved by the utility model is the inability to promptly repair and replace the elements of the combined seal in the known analogues, since the elements of the combined seal in analogues are placed on the part of the shaft located in the tank, so that the designs of the known combined seals do not provide for the possibility their operational repair directly at the installation site of the device for mixing a high-viscosity liquid. A device for mixing a high-viscosity liquid with a combined shaft seal contains a combined shaft seal, which is installed on the part of the shaft located outside the tank behind the connecting flange, and consists of a lip seal installed in series in the body, consisting of lip seals with sealing elements located in the cage, and a mechanical seals, consisting of a movable and fixed cages, an elastic element in the form of a spring, rotating and non-rotating contact rings. The technical result of the proposed utility model is to increase the operational manufacturability while increasing the duration of operation of the device for mixing a high-viscosity liquid. 2 ill.

Description

The technical solution relates to devices for mixing high-viscosity liquids, namely high-viscosity liquids with a combined shaft seal.

The prior art device for erosion of bottom sediments in a tank with high-viscosity oil or high-viscosity oil products [utility model patent RU 158798 U1, IPC B01F 15/00, B01F 7/00 (2006.01), publ. 01/20/2016]. The device is intended for washing out bottom sediments in a tank with oil or oil products, containing a housing with a shaft located in it, the end of which is equipped with a propeller and passes through a flange for connecting the shaft housing to a branch pipe on the tank, while the flange is connected to the shaft housing by a hinge that allows an angular rotation of the shaft housing around an axis perpendicular to passing through the longitudinal axis of the shaft, an electric drive for rotating the shaft, including an electric motor for rotating the shaft and a mechanical transmission, an electric drive for angular rotation of the shaft, including a kinematically connected electric motor for angular rotation of the shaft and a "screw-nut" gear installed parallel to the shaft on the outer side of the shaft housing with a displacement of the longitudinal axis of this transmission from the axis of rotation of the said hinge, elements of support and sealing of the specified shaft relative to the housing of this shaft, as well as a sealing unit for the housing of the specified shaft from the reservoir cavity, an electric motor for rotating the shaft and the electric motor The gate for angular rotation of the shaft is installed on the specified shaft housing with the possibility of angular rotation together with the shaft housing, and the output link of the said "screw-nut" gear is movably connected to the specified flange with the possibility of angular rotation of this "screw-nut" gear relative to the specified flange.

The disadvantage of analogue is the lack of protection of the mechanical seal. The reservoir fluid is constantly in the internal cavity of the mechanical seal, which, with the help of special rings ground to each other, prevents the outflow of this fluid to the outside at rest and during their mutual rotation. The internal cavity of the mechanical seal is filled with many parts moving relative to each other, the gaps between which are small. These gaps contain the reservoir fluid at all times. When mixing high-viscosity liquids in tanks, for example, fuel oil, abnormal and emergency situations may occur when the temperature of a high-viscosity liquid (fuel oil) drops below the maximum allowable value (for example, +40 ° C) and the liquid solidifies, turning into an amorphous mass. This mass is located in small gaps of the mechanical seal and practically glues together all its moving parts, including rings ground to each other. When the device is turned on, the mechanical seal is depressurized due to damage to the rings and the breakdown of many parts glued together. Abnormal and emergency situations in tanks with high-viscosity liquids occur quite often due to failures of heating systems, power outages, etc. After the normalization of the situation with the heating of the tank, it becomes necessary to turn on the known devices for mixing the liquid in the tank. After switching on, the known devices for mixing the liquid in the tank fail due to the breakdown of their mechanical seals.

The closest technical solution, selected as a prototype, is a device for mixing a highly viscous liquid and washing out its sediments in a tank [utility model patent RU 107707 U1, IPC B01F 7/08, B01F 15/00 (2006.01) publ. 08/27/2011], the seal assembly uses devices to supply a solvent (diesel fuel, kerosene, gasoline, etc.) into the cavity between the mechanical and lip seals, which prevents the sealing rings of the mechanical seal from sticking together and prevents the accumulation of paraffin deposits in the gaps and cavities near mechanical seal assembly.

The disadvantage of analogue is the impossibility of replacing without decommissioning the tank of damaged lip seals installed on the part of the shaft located in the tank. To replace a lip seal that has lost its tightness, it is necessary to completely pump out the fuel oil and take the tank out of operation.

The technical problem to be solved by the claimed utility model is the inability to promptly repair and replace the elements of the combined seal in known analogues, since the elements of the combined seal in analogues are placed on the part of the shaft located in the tank, in such a way that the designs of the combined shaft seals of known devices for mixing a high-viscosity liquid do not provide for the possibility of their prompt repair directly at the installation site (on the manhole cover of the tank) of a device for mixing a high-viscosity liquid.

The technical result of the proposed utility model is to increase the operational manufacturability while increasing the duration of operation of the device for mixing a high-viscosity liquid.

The task is achieved in that the device for mixing a high-viscosity liquid with a combined shaft seal contains a combined shaft seal, in which a lip seal is installed in series in the housing, consisting of cuffs with sealing elements located in the cage and a mechanical seal, consisting of a movable and fixed cages, elastic element in the form of a spring, rotating and non-rotating contact rings.

In this case, the combined shaft seal is installed on the part of the shaft located outside the tank behind the connecting flange.

In FIG. 1 shows the design of a device for mixing a highly viscous liquid and washing out its sediments in a tank.

In FIG. 2 - enlarged section of the shaft seal relative to the housing.

In FIG. 1 and FIG. 2, for clarity, the wall of the reservoir is shown by a dash-dotted line.

A device for mixing a high-viscosity liquid with a combined shaft seal (Fig. 2) contains a combined shaft seal mounted on a part of the shaft and located outside the tank behind the connecting flange 1. The combined shaft seal contains a lip seal 3 and a mechanical seal 4 installed in series in the housing 2. seal 3 consists of cuffs 5 with sealing elements 6 and a clip 7 holding them. Mechanical seal 4 consists of a movable 8 and a fixed 9 clip, an elastic element 10 in the form of a spring, rotating 11 and non-rotating 12 contact rings.

A device with a combined shaft seal operates as follows.

When the shaft is stationary, the sealing edge of the cuff 5 is pressed against the shaft being sealed under the action of elastic forces and creates an increased contact pressure in the contact zone, which prevents the penetration of liquid from the zone with increased pressure. When the shaft rotates due to the dynamic beating of the shaft, the presence of surface roughness and increased pressure in the sealed cavity, the thickness of the liquid film increases, and the liquid gradually penetrates into the cavity between the lip and mechanical seals. Under the action of the spring 10, the fixed cage 9 abuts against the movable cage 8, while in the friction pair, the rotating 11 and non-rotating 12 contact rings develop contact pressure.

When the lip seal 3 is destroyed, the device for mixing bottom sediments is stopped and, by moving the shaft forward, the channel for passing the medium from the tank is blocked and the destroyed elements that make up the combined seal are replaced (without draining the liquid from the tank), after which the device is put into operation again.

The location of the seal assembly on the part of the shaft outside the tank increases the convenience of repairing the device with a combined shaft seal while simplifying the maintenance of the combined seal without taking the tank out of service and pumping out a high-viscosity liquid from it.

Claims (1)

A device for mixing a high-viscosity liquid with a combined shaft seal, containing a combined shaft seal, in which a lip seal is sequentially installed in the housing, consisting of lip seals with sealing elements located in the cage, and a mechanical seal, consisting of a movable and fixed cages, an elastic element in the form springs, rotating and non-rotating slip rings, characterized in that the combined shaft seal is installed on the part of the shaft located outside the tank behind the connecting flange.

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