CN102494855A - Leakage detection device for large-diameter rotary sealing shell of magnetic liquid - Google Patents

Abstract

The invention provides a leakage detection device for a large-diameter rotary sealing shell of a magnetic liquid, belonging to a sealing field of mechanical engineering and solving the problem of the leakage detection of the large-diameter rotary sealing shell of the magnetic liquid. An opening end of a mandrel (12) of the device is welded at the center of the inner wall of a base (1). A shell (2) is in a split type structure and is fixed by a bolt. A left pole shoe (3), a permanent magnet (4) and a right pole shoe (5) are sequentially arrayed to form a sealing subassembly to be pushed into the shell; and sealing glue is coated on a jointed surface between an end cover (10) and the shell and the end cover is in threaded connection with a thread on the shell so as to fix the end cover on the shell. A first rubber sealing ring and a second rubber sealing ring are respectively arranged between the left side face of the left pole shoe and the hole wall of the shell (2), and between the outer circular face of the right pole shoe and the hole wall of the shell (2). A nitrogen gas cylinder of a gas input and pressure detection device is connected with a joint (7) on the end cover (10) through a pipeline; a valve (9) is installed on the pipeline and a pressure gage (8) is arranged between the valve and the joint.

Description

Leak detection device for large diameter magnetic liquid rotary sealing shell

technical field

The invention belongs to the field of mechanical engineering sealing.

Background technique

As a new type of functional material, magnetic fluid has been widely used in the field of mechanical seals in recent years because it has both the fluidity of fluid and the response characteristics of magnetic materials to magnetic fields. Compared with other traditional sealing technologies, the magnetic liquid sealing technology has the advantages of zero leakage, long life, no solid friction, and convenient disassembly and maintenance. Due to its large diameter (D≥600mm), the large-diameter magnetic liquid rotary sealing device generally adopts a split structure. Therefore, it is particularly important to inspect the shell when inspecting whether the leakage rate meets the design requirements. There is no report on leak detection of the shell of the large-diameter magnetic liquid sealing device at present.

Contents of the invention

The technical problem to be solved by the present invention is that the existing large-diameter magnetic liquid rotary sealing device lacks a leak detection device for the shell, and a leak detection device for the large-diameter magnetic liquid rotary seal shell is provided.

The technical solution adopted by the present invention to solve its technical problems is:

A leak detection device for a large-diameter magnetic liquid rotary sealed casing, which constitutes the connection between the various parts of the device:

The base is a flat cap structure, the mandrel is a cylinder, and its open end is welded to the center of the inner wall of the base, and the mandrel and the base are coaxial to form the mandrel assembly of the base.

The shell is a split structure, and the two petals are connected and fixed by bolts, and the joint surface of the two petals is coated with sealant to form the shell.

The first rubber sealing ring is embedded in the concave groove on the outer circumference of the left pole shoe, and the second rubber sealing ring is embedded in the concave groove on the outer circumference of the right pole shoe.

The left pole piece, the permanent magnet, and the right pole piece are arranged in sequence to form a sealing assembly, and the sealing assembly is pushed into the casing.

The joint surface of the end cover and the shell is coated with sealant, and the end cover is fixed on the shell through screw connection with the thread on the shell.

The base mandrel assembly is pushed into the inner hole of the sealing assembly, the base and the shell are concave-convex matched, and the sealing gasket is fixedly connected by bolts and nuts therebetween.

The nitrogen cylinder of the gas input and pressure detection device is connected with the joint connected to the end cap through the pipeline.

A valve is installed on the pipeline, and a pressure gauge is installed between the valve and the joint.

The beneficial effects that the present invention has:

The device can detect the leakage of the shell of the large-diameter magnetic liquid sealing device, and eliminates the influence of the leakage of the shell on the large-diameter magnetic liquid sealing device.

Description of drawings

Fig. 1 is a structural diagram of a leak detection device for a large-diameter magnetic liquid rotary seal housing.

In the figure: base 1, shell 2, left pole shoe 3, permanent magnet 4, right pole shoe 5, screw 6, joint 7, pressure gauge 8, valve 9, end cover 10, second rubber sealing ring 11, mandrel 12 , Gasket 13, first rubber sealing ring 14.

Detailed ways

The present invention will be further described with accompanying drawing as specific embodiment:

A leak detection device for a large-diameter magnetic liquid rotary sealed casing, as shown in Figure 1, the connection between the various parts that constitute the device:

The base 1 is a flat cap structure, the mandrel 12 is a cylinder, and its open end is welded to the center of the inner wall of the base 1, and the mandrel 12 is coaxial with the base 1 to form a base mandrel assembly.

The shell 2 is a split structure, and the two petals are connected and fixed by bolts, and sealant is applied on the joint surface of the two petals to form the shell 2 .

Insert the first rubber sealing ring 14 into the concave groove on the outer circumference of the left pole shoe 3 , and insert the second rubber sealing ring 11 into the concave groove on the outer circumference of the right pole shoe 5 .

The left pole piece 3 , the permanent magnet 4 , and the right pole piece 5 are arranged in sequence to form a sealing assembly, and the sealing assembly is pushed into the casing 2 .

The joint surface of the end cover 10 and the shell 2 is coated with sealant, and the screw 6 is connected with the thread on the shell 2 to fix the end cover 10 on the shell 2;

The base mandrel assembly is pushed into the inner hole of the sealing assembly, the base 1 and the shell 2 are concave-convexly matched, and a sealing gasket 13 is fixedly connected by bolts and nuts therebetween.

The nitrogen cylinder of the gas input and pressure detection device is connected to the joint 7 connected to the end cap 10 through a pipeline.

A valve 9 is installed on the pipeline, and a pressure gauge 8 is installed between the valve 9 and the joint 7 .

The material of the left pole shoe 3 and the right pole shoe 5 is pure electric iron for use.

The shell 2, the end cover 10 and the screw 6 are all made of non-magnetic materials such as stainless steel.

The sealant used for each joint surface is 1596 sealant.

The gap between the outer circle of the mandrel 12 and the tooth tops of the left and right pole shoes is 0.02mm-0.03mm.

The working process of the leak detection device of the large diameter magnetic liquid rotary sealing shell:

First disconnect the connection between the pipeline and the joint 7, fill the device with a small amount of helium, then connect the pipeline, open the valve 9, fill the device with nitrogen, close the valve 9, and observe whether the pressure gauge drops , a drop indicates that there is a leak; at the same time, use a helium mass spectrometer leak detector to detect whether there is any leakage on the joint surfaces of the shell 2.

Claims (1)

1. major diameter magnetic liquid rotary seal shell leakage detection apparatus is characterized in that:

The base (1) that is connected to that constitutes between the each several part of this device is a flat-top cap structure, and axle (12) is a tubular, and its openend is welded in base (1) inwall center, and axle (12) is coaxial with base (1), constitutes the base arbor assembly;

Shell (2) is the split-type structure, with bolt two lobes is connected and fixes, and on the composition surface of two lobes, be coated with fluid sealant, constitutes shell (2);

First rubber seal (14) is embedded in the Baltimore groove on left pole shoe (3) excircle, second rubber seal (11) is embedded in the Baltimore groove on right pole shoe (5) excircle;

Described left pole shoe (3), permanent magnet (4), described right pole shoe (5) are arranged in order the composition seal assembly, and seal assembly is pushed in the shell (2);

Be coated with fluid sealant on the composition surface of end cap (10) and shell (2),, end cap (10) be fixed on the shell (2) through being threaded on screw (6) and the shell (2);

The base arbor assembly is pushed in the endoporus of seal assembly, base (1) and concavo-convex cooperation of shell (2) are established sealing gasket (13) therebetween and are fixedly connected through bolt and nut;

The nitrogen cylinder of gas input and pressure-detecting device is connected with joint (7) on being connected end cap (10) through pipeline;

Mounted valve on the described pipeline (9), setting pressure table (8) between valve (9) and joint (7).

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