JPS5931703Y2 - Carbon trap for vacuum carburizing furnace - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to an improvement of a carbon trap for a vacuum carburizing furnace.

As shown in FIG. 1, the conventional carbon trap has a cylindrical passage defined by water-cooled walls a and supported approximately horizontally. It is mainly composed of baffle plates C extending alternately.

These baffle plates C extend from the upper wall a1 of the passage facing the bottom wall a2, and include a lower notched baffle plate C0 that forms a predetermined gap between the upper wall a1 and the bottom wall a2, and a lower cutout baffle plate C0 that extends from the upper wall a1 of the passageway toward the bottom wall a2. and an upper and lower cut baffle plate C2 that extends toward the upper wall a1 and forms a predetermined gap between the upper wall a1 and the upper wall a1.

Further, one end opening of the cylindrical passage forms an exhaust gas inlet I, and the other end opening forms an exhaust gas outlet O.

In this carbon trap, the carburizing exhaust gas from the vacuum carburizing furnace flows in from the exhaust gas population I, and the lower notched baffle plate C1 and the upper lower notched baffle plate C2, which are vertically vertically arranged alternately from the water cooling wall a for cooling, and an upper lower notch baffle plate C2, The flow rate decreases through the gap, changing its direction upward and then downward.

During this time, carbon contained in the exhaust gas remains on the upstream and downstream sides of the upper lower cutting baffle C2, as shown in FIG.

In this way, since the flow rate and direction are changed by the baffle plates and the carbon particles are retained in the lower part, the effect of removing fine carbon powder is not sufficient unless a large number of baffle plates are installed.

The overall length of this type of carbon trap must be increased if the desired degree of removal is to be achieved.

Furthermore, since the trapping action on the carbon fine powder particle size in the trap is not necessarily constant, the particle size of the fine powder to be removed is not stable.

Since the trap is made of a one-piece structure, not only does it have to be removed in its entirety when cleaning it, but the longer the overall length of the baffle plate, the more difficult it is to remove the accumulated carbon. The downside is that it can be difficult.

The present invention has been devised to solve the drawbacks of conventional carbon traps as described above.

The purpose of this invention is to be able to completely capture and remove free carbon of a certain size or more in the exhaust gas discharged from a vacuum carburizing furnace, to downsize the overall structure, and to improve the cooling effect of the exhaust gas. Provided is a carbon trap for a vacuum furnace that can be improved.

In order to achieve the above objective, the flow of the exhaust gas exhausted from the vacuum carburizing furnace is temporarily reversed so that it collides with the cooling wall, and coarse carbon in the exhaust gas is removed along the cooling wall by inertial force. Next, they discovered that fine carbon particles could be removed by passing it through a filter, leading to the completion of the present invention.

An embodiment of the present invention will be described below with reference to FIG.

FIG. 2 shows a carbon trap for a vacuum carburizing furnace according to the present invention.

2 is an exhaust gas inlet connected to an exhaust gas passage of a vacuum carburizing furnace (not shown); 1 is a housing fixed to the lower side of the inlet 2 and formed by a cooling wall 3;

The cross-sectional area of the housing 1 is larger than that of the inlet 2;
Therefore, the inside of the housing 1 is larger than the introduction port 2.

The cooling wall 3 is formed by an inner cylinder wall 4, an outer cylinder wall 5, and an upper wall 6 and a bottom wall (flange) 7 fixed to these cylinder walls.

A refrigerant inlet 8 is provided at the lower part of the outer cylinder wall 5, and a refrigerant outlet 9 is provided at the upper part.

Reference numeral 10 denotes a bottom plate that partially partitions the inside of the housing 1 and the outside thereof, and is removably attached to the bottom wall flange 7 provided at the lower part of the water cooling wall 3 with mounting bolts 11.

A dispersion plate 12 of such a size as to block the carburizing exhaust gas flow from the inlet 2 is disposed within the above-mentioned housing 1 on the downstream side of the inlet 2.

This dispersion plate 12 is formed to be larger than the cross-sectional area of the introduction port 2 and smaller than the inner diameter of the inner cylinder wall 4.

A cylindrical filter 13 is provided on the peripheral edge of the dispersion plate 12 and extends along the inner cylindrical wall 4 of the cooling wall 3 at a predetermined gap S from the inner surface of the dispersion plate 12 .

This filter 13 includes a filter outer cylinder 14 hanging from the periphery of the dispersion plate 12, a filter inner cylinder 15 hanging from the center of the distribution plate 12, and a filter bottom plate (described later) that contacts the lower end of the filter inner cylinder 15. A housing 17 is formed which is partitioned by 16 and 16, and a filter element 18 is filled in this housing 17.

The filter outer tube 14, the filter inner tube 15, and the filter bottom plate 16 are provided with a large number of thin through holes.

An exhaust gas outlet 19 is formed at the bottom of this filter 13 .

As shown in the figure, this outlet 19 has a lower funnel-shaped cylindrical body 20 fixed in a through hole 21 formed in the bottom plate 10, and an upper portion of the cylindrical body 20 is provided with a filter so as to support the free end of the filter inner cylinder 15. A bottom plate 16 is fixed.

The filter 13 is supported on the filter bottom plate 16 as described above, and in this supported state, the free end of the filter outer cylinder 14 is removably attached to the upper part of the cylinder body with the mounting bolt 22.

In this way, the lower part of the housing 1 is partitioned into its interior and exterior so that carbon can be removed.

Further, a retention annular plate 23 is provided upright on the bottom plate 10 inside the inner cylinder wall 4 as required.

Next, the operation of the device of the present invention will be explained.

High temperature (approximately 150° C.) carburizing exhaust gas from the vacuum carburizing furnace enters the carbon trap through the exhaust gas inlet 2.

The exhaust gas hits the dispersion plate 12 and is scattered radially, and is cooled by exchanging heat with the cooling wall 3 while flowing down along the cooling wall 3 through which cooling water is passed.

As this flow progresses, the exhaust gas flows between the filter outer cylinder wall 14 and the cooling wall 3.

The exhaust gas gradually diverts its flow from downwards to sideways to the filter 13.

During this flow diversion, the carbon particles subjected to downward inertial force fall between the cooling wall 3 and the filter outer cylinder wall 14 and remain inside the retention annular plate 23.

That is, secondly, the coarse carbon particles are captured.

The exhaust gas that has been subsequently captured in this way is transferred to the filter 1.
It passes through a filter element 18 packed in 3.

At this time, carbon particles larger than a certain particle size determined by the filtering ability of the filter element 18 are secondarily captured, and the exhaust gas is completely filtered.

The filtered exhaust gas is exhausted from the exhaust gas outlet 19.

As the capture of carbon particles continues as described above,
If the amount of coarse particles retained exceeds the permissible limit, or if the filtration performance of the filter 13 decreases below the permissible limit,
Attach the bottom plate 10 with the filter 13 attached using the mounting bolts 11.
is removed, the connection with the bottom wall flange 7 is released, and the carbon trap is taken out of the carbon trap.

Then, the attachment pole I/22 is removed to uncouple the cylinder 20 and the filter outer cylinder 14, and the combination of the filter outer cylinder 14, filter inner cylinder 15, and dispersion plate 12 is removed from the cylinder 20.

Thereafter, the coarse carbon particles that have been retained between the retention annular plate 23 and the cylindrical body 20 are removed.

Also, the filter element 18 packed between the filter outer cylinder 14 and the filter inner cylinder 15 is replaced.

After this exchange, the combined body of the filter outer cylinder 14, the filter inner cylinder 15, and the dispersion plate 12 is placed on the cylinder body 20 in order to connect the combined body onto the cylinder body 20 forming the exhaust gas outlet 19,
While this is supported by the filter inner cylinder 15, the filter outer cylinder 14 and the cylindrical body 20 are connected using mounting bolts 22.

After the bottom plate 10 with the filter 13 attached thereto is aligned with the bottom wall flange 7 and the bottom plate 10 with the filter 13 inserted into the housing 1, they are connected and fixed with the mounting bolts 11.

Thereafter, the operation of the carbon trap is restarted.

By arranging the carbon traps described above in parallel as necessary, carbon can be continuously removed from the carburizing exhaust gas.

In summary, the present invention provides the following excellent effects.

(1) Carbon in the exhaust gas exhausted from the vacuum carburizing furnace can be completely removed, thereby preventing air pollution and the like.

(2) Furthermore, the entire device can be downsized and can be installed anywhere in the exhaust gas passage.

(3) By adopting a configuration in which the exhaust gas from the vacuum carburizing furnace collides with the cooling wall via the dispersion plate, the exhaust gas can be effectively cooled.

(4) The filter that secondarily removes carbon from the exhaust gas can be easily removed from the device, making maintenance easy.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a conventional carbon trap, and FIG. 2 is a longitudinal sectional view of the carbon trap of the present invention. In the figure, 1 is a housing, 2 is an inlet, 3 is a cooling wall, 12
13 is a dispersion plate, 13 is a filter, and 19 is an exhaust gas outlet.

Claims (1)

[Scope of utility model registration request] A device installed in the exhaust gas passage of a vacuum carburizing furnace to remove carbon from the exhaust gas, which includes a housing defined by a cooling wall, an exhaust gas inlet formed in the upper part of the housing, and a downstream side of the exhaust gas inlet. an exhaust gas dispersion plate disposed so as to block this; a cylindrical filter extending along the cooling wall at a predetermined interval by the exhaust gas dispersion plate; and an exhaust gas outlet provided at a lower part, the exhaust gas from the exhaust gas inlet is reversed from the exhaust gas distribution plate to the cooling wall, and inertia is applied to cause the carbon particles to fall and stay in the gap while the filter is being operated. A carbon trap for a vacuum carburizing furnace, characterized in that it is configured to allow carbon to pass through.