JPH0727321A - Cooling type screw feeder - Google Patents

Abstract

PURPOSE:To enable a requisite heat transfer efficiency to be assured without increasing an amount of cooling water even if an amount of substance being transferred is increased and under saving of the amount of cooling water in a cooling type screw feeder for use in transferring and cooling ashes or the like generated from a coal burning boiler. CONSTITUTION:A helical screw 2 is arranged around a screw shaft 1 and the shaft is rotated in a screw jacket so as to transfer substance. The shaft 1 has a longitudinal hollow, on the axis of which an inner cylinder 3 is arranged to keeping a space between it and the inner surface of the shaft 1. Cooling water is supplied from an inlet 30, passes through the space between the inner cylinder 3 and the shaft 1 to release heat from the substance being transferred and then the cooling water flows out. As the amount of substance is increased, the diameter of the shaft 1 is made large. Even if the diameter is made large, the diameter of the inner cylinder 3 is properly set, thereby an amount of cooling water and water speed can be set to the suitable values.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling type screw feeder used for transferring and cooling ash, etc. generated from a coal-fired boiler.

[0002]

2. Description of the Related Art A conventional cooling type screw feeder is shown in FIG.
And the jacket 1 as shown in FIG.
1, a screw shaft 13, and a screw 12 fixed to the screw shaft 13.
The transferred material entering from the transferred material inlet 20 is passed between the jacket 11 and the screw shaft 13 by the screw shaft 13
Is transported by the screw 12 in accordance with the rotation of, and is cooled during that time and discharged from the outlet 21.

The inside of the jacket 11 is hollow 14 as shown in FIG. 6, and cooling water is supplied from an inlet 16 and discharged from an outlet 17. On the other hand, the inside of the screw shaft 13 is also a simple cavity 15, and cooling water is supplied from the inlet 18 and discharged from the outlet 19.

[0004]

SUMMARY OF THE INVENTION In the conventional structure,
In order to enhance the cooling effect, the diameter of the shaft is increased in order to increase the heat exchange from the screw shaft 11, and the surface area of the screw shaft 11, that is, the heat transfer area is increased. However, in order not to impair the heat transfer efficiency, the screw is used. There is a problem that it is necessary to secure the cooling water velocity in the shaft 11, and if the diameter of the screw shaft 11 is increased to increase the heat transfer area, the cooling water amount must be increased in proportion to its square. is there.

The present invention has been made for the purpose of improving the heat transfer efficiency by reducing the internal structure of the screw shaft 11, reducing the amount of cooling water, and downsizing the apparatus.

[0006]

As a first means for solving the above-mentioned problems, the present invention provides an inner cylinder in a passage for cooling water in a screw shaft and arbitrarily selects an outer diameter dimension thereof. Thus, the structure of the screw shaft is such that the amount of cooling water flowing in the space between the screw shaft and the inner cylinder and the cooling water velocity can be selected to arbitrary values.

As a second means, an inner cylinder having an inner screw attached is provided in a cooling water passage in a screw shaft so that an amount of cooling water and a cooling water speed can be arbitrarily selected and the cooling water is swirled. And the stirring motion is applied to increase the contact between the cooling water and the screw shaft surface, that is, the heat transfer surface.

As the third means, guide blades are provided instead of the inner screw in order to obtain the same operation and effect as the operation and effect of the second means.

That is, according to the first aspect of the present invention, the screw shaft having a spiral screw is rotated in the screw jacket, and the cooling water is flown through the cooling water passage provided in the screw shaft to transfer the transfer object. In a cooling type screw feeder that cools together with the cooling shaft, an inner cylinder is provided so as to have a space around the cooling water passage in the screw shaft, and cooling water flows through the space between the inner cylinder and the screw shaft. The present invention provides a cooling type screw feeder characterized by being configured.

Further, according to the second aspect of the invention, the screw shaft having the spiral screw is rotated in the screw jacket, and the cooling water is flown through the cooling water passage provided in the screw shaft to transfer the transfer object. In a cooling type screw feeder for cooling together with an inner cylinder arranged so as to have a space around the cooling water passage in the screw shaft, and an inner spirally provided on the surface of the inner cylinder in the space. A cooling type screw feeder characterized by comprising a screw and giving swirling and stirring to the cooling water.

Further, according to a third aspect of the invention, a screw shaft having a spiral screw is rotated in a screw jacket, and cooling water is caused to flow through a cooling water passage provided in the screw shaft to transfer an object to be transferred. In the cooling type screw feeder that cools together with the cooling water, an inner cylinder arranged so as to have a space around the cooling water passage in the screw shaft, and a guide blade provided on the surface of the inner cylinder in the space. The present invention provides a cooling type screw feeder characterized by comprising swirling and stirring the cooling water.

[0012]

Since the present invention is the means as described above, in the invention of claim 1, the diameter of the screw shaft is increased in the case of the feeder in which the processing capacity of the transferred material is increased, but the diameter of the shaft is increased. However, by arbitrarily selecting the dimensions of the inner cylinder, the cooling water velocity flowing in the space inside the screw shaft can be selected to have the highest heat transfer efficiency, and the cooling water amount can also be minimized.

According to the invention of claim 2, in addition to the operation of claim 1, the cooling water swirls and agitates by the inner screw, so that the contact between the heat transfer surface and the cooling water is prevented. Stirring is increased, and heat transfer efficiency is further increased.

Further, in the invention of claim 3, the guide blades provided in place of the inner screw of the invention of claim 2 are in contact with the heat transfer surface and the cooling water as in the inner screw of the invention of claim 2. And the cooling water is agitated to further improve the heat transfer efficiency.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 is a side view of a screw shaft and a screw of a cooling type screw feeder according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line AA. The screw shaft 1 of the first embodiment shown in FIG. 1 is arranged in a screw jacket 11 provided with a transfer material inlet 20 and an outlet 21, a cooling water inlet 16 and an outlet 17 of the conventional example shown in FIG. And, it relates to the improvement of the screw shaft. Therefore, in FIG. 1, the screw jacket is omitted and only the screw shaft and the structural portion of the screw are shown.

In both figures, 1 is a screw shaft,
Reference numeral 2 is a screw spirally provided on the outer periphery of the shaft 1, and 3 is a feature of the present invention. The inner cylinder is newly provided, and the support plate 5 is provided so as to be located substantially in the center of the internal cavity of the screw shaft 1. It is supported by two places. The cooling water in the screw shaft 1 enters from the cooling water inlet 32, flows in the space 4 formed by the screw shaft 1 and the inner cylinder 3, and removes heat from the transferred material, thereby cooling water outlet 33.
More outflow. In the side view of FIG. 1, the inner cylinder 3 is shown by hatching for clarity.

The inner cylinder 3 is a solid one which is attached to the screw shaft 1 by a support plate 5 as shown in the section AA of FIG. Also, by increasing the outer diameter of the inner cylinder 3, the cross-sectional area of the space 4 is reduced, and the cooling water speed can be increased. On the other hand, conversely, if the outer diameter of the inner cylinder 3 is reduced, the cross-sectional area of the space 4 can be increased and the amount of cooling water can be increased. It can be set to an appropriate amount.
The cooling water is supplied to the inside of the screw shaft 1 through the inlet 30 at the end of the screw shaft 1, flows through the space 4, and is discharged through the outlet 31 at the other end.

As described above, in the screw feeder of the first embodiment, the inner cylinder 3 is provided substantially in the center of the cavity inside the screw shaft 1, and the space 4 formed by the inner cylinder 3 and the inside of the shaft 1 is formed. By providing the structure,
When the diameter of the screw shaft 1 is adjusted to be larger or smaller, and the diameter is made larger, the heat transfer surface area is increased, and the presence of the inner cylinder prevents the required amount of cooling water flowing through this space from increasing. The thermal efficiency can be obtained.

Further, no matter how the processing capacity of the transferred material changes, the cross-sectional area of the space 4, that is, the cross-sectional area of the cooling water passage can be arbitrarily selected by selecting the diameter of the inner cylinder 4, so that it is more than necessary. It is possible to obtain the necessary heat transfer efficiency without flowing cooling water to the cooling water, which saves the cooling water.

FIG. 3 is a side view of the screw shaft and screw of the cooling type screw feeder according to the second embodiment of the present invention, and FIG. 4 is a sectional view taken along line BB thereof. Like the first embodiment, this second embodiment also relates to the screw shaft, the screw jacket is omitted, and only the screw shaft and the structural portion of the screw are shown.

In both figures, 9 is a screw shaft,
6 is a screw spirally provided on the outer periphery of the shaft, 7 is an inner cylinder arranged substantially in the center of the screw shaft 9, 8 is an inner screw, which is fixed around the inner cylinder 7 and It is provided in a spiral shape with the inner peripheral surface of the cavity. Cooling water is screw shaft 9
It is supplied from the cooling water inlet 32 at one end of the cooling water inlet 32, flows through the space between the screw shaft 9 and the inner cylinder 7 while swirling by the inner screw 8, removes heat from the transferred material, and flows out from the cooling water outlet 33. As in FIG. 1, the inner cylinder 7 is also shown in FIG.
Are shaded for clarity.

In the screw feeder of the second embodiment as described above, an inner cylinder 7 is provided substantially at the center of the cavity inside the screw shaft 1, and a spiral shape is formed between the inner cylinder 7 and the cavity inside the screw shaft 1. Even if the diameter of the screw shaft is increased and the heat transfer area is increased by providing the structure in which the inner screw 8 is provided, the presence of the inner cylinder 7 does not increase the amount of cooling water. Since the cooling water is swirled while being swirled, the required heat transfer efficiency can be obtained. Further, as compared with the first embodiment, the flow passage of the cooling water is swirled by the action of the inner screw 8 which is a feature of the present embodiment, so that the cooling water is agitated and the contact with the cooling water is substantially increased. The heat transfer efficiency is improved.

Further, no matter how the processing capacity of the transferred material changes, the cross-sectional area of the cooling water passage can be arbitrarily selected by selecting the diameter of the inner cylinder 4, so that it is necessary without flowing cooling water more than necessary. It is possible to obtain high heat transfer efficiency and save cooling water.

As a third embodiment, although not shown, the inner cylinder 7 is used instead of the inner screw 8 of the second embodiment.
Guide vanes are provided at one position in the axial longitudinal direction between the screw shaft 9 and the inner surface space of the screw shaft 9 or at several places as required, and the guide vanes swirl the cooling water and stir the cooling water to flow it. An example is also proposed in which the same effect as the inner screw 8 of the second embodiment is achieved. This guide vane may be any structure that gives a swirling flow to the cooling water and stirs it.
It suffices that several blades are provided on this surface centering on the inner cylinder and the cooling water is swirled and flowed.

Regarding the operation and effect of this third embodiment,
Compared with the above-mentioned second embodiment, the inner screw 8 acts in the same manner in place of the guide vanes, and therefore its explanation is omitted.

[0026]

As described above in detail, in the present invention, the inner cylinder is provided inside the screw shaft,
Further, since the cooling water passage is formed by combining the inner cylinder and the inner screw, the following effects are obtained.

No matter how the processing capacity of the transferred material changes,
Since the cross-sectional area of the cooling water passage can be arbitrarily selected by selecting the diameter of the inner cylinder, the required heat transfer efficiency can be obtained without flowing the cooling water more than necessary, and the cooling water can be saved. Further, by providing an inner screw or guide vanes, a swirling flow and agitation are given to the cooling water, so that the heat transfer efficiency is further enhanced.

Further, since the heat transfer efficiency is improved, the heat transfer area can be reduced, and the device can be downsized accordingly.

[Brief description of drawings]

FIG. 1 is a side view of a cooling type screw feeder according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a side view of a cooling type screw feeder according to a second embodiment of the present invention.

4 is a sectional view taken along line BB in FIG.

FIG. 5 is a side view of a conventional cooling type screw feeder.

6 is a cross-sectional view taken along line CC of FIG.

[Explanation of symbols]

 1 Screw Shaft 2 Screw 3 Inner Cylinder 4 Space 5 Support Plate 6 Screw 7 Inner Cylinder 8 Inner Screw 9 Screw Shaft 30 Cooling Water Inlet 31 Cooling Water Outlet 32 Cooling Water Inlet 33 Cooling Water Outlet

Claims (3)

[Claims] 1. A cooling type screw feeder for rotating a screw shaft having a spiral screw in a screw jacket, and flowing cooling water through a cooling water passage provided in the screw shaft to transfer an object and to cool it. The inner cylinder is provided so as to have a space around the cooling water passage in the screw shaft, and cooling water flows through the space between the inner cylinder and the screw shaft. Cooling screw feeder. 2. A cooling type screw feeder for rotating a screw shaft having a spiral screw in a screw jacket and flowing cooling water through a cooling water passage provided in the screw shaft to transfer a substance to be transported and to cool it. In the cooling water passage in the screw shaft, the inner cylinder arranged so as to have a space around, and an inner screw spirally provided on the surface of the inner cylinder in the space. A cooling type screw feeder characterized by giving swirling and stirring to the cooling water. 3. A cooling type screw feeder which rotates a screw shaft having a spiral screw in a screw jacket, and causes cooling water to flow through a cooling water passage provided in the screw shaft to transfer an object to be transported and to cool it. A cooling water passage in the screw shaft, the inner cylinder being arranged so as to have a space around it, and a guide vane provided on the surface of the inner cylinder in the space. A cooling type screw feeder characterized in that water is swirled and stirred.