JPS6143099B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a rotor is comprised of a hammer section and an impeller disposed on a crusher shaft, and the hammer arm of the hammer section is mounted on a hub ring of the crusher shaft. Relating to a ventilated hammer crusher or beater crusher used for grinding and drying, the crusher shaft being fixed in between and having a water cooling system in its longitudinal shaft. .

This type of crusher sucks high-temperature combustion gas from the combustion chamber of the boiler through a suction vent in order to dry the wet material to be crushed. Therefore, the rotor is exposed to high temperature loads during the grinding and drying process or when the hot combustion gases reach or exit the crusher.

It is known to cool crusher shafts via internal holes. In addition, the crusher shaft can be surrounded by a shaft protection tube in the area of the inlet cross section of the crusher,
In this case, cooling air can be introduced through the gap between the shaft protection tube and the crusher shaft.

In conventionally known ventilated hammer crushers in which the crusher shaft is not provided with an internal hole for water cooling, the cooling air introduced through the gap between the shaft protection tube and the clutch shaft is further supplied to the rotor. is guided through cooling channels between the hub and shaft of the In conventional ventilated hammer crushers, a relatively large amount of cooling air must be introduced through the cooling channels to sufficiently cool the crusher shaft. Nevertheless, the crusher shaft heats up to a relatively high temperature, so a crusher shaft that is cooled in this way is a compressor shaft that is cooled with water through holes provided inside. It will be inferior to

It is therefore a principal object of the present invention to develop the clutch of a ventilated hammer crusher of the type mentioned above in such a way as to avoid high temperatures on the bulging circumferential surface of the shaft and to reduce temperature differences across the shaft cross section. The purpose is to protect the shear shaft.

The present invention achieves the above object by making the bulging peripheral surface of the shaft of the hub ring surrounded by an outer sheath at a distance, and by providing a punched hole in the outer sheath through which a hammer arm is inserted. be. The still air in the gap between the jacket and the shaft bulge of the hub ring provides insulation. In addition, the void can be filled with an insulating material having suitable heat resistance, for example made of asbestos. A gaseous coolant can be introduced through the gap. In the manner described above, the crusher shaft can be protected from very high temperature loads in conjunction with effective internal cooling. The heat passing through the insulation layer in the cavity and the shaft body is removed by water in the holes provided inside, thus ensuring complete insulation effect and internal cooling.

The jacket can be disposed axially therethrough. In this case, the width of the perforation is greater than the width of the hammer arm by the maximum amount of axial expansion that occurs in the jacket relative to the crusher shaft.

Furthermore, the width of the outer jacket is determined by the width of the first hammer arm row on the crusher inlet side (as viewed from the crusher inlet in the flow direction of the material to be crushed) among the crusher shaft portions in which multiple rows of hammer arms are arranged. It is proposed that the width be limited to only encircle the crusher shaft portion with the first row of hammer arms). In this case, the cooling effect is lower than in the previously mentioned device, but the removal of the hammer arm is simpler.

According to another advantageous embodiment of the invention,
The jacket consists of a single ring, the width of the single ring being slightly greater than the spacing between two adjacent rows of hammer arms, and the rings overlapping in the area through which the hammer arms pass. It is proposed to do so. The ring is U
It can also be made in the shape of a letter, in which case the vertical web of the ring is inserted into a gap between the hammer arm and the hub ring.

By constructing the jacket from a single ring, it is possible to easily insert the hammer arm through the jacket. In this case, the installation and removal of the hammer arm is not impaired. Additionally, thermal expansion can be controlled so that stress does not appear on the envelope.

According to a constructional aspect of the invention which is particularly advantageous for attaching and detaching the hammer arm and the ring, the vertical web of the U-shaped ring extends close to the base of the gear, so that the hub bolt supporting the hammer arm can be attached to the hub bolt. is penetrated into said web.

If hot combustion gases are to be prevented as completely as possible from entering the shaft bulge surface of the hub ring, according to another advantageous embodiment of the invention, two adjacent U-shaped It has been proposed to cover the space between the ring and two adjacent hammer arms located in a row of hammer arms by a steel plate connected to the ring and the hammer arms.

A source of cooling gas can be connected to the annular gap between the shaft bulge of the hub ring and the envelope formed by the ring for supplying gaseous coolant into the gap. Alternatively, an axial blower can be mounted on the crusher shaft outside the crusher body, in which case the outlet cross section of the axial blower is connected to the air gap between the jacket and the hub ring. The vertical web of the U-shaped ring is thus provided with a recess in a high region above the hub ring in order to guide the cooling gas further.

A cooling gas can be connected to the gap for transporting gaseous coolant into the gap between the shaft bulge of the hub ring and the jacket. Alternatively, an axial blower can be mounted on the crusher shaft outside the crusher body, in which case the outlet cross section of the axial blower is connected to the air gap between the jacket and the hub ring.

If the hammer arm leg is adapted to fill the space between the two hub rings, the space between the two hub rings can be protected as completely as possible from hot combustion gases, in which case the two hammer The circumferential spacing between the arm legs is at most the axial spacing between two hub rings.
This is equivalent to 0.3 times the value. With this arrangement, collisions of the shaft hub with hot gases in the area of the hammer arm can be largely avoided. Additionally, the possibility of dust accumulation between the hammer arm legs can be reduced.

The invention will now be described in detail with reference to the accompanying drawings, in which embodiments of the invention are illustrated.

A ventilated hammer crusher (also referred to as a ventilated beater mill) according to the present invention includes a rotor disposed within a housing 1 thereof. The rotor includes a crusher shaft 2, which is rotatably driven by a motor 3 via a reduction gear, and bearings 4, 5 disposed outside the crusher housing 1. It is supported by a shaft. A hammer section 6 with a plurality of hammer arms 7 (which may also be called beater arms) and a hammer head 8 fixed to the hammer arms 7 and an impeller 9 with radial vanes 10 are connected to the crusher shaft 2. is attached to.

The impeller 9 working as a ventilation device is connected to the suction ventilation tube 1
2, the hot combustion gas coming from the combustion chamber of the boiler (not shown) is sucked in. In the case shown,
The material to be crushed, which is raw brown coal, enters the suction ventilator 12 and reaches the crusher through the crusher inlet 11 together with the high temperature combustion gas.
The pulverized material to be pulverized is fed to a boiler burner (not shown) through the passage section 13 of the feeding conduit.

As shown in FIG. 1, the hammer section 6 does not extend into the area of the crusher inlet 11, and the crusher shaft 2 is surrounded by a fixed shaft protection tube 14 in the area of the hammer section. It is.

The inside of the crusher shaft 2 is cooled using water, and for water cooling, a center hole 15 is provided, and a pipe 16 with a small diameter is inserted through the center hole 15. There is. The pipe 16 is connected to a cooling water supply pipe 17 located outside the crusher housing 1, while the annular flow path formed between the pipe 16 and the wall of the hole 15 is connected to a cooling water supply pipe 17 disposed outside the crusher housing 1. It is connected to the water reflux pipe 18.

There are multiple recesses 19 in the crusher shaft body.
is turned, thereby forming a plurality of hub rings 20
is formed. Hammer arms 7 are inserted into recesses 19 between these hub rings 20, respectively. The hammer arm 7 is supported by hub bolts 21 inserted into holes provided in the hub ring 20 and the hammer arm leg portion 22, respectively. The hub bolts 21 are secured using safety discs 23 attached to the first and last hub rings 20.

The shaft bulging peripheral surface 24 of the hub ring is surrounded by a jacket 25 with a required spacing therebetween. This interval is determined by welding to the inside of the outer sheath 25 and the shaft bulging peripheral surface 2 of the hub ring 20.
A suitable distance piece 26 supported on 4
(spacer). Outer cover 25
rotates integrally with the rotor.

The jacket 25 is provided with a perforation 27 through which the hammer arm 7 is inserted. The width of the punching hole 27 is larger than the width of the hammer arm 7 by the maximum amount of expansion in the axial direction that occurs in the jacket 25 depending on the temperature with respect to the crusher shaft 2 as a reference. The outer cover 25 is made of a cylindrical steel plate, and the steel plate has the following shapes:
Welding is done along the butted edges. The jacket 25 can also be made from two half-discs connected to each other using overlapping flat plates along abutted edges.

In the example illustrated in FIG.
5 covers the entire hammer section 6. However, it is also possible to limit the jacket 25 to the front part of the hammer section 6, which is exposed to high temperatures, and to extend only as far as the first row of hammer arms.

Still air exists in the gap 28 between the shaft bulging peripheral surface 24 and the outer sheath 25 of the hub ring 20, and due to its heat insulating effect, the still air causes the shaft bulging peripheral surface 24 to be heated to a high temperature due to combustion gas. It works to protect from loads. To increase the insulation effect, the void 28 can also be filled with an insulating material such as Masbest. Furthermore, a heat reflective layer made of, for example, an aluminum plate may be attached to the shaft bulging peripheral surface 24.

A gaseous coolant can be introduced between the jacket 25 and the hub ring 20 through the gap 28 .
This coolant may be air at room temperature. Air is drawn in from outside the ventilated hammer crusher through the free space between the crusher shaft 2 and the shaft protection tube 14 and flows into the annular chamber 29;
From the annular chamber 29 flows through the cavity 28. A special cooling gas source with suitable gas pressure is added to the annular chamber 29.
can be connected to. For this purpose, a cooling gas introduction tube 30 is connected to the casing part of the annular chamber 29.

Another method of supplying cooling air to the air gap 28 is to use an axial blower on the shaft journal between the crusher inlet outside the crusher housing 1 and the bearing 5, which is designed as a removable bearing. There is a way to set it up. This axial blower consists of an impeller 31 that rotates integrally with the crusher shaft 2. If necessary, a guide wheel 32 fixed to the crusher shaft 2 is attached to the rear of the impeller 31. will be placed. Impeller 3
1 is connected to the crusher housing 1;
It is adapted to rotate within a blower casing 33 having an inlet section. The outlet cross section of the axial blower opens into the free space between the crusher shaft 2 and the shaft protection tube 14.

The outer cover 25 has a perforation hole 2 through which the hammer arm 7 passes.
7 has to be provided, so that even though the hammer section is shielded, the hot combustion gases can pass through the jacket 25 into the recess 19 between the hub rings 20 and around the recess 19. heating or dust accumulation may occur.
In order to eliminate this risk as much as possible, the leg 22 of the hammer arm is made large enough so that it fills the gap 19 between the two hub rings 20 as completely as possible. Third
In the embodiment shown in the figures, two adjacent hammer arm legs 2 of the hammer arm row
The circumferential spacing between the two hub rings 20
0.3 of the mutual axial distance or width of the gap 19
It is set shorter than the double value.

In the embodiment shown in FIG. 4, the jacket consists of single rings 34, 35.
These rings 34, 35 are attached to the hammer arm 7.
A side recess 36 is provided along the edge for passage of the water. The rings 34, 35 are made slightly wider than the spacing between the hammer arms 7, so that they overlap in the area through which the hammer arms 7 pass. The second rings 34 are each
It is supported on the shaft bulging peripheral surface 24 of the hub ring 20. A ring 35 sandwiched between the rings 34 is removably connected to the rings 34 using, for example, a bolt. In this arrangement, the hammer arm 7 can be replaced by removing the individual rings 34, 35.

Although the temperature of the combustion gases always decreases when they pass through the ventilated hammer crusher, it is recommended to protect the crusher shaft 2 also at the rear of the ventilated hammer crusher. For this reason, the crusher shaft 2 has a cylindrical jacket 38 between the hammer section 6 and the deflector plate 37 of the impeller 9.
surrounded by. This jacket 38 is a continuation of the jacket 25 and covers the rear part of the hammer section 6 as well as the deflector 37 of the impeller 9.
It is supported by a square head member 39 attached to the side surface of. A belly plate 40, which is welded to the jacket 38 and rests on the crusher shaft 2, serves additionally to maintain the distance between the jacket 38 and the crusher shaft. The cooling gas introduced through the gap 28 can further be led into the space between the jacket 38 and the crusher shaft 2. As described for the jacket 25 surrounding the hammer section 6, here too the crusher shaft 2 and the jacket 38
A heat insulating effect can be secured by the heat insulating effect due to the stationary air existing between the two, the heat insulating effect due to the heat insulating material inserted, or a combination of the above measures.

The ring 41 forming the jacket shown in FIGS. 5 to 7 has a U-shaped design. The ring 41 consists of a member extending in the length direction of the crusher shaft 2 with a width approximately equal to the spacing between the hammer arms 7 of two adjacent rows, and a web 42 extending perpendicularly to the shaft. is welded to. This web 42 is inserted into a recess or gap 19 between the hammer arm 7 and the hub ring 20.
The web 42 extends almost to the bottom of the gap 19 and is provided with a hole 43 in its lower part. A hub bolt 21 for fixing the hammer arm 7 is inserted through the hole 43.
The U-shaped ring 41 can be attached to and removed from the hammer arm 7 using the fixing procedure described above.

The space that remains open between two adjacent U-shaped rings 41 and two adjacent hammer arms 7 in the hammer arm row is formed by a steel plate 44.
covered by. This steel plate 44 is connected to the U-shaped ring 41 by line welding. The side abutment 45 of the steel plate 44 is fitted into a catch 46 welded to the hammer arm 7.
The web 42 of the U-shaped ring 41 is recessed 47 in the upper part of the shaft bulging peripheral surface 24 of the hub ring 20.
The recess 47 thus serves to guide a cooling gas, such as air, through the gap 28 between the shaft bulges 24 of the hub ring 20.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a ventilation hammer crusher according to the present invention cut in the length direction, and FIG. 2 is a cross-sectional view showing the hammer section of the ventilation hammer crusher cut in the length direction. 3 is a sectional view taken along the line -- of FIG. 2; FIG. 4 is a longitudinal sectional view of another embodiment of the hammer section; and FIG. 5 is a further sectional view of the hammer section. 6 is a sectional view along the line -- of FIG. 5, and FIG. 7 is an enlarged detailed view of section Z of FIG. 5; 1 is a crusher housing, 2 is a crusher shaft, 3 is a motor, 4 and 5 are bearings, 6 is a hammer section, 7 is a hammer arm, 8 is a hammer head, 9 is an impeller, 10 is a blade, 11 1 is a crusher inlet, 12 is a suction ventilator, 13 is a passage, 14 is a shaft protection pipe, 1
5 is a center hole, 16 is a cooling water pipe, 17 is a cooling water supply pipe, 18 is a cooling water return pipe, 19 is a recess,
20 is a hub ring, 21 is a hub bolt, 22 is a hammer arm leg, 23 is a safety disk, 24 is a shaft bulging peripheral surface, 25 is an outer cover, 26 is a distance piece, 29 is a punched hole, 28 is a gap, 29 is an annular chamber, 30 is a tube for introducing cooling gas, 31 is an impeller, 32 is a guide wheel, 34 and 35 are single rings, 36 is a side recess, 37 is a deflection plate, 38 is an outer cover, 39 is a square head members, 40 is a belly plate;
41 is a ring, 42 is a web, 43 is a hole, 44 is a steel plate, 45 is a side stopper, 46 is a stopper, and 47 is a recess.

Claims (1)

[Claims] 1. The rotor comprises a hammer section attached to a crusher shaft and an impeller, and the hammer arm of the hammer section is fixed between a hub ring of the crusher shaft, In the case where the crusher shaft is equipped with a water cooling system in its longitudinal axis, the shaft bulging peripheral surface 24 of the hub ring 20
are surrounded by a jacket 25 at a distance, and the jacket 25 is provided with a punching hole 27 through which the hammer arm 7 is inserted. 2. The ventilation hammer clamp according to claim 1, wherein the gap 28 formed between the outer sheath 25 and the shaft bulging peripheral surface 24 of the hub ring 20 is filled with a heat insulating material. Tushiya. 3. The ventilated hammer clamp according to claim 1, characterized in that a gaseous coolant flows through the gap 28 formed between the outer sheath 25 and the shaft bulging peripheral surface 24 of the hub ring 20. Tushiya. 4 The shaft bulging peripheral surface 24 of the hub ring 20 is
A ventilation hammer crusher according to any one of claims 1 to 3, characterized in that it is provided with a coating that reflects heat. 5 The outer sheath 25 is disposed to penetrate in the axial direction, and the width of the punched hole 27 is the same as that of the crusher shaft 2.
The width of the hammer arm 7 is greater than the width of the hammer arm 7 by the maximum amount of expansion in the axial direction that occurs in the jacket 25 based on the width of the hammer arm 7.
Ventilation hammer crusher as described in section. 6. The width of the outer cover 25 is such that it surrounds only the crusher shaft portion having the first hammer arm row on the crusher inlet 11 side among the crusher shaft portions in which multiple rows of hammer arms are arranged. Any one of claims 1 to 5, characterized in that the scope of the claim is limited to the breadth of
Ventilation hammer crusher as described in section. 7. Claim 1, characterized in that the jacket consists of a single ring 34, 35, 41, the width of which is equal to the spacing between two adjacent rows of hammer arms 7. The ventilation hammer crusher according to any one of items 1 to 4. 8. The width of the single rings 34, 35, 41 is slightly larger than the spacing between two adjacent rows of hammer arms 7;
8. A ventilated hammer crusher according to claim 7, wherein the hammer arms overlap in the region through which the hammer arm 7 is inserted. 9. The ring 41 is U-shaped and the vertical web 42 of the ring 41 is inserted into the gap 19 between the hammer arm 7 and the hub ring 20. A ventilation hammer crusher according to claim 7. 10 The space between two adjacent U-shaped rings 41 and two adjacent hammer arms 7 located in the hammer arm row is covered by a steel plate 44 connected to the rings 41 and the hammer arms 7. Claim 7 characterized in that
The ventilation hammer crusher according to item 1 or item 9. 11 The vertical web 42 of the U-shaped ring 41 is
A hub bolt 21 extends near the base of the gear 19 and supports the hammer arm 7.
is penetrated into the web 42. Claim 7, 9, or 10
Ventilation hammer crusher as described in section. 12 The vertical web 42 of the U-shaped ring 41 is
Claim 7, characterized in that a recess 47 is provided in an area higher than the hub ring 20.
The ventilation hammer crusher according to item 9, 10 or 11. 13. Claim 1, characterized in that a cooling gas source is connected to the gap 28 between the single rings 34, 35, 41 of the outer cover and the hub ring 20.
The ventilation hammer crusher according to item 1 or any one of items 3 to 12. 14. An axial blower is attached to the crusher shaft 2 on the outside of the crusher body 1, and the outlet cross section of the axial blower is connected to the air gap 28 between the jacket and the hub ring 20. A ventilation hammer crusher according to any one of claims 1 or 3 to 12. 15 The hammer arm legs 22 fill the space between the two hub rings 20, and the circumferential spacing between two adjacent hammer arm legs 22 is at most the distance between the two hub rings 20. A ventilation hammer crusher according to any one of claims 1 to 14, characterized in that the distance is equal to 0.3 times the axial spacing. 16 The part of the crusher shaft 2 between the hammer section 6 and the impeller 9 is likewise surrounded by a sheath 38, which is supported on the hammer section 6 and the impeller 9. The ventilation hammer crusher according to any one of claims 1 to 15, characterized in that: