CN1040183C

CN1040183C - Percussive wheel pulverising machine

Info

Publication number: CN1040183C
Application number: CN95101936A
Authority: CN
Inventors: 蒂乌·勒·万; 约翰内斯·克雷策; 库尔特·艾德讷
Original assignee: Babcock Lentjes Kraftwerkstechnik GmbH
Current assignee: Babcock Lentjes Kraftwerkstechnik GmbH
Priority date: 1994-04-15
Filing date: 1995-02-10
Publication date: 1998-10-14
Anticipated expiration: 2015-02-10
Also published as: AU1492295A; DE4412924A1; GR1002373B; SI9500127A; YU5495A; RO115702B1; CN1124675A; AU683531B2

Abstract

Blades (9) are mounted between two discs (7,8) of the grinding wheel (4). The inward-facing edge of the blades (9) projects on a part of the width of the blade inwards into the inlet cross-section of the wheel (4). The projection (11) faces the inlet of the wheel (4) and has a width amounting to 1 to 40% of the width of the blade (9), preferably from 5 to 20%.

Description

Percussive wheel pulverising machine

The present invention relates to a kind of percussive wheel pulverising machine, this percussive wheel pulverising machine has one and is located in the grater housing and is fixed tightly in the beater wheel that grinds on the arbor, and this beater wheel has radially outlet and be provided with a plurality of blades between two disks of an axial inlet and.

(see (1990) 587 to 590 pages of 70 phases of VBG power plant technology) and resemble that the beater wheel of working the ventilating fan sucks the flue gas of heat in this grater from a combustion chamber, this flue gas is used for making the triturate drying will introducing when thing to be ground in the grater grinds.Be contained in the same hammer stem portion that grinds on the arbor if be provided with one in the front of beater wheel, flue gas and thing to be ground can mix mutually before arriving beater wheel within the specific limits so.And if there is not such hammer stem portion, as pure percussive wheel pulverising machine, flue gas and wait to grind thing and when entering beater wheel, can have harm pockety so.The then more impact that is subjected to waiting to grind thing of more other axial area bands of hot flue gas that runs into of some axial area band of beater wheel as a result.Other district's bands then bear erosion thereby certain some district's band can generate heat consumingly.Because this uneven load, beater wheel just can not be given full play to its effect at aspects such as the stability of the production capacity of grater, grater and robustnesses.

The objective of the invention is to make the load homogenising of the beater wheel of this class grater.

Above-mentioned purpose realizes by a kind of like this percussive wheel pulverising machine, it has one and is located in the grater housing and is fixed tightly in the beater wheel that grinds on the arbor, this beater wheel has radially outlet and be provided with a plurality of blades between two disks of an axial inlet and, wherein, on its partial width, establish a jut in the import cross-sectional area that protrudes inwardly into beater wheel on one side inwardly of at least one blade, described jut is located at the position near the import of beater wheel, and has a width that is equivalent to the 1-40% of width of blade.

The jut of blade makes this logistics produce eddy current when flue gas and logistics to be ground enter beater wheel.Thereby wait to grind thing and in flue gas stream and on the cross section of beater wheel outlet, be able to even distribution.Beater wheel bearing load equably just aspect temperature and erosion like this, thus beater wheel can optimally design, and can access prolongation the service life of grater.

One embodiment of the present of invention are drawn with accompanying drawing and will be described in detail below, and wherein Fig. 1 is the enlarged drawing of Z unit among Fig. 1 for the profilograph Fig. 2 by percussive wheel pulverising machine.

Percussive wheel pulverising machine shown in the figure uses hot flue gas to be used for grinding former brown coal as dry gas and carrying gas.Percussive wheel pulverising machine has import department 2 and export department 3 of a grater housing 1, a bell mouth shape.In the export department 3 also the fine coal pipe by unshowned guiding powdered coal burner on transition piece or sifter and the figure be connected.Have a beater wheel 4 to rotate in grater housing 1, this beater wheel is located at grinding on the arbor 5 of only at one end supporting, and this energy is driven by a motor 6.Be provided with one deck backplate on the inner face of the grater in the scope of beater wheel 4.

Beater wheel 4 have an axial import and one radially outlet and be to constitute by two disks that are provided with blade that interlink together and betwixt.Rear disk 8 is fixed tightly in to grind on the arbor 5 and by a baffle plate 10 that is placed on the front and protects.Preceding disk 7 is made annular, the hole of disk 7 becomes the axial inlet of beater wheel 4, it is to be made of the wear-resisting flat plate that is essentially that the import department 2 of grater housing 1 carries out steering blade 9 to this, and they are fixed tightly on the beater wheel 4 by the retainer on the

disk

7,8.

Wait to grind for example former brown coal of thing and be directed to grater by a vertical tube that is connected with the import department 2 of grater housing 1.Resemble the beater wheel 4 of working the ventilating fan simultaneously and suck hot flue gas from boiler furnace as dry gas and carrying gas, make and wait to grind thing and when grinding, dried by vertical tube.Waiting of introducing ground the import department 2 of thing by bell mouth shape and slided until run into till the rear portion of beater wheel.Wait to grind thing here and controlled and in the grater housing, constantly thrown to backplate by blade 9, until it is smashed to pieces and can be carried under one's arms by carrying gas and just come to an end by export department.By this beater wheel 4 with wait to grind impact between the thing, on the part of the close rear disk 8 of blade 9 because erosion will be subjected to more violent impact.There is more hot carrying gas deflection to contact simultaneously with the front portion of blade 9.Therefore beater wheel 4 is uneven in the distribution of the load aspect temperature and the erosion.In order to prevent to produce this shortcoming, blade 9 should be by following said method construct.

There is a part to protrude inwardly in the import cross-sectional area of beater wheel 4 on the inner edge parallel of blade 9 with grinding arbor 5.The jut 11 of Gou Chenging is located on the blade 9 on the part near the import of beater wheel 4 or annular disk 7 like this.Jut 11 can be made on blade or add afterwards with welding method.The width of jut 11 be about blade 9 width 1～40%, be preferably in the scope of 5～20% width and select for use.The height of jut 11 is 0.1～1 times of blade 9 total heights.The side of jut 11 can with grind arbor 5 vertical or with vertical line at angle.Jut 11 can adopt trapezoidal as shown in Figure 2 at that time.

The jut 11 that projects in the import cross-sectional area of beater wheel 4 is mentioned the thing to be ground that a part is packed into, thus blade 9 on its whole width, all grab and remain to be ground thing, thereby whole blade 9 is contacted with thing to be ground.Jut 11 makes that part of hot carrying gas together with suction of being mentioned by it in the thing of waiting to grind of packing into produce eddy current simultaneously.Thereby it is dry and cool off self that hot at that time carrying gas makes in this zone rolled-up waiting grind thing, the heat radiation that the carrying gas that therefore can prevent to extract out without utilization is sent, and the carrying gas that exports cross sections by beater wheel 4 has equally distributed temperature.

The operational circumstances of grater is depended in the accurate position of jut 11 on the import sidepiece of blade 9.Therefore jut 11 can be made and can regulate on the length direction of blade 9.The position can be selected like this, makes to go out wheel 4 and waited to grind thing and hot carrying gas as far as possible equably and impact.According to accompanying drawing beginning the time jut 11 can be located at the very approaching position of the preceding annular disk of beater wheel 4 on.This position is counted as particularly advantageous.

According to the design of percussive wheel pulverising machine, beater wheel 4 can be equipped with 8 to 16 blades.All these blades 9 all can be provided with jut 11.But also can have only individual blade 9 to be provided with a jut 11.When adopting the blade of even number, two relative blades 9 should at least respectively have a jut 11, so that prevent the imbalance of beater wheel.Though the arrangement of a kind of like this symmetry is favourable, on the other hand, have bigger weight owing to go out wheel 4, some also is an acceptable owing to the imbalance that jut 11 causes is set on blade 9 asymmetricly.

Claims

1. percussive wheel pulverising machine, having one is located in the grater housing (1) and is fixed tightly in the beater wheel (4) that grinds on the arbor (5), this beater wheel has radially outlet and at two disks (7 of an axial inlet and, 8) be provided with a plurality of blades (9) between, it is characterized in that, on the partial width of blade (9), establish a jut (11) in the import cross-sectional area that protrudes inwardly into beater wheel (4) on one side inwardly of at least one blade (9), described jut (11) is located at the position near the import of beater wheel (4), and has a width that is equivalent to the 1-40% of blade (9) width.

2. according to the grater of claim 1, it is characterized in that the height maximum of jut (11) can be suitable with the total height of blade (9).

3. according to the grater of claim 1 or 2, it is characterized in that all blades (9) of beater wheel (4) all are provided with jut (11).

4. according to the grater of claim 1 or 2, it is characterized in that having only partial blade (9) to be provided with jut (11) on the beater wheel (4).

5. according to the grater of claim 4, it is characterized in that the blade (9) that beater wheel (4) is provided with jut (11) is that symmetry is arranged.

6. according to the described grater of claim 1, it is characterized in that jut (11) can be in its position of length direction adjusted of blade (9).

7. according to the described grater of claim 1, it is characterized in that described jut (11) has 5～20% the width that is equivalent to blade (9) width.