Sieve hole guide nozzle ring of medium-speed coal mill

Abstract

The utility model relates to the technical field of coal mill gas inlet auxiliary devices, in particular to a medium-speed coal mill sieve hole guide nozzle ring, which comprises a movable nozzle ring and a static nozzle ring, the movable nozzle ring is fixed on a millstone, the static nozzle ring is fixed on the inner side of a frame body, a support is fixed on the inner side of the frame body, and the fixed nozzle ring is fixed on the support body. The static nozzle ring is fixed to the upper portion of the support through a bolt, and the nozzle is characterized in that a sieve hole guide assembly is arranged on the lower portion of the movable nozzle ring and comprises an outer sieve hole guide ring, an inner sieve hole guide ring and a plurality of sieve holes, the outer sieve hole guide ring and the inner sieve hole guide ring are fixed to the lower portion of the movable nozzle ring, and the sieve holes are formed in the outer sieve hole guide ring and the inner sieve hole guide ring. And the plurality of sieve pores are uniformly distributed on the inner sieve pore guide ring. By adjusting the air quantity uniformity of the nozzle of the movable nozzle ring, the air quantity of the nozzle of the nozzle ring adapts to the coal quality working conditions of multiple coal types, and the requirements for reducing the local wear rate of the coal mill and the like are met.

Description

TECHNICAL FIELD

[0001] The utility model relates to coal mill gas inlet auxiliary device technical field especially relates to a screen hole guide nozzle ring of medium speed coal mill. BACKGROUND

[0002] The primary mixed hot air of medium speed coal mill enters the grinding area from bottom to top through the nozzle ring, and the nozzle ring is used to improve the air speed and make the air flow distribution more uniform. The air speed of the nozzle ring nozzle is designed according to the designed coal quality. When the coal mill grinds the coal with higher moisture content than the designed coal, in order to meet the drying output of the coal mill, the system needs to provide a larger air volume, which will result in higher air speed at the nozzle ring air port of the coal mill, accelerate the wear of the internal structure of the coal mill, and greatly reduce the service life of the equipment. When the coal with lower moisture content than the designed coal is ground, the system needs to provide a smaller air volume, and at this time, the air speed at the nozzle ring air port is lower, which will result in increased slag discharge of the coal mill. Therefore, the original fixed and non-adjustable nozzle ring cannot adapt to the situation of large change of coal quality, and can only be replaced by the method of replacing the nozzle ring. The process of replacing the nozzle ring is very complicated. First, the coal mill can be shut down for maintenance under the condition that the power station power load is not high, and the replacement method of the nozzle ring of different types of medium speed coal mill is also different. The screen hole guide nozzle ring can adapt to various coal qualities by replacing the outer screen hole guide ring, the inner screen hole guide ring and the folding guide plate in the coal mill under the condition that the unit does not stop, and can adjust the air volume uniformity and the coal powder uniformity in the coal mill. The design of the trapezoidal coal dam makes the coal bed in the coal mill thicker, reduces the collision probability of the roller sleeve and the grinding disc tile, and thus reduces the vibration probability of the coal mill. SUMMARY

[0003] The utility model solves the technical scheme adopted by technical problems thereof is:

[0004] A screen hole guide nozzle ring of medium speed coal mill, including dynamic nozzle ring and static nozzle ring, the dynamic nozzle ring is fixed on the grinding disc, the static nozzle ring is fixed in the inside of frame body, the inside of frame body is fixed with support, the static nozzle ring is fixed on the upper portion of support through bolt, the lower portion of dynamic nozzle ring is equipped with screen hole guide component, the screen hole guide component includes: outer screen hole guide ring, inner screen hole guide ring and a plurality of screen holes, the outer screen hole guide ring and inner screen hole guide ring are fixed below dynamic nozzle ring, the plurality of screen holes are evenly distributed on inner screen hole guide ring, the screen hole guide component further includes folding guide plate, and the folding guide plate is fixedly connected with outer screen hole guide ring and inner screen hole guide ring.

[0005] Preferably, the screen hole arrangement is annular, staggered or radial.

[0006] Preferably, the screen hole design angle is 0° to 90°.

[0007] Preferably, the diameter of the screen hole ranges from 3mm to 10mm, and the number of screen holes is 50 to 200.

[0008] Preferably, a coal blocking dam is arranged on the upper part of the movable nozzle ring close to the inner side, the coal blocking dam is uniformly segmented along the circumferential direction of the movable nozzle ring, and the cross section is trapezoidal and made of wear-resistant material.

[0009] Preferably, the upper part of the static nozzle ring (2) is covered with a segmented wear-resistant lining plate (3) along the circumferential direction thereof

[0010] The utility model has the advantages that:

[0011] The utility model discloses a movable nozzle ring nozzle air volume uniformity is adjusted to make the nozzle ring nozzle air volume adapt to the coal quality condition of multiple coals, and the local wear rate of the coal mill is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without paying the creative labor.

[0013] Fig. 1 It is the whole structure schematic diagram of the utility model;

[0014] Fig. 2 It is the schematic diagram of the screen hole of the utility model;

[0015] Fig. 3 It is the local schematic diagram of the screen hole of the utility model;

[0016] In the drawing: 1, frame body;2, static nozzle ring;3, wear-resistant lining plate;4, support;5, coal dam;6, movable nozzle ring;7, outer screen hole guide ring;8, deflection guide plate;9, inner screen hole guide ring;10, screen hole. DETAILED DESCRIPTION

[0017] In order to make the technical means, creative features, purposes and effects of the utility model easy to understand, the following will further describe the utility model in combination with specific embodiments.

[0018] Please refer to Figs. 1-3 The utility model provides a technical scheme:

[0019] A screen hole guide nozzle ring of a medium-speed coal mill, comprising a dynamic nozzle ring 6 fixed on a grinding disc and a static nozzle ring 2 fixed inside a frame body 1, wherein a support 4 is fixed inside the frame body 1, the static nozzle ring 2 is fixed on the upper part of the support 4 by bolts, the lower part of the dynamic nozzle ring 6 is provided with a screen hole guide assembly, the screen hole guide assembly comprises an outer screen hole guide ring 7, an inner screen hole guide ring 9 and a plurality of screen holes 10, the outer screen hole guide ring 7 and the inner screen hole guide ring 9 are fixed below the dynamic nozzle ring 6, the plurality of screen holes 10 are uniformly distributed on the inner screen hole guide ring 9, and the screen hole guide assembly further comprises a deflection guide plate 8 fixedly connected with the outer screen hole guide ring 7 and the inner screen hole guide ring 9.

[0020] The screen holes 10 are arranged in a ring shape, staggered distribution or radial arrangement.

[0021] The design angle of the screen holes 10 is 0-90 degrees.

[0022] The diameter of the screen holes 10 ranges from 3mm to 10mm, and the number of the screen holes is 50-200.

[0023] The upper part of the dynamic nozzle ring 6 is provided with a coal dam 5 close to the inner side, the coal dam 5 is uniformly segmented along the circumferential direction of the dynamic nozzle ring 6 and has a trapezoidal cross section and is made of wear-resistant material.

[0024] The upper part of the static nozzle ring 2 is covered with a segmented wear-resistant lining plate 3 along the circumferential direction.

[0025] The static nozzle ring 2, the dynamic nozzle ring 6, the coal dam 5, the outer screen hole guide ring 7, the deflection guide plate 8 and the inner screen hole guide ring 9 are of a split structure and are divided into 4-12 segments.

[0026] Referring to Figs. 1-3 The inner surface of the frame body 1 of the coal mill is welded with the support 4, the dynamic nozzle ring 6 of the split structure is connected on the rotating grinding disc by bolts, the coal dam 5 is fixed on the dynamic nozzle ring 6 by bolts, the outer screen hole guide ring 7, the deflection guide plate 8 and the inner screen hole guide ring 9 are welded or bolted below the dynamic nozzle ring 6, the outer screen hole guide ring 7 and the deflection guide plate 8 are welded, and the deflection guide plate 8 and the inner screen hole guide ring 9 are welded, the static nozzle ring 2 is fixed on the support 4 by bolts, adjusting shims are inserted between the static nozzle ring 2 and the support 4 for adjusting the gap between the dynamic nozzle ring 6 and the static nozzle ring 5, and the wear-resistant lining plate 3 of the split structure is fixed on the static nozzle ring 2.

[0027] The working process of the application is as follows:

[0028] When the device is in use, the mixed hot air is first introduced into the movable nozzle ring 6 through the air duct composed of the outer screen hole guide ring 7, the deflection guide plate 8 and the inner screen hole guide ring 9, and then distributed and optimized in flow through the screen holes 10, the number and angle of the screen holes 10 make the air flow form a ring-shaped uniform distribution of air pressure after being guided, while reducing air flow turbulence and reducing impact on the grinding disc. The coal mill realizes that the air volume of each nozzle of the movable nozzle ring 6 is uniformly distributed on the upper grinding area of the grinding disc by installing the outer screen hole guide ring 7, the deflection guide plate 8, the inner screen hole guide ring 9 and the screen holes 10 below the movable nozzle ring 6.

[0029] The basic principle, main features and advantages of the present application are shown and described above. Those skilled in the art should understand that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A screen guide nozzle ring of a medium speed coal mill, comprising a moving nozzle ring (6) fixed on a grinding table and a static nozzle ring (2) fixed inside a frame (1), the inside of the frame (1) is fixed with a support (4), the static nozzle ring (2) is on the upper part of the support (4), characterized in that, The lower part of the moving nozzle ring (6) is provided with a sieve hole guide assembly, which comprises an outer sieve hole guide ring (7), an inner sieve hole guide ring (9) and a plurality of sieve holes (10), the outer sieve hole guide ring (7) and the inner sieve hole guide ring (9) are fixed below the moving nozzle ring (6), the plurality of sieve holes (10) are uniformly distributed on the inner sieve hole guide ring (9), and the sieve hole guide assembly further comprises a deflection guide plate (8), the deflection guide plate (8) is fixedly connected with the outer sieve hole guide ring (7) and the inner sieve hole guide ring (9).

2. A sizing nozzle ring for a medium speed coal mill as claimed in claim 1, wherein, The arrangement mode of the sieve hole (10) is annular uniform distribution, staggered distribution or radial arrangement.

3. A sizing nozzle ring for a medium speed coal mill as claimed in claim 2, wherein, The design angle of the sieve hole (10) is 0° to 90°.

4. A sizing nozzle ring for a medium speed coal mill as claimed in claim 3, wherein, The diameter of the sieve hole (10) ranges from 3mm to 10mm, and the number of sieve holes ranges from 50 to 200.

5. A sizing nozzle ring for a medium speed coal mill as claimed in claim 1, wherein, The upper part of the moving nozzle ring (6) is provided with a coal blocking dam (5) near the inner side, the coal blocking dam (5) is uniformly segmented along the circumferential direction of the moving nozzle ring (6), and the cross section is trapezoidal, and the wear-resistant material is adopted.

6. A sizing nozzle ring for a medium speed coal mill as claimed in any one of claims 1 to 5, wherein, The upper part of the static nozzle ring (2) is covered with a segmented wear-resistant lining plate (3) along the circumference thereof.

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