CN219463671U

CN219463671U - Air ring of medium-speed coal mill

Info

Publication number: CN219463671U
Application number: CN202320813865.4U
Authority: CN
Inventors: 王勇
Original assignee: Hunan Huadian Changde Power Generation Co ltd
Current assignee: Hunan Huadian Changde Power Generation Co ltd
Priority date: 2023-04-12
Filing date: 2023-04-12
Publication date: 2023-08-04
Anticipated expiration: 2033-04-12

Abstract

The utility model relates to the field of air rings, in particular to an air ring of a medium-speed coal mill. The wind ring of the medium-speed coal mill comprises a static ring and a dynamic ring; the section of the stationary ring (1) is a right triangle conical surface, and the outlet edge of the movable ring (2) is a round angle; the hypotenuse of the right triangle of the section of the stationary ring (1) and the circumscribed line of the round angle of the outlet edge of the movable ring (2) are positioned on the same straight line; the included angle between the hypotenuse of the right triangle of the section of the static ring (1) and the horizontal plane is 30-45 degrees. The utility model improves the wind ring structure of the medium-speed coal mill, is beneficial to the uniformity of a flow field, and avoids the problems of nest wind, high flow resistance, serious abrasion of the surface flow part of the static ring and the like after the rectified primary wind flowing out of the dynamic ring enters the static ring.

Description

Air ring of medium-speed coal mill

Technical Field

The utility model relates to the field of wind rings, in particular to a wind ring of a coal mill.

Background

The domestic coal-fired power plant boiler system mostly adopts a medium-speed coal mill, and the main function is to grind raw coal into coal dust, and the ground coal dust is sent to the boiler for combustion by primary air. However, the existing medium-speed coal mill has a series of problems such as high resistance, low output of the coal mill, high electricity consumption and the like. The root of the wind ring is that the wind ring has an unreasonable structure, which causes uneven dynamic field and large resistance.

Disclosure of Invention

The flow of the dynamic field is influenced by a plurality of factors, and the problems of high resistance, low output of the coal mill, high power consumption and the like are solved by starting from through-flow structural factors such as the driven ring outlet, the static ring inlet and the like.

The wind ring of the medium-speed coal mill comprises a static ring and a dynamic ring;

the section of the stationary ring (1) is a right triangle conical surface, and the outlet edge of the movable ring (2) is a round angle;

the hypotenuse of the right triangle of the section of the stationary ring (1) and the circumscribed line of the round angle of the outlet edge of the movable ring (2) are positioned on the same straight line;

the included angle between the hypotenuse of the right triangle of the section of the static ring (1) and the horizontal plane is 30-45 degrees.

The utility model improves the wind ring structure of the medium-speed coal mill, is beneficial to the uniformity of a flow field, and avoids the problems of nest wind, high flow resistance, serious abrasion of the surface flow part of the static ring and the like after the rectified primary wind flowing out of the dynamic ring enters the static ring.

The utility model solves the flow direction of the air flow at the outlet of the movable ring in the rotation process of the air ring, reduces the resistance of the transition part of the movable ring and the static ring, reduces the phenomenon of wind nest at the inlet of the static ring, ensures that the flow field becomes more uniform, and improves the output of the coal mill.

The utility model has simple structure, convenient installation, low processing precision and low processing and manufacturing cost; the service life is long, and the safety and reliability are realized; and no maintenance is required.

Drawings

FIG. 1 is a schematic diagram of a cross-sectional structure of a wind ring of a medium speed coal mill;

fig. 2 is an enlarged view of the section I in fig. 1.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, without conflict, the embodiments of the present utility model and features of the embodiments may be combined with each other.

The first embodiment is as follows: 1-2, the wind ring of the medium speed coal mill in the embodiment comprises a static ring and a dynamic ring;

the included angle between the hypotenuse of the right triangle of the section of the static ring (1) and the horizontal plane is 30-45 degrees;

the relative installation positions of the stationary ring (1) and the movable ring (2) are provided with certain overlapping surfaces in the horizontal direction and the vertical direction, wherein the overlapping surface clearance in the horizontal direction is 6-8mm, and the overlapping surface clearance in the vertical direction is 6-8mm.

Working principle:

the primary air with opposite flow directions and falling coal dust are subjected to violent collision at the air ring, and the primary air supports a large amount of coal with smaller density, separates and blows up fine coal dust, and enters the coal dust pipeline after being further separated by the dynamic separator. The rationality of the structure at the wind ring influences the uniformity of mixing of primary wind and coal dust and the powder outlet efficiency, thereby influencing the output of the coal mill. The wind ring structure of the medium speed coal mill adopts smooth transition of the static ring inlet edge and the movable ring outlet edge, ensures uniformity of a flow field, is favorable for primary wind to flow along the static ring oblique edge, effectively guides airflow to avoid nest wind phenomenon at the static ring inlet, guides airflow to the edge part of the coal mill, reduces effective primary wind resistance through the movable ring, reduces abrasion of wind-powder mixture on the surface of the static ring, increases output of the coal mill, and reduces electricity consumption. Meanwhile, as the inlet side of the stationary ring adopts a triangular structure, the coverage of the inlet side and the outlet side of the movable ring is increased, so that the axial gap between the movable ring and the stationary ring is lengthened, the resistance of ineffective air leakage is increased, the ineffective primary air quantity which is not rectified by the movable ring is reduced, the useful primary air quantity is improved, and the ventilation output of the coal mill is increased.

The second embodiment is as follows: the present embodiment differs from the first embodiment in that: the central angle corresponding to the circular bead at the outlet edge of the movable ring (2) is 50-90 degrees, and the circular arc radius of the circular bead is 10-30 mm. The other is the same as in the first embodiment.

And a third specific embodiment: the present embodiment differs from the first or second embodiment in that: the relative installation positions of the stationary ring (1) and the movable ring (2) are provided with certain overlapping surfaces in the horizontal direction and the vertical direction, wherein the overlapping surface gap in the horizontal direction is 8-10 mm, and the overlapping surface gap in the vertical direction is 8-10 mm. The other is the same as in the first embodiment.

Claims

1. The medium speed coal mill wind ring comprises a static ring and a dynamic ring;

the method is characterized in that: the section of the stationary ring (1) is a right triangle conical surface, and the outlet edge of the movable ring (2) is a round angle;

2. The medium speed coal mill wind ring according to claim 1, characterized in that the central angle corresponding to the round angle of the outlet edge of the moving ring (2) is 50-90 degrees, and the radius of the round angle is 10-30 mm.

3. The medium speed coal mill wind ring according to claim 1, characterized in that the relative installation positions of the stationary ring (1) and the movable ring (2) are provided with a certain overlapping surface in both horizontal and vertical directions, wherein the overlapping surface gap in the horizontal direction is 6-10mm, and the overlapping surface gap in the vertical direction is 6-10mm.