Hot primary air shut-off door for direct-fired pulverizing system of thermal power plant

Abstract

The utility model discloses a hot primary air shut-off door for a direct-blowing pulverizing system of a thermal power plant, which is characterized in that the hot primary air shut-off door is arranged on a horizontal air duct, door plates are opened along a medium flowing direction and are opened and closed against the medium flowing direction, and the hot primary air shut-off door comprises a door body for connecting a front air duct and a rear air duct, two door plates arranged oppositely and a main cylinder for driving the door plates, the door plate is integrally connected to the door shaft and arranged in the door body, the main air cylinder is fixed to the door body, and a piston rod of the main air cylinder is connected with the door shaft through the execution crank arm. By the adoption of the double-door design, the door plate is located behind the door seat when being opened and attached to the wall of the air duct, abrasion caused by medium scouring is avoided, the service life of the valve is guaranteed, the sealing effect is improved, meanwhile, the locking device is adopted, and it is further guaranteed that the door plate is closed tightly without leakage; and sealing air is introduced to seal the sealing cavity, dust is prevented from entering and abrading the shaft seal, and the service life of the shaft seal is guaranteed.

Description

Technical Field

[0001] The utility model relates to an air duct shut-off door, in particular to a hot primary air shut-off door for a direct-blowing pulverizing system of a thermal power plant. Background Art

[0002] The pulverizing system of a thermal power plant is mainly composed of a coal feeder, a coal mill, a primary fan, a sealed fan and ancillary accessories. The primary fan mixes the hot primary air heated by the air preheater with the unheated cold primary air in a certain ratio and sends the hot air into the coal mill, and then sends the qualified pulverized coal into the furnace. The hot primary air duct shutoff door is set before the coal mill and after the hot air regulating valve and the cold air regulating valve. As a key device to isolate the hot air from the coal mill, it is the most important safety measure to ensure that the coal mill can be entered for maintenance during the operation of the unit. Its tightness after closing directly determines whether the maintenance conditions are met, and it is an important factor affecting the safe production of thermal power plants.

[0003] At present, the hot primary air damper of thermal power plants generally adopts a plug-in plate structure, which has certain design defects. When in use, there are disadvantages such as poor sealing of the door panel, frequent feedback failures, stuck switches, and serious dust accumulation inside. Utility Model Content

[0004] The utility model aims to provide a hot primary air shut-off door for a direct-blowing pulverizing system of a thermal power plant, so as to solve the shortcomings of the prior art such as poor sealing of the door plate and serious internal dust accumulation.

[0005] The utility model is implemented by adopting the following technical scheme: a hot primary air shut-off door for a direct-blowing pulverizing system of a thermal power plant, characterized in that it is arranged on a horizontal air duct, the door panel is opened in the direction of medium flow, and opened and closed in the opposite direction of medium flow, comprises a door body connected to the front and rear air ducts, two door panels arranged opposite to each other, and a main cylinder for driving the door panel, the door panel is integrally connected to the door shaft and arranged in the door body, the main cylinder is fixed on the door body, and the piston rod of the main cylinder is connected to the door shaft through an actuator crank arm.

[0006] Furthermore, a door frame is provided in the door body, a packing groove is provided in the door frame, both ends of the door shaft are connected to the door body through bearings, and a sealing chamber is provided at the bearing connection part of the door shaft.

[0007] Furthermore, a locking device is also provided in the door body, and the locking device includes a locking shaft and a locking cylinder driving the locking shaft. A locking block is integrally connected to the locking shaft. There are two locking shafts, which are respectively arranged at the upper and lower parts of the door frame. Each locking shaft is connected to a locking cylinder, and the piston rod of the locking cylinder is connected to the locking shaft through an actuator arm.

[0008] Furthermore, both ends of the locking shaft are connected to the door body bearings, and a sealing chamber is provided at the locking shaft bearing connection portion.

[0009] Furthermore, the axial direction of the locking shaft, the axial direction of the door shaft, and the medium flow direction are perpendicular to each other.

[0010] Furthermore, a sealed air duct is also provided in the door body, and the sealed air duct connects the sealed chamber with the external sealed air.

[0011] The utility model discloses a hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant. By adopting a double-door design, when the door panel is opened, it is located behind the door seat and fits the wall of the air duct, thereby avoiding wear caused by medium scouring, ensuring the service life of the valve and improving the sealing effect. At the same time, a locking device is adopted to further ensure that the door panel is tightly closed without leakage. By designing a sealing chamber at the shaft seal position and connecting the sealing air to seal the sealing chamber, dust is prevented from entering and wearing the shaft seal, thereby ensuring the service life of the shaft seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. The drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0013] Figure 1 A schematic diagram of a hot primary air shutoff door for a direct-blowing pulverizing system in a thermal power plant;

[0014] In the figure: 1-main cylinder; 2-locking cylinder; 3-actuator arm; 4-door shaft; 5-locking shaft; 6-sealed chamber; 7-sealed air duct; 8-door panel; 9-air duct; 10-door frame; 11-sealed air interface. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0016] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] like Figure 1 As shown, a hot primary air shut-off door for a direct-blowing pulverizing system of a thermal power plant comprises a main cylinder 1, a door shaft 4 and a door plate 8, wherein the door shaft 4 is keyed with an actuating arm 3, the piston rod of the main cylinder 1 is connected to the actuating arm 3 by a pin, and the door plate 8 is welded to the door shaft 4, wherein there are two door plates 8, which are arranged in opposite directions. The door plate 8 and the door shaft 4 are arranged in the door body, and the two ends of the door body are respectively welded and connected with the front and rear air ducts 9, a door frame 10 is arranged in the door body, the door shaft 4 is arranged on both sides of the door frame 10, the door frame 10 is arranged in the door body by welding, and a packing groove is opened, and a high-temperature resistant high-carbon fiber sealing material is used to seal with the door plate, and the door plate 8 is located behind the door seat when opened, and is attached to the air duct wall to avoid wear caused by medium erosion; the door seat seal is designed on the leeward side to avoid medium erosion, effectively protect the door seat sealing surface, and at the same time achieve double protection of the door plate 8 and the door seat to ensure the service life of the valve.

[0018] The shut-off door is also provided with a locking device, which includes a locking cylinder 2 and a locking shaft 5, wherein the locking cylinder 2 and the locking shaft 5 are connected via an actuating arm 3, there are two locking shafts 5, which are respectively arranged at the upper and lower sides of the door frame 10, and a locking block is welded on the locking shaft 5. The locking device is provided with two locking cylinders 2 in the vertical direction as a power source, which drives the locking shaft 5 to rotate. In the locked state, the locking block rotates the locking shaft 5 to compact the door panel 8, thereby realizing the locking action; in the unlocked state, the locking block rotates the locking shaft 5 to loosen the door panel 8, thereby realizing the unlocking action.

[0019] The locking shaft 5 and the door shaft 4 are respectively connected to the door body bearings, and the connecting ends of the locking shaft 5 and the door shaft 4 are both provided with a sealed chamber 6, wherein a sealed air duct 7 is provided on the upper part of the door body, and the sealed air duct 7 connects the sealed chamber 6 with the external sealed air, and a sealed air interface 11 is provided on the sealed air duct 7, and the external sealed air is connected through the sealed air interface 11, thereby ensuring the sealing effect of the sealed chamber 6 and ensuring the service life of the bearings at the same time.

[0020] The above embodiments describe the basic principle and main features of the utility model and the advantages of the utility model. The technicians in this industry should understand that the utility model is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the changes and modifications made by the technicians in this field shall be within the scope of protection of the claims attached to the utility model.

Claims

1. A hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant, characterized in that: The invention comprises a door body connected to front and rear air ducts, two door panels (8) arranged to open opposite to each other, and a main cylinder (1) for driving the door panels (8), wherein the door panels (8) are integrally connected to a door shaft (4) and arranged in the door body, the main cylinder (1) is fixed to the door body, and a piston rod of the main cylinder (1) is connected to the door shaft (4) via an actuating arm (3). The hot primary air shut-off door for a direct-blowing pulverizing system of a thermal power plant is arranged on a horizontal air duct, and the door panels (8) are opened in the direction of medium flow and closed in the direction opposite to the medium flow.

2. The hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant according to claim 1, characterized in that: A door frame (10) is also provided in the door body, the door frame (10) is provided with a packing groove, and both ends of the door shaft (4) are connected to the door body via bearings.

3. The hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant according to claim 1, characterized in that: A sealing chamber (6) is provided at the bearing connection portion of the door shaft (4).

4. The hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant according to claim 1, characterized in that: The door body is also provided with two sets of upper and lower locking devices, the locking devices comprising a locking shaft (5) and a locking cylinder (2) driving the locking shaft (5), the locking shaft (5) being integrally connected with a locking block, the locking shaft (5) being connected to a locking cylinder (2), and the piston rod of the locking cylinder (2) being connected to the locking shaft (5) via an actuating crank arm (3).

5. The hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant according to claim 4, characterized in that: Both ends of the locking shaft (5) are connected to the door body bearings, and a sealing chamber (6) is provided at the bearing connection portion of the locking shaft (5).

6. The hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant according to claim 4, characterized in that: The axial direction of the locking shaft (5), the axial direction of the door shaft (4) and the medium flow direction are perpendicular to each other.

7. The hot primary air shut-off door for a direct-blowing pulverizing system in a thermal power plant according to claim 1, characterized in that: A sealed air duct (7) is also provided in the door body, the sealed air duct (7) is connected to the sealed chamber (6), and the sealed air duct (7) is connected to an external sealed air port via a sealed air interface (11).

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