阅读说明：本技术 一种契合接触式空预器径向密封系统 (Radial sealing system of fit contact type air preheater ) 是由 王振市 徐美召 丁浩 杜华峰 杨建宇 于 2020-07-31 设计创作，主要内容包括：本发明公开了一种契合接触式空预器径向密封系统,属于空预器密封装置技术领域。本发明包括设置在热端扇形密封板和热端径向隔板之间的径向密封装置,径向密封装置包括上密封单元和下密封单元,上密封单元和下密封单元的结构相同,其中上密封单元包括设置在热端扇形密封板下部的固定板,固定板的一端底部铰接设置有摩擦块底座,摩擦块底座的顶部设置有复位弹簧,复位弹簧的顶部通过支撑板固定在固定板上,摩擦块底座下方还设置有摩擦块,上摩擦块和下摩擦块的截面为对称设置的梯形结构。本发明的目的在于克服现有空预器密封在满负荷情况下空预器径向漏风增大的问题,通过上、下密封面的相互契合,能够降低空预器的径向漏风。(The invention discloses a fit contact type air preheater radial sealing system, and belongs to the technical field of air preheater sealing devices. The hot end fan-shaped sealing plate comprises a radial sealing device arranged between a hot end fan-shaped sealing plate and a hot end radial partition plate, wherein the radial sealing device comprises an upper sealing unit and a lower sealing unit, the upper sealing unit and the lower sealing unit are identical in structure, the upper sealing unit comprises a fixing plate arranged at the lower part of the hot end fan-shaped sealing plate, a friction block base is hinged to the bottom of one end of the fixing plate, a reset spring is arranged at the top of the friction block base, the top of the reset spring is fixed on the fixing plate through a supporting plate, a friction block is further arranged below the friction block base, and the sections of the upper friction block and the lower friction block are of symmetrically. The invention aims to solve the problem that the radial air leakage of the existing air preheater is increased under the full-load condition, and the radial air leakage of the air preheater can be reduced through mutual matching of the upper sealing surface and the lower sealing surface.)

1. The utility model provides a agree with radial sealing system of contact air preheater which characterized in that: comprises a radial sealing device (200) arranged between a hot end fan-shaped sealing plate (110) and a hot end radial clapboard (130) of a rotor (100), wherein the radial sealing device (200) comprises an upper sealing unit (201) arranged at the lower part of the hot end fan-shaped sealing plate (110) and a lower sealing unit (201) arranged at the upper part of the hot end radial clapboard (130), the upper sealing unit (201) and the lower sealing unit (201) have the same structure and are symmetrically distributed, the upper sealing unit (201) comprises a fixing plate (210) arranged at the lower part of the hot end fan-shaped sealing plate (110), the bottom of one end, far away from the hot end fan-shaped sealing plate (110), of the fixing plate (210) is hinged with a friction block base (250), the top of the friction block base (250) is provided with a return spring (240), and the top of the return spring (240) is fixed on the fixing plate (210) through a supporting plate (220); lower seal unit (201) is including setting up fixed plate (210) on hot junction radial baffle (130) upper portion, the one end top that hot junction radial baffle (130) was kept away from in fixed plate (210) articulates and is provided with clutch blocks base (250), the bottom of clutch blocks base (250) is provided with reset spring (240), the top of reset spring (240) is passed through backup pad (220) and is fixed on fixed plate (210), clutch blocks base (250) below is provided with clutch blocks (260), and the section of clutch blocks (260) of last seal unit (201) and clutch blocks (260) of lower seal unit (201) is the trapezium structure of symmetry setting.

2. A compliant contact air preheater radial seal system according to claim 1, wherein: a ball head screw rod (230) is arranged between the supporting plate (220) and the friction block base (250), a spherical head (231) of the ball head screw rod (230) is connected with the friction block base (250), and the tail of the ball head screw rod (230) penetrates through a preformed hole in the supporting plate (220) and is locked and fixed through a pair of locking nuts (233).

3. A compliant contact air preheater radial seal system according to claim 2, wherein: one side of keeping away from clutch blocks (260) on clutch blocks base (250) is provided with head support (232), has seted up in head support (232) with spherical head (231) size matched with arc recess, spherical head (231) card is in the arc recess.

4. A compliant contact air preheater radial seal system according to claim 1, wherein: the bottom of the friction block (260) of the upper sealing unit (201) is gradually raised along the direction away from the hinge point, and the bottom of the friction block (260) of the lower sealing unit (201) is gradually lowered along the direction away from the hinge point.

5. A compliant contact air preheater radial seal system according to claim 1, wherein: the length of a fixing plate (210) of an upper sealing unit (201) is consistent with the radial length of a hot end fan-shaped sealing plate (110), the length of the fixing plate (210) of a lower sealing unit (201) is consistent with the radial length of a hot end radial partition plate (130), the length of a supporting plate (220) and the length of a friction block base (250) are consistent with the length of the fixing plate (210), and a plurality of return springs (240) are uniformly arranged between the supporting plate (220) and the friction block base (250) along the length direction.

6. A compliant contact air preheater radial seal system according to claim 1, wherein: connecting holes are formed in the positions, corresponding to the fixing plate (210), of the hot end fan-shaped sealing plate (110), and fixing bolts (211) sequentially penetrate through the fixing plate (210) and the hot end fan-shaped sealing plate (110) and are fixed together through fixing nuts (212).

7. A compliant contact air preheater radial seal system according to claim 6, wherein: the connecting holes on the fixing plate (210) are waist-shaped holes.

8. A compliant contact air preheater radial seal system according to claim 7, wherein: the hot end fan-shaped sealing plate (110) and the fixing plate (210) are both provided with a plurality of connecting holes along the length direction, and a plurality of fixing bolts (211) sequentially penetrate through the fixing plate (210) and the hot end fan-shaped sealing plate (110) and are fixed together through fixing nuts (212).

9. A conformable contact air preheater radial seal system according to any one of claims 1 to 8, wherein: the radial sealing device (200) is arranged between the cold end fan-shaped sealing plate (120) and the cold end radial partition plate (140) of the rotor (100).

10. A compliant contact air preheater radial seal system according to claim 9, wherein: the friction block (260) is made of nickel-based alloy.

Technical Field

The invention relates to the technical field of air preheater sealing devices, in particular to a fit contact type air preheater radial sealing system.

Background

The radial seal of the air preheater is a fixed seal, namely, the maximum expansion amount of the rotor of the air preheater is estimated, a corresponding gap is reserved, and the gap is compensated by the expansion amount when the equipment runs. Because the expansion amount of the rotor of the air preheater changes along with the change of the load of the unit, and the sector plates of the air preheater are fixed, the sealing clearance can not be adjusted along with the change of the load, so that the sealing clearance can be in the minimum state when the load of the unit reaches the maximum. After the air preheater sealed by the type is put into operation, the air leakage rate is high, generally about 5.5-7%, the maximum air leakage rate can be more than 9%, and the effect is not obvious after overhaul. Furthermore, since the entire weight of the air preheater is transferred to the lower supporting steel beam through the central cylinder, the central cylinder inside the rotor expands upward after being heated, while the outside of the rotor is deformed downward, i.e., exhibits mushroom-type deformation, after being heated and expanded due to its very large diameter and weight. Under the full load condition, the maximum deflection of the outer side of the rotor can reach about 50mm, and the increase of radial air leakage of the air preheater is caused due to the increase of the sealing clearance, so that a series of problems of insufficient air quantity of the coal mill, unstable primary air pressure, influence on combustion and the like are caused, meanwhile, the efficiency of a unit is also seriously influenced, and great economic loss is caused.

Through search, a large number of patents have been published on air preheater sealing devices, such as chinese patent application No.: 2018221361450, the name of invention creation is: the utility model provides an air preheater radial seal device, this application discloses an air preheater radial seal device, includes sector plate and rotor, and the rotor rotates to be installed between two relative sector plates, still includes flexible seal assembly, and the upper and lower surface of rotor is along radially installing the flexible seal assembly of multiunit respectively, and when the rotor rotated for sector plate, flexible seal assembly can be sealed with sector plate flexible contact. According to the scheme, the plurality of groups of flexible sealing assemblies are arranged on the upper surface and the lower surface of the rotor along the radial direction of the rotor, and when the rotor rotates, the flexible sealing assemblies are in flexible contact with the sector plates for sealing, so that the sealing effect can be achieved, rigid contact can be avoided, the sealing effect is good, and the service life is long; when the air preheater rotates, when the sector plate contacts the top of the sliding block, under the pressure action of the sector plate and the deformation action of the sliding block, the contact state of the top of the sliding block and the sector plate is changed into surface contact, and the sealing effect is effectively improved.

Also as in chinese patent application No.: 2012104012808, the name of invention creation is: the application discloses a flexible sealing structure of a rotary air preheater, which is a contact type sealing device and comprises a sealing slide block, an adjusting support seat and a support fixing plate, wherein the sealing slide block is rotatably connected with the support fixing plate, and the support fixing plate is relatively fixed on a radial partition plate of the air preheater; adjusting the supporting seat and supporting the fixed connection, adjusting and being equipped with compression spring between supporting seat and the sealed slider, sealed slider keeps the contact state with air heater's sector plate or axial arc, is equipped with adjusting device that resets between sealed slider and the regulation supporting seat, and adjusting device's both ends that reset are connected with sealed slider and regulation supporting seat respectively for adjust the biggest resilience volume that is located the compression spring between sealed slider and the regulation supporting seat. This scheme is through adjusting the adjusting device that resets, realizes the regulation of the sealed effort between the moving part in the air heater and the static part, reduces the wearing and tearing of sealed face, the life of extension vulnerable part.

The two schemes are good exploration for the air preheater sealing device, but still have further improved space, and research on the air preheater sealing device in the industry is never stopped.

Disclosure of Invention

1. Technical problem to be solved by the invention

The invention aims to solve the problem that the radial air leakage of an air preheater is increased due to the increase of a sealing gap of the existing air preheater under the full-load condition, and provides a fit-contact type air preheater radial sealing system.

2. Technical scheme

In order to achieve the purpose, the technical scheme provided by the invention is as follows:

the invention relates to a fit-contact type radial sealing system of an air preheater, which comprises a radial sealing device arranged between a hot end fan-shaped sealing plate and a hot end radial partition plate of a rotor, wherein the radial sealing device comprises an upper sealing unit arranged at the lower part of the hot end fan-shaped sealing plate and a lower sealing unit arranged at the lower part of the hot end radial partition plate, the upper sealing unit and the lower sealing unit have the same structure and are symmetrically distributed, the upper sealing unit comprises a fixing plate arranged at the lower part of the hot end fan-shaped sealing plate, the bottom of one end of the fixing plate, which is far away from the hot end fan-shaped sealing plate, is hinged with a friction block base, the top of the friction block base is provided with; the lower sealing unit comprises a fixing plate arranged on the upper portion of a hot end radial partition plate, a friction block base is hinged to the top of one end, far away from the hot end radial partition plate, of the fixing plate, a reset spring is arranged at the bottom of the friction block base, the top of the reset spring is fixed to the fixing plate through a supporting plate, a friction block is arranged below the friction block base, and the cross sections of the friction block of the upper sealing unit and the friction block of the lower sealing unit are of symmetrical trapezoid structures.

As a further improvement of the invention, a ball head screw is arranged between the support plate and the friction block base, the spherical head of the ball head screw is connected with the friction block base, and the tail of the ball head screw passes through a preformed hole on the support plate and is locked and fixed by a pair of locking nuts.

As a further improvement of the invention, a head support is arranged on one side of the friction block base, which is far away from the friction block, an arc-shaped groove matched with the size of the spherical head is formed in the head support, and the spherical head is clamped in the arc-shaped groove.

As a further improvement of the invention, the bottom of the friction block of the upper sealing unit is gradually raised along the direction away from the hinge point, and the bottom of the friction block of the lower sealing unit is gradually lowered along the direction away from the hinge point.

As a further improvement of the invention, the length of the fixed plate of the upper sealing unit is consistent with the radial length of the hot end fan-shaped sealing plate, the length of the fixed plate of the lower sealing unit is consistent with the radial length of the hot end radial partition plate, the lengths of the supporting plate and the friction block base are consistent with the length of the fixed plate, and a plurality of reset springs are uniformly arranged between the supporting plate and the friction block base along the length direction.

As a further improvement of the invention, the positions of the hot end fan-shaped sealing plate corresponding to the fixed plate are both provided with connecting holes, and the fixed bolt sequentially penetrates through the fixed plate and the hot end fan-shaped sealing plate and is fixed together through the fixed nut.

As a further improvement of the invention, the connecting holes on the fixing plate are kidney-shaped holes.

As a further improvement of the invention, a plurality of connecting holes are formed on the hot end fan-shaped sealing plate and the fixing plate along the length direction, and a plurality of fixing bolts sequentially penetrate through the fixing plate and the hot end fan-shaped sealing plate and are fixed together through fixing nuts.

As a further improvement of the invention, the radial sealing device is arranged between the fan-shaped sealing plate at the cold end of the rotor and the radial baffle plate at the cold end.

As a further improvement of the invention, the friction block is made of nickel-based alloy.

3. Advantageous effects

Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:

(1) the radial sealing system of the contact-fitting air preheater provided by the invention avoids the problem that a radial sealing part is directly arranged on the hot end radial partition plate like a traditional radial sealing mode, and the radial sealing part on the hot end radial partition plate continuously passes through the lower part of the hot end fan-shaped sealing plate and forms a sealing surface with the bottom surface of the hot end fan-shaped sealing plate, so that the radial sealing of the air preheater is completed. The radial sealing system of the invention simultaneously adjusts the upper sealing unit arranged at the lower part of the hot end fan-shaped sealing plate and the lower sealing unit arranged at the lower part of the hot end radial partition plate up and down, so that the sealing clearance of the air preheater in a mushroom-shaped deformation state is effectively compensated, the sealing clearance of the air preheater in the mushroom-shaped deformation state is effectively compensated, the air preheater is ensured to still ensure good sealing effect under the full-load operation condition, the radial air leakage of the air preheater is effectively reduced, and the unit efficiency and the economic operation level of equipment are improved. Meanwhile, the friction coefficient between the upper friction block and the lower friction block is very small, so that the hot end fan-shaped sealing plate cannot be abraded, the hot end fan-shaped sealing plate can be efficiently protected, and the influence on the current of the air preheater rotor driving motor is reduced.

(2) According to the radial sealing system of the contact-fitting air preheater, when the hot-end radial partition plate runs to the position below the hot-end fan-shaped sealing plate, the friction block of the upper sealing unit is driven to rotate upwards under the action of an upward extrusion force, and the reset spring is extruded upwards; meanwhile, when the friction block of the lower sealing unit is acted by a downward extrusion force, the friction block base is driven to rotate downwards, and the return spring is extruded downwards. The upper friction block and the lower friction block are matched with each other through the movement of the rotor of the air preheater, so that the air preheater can be well self-adjusted even if mushroom-shaped deformation occurs in the air preheater, and a gap generated by the deformation of the air preheater is compensated.

(3) The radial sealing system of the fit-contact air preheater is arranged in a radial multiple sealing mode, namely, when the air preheater rotor rotates at any position, at least two or more groups of radial sealing devices are ensured below each hot-end fan-shaped sealing plate to form more than two layers of sealing surfaces, so that the sealing effect is further enhanced.

(4) According to the radial sealing system of the fit-contact air preheater, the head support is arranged on one side, away from the friction block, of the friction block base, an arc-shaped groove matched with the size of the spherical head is formed in the head support, the spherical head is clamped in the arc-shaped groove and can rotate in the arc-shaped groove at a small angle, the reset spring is sleeved on the periphery of the ball head screw rod, and the ball head screw rod can follow the corresponding position along with the compression of the reset spring and the rotation of the rotating shaft. The ball head screw rod is used for compressing the reset spring to a proper deformation amount, adjusting the mutual stress between the upper friction block and the lower friction block, ensuring the tightness between the upper sealing surface and the lower sealing surface, effectively preventing the reset spring from falling off and facilitating replacement of the reset spring.

(5) According to the radial sealing system of the fit-contact type air preheater, the plurality of reset springs are uniformly arranged between the supporting plate and the friction block base along the length direction, and are used for supporting the friction block base and the friction block to move, so that the movement stability is ensured, and the sealing effect is improved.

(6) The fit contact type radial sealing system of the air preheater further comprises a radial sealing device arranged between the cold end fan-shaped sealing plate and the cold end radial partition plate of the rotor, and the structure of the fit contact type radial sealing system of the air preheater is the same as that of the radial sealing device arranged between the hot end fan-shaped sealing plate and the hot end radial partition plate of the rotor, so that the sealing effect of the hot end fan-shaped sealing plate is ensured, the sealing effect of the cold end fan-shaped sealing plate of the air preheater can be realized, the air leakage rate of the air preheater is further reduced, the efficiency of the boiler is improved, and the.

Drawings

FIG. 1 is a schematic view of the installation structure of a fan-shaped sealing plate at the hot end of an air preheater in the invention;

FIG. 2 is a schematic view of the radial seal of the present invention;

fig. 3 is a sectional view of section a-a in fig. 2.

The reference numerals in the schematic drawings illustrate:

100. a rotor: 110. a hot end fan-shaped sealing plate; 120. a cold end fan-shaped sealing plate; 130. a hot end radial spacer; 140. a cold end radial spacer; 200. a radial seal arrangement; 201. an upper sealing unit; 201. a lower sealing unit; 210. a fixing plate; 211. fixing the bolt; 212. fixing a nut; 220. a support plate; 230. a ball head screw; 231. a spherical head; 232. a head support; 233. locking the nut; 240. a return spring; 250. a friction block base; 260. a friction block; 270. and (4) a hinge shaft.

Detailed Description

For a further understanding of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The present invention will be further described with reference to the following examples.