JPH03129180A - Sealing member for gas preheater - Google Patents

Abstract

PURPOSE:To prevent a sealing member from corrosion by thermal exhaust gas compounds and to stabilize it against thermal shock generated due to rinsing and others by forming at least part of the sealing member of unorganic glass and/or wear and abrasion resistance ceramic the thermal expansion coefficient of which is lower than a specific value. CONSTITUTION:The structure and material of the member in the title are specified by way of using unorganic glass and/or wear and abrasion resistance ceramic the thermal expansion coefficient of which is less than 70X10<-7>/ deg.C at least on one part of sealing parts of a radial sealing part B, an axial sealing part A and a by-pass sealing part C. And all the surfaces except for a sliding surface, supposing ceramic is used for the sliding surface, are formed of wear and abrasion resistance ceramic materially surrounded with anticorrosion steel and anticorrosion steel.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a seal member for a gas preheater.

(Conventional technology) Air preheaters are used in thermal power generation boilers, ship boilers, and other chemical equipment such as oil refining, distillation, and reforming furnaces, by recovering heat from exhaust gas to combustion air through heat exchange, and improving thermal efficiency. It is used to raise the FIG. 23 is a schematic perspective view of the air preheater.

A rotor 5 is rotatably housed in a rotor housing 30, and a radial sealing plate 3 is provided on the side of the rotor 5.
Two pieces 1 are provided on each side of the rotor. The rotor housing 30 is supported by a pedestal (not shown), and the rotor 5 is rotated in the direction of arrow H by a driving device (not shown).

Heat waste gas flows above the rotor 5 as shown by the arrow, and air flows in a counterflow below the rotor 5 as shown by the arrow F.

The exhaust gas layer and the air layer are the radial sealing plate 31
is blocked by A heating element is housed in the rotor 5, and this heating element absorbs heat from the hot exhaust gas D. Then, when the rotor 5 rotates,
When the cold air passes through the heating element, it is heated, and the hot air is sent to a boiler or the like as indicated by arrow G.

On the other hand, since heat is absorbed from the hot exhaust gas, the cold exhaust gas is discharged to the outside air as indicated by arrow E.

In such an air preheater, gaps exist between the outer circumference of the rotor 5 and the rotor housing 30, and between the side surface of the rotor 5 and the radial sealing plate 31, and exhaust gas and air leak from these gaps. Decrease thermal efficiency. Therefore, these gaps should be made as small as possible,
It is important to improve the sealing effect.

(Problems to be Solved by the Invention) The gap between the rotor outer circumference and the housing is sealed by structurally sealing the gap by making the gap as small as possible.

Exhaust gas temperature is 300~400℃, air temperature is between room temperature and 100℃.
degree, and the rotor housing the heating element deforms in response to such temperature changes. In a structural seal, expansion or settling due to such temperature changes increases the gap and reduces the sealing effect.

The gap between the rotor side surface and the radial sealing plate is sealed structurally by minimizing the gap between the 12 or 24 diaphragm plates on the rotor side surface and the metal radial sealing plate. There is.

In such a method, there is a limit to the sealing effect, and when the structural material is corroded by exhaust gas components, the gap becomes larger, reducing the sealing effect.

It is expected that the sealing effect will be improved by eliminating the gap between the seal members and sliding them under pressure.

In addition to the above-mentioned structural sealing problem, rotary air preheaters for boiler combustion used in thermal power plants, etc. use coal, heavy oil, etc. as fuel for the boiler, so sulfur oxides are present in the hot exhaust gas. Contains corrosive gases such as nitrogen oxides, and condensation occurs in the low-temperature parts of the air preheater, making each part of the air preheater susceptible to corrosion. In addition, there is a problem that dust in the heat exhaust gas adheres to various parts such as the heat element of the air preheater, reducing the heat exchange characteristics of the air preheater. It has been implemented. Furthermore, boilers in thermal power plants, etc. are operated continuously for long periods of time, and the downtime of the boilers is extremely short.
The above-mentioned deposits are removed by washing with water in a hot state at .degree. For this reason, there was a problem in that the air preheater parts were subjected to severe thermal shock. Furthermore, the rotary air preheater for boiler combustion used in thermal power plants, etc. is a large device with a roller diameter of 1 to 20 m, and the parts used in the preheater are large, for example, the size of one part is 200 x 100. A seal member with a diameter of 50 mm is used. Therefore, the thermal shock conditions to the sealing member due to the above-mentioned hot water washing are extremely severe.

Sliding members used in rotary air preheaters for boiler combustion in thermal power plants, etc. must have excellent wear resistance, corrosion resistance, and thermal shock resistance, and conventional sealing members are made of SS. Although steel or corrosion-resistant steel has been used, it still has insufficient wear resistance and corrosion resistance, requires frequent maintenance, and is not particularly satisfactory as a sliding member.

An object of the present invention is to provide a sealing member for a gas preheater that has excellent abrasion resistance, is not corroded by hot exhaust gas components, and is stable against thermal shock caused by washing with water or the like.

(Means for Solving the Problems) The present invention provides a sealing member for a gas preheater that seals a gap between the outer periphery of a rotor and a housing of a gas preheater or a gap between a side surface of the rotor and a radial sealing member. The sealing member is characterized in that at least a portion thereof is formed of inorganic glass and/or wear-resistant ceramics having a coefficient of thermal expansion of 70XlO7/°C or less.

Further, the present invention is characterized in that it is made of wear-resistant ceramics and corrosion-resistant steel, in which the sliding surface is made of ceramic and all other surfaces except for the sliding surface are substantially surrounded by corrosion-resistant steel. It is.

(Example) Fig. 1 is a schematic side view of an air preheater, and Fig. 2 is a schematic front view thereof. A rotor 2 held by a rotating shaft l is housed in a housing 3.

The rotor 2 has 12 or 2
It is divided into four parts, and a heating element 5 is installed in each part. The housing is separated into an exhaust gas tank and an air tank, and as the rotor rotates,
The heat of the exhaust gas is stored in a heating element in the exhaust gas tank, and the air is heated in the air tank. Exhaust gas is, for example, 3
50°C, air at 60°C, and when passing through the air preheater, the exhaust gas is cooled to 140°C and the air is heated to 300°C. The air is pressurized and flows into the boiler, and the pressure difference between the air and the exhaust gas is, for example, about 2500 mmaq. Therefore, when air passes through the air preheater, some leakage into the exhaust gas tank occurs due to the pressure difference.

One leakage path occurs through the gap between the diaphragm plate 4 and the radial sealing plate 6 at the side of the rotor. Secondly, it occurs at the outer periphery of the rotor 2 through the gap between the axial sealing plates 7. Further, as the rotor rotates, the exhaust gas and air held in the gap between the heating elements flow into the air tank and the exhaust gas tank, respectively, resulting in leakage.

Seal structures have been devised to minimize such leakage. A method of sealing by making the distance between the diaphragm plate 4 and the radial sealing plate 6 as small as possible is called radial seal B. A method of sealing by minimizing the gap between the axial sealing plate 7 installed on the outer periphery of the rotor and the housing 3 is called axial seal A.

In addition, in order to prevent exhaust gas and air from flowing into the gap between the rotor outer circumference and the housing, a seal member 8 is installed on the side surface of the rotor outer circumference, and the gap with the sealing member 9 attached to the housing 3 is made as small as possible. This method of sealing is called bypass seal C.

The characteristic feature of this example is that at least one of the three seal parts, the radial seal part, the axial seal part, and the bypass seal part, has an inorganic material with a thermal expansion coefficient of 70X10-''/'C or less. Glass and/or wear-resistant ceramics were used, and the structure and material were specified.

Further, the sliding surface is made of abrasion-resistant ceramic and corrosion-resistant steel, with all other surfaces except for the sliding surface being substantially surrounded by corrosion-resistant steel.

First, radial seal B will be explained.

A diaphragm plate 4 extending in the radial direction is provided on the side surface of the rotor 2, and this and a radial sealing plate 6 separate the air side and the exhaust gas side, and perform sealing between the two.

As shown in an enlarged view in FIG. 3, the radial sealing plate 6 has a structure in which a base body 6a and a thin plate 6b are bonded together. The entire base 6a was assembled with corrosion-resistant steel plates or ceramics into the shape shown in FIG. 3, and a thin plate 6b was bonded thereto. This thin plate 6b is made of wear-resistant ceramics or inorganic glass.

The diaphragm plate 4 also has a structure in which a thin plate 4b is provided on a thick base 4a, as shown in FIG. The thin plate 4b may be provided by bonding a thin plate made of ceramics or inorganic glass onto a base 4a made of the same material as the base 6a shown in FIG. 3, or may be provided by enamel or glass lining.

Examples of highly wear-resistant ceramics include silicon nitride, silicon carbide, alumina, mullite, sialon, zirconia, and alumina-containing porcelain. These materials have higher hardness and better wear resistance than metals. In addition, the exhaust gas from the air preheater contains sulfur oxide, nitrogen oxide, etc., which react with water to produce sulfuric acid, sulfurous acid, nitric acid, nitrous acid, etc., but the wear-resistant ceramics mentioned above are effective against these. However, it is stable.

As the inorganic glass and glass lining, so-called acid-resistant enamel is preferable, and examples include those classified into two types of enamel equipment for the chemical industry according to JIS.

Type 1 Nigelas Lining The main ingredients are silicic acid (55% or more), boric acid (0-10%), and alkali (10-20%).

Type 2: Acid-resistant borosilicic acid (40% or more), boric acid (0-10%), and alkali (10-30%) as main components.

Thickness of thin plate 6b, 4b or glass lining is 3mm
The following shall apply.

Among the above wear-resistant ceramics, alumina and zirconia have large coefficients of thermal expansion and are inferior in thermal shock resistance. Base body 6a
, 4a includes ceramics with a coefficient of thermal expansion of 70 x 10-'/°C or less, such as porcelain, mullite, silicon nitride,
It is preferable to use silicon carbide or sialon.

When bonding the substrates 6a, 4a and the ceramic or inorganic glass thin plates 6b, 4b, mechanical bonding is also possible, but from the viewpoint of durability, bonding with inorganic glass or an inorganic adhesive is preferable. preferable.

The radial sealing plate 6 and the diaphragm plate 4 are attached and sealed as shown in FIGS. 1 and 2, with thin plates 6b and 4b made of ceramic or inorganic glass facing each other, respectively. At this time, a slight gap may be provided between the thin plates 6b and 4b, or the thin plates 6b and 4b may be slid under pressure. This pressurization may be applied by an external load or by the weight of the radial sealing plate 6 and the diaphragm plate 4.

According to this example, a layer made of wear-resistant ceramics or inorganic glass is provided on the opposing surfaces of the radial sealing plate and the diaphragm plate, so that the sealing surfaces have high wear resistance and corrosion resistance, and are always A good seal can be achieved. Moreover, the thickness of the wear-resistant ceramic layer is 3
By making the thickness less than mm, the thermal shock resistance of the entire sealing member can be improved even if a material having a high coefficient of thermal expansion such as alumina is used.

In particular, when sliding the radial sealing plate and the diaphragm plate under pressure, abrasion-resistant ceramics or inorganic glass (especially glass lining) is highly effective, preventing deformation, wear, corrosion, etc. of the sealing member. In addition, it is possible to prevent gaps from always occurring, thereby further improving thermal efficiency.

Furthermore, if the coefficient of thermal expansion of the ceramics used for the base of the radial sealing plate or diaphragm plate is 70X to -7/℃ or less, the thermal deformation of the entire sealing member will be further reduced, and the durability against thermal shock caused by washing with water, etc. will be further reduced. Your sexuality will further improve.

The sealing member described above has a high sealing effect and a long service life, and can improve air preheating efficiency in thermal power generation, marine boilers, etc., and can also be used in oil refining, distillation, reforming furnaces, etc. When applied to chemical equipment, the efficiency of heat recovery will be increased. Furthermore, safety during use is increased,
The frequency of maintenance can also be reduced.

In addition, when the base is made of corrosion-resistant steel and a thin plate made of wear-resistant ceramic is bonded to the base, the entire shape of the radial sealing plate etc. is first divided into multiple pieces, and the corresponding thin plate made of corrosion-resistant steel is bonded to each piece. A panel may be created by bonding abradable ceramic thin plates, and a plurality of these panels may be combined to form a radial sealing plate or the like in a predetermined shape. Alternatively, a plurality of panels may be made by enameling the surface of corrosion-resistant steel, and these panels may be combined to form a radial sealing plate or the like in a predetermined shape.

For example, the radial sealing plate 16 shown in FIG.
As shown in the figure, a block 16b made of ceramics or inorganic glass is assembled on the surface of a base 16a made of corrosion-resistant steel so as to form a fan-shaped planar shape as a whole, or a thin plate 16b made of ceramics or inorganic glass is assembled in a similar shape. It can be attached to.

Further, like the radial sealing plate 26 shown in FIG. 6, a plurality of linear ceramic or inorganic glass guides 26b are provided in parallel to each other on the surface of a base 26a made of corrosion-resistant steel, and these guides 26b are connected to a diaphragm plate. It may be slid.

Furthermore, as shown in FIG. 7, a flat ceramic or inorganic glass plate 36b is bonded to the back side of a plate 36a made of corrosion-resistant steel and having a U-shaped cross section to create a composite plate 36. A radial ceiling plate may be produced by combining a large number of sheets to form a quadrilateral shape, fan shape, etc. as a whole.

Next, the axial seal A (see FIG. 1) will be described.

The present invention can also be applied to the axial sealing plate 7, which can have the same shape as the diaphragm plate, as shown in FIG. 4, for example.

That is, like the diaphragm plate shown in FIG. 4, the axial sealing plate 7 is a rod-shaped laminate, with a thin plate 7b provided on a base 7a, and the axial sealing plate and the housing surface facing each other. Preferably,
The axial sealing plate 7 is brought into pressure contact with the rotor 5.
As the housing rotates, the thin plate 7b and the inner surface of the housing are slid under pressure. As a result, an axial seal A is formed between the axial sealing plate 7 and the housing.

The material of the base 7a of the axial sealing plate 7 is as follows:
Just like the diaphragm plate base 7a shown in FIG. 4, it can be made of corrosion-resistant steel or ceramics having a thermal expansion coefficient of 70×10 −7 /° C. or less.

The material of the thin plate of the axial sealing plate is exactly the same as that of the thin plate 7b of the diaphragm plate shown in FIG.
It can be made of wear-resistant ceramics, glass lining, etc. In other respects, the structure may be the same as that of the diaphragm plate 4, and the same effects can be achieved.

Further, an axial sealing plate 17 as shown in FIG. 8 can also be adopted. That is, a metal storage portion 17a having a U-shaped cut surface is fixed to the outer peripheral surface of the rotor 2, and this storage portion 1
A plate-like body 17b made of wear-resistant ceramics is housed in the recess of 7a via a spring 17c, and this plate-like body 17b is attached to the spring 1.
7c to press against the inner surface of the housing to maintain the airtight state by sliding the housing. Since the axial ceiling plate has a small weight, by attaching a spring as in this example, it is possible to easily and effectively slide the plate under pressure.

The plate-like body 17b made of wear-resistant ceramics has a coefficient of thermal expansion of 70XlO7/°C or less, and although it is thick and large, it has excellent thermal shock resistance and excellent durability.

Moreover, a composite plate 27 as shown in FIG. 9 and FIG.
．． It is effective to use 37 as an axial sealing plate.

In the example shown in FIG. 9, square prism-shaped wear-resistant ceramics 27b are fixed to both ends of the side wall of the thin metal plate 27a. 1st O
In the illustrated example, square prism-shaped wear-resistant ceramics 37b are fixed to both end surfaces of a metal wall-like body 37a. In either example, the wear-resistant ceramics 27b, 37b come into contact with the inner surface of the housing and slide, so unlike when the entire housing is molded with metal, the wear-resistant ceramic parts are less likely to wear out. The metal portion 27b is sandwiched between the ceramic portions.

Abrasion of 37b can also be prevented. Furthermore, from a manufacturing standpoint, it is easier to manufacture large-sized members from metal than from ceramics, so it becomes easier to manufacture the axial sealing plates 27, 37, especially when the rotor 2 has large dimensions.

Furthermore, in the same way as the radial sealing plate described above, it is also effective to prevent wear of the housing metal by installing a wear-resistant ceramic or glass lining layer on the inner surface of the housing and guiding the opposing axial sealing plate. .

Each structure of the axial sealing plate shown in FIGS. 8 to 1O described above can also be adopted as the structure of the diaphragm plate in the radial seal.

Next, the bypass sealing C (see FIG. 1) will be described.

Fig. 11 is a schematic diagram showing the vicinity of the rotor outer circumference of the air preheater;
FIG. 12 is an enlarged view of the main part of FIG. 11.

In this example, the present invention is applied to sealing between the outer peripheral edge of the rotor 2 and the rotor housing.

That is, the sealing bar 9 is fixed to the housing (the upper and lower edges in FIG. 11), and the sealing member 8 is held by the holder 10.

As shown in FIG.
a and a thin layer portion 8b. The base 8a is made of corrosion-resistant steel or ceramics with a coefficient of thermal expansion of 70X10-7/°C or less, and is similar to the diaphragm plate base 4a shown in FIG.
All the configurations mentioned above can be adopted. The thin layer portion 8b is a thin plate made of wear-resistant ceramics or inorganic glass, or is a thin layer formed by glass lining, and can employ all the structures described for the diaphragm plate thin plate 4b shown in FIG. 4.

With the sealing member 8 held by the holder IO, the spring 11 is brought into contact with the base 8a, the thin layer portion 8b is brought into contact with the sealing bar 9, and is slid while being pressed by the elasticity of the spring 11.

FIG. 14 is a perspective view showing another seal member 18, and FIG. 15 is a first perspective view showing the installation state of this seal member I8.
It is a figure similar to figure 2.

The overall shape of this seal member 18 is similar to that of the seal member 8, but a plurality of through holes 18a are provided so as to connect opposing side surfaces 18b and 18c. and,
By bringing one side surface 18c into contact with the sealing bar 9 and bringing the other side surface 18b into contact with the spring 11, air leakage through the through hole 18a is prevented. Seal member 1
The entire body 8 is made of wear-resistant ceramic having a coefficient of thermal expansion of 70×10 −7 /° C. or less.

According to the sealing member 18 of this example, in addition to the above-mentioned effects, the amount of expensive wear-resistant ceramics can be reduced by the amount of the through hole 18a, thereby reducing the weight and cost.

Moreover, instead of the above sealing members 8 and 18, FIGS.
A sealing member such as that shown in FIG. 20 can be used to reduce the amount of wear-resistant ceramic.

The sealing member 28 shown in FIG. 16 has a coefficient of thermal expansion of 70×1.
It is molded from wear-resistant ceramics with a temperature of 0-7/℃ or less, and has a U-shaped cross section. The back surface 28a comes into contact with the sealing bar and is slid under pressure, and the recess 28b side is pressed by the spring.

In the sealing member 38 shown in FIG. 17, a flat plate 38b made of wear-resistant ceramics is fixed to the back surface of a block 38a made of corrosion-resistant steel and having a U-shaped cross section. This plate 38b is pressed and slid against the sealing bar.

In the sealing member 48 shown in FIG. 18, a protrusion 48c is provided at the edge of a corrosion-resistant steel base 48a having a U-shaped cross section.
Recesses 48d are provided on both sides of the wear-resistant ceramic plate 48b, and the plate 48b is held by fitting the projections 48c into the recesses 48d. This plate 48b is slid under pressure against the sealing bar, and the base body 48a is pressed by a spring.

In the seal member 58 shown in FIGS. 19 and 20, rectangular holes are formed in several locations in the longitudinal direction on the upper surface of a corrosion-resistant steel base 58a having an R-shaped rectangular cross section (a rectangle with rounded corners). 2 to 3 holes) and insert the base 58 into these holes.
A wear-resistant ceramic 58b is disposed in a state slightly protruding from the upper surface of the base body 58a, the surface protruding from the upper surface of the base body 58a is used as a sliding surface, and all surfaces located below the hole are substantially made of corrosion-resistant steel 58a. The sealing member 58 is constructed by providing a wear-resistant ceramic 58b having a trapezoidal column shape and surrounded by 58c.

This sealing member 58 is pressed and slid against the sealing bar by a spring. The wear-resistant ceramic 58b is
Since it is entirely surrounded by corrosion-resistant steel except for the sliding surface side, it is more stable against thermal shocks caused by washing with water, etc. In this case, wear-resistant ceramics (for example, alumina) with a coefficient of thermal expansion greater than 70×10-'10C can also be used.

FIG. 21 is a broken perspective view showing another seal member 68;
FIG. 2 is an enlarged sectional view of the main part of FIG. 21.

In this example, there are several locations (for example, 3 to 4 locations) in the longitudinal direction on the base body 68a made of ceramics or corrosion-resistant steel and having a U-shaped cross section.
Attach the fixing piece (for example, made of SUS) 68b.

Specifically, the piece fixing bolt 68d is passed through the through hole 68f, and the fixing piece 68b is attached to a predetermined position.
Both ends of a trapezoidal plate 68c made of wear-resistant ceramics are fitted into the notches 70 provided in the fixing piece 68b, and the piece fixing bolt 68d is tightened to fix the piece 68b and plate 68c in the illustrated position. .

In this example, instead of providing the fixing pieces 68b at several locations in the longitudinal direction, two fixing pieces having approximately the same length as the base body 68a are fixed, and the entire length of the base body 68a in the longitudinal direction is It may be covered with a fixing piece, in which case the sealing performance is further improved. This example has the advantage that the wear-resistant ceramic plate (68c) that presses and slides against the sealing bar can be replaced at any time, or the base body 68a side can be replaced at any time.

Note that abrasion of the sealing bar can be effectively prevented by incorporating or fixing a thin plate made of wear-resistant ceramic on the surface of the sealing bar to serve as a ceramic guide on which the sealing member slides under pressure. Of course, acid-resistant enamel or glass lining may be applied to the surface of the sealing bar.

Furthermore, specific experimental examples will be explained.

A large ship falls on the ground The thermal shock resistance of each sample was measured under the following conditions.

Sample 100xloo x (thickness t)+am thickness t: 1. 2. 3. 5. 10. 100 temperature difference Constant temperature bath (170°C) held for 1 hour → Water (20°C)
Input, 150℃ difference evaluation Observe the presence or absence of crack generation by dyeing test ×... Yes ○... None Ceramics Silicon nitride, silicon carbide, alumina, porcelain A Porcelain B Porcelain C Porcelain porcelain E Mullite, Sialon, (86X 10-7/℃) (74X 10-7/'C) (70X 10-7/℃) (63X 10-7/℃) (58X 10-7/℃) Thermal shock resistance test results of zirconia table ceramics A thin plate of ceramic (1) shown in the table below and a plate of ceramic (2) were bonded together, and a thermal shock resistance test was conducted on each bonded sample.

Table 1 Results of face-to-face tree impact test of bonded samples Actual results Enamel treatment was applied to the corrosion-resistant steel as shown below, and a thermal shock resistance test, an abrasion resistance test, and a corrosion resistance test were conducted on each of them.

Sample base material Corrosion-resistant steel treatment Hollow treatment thickness 0.3n+m, 0.7mm, 1
．． 2m+++, (Comparison: No enamel treatment) Thermal shock test base material 100 x 100 x 3 mm Metal panel Temperature difference Constant temperature bath (I70°C) ■ Time holding → Underwater (20
°C) charging, 150°C difference evaluation Presence or absence of crack generation by dyeing test ○...No ×...Yes Wear resistance test base material 100φX3mm disk load 4 kg (50g/cm2) Testing machine
600φ disc, rotation speed 30 revolutions/min Evaluation Wear thickness (mm
°C Evaluation Observation of Corrosion Condition Table 3 A base material made of corrosion-resistant steel was used as a sliding surface, and a thin ceramic plate of the material and film thickness shown in the table below was bonded to the base material. Then, a thermal shock resistance test, a sliding surface wear resistance test, and a corrosion resistance test were conducted using the method of Experimental Example 2 for each.

The thermal shock resistance of alumina was measured under the following conditions, and it was confirmed that the thermal shock resistance was improved by enclosing it with heat-resistant steel.

Sample alumina (cross section: top bottom 100 mm, bottom bottom 70n+m
, height 20 mm and length 100 mm) No heat-resistant steel enclosure; Existing as is without enclosure; Enclose the entire body with heat-resistant steel 3 mm thick except for the bottom surface with a cross section of 70 mm Temperature difference Constant temperature chamber (170°C) 1 Time retention - water (2
0°C), 150°C difference evaluation Observe the presence or absence of cracks by dyeing test ×...Yes, ○...No Table 5 Thermal shock resistance test results of alumina We applied it to a preheater and confirmed its effectiveness.

The locations where the seal member is applied are as follows.

The contact area between the rotor outer circumference and the housing (Axial seal A: see Figure 1) ■The rotor outer circumference (Axial sealing plate 7) ■The inner surface of the housing The contact area between the rotor side surface and the bypass section of the housing (Bypass seal C) (Figure 11) ) ■Rotor side (sealing member 8) ■Housing sealing part 9 Contact area between diaphragm plate 4 and radial sealing plate 6 on rotor side (Fig. 1, Fig. 3, Fig. 4) ■Radial sealing plate 6 ■ Diaphragm Plate 4 Evaluation ○: Indicates a case where the seal young fruit is good and continuous operation without repair has exceeded a month.

×: Indicates a case where the sealing effect deteriorated within 24 months and the sealing member was replaced, or the sealing effect continued to be used in a state where the sealing effect decreased.

In the air preheater having sealing members as in Examples Nα1 to Nα6 of the present invention, since the sealing members are in close contact with each other, a good sealing effect can be obtained. The sealing member adheres tightly and maintains airtightness in a sliding state, but because one side of the sealing member has ceramic or enamel with excellent wear resistance bonded to the surface, it can be used for a long time and requires less maintenance. This has the advantage that the frequency can be reduced.

In addition, since the seal member is crimped, even if the rotor or housing is deformed due to heat, etc., the gap between the seal members is naturally reduced, and a close contact state can always be maintained.

On the other hand, in the conventional example Nα7, the metal seal member that presses and slides on the seal portion deteriorates in a relatively short period of time, and parts need to be replaced at the time of periodic inspection after one year. Also, conventional example N (
Since 18 is a conventional structural seal that does not slide by pressure, the sealing effect is reduced at locations where the rotor or housing is deformed due to heat.

(Effects of the Invention) According to the sealing member for a gas preheater according to the present invention, at least a portion of the sealing member is made of inorganic glass and/or wear-resistant ceramics, so corrosion caused by hot waste gas can be effectively prevented. It also improves wear resistance and maintains good sealing performance for a long period of time. In addition, since it is made of inorganic glass and/or wear-resistant ceramics with a small coefficient of thermal expansion, or all surfaces except the sliding surfaces are coated with corrosion-resistant steel, it has improved thermal shock resistance and a longer service life. ,
The frequency of maintenance can be reduced. Also,
It has become possible to pressurize and slide the sealing member for the air preheating crosspiece, and it has also become possible to always seal with the sealing member in close contact.

Thereby, the thermal efficiency of the gas preheater can be kept high for a long period of time.

[Brief explanation of the drawing]

Figure 1 is a schematic side view of the air preheater, Figure 2 is a schematic front view of the air preheater, Figure 3 is a perspective view of the radial sealing plate, and Figure 4 is a perspective view of the diaphragm plate (axial sealing plate). Figures 5 and 6 are front views showing other radial sealing plates, Figure 7 is a perspective view showing blocks for other radial sealing plates, and Figures 8, 9, and 10. are respectively a perspective view showing an example of an axial sealing plate, Fig. 11 is a schematic diagram showing the vicinity of the rotor periphery of the air preheater, Fig. 12 is an enlarged view of the main part of Fig. 11, and Figs. 13 and 14 are respectively FIG. 15 is a front view showing the state in which the seal member of FIG. 14 is attached; FIG. 16, FIG. 17, FIG. 18, FIG. 19, FIG. 21. 20 is a sectional view of FIG. 19, FIG. 22 is an enlarged view of the main part of FIG. 21, and FIG. 23 is a schematic perspective view of the air preheater. It is. 2...Rotor 4...Diaphragm plate 4a...Base 4b...Thin layer portion 6, 16.26.36...Radial sealing plate 6a, 16a, 26a, 36a - Base 6b
, 36b... Thin layer portion 7, 17.27.37... Axial sealing plate 8, 18.28.38.48.58.68...
・Sealing member 9 for bypass seal...Sealing bar A...Axial seal B...Radial seal C1...Bypass seal C by 1 inch in Figure 1 → then Figure 2 F'D-1- 4 4a (70) Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 17 Fig. 19 Fig. 20

Claims (1)

[Claims] 1. A sealing member for a gas preheater that seals a gap between the outer periphery of a rotor and a housing of a gas preheater or a gap between a side surface of the rotor and a radial sealing member, wherein the sealing member has thermal expansion. A sealing member for a gas preheater, characterized in that at least a portion thereof is formed of inorganic glass and/or wear-resistant ceramics having a coefficient of 70×10^-^7/°C or less. 2. The sealing member for the air preheater is a plate-shaped body made of inorganic glass and/or wear-resistant ceramics, and a plate-shaped body made of ceramics whose coefficient of thermal expansion is 70 × 10^-^7/℃ or less. 2. The sealing member for a gas preheater according to claim 1, wherein the sealing member is made of a material joined to a body. 3. The gas according to claim 1, wherein the sealing member for the air preheater is made of a plate-shaped body formed of inorganic glass and/or wear-resistant ceramics and a plate-shaped body formed of corrosion-resistant steel. Seal member for preheater. 4. The sealing member for a gas preheater according to claim 1, further comprising a recess or hollow portion that is not filled with inorganic glass or wear-resistant ceramic. 5. A sealing member for a gas preheater made of wear-resistant ceramics and corrosion-resistant steel, in which ceramic is used as a sliding surface and all other surfaces except for the sliding surface are substantially surrounded by corrosion-resistant steel.