JPS5984090A - Rotary type heat exchanger - Google Patents

Abstract

PURPOSE:To prevent the progress of oxidization and improve seal properties by a method wherein oxidation resistant solid lubricating material fine powder is impregnated into the sprayed layer of ceramic of the sliding layer of a seal device. CONSTITUTION:First path 9, passing high-pressure suction air, and the second path 10, passing low-pressure exhaust gas, are formed in a housing 6 so as to cross a heat accumulating body 5 respectively. A ring gear 7 on the outer periphery of the heat accumulating body 5 and a drive gear 8 are engaged and the heat accumulating body 5 rotates in the housing 6 by receiving the driving force of a motor. The seal device 11 consists of a sliding part 11a, contacted slidingly with the heat accumulating body 5, and a spring member 11b. The sliding part 11a consists of a metallic plate 12 of stainless steel series and a sliding layer 13. At first, the ceramic is sprayed by means of plasma spray coating onto the metallic plate 12 of stainless steel series to make the ceramic spray coating layer 14. This ceramic spray coating layer 14 is porous, therefore, the oxidization is progressed into the spray coating layer and, accordingly, the oxidation resistant solid lubricating material fine powder 15 is impregnated in order to fill up the holes and, then, the layer is dried under a temperature higher than 100 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary heat exchanger, and is effective for use, for example, in a gas turbine heat exchanger that exchanges heat between compressed air and exhaust gas.

In conventional rotary heat exchangers, the sliding part of the seal device that partitions the low-pressure exhaust gas passage and the same-pressure air passage has been made of a stainless steel metal plate that is plasma-sprayed with ceramic. However, while this sealing device was in use, since the ceramic sprayed layer on the sliding part was porous, oxidation progressed to the inside, causing a volume change. As a result, distortion occurred in the ceramic sprayed layer, reducing sealing performance.

The present invention was invented in view of the above-mentioned drawbacks, and an object of the present invention is to improve the sealing performance of a sealing device by preventing oxidation inside a ceramic sprayed layer and eliminating +l:L distortion.

In order to achieve this objective, the present invention impregnates the ceramic sprayed layer with oxidation-resistant solid lubricant +1 fine powder, and fills the pores generated in the ceramic sprayed layer with this solid lubricant fine powder. This is to prevent the progression of

Next, one embodiment of the present invention will be explained with reference to the drawings.

In a gas star engine, as shown in FIG. 1, intake air is compressed by a compressor 2 driven by a turbine 1 and is drawn into a combustion chamber 3 at a high pressure. and,
In order to increase the efficiency of the engine, a rotary heat exchanger 4 exchanges heat between high temperature exhaust gas and low temperature intake air.

In the rotary heat exchanger 4, as shown in FIG. A ring gear 7 is disposed around the outer periphery of the heat storage body 5. A drive gear 8 meshes with the ring gear 7, and the heat storage body 5 rotates within the housing 6 under the driving force of a motor (not shown). Housing 6
A first passage 9 through which high-pressure intake air does not pass and a second passage IO through which low-pressure exhaust gas does not pass are formed across the heat storage body 5 in the first passage 1, respectively.

Therefore, when the high-temperature, low-pressure exhaust gas passes through the heat storage body 5, heat is absorbed by the heat storage body 5, and the exhaust gas becomes low-temperature and low-pressure and is led out to the second exhaust passage 10. On the other hand, the heat storage body 5 becomes high temperature by absorbing the heat of this exhaust gas,
Then, it receives the driving force of the driving gear 8 and rotates toward the first passage 9 side. Therefore, the high temperature heat storage body 5 is positioned across the first passage 9, and the low temperature and high pressure intake air receives heat from the heat storage body 5 and becomes high temperature and high pressure and is led out to the first passage 9 for intake air. That is, as the heat storage body 5 rotates, heat is exchanged between the high temperature exhaust gas and the low 11V intake air, and the exhaust gas is led out at a low temperature and the intake air at a high temperature. Furthermore, the sealing device 11 prevents high pressure air from leaking into the low pressure exhaust gas. This sealing device 11 is
It is formed by a sliding part 11a that comes into sliding contact with the thermal rest body, and a spring member 11b that presses this sliding part 11a toward the heat storage body 5 side.

Next, the second sliding portion tta will be explained in detail.

Stainless steel metal plate 1 with sliding part 11a on the ladder (not shown in Figure 3)
2 and a sliding layer 13. In order to form the sliding layer 3, ceramic is first plasma-sprayed onto the stainless steel metal plate 12. In other words, high DC power (5 (j
OA, 80v) was introduced and an intense electric arc was generated inside the gun. By flowing an inert gas such as nitrogen or hydrogen into the gun in this state, the C1 arc excites the gas and a thermal plasma of 16,000°C is generated, and the gas velocity becomes over 3000rn/s. . When ceramic powder particles are fed into this gun, the ceramic powder particles are melted by a flame of thermal plasma, and the flight speed of the melted particles is 600 m/s 9 or more. Soshi'C
When the gun is used to spray ceramic powder particles onto the stainless steel metal plate 12, intergranular viscosity occurs on the surface, forming a ceramic sprayed layer 14. Since this ceramic sprayed layer 14 is porous, oxidation progresses to the inside of the sprayed layer.Next, in order to close these pores, oxidation-resistant fixed lubricant fine powder is added.
5 (e.g. BN, N1p).

This impregnation is carried out by first adding the helical sprayed layer 14 into an aqueous solution in which solid lubricant fine powder 15 having a size of 108 m or less is suspended.
Immerse the sliding part ita that has been formed. Then, in this state, drying is performed to infiltrate the solid lubricant fine powder 15 into the ceramic sprayed layer 14 and close the pores of the ceramic sprayed layer 14. After that, drying is completed at a temperature of 100° C. or higher.

The sliding portion 11a is formed as described above.

According to experiments conducted by the present inventors, it has been confirmed that oxidation of the ceramic sprayed layer 14 can be prevented up to 900° C. or higher by impregnation with BNN fine powder. Furthermore, it has been confirmed that the antioxidant effect is improved by adding a phosphate-based inorganic adhesive to the aqueous solution used during impregnation.

Further, in this embodiment, the solid lubricant fine powder 15 is packed by impregnating the ceramic sprayed layer 14, but the solid lubricant fine powder 15 can also be packed by press-fitting into the ceramic sprayed layer 14 using high-pressure gas.

In the sliding part 11a of the heat exchanger of the present invention as described above, it is possible to prevent oxidation to the inside of the ceramic sprayed M14, reduce distortion of the sliding layer 13, and prevent deterioration of sealing performance. can do. Moreover, the sliding layer 13 has a heat storage resistance 5 of I? Even if it becomes thin due to abrasion, the anti-oxidation effect does not decrease.

Furthermore, the sliding properties of the sliding portion 11a deteriorated at high temperatures in the past, but in the present invention, by using the solid lubricant 11 powder 15 with 1JIW properties, the sliding properties are good even at high temperatures.

[Brief explanation of the drawing]

Figure ff11 shows an example of the use of the heat exchanger of the present invention.
FIG. 2 is a sectional view showing the heat exchanger shown in FIG. 1, and FIG. 3 is an enlarged t1 view of the main part of FIG. 5... Heat storage body, 7... Ring gear, 8... Drive gear. 9...! '61 Passage, 10...2nd ii
Tl path, 11... Seal device, 13... Sliding layer, 14... Ceramic sprayed layer, 15... Solid lubricant fine powder. Representative Patent Attorney Takashi Okabe Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] a disc-shaped heat storage body that rotates across a first passage and a second passage; a sealing device that is in sliding contact with a side wall of the heat storage body and partitions the first passage and the second passage; and a sealing device that partitions the first passage and the second passage; The sealing device includes a ring gear arranged therein and a drive gear that meshes with the ring gear, and the sliding layer of the sealing device is composed of a ceramic sprayed layer and solid lubricant fine powder contained in the ceramic sprayed layer. A rotary heat exchanger.