JPH10176981A - Apparatus for testing wear of fluid bed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately estimate in a short time a wear line of a member set in a fluid bed, by rotating a test piece in the fluid bed simulating an actual machine end enabling an accelerated test. SOLUTION: A test piece 10 is set at a test piece-fitting part 12 and a fluid material is deposited on a porous plate 4. The air is supplied from a gas injection pipe 3 to form a fluid bed 5. A heating apparatus 6 is started to turn a temperature in a container to be equal to that of an actual machine. When a temperature of the fluid bed 5 approaches the temperature of the actual machine, a cooling water is supplied from a cooling water feed apparatus 17 to cool a returning waste water and circulate the waste water as the cooling water. The amount of the cooling water to the fed is set so that a temperature inside the test pipe 10 becomes the same as the temperature of the actual machine. When a test state is equal to a state of the actual machine, a motor 15 is driven to rotate a rotary shaft 11. A revolution number is wet to make an average peripheral velocity of the test piece 10 approximately 5-15 times a flow velocity in the fluid bed 5. Since the test piece 10 has a larger peripheral velocity than the flow velocity of the gas, an accelerated test reproducing a wear given rise to the actual machine can be realized in a shot time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluidized bed wear tester for testing the wear behavior of a heat transfer tube material or the like provided in a fluidized bed.

[0002]

2. Description of the Related Art A pressurized fluidized bed boiler in which coal is fluidly burned under pressure has a thermal efficiency of 40% or more by a combined cycle combined with a gas turbine, a high desulfurization rate in a furnace, and a low NOx generation amount. Due to its small number and other features, it is currently being developed as a new type of boiler that replaces conventional boilers.

In a pressurized fluidized-bed boiler, a boiler body has
The fluidized bed is composed of bed material composed of air, pulverized coal, coal ash, sand, etc., and the fluidized bed is provided with evaporators, superheaters, reheaters, etc. that generate steam. The generation of water vapor, overheating,
Reheating takes place. Each of such evaporators, superheaters, and reheaters is constituted by a heat transfer tube.

[0004]

Such a heat transfer tube wears due to contact with pulverized coal and bed material at a high temperature and at a considerable flow rate. Further, since a lower temperature steam flows at a higher speed in the inside than in the outside, a temperature difference is generated, which also affects the wear. For this reason, a device for testing the wear characteristics with the heat transfer tube used being almost the same as the use condition is required.
Japanese Utility Model Laid-Open No. 60-114944 discloses a fluidized bed abrasion test apparatus, but the temperature of the test piece is the same as the temperature of the bed material, and does not simulate the temperature of steam passing through the inside.
In addition, there is a problem that the test takes a long time because the accelerated test cannot be performed.

The present invention has been made in view of the above problems, and has as its object to provide a fluidized-bed abrasion test apparatus capable of realizing a temperature difference between the inside and outside of a test piece and capable of performing an acceleration test.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, a fluid agent discharge pipe is provided at an upper portion,
A container having a perforated plate at the lower part and a gas injection pipe from below the perforated plate, and a test piece having a vertical rotation axis in the container and having a test piece mounted substantially perpendicular to the rotation axis and rotating the test piece A rotating device; and a heating device provided around the container to heat the container.

A fluid material (bed material) is placed on a perforated plate,
A fluidized bed is generated in the container by injecting a gas from below with a gas injecting tube, and heated by a heating device to realize the same fluidized bed as the actual machine. By mounting the test piece substantially perpendicular to the rotation axis and rotating in the fluidized bed, wear is promoted and an accelerated test is possible.

According to the second aspect of the present invention, a cooling fluid supply device is provided in the rotating shaft so that the cooling fluid passes through the test piece and supplies the cooling fluid to the rotating shaft.

[0009] By passing the cooling fluid from the cooling fluid supply device through the cooling fluid path of the rotating shaft through the test piece, the internal temperature of the test piece can be made the same as that of the actual machine, and the temperature difference between the inside and outside of the test piece is realized. can do.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of the present invention. A fluid agent discharge pipe 2 is provided at the top of the container 1 and connected to a cyclone 7, and a gas injection pipe 3 is connected to a lower surface of the vessel 1 to supply gas from a gas supply device (not shown). A perforated plate 4 is provided at the bottom of the container, and the gas flowing from the gas injection pipe 3 is uniformly blown into the container, and the bed material (fluidizing agent) deposited on the upper surface is blown up to form the fluidized bed 5.

A heating device 6 is provided around the vessel 1 and heats the fluidized bed 5 in the vessel to the same temperature as the fluidized bed of an actual machine (a plant simulated by a test apparatus, for example, a pressurized fluidized bed boiler). . As the heating device 6, an electric heater or the like is used. The container 1 and the heating device 6 are covered with a casing 8 and insulated. A thermocouple 9 is provided inside the fluidized bed 5, and the heating device 6 controls the temperature of the fluidized bed 5 based on the measurement data.

A rotating shaft 11 is provided vertically through the top of the container 1 and has a test piece mounting portion 12 at the lower end.
0 is mounted horizontally. A pulley 13 is attached to an upper portion of the rotating shaft 11, and the rotating shaft 11 is rotated by a motor 15 via a belt 14. A rotary joint 16 is provided on the top of the rotating shaft 11.
Connected to the water supply channel 11a and the drain channel 11b provided in the
The cooling water from the cooling water supply device 17 is supplied to the water supply channel 11a, and the wastewater from the drainage channel 11b is returned to the cooling water supply device 17.

FIG. 2 shows a test piece mounting portion 12 at the lower end of the rotating shaft 11.
The details are shown below. A water supply channel 11a and a drainage channel 11b are provided in the rotating shaft 11. At the lower end of the rotating shaft 11, test piece mounting portions 12 are provided horizontally on the left and right, respectively. A tubular test piece 10 (test tube) such as a heat transfer tube is mounted on each test piece mounting portion 12, and fixed by bolts 12a. You. The outer end surface of the test tube 10 is closed so that cooling water passes through the inside.

Next, the operation will be described. First, as shown in FIG. 2, the test piece 10 is mounted on the test piece mounting portion 12, and a bed material is deposited on the perforated plate 4. The fluidized bed 5 is generated by supplying air from the gas injection pipe 3. Next, the heating device 6 is activated to make the temperature in the container 1 the same as the actual device. Also, the flow rate of air is set so that the flow rate in the container 1 is the same as that of the actual machine. When the temperature of the fluidized bed 5 approaches the actual machine, the cooling water is supplied from the cooling water supply device 17, and the drain water is cooled and circulated as cooling water. The supply amount of the cooling water is set so that the temperature inside the test piece 10 becomes equal to that of the actual device. The internal temperature of the test piece 10 can be estimated from the temperature of the return water.

When the test condition is the same as that of the actual machine, the motor 15 is started to rotate the rotating shaft 11. The number of rotations is such that the average peripheral speed of the test piece 10 is 5 to 5 of the flow velocity in the fluidized bed 5.
Set to about 15 times. Since the flow velocity of the gas in the fluidized bed 5 is usually about 1 m / sec, the peripheral velocity is 5 to 5 m / sec.
The rotation speed is set to be 15 m / sec. By setting the peripheral speed higher than the gas flow velocity in this way, it is possible to realize an accelerated test that reproduces the wear that occurs in the actual machine in a short time.

In the actual machine, the heat transfer tube is stationary and the fluidized bed flows, but in the test, the test piece 10 is perpendicular to the moving fluidized bed 5.
To move. The result of examining whether or not the test reproduces the wear in the actual machine due to such a difference will be described with reference to FIGS.

FIG. 3 is a view showing the actual state of the heat transfer tube used in the evaporator (evaporator) and the state of wear in the test apparatus of the present invention. (A) shows the state of wear in a pilot plant that is constructed prior to a commercial plant and performs various tests. The horizontal axis indicates the angle θ taken counterclockwise with the flow direction of the bed material taken as 0 ° as shown in (B). However, since the heat transfer tube is symmetric with respect to the flow of the bed material, wear is also symmetric. , It also represents a clockwise angle. The vertical axis represents the% of the sheet thickness reduced by abrasion with respect to the original sheet thickness.
It shows that the plate thickness becomes 0 at 00%. The material of the heat transfer tube is 1
Cr-0.5Mo steel. Abrasion occurs in the range of 30 to 120 degrees around 70 degrees.

FIG. 3B shows the result of a wear test on the same heat transfer tube using the wear test apparatus of the present invention. The figure shows test piece 10
And a broken line on the outer periphery indicates a state where it is not worn. The bed material flow direction is the one in which the test piece 10 is stationary and the bed material flows (the same expression as that of the actual machine). In addition,
In the apparatus shown in FIG. 1, the test piece 10 moves in the left and right direction by rotation, in this case to the right, and there is a flow of the fluidized bed 5 from the lower side to the upper side.
m / s, the relative velocity in the left-right direction is 5-15 m / s.
Since the test is performed at about s, the main flow direction is shown. To be precise, a vector display that combines the vertical and horizontal flows is preferable. The test results show that wear occurs around 70 to 80 degrees in both clockwise and counterclockwise angles.
It shows that the wear occurrence position and condition are extremely similar to those of the actual machine (pilot plant) shown in FIG.

FIG. 4 shows the wear results of the actual machine and the test piece 10 as in FIG. A heat transfer tube of a superheater (super heater) is used as an object. The material is 18Cr-10Ni-0.
8Nb. (A) shows the wear of the heat transfer tube of the pilot plant.
It decreases sharply toward 0 and 60 degrees. (B) shows a wear state of the test piece 10 in the present wear test apparatus.
The test piece 10 rotates toward the bed material flow direction. It wears largely at about 45 degrees clockwise and counterclockwise, and is very similar to the wear position shown in FIG.

FIGS. 3 and 4 show that the wear position of the heat transfer tube changes depending on the material, and the test results of the present wear test apparatus faithfully show this tendency. In this wear test apparatus, unlike the actual machine, the horizontal direction (rotation direction) of the test piece 10
The bed material is worn by the bed material from the vertical direction, which is the flow direction of the fluidized bed 5, and the vertical flow is small relative to the rotation direction, so the wear position and the wear amount are almost determined by the relative flow in the rotation direction. Thereby, an acceleration test can be performed by adjusting the rotation speed, and the test period can be significantly reduced. In addition, by supplying cooling water to the inside of the test piece 10, the temperature inside and outside the test piece 10 can be made the same as that of the actual device.

In the above-described embodiment, air is supplied from the gas injection pipe 3, but any other gas, for example, a stable gas such as nitrogen gas may be used. In addition, the test piece 10 is cooled by supplying cooling water from the cooling water supply device 17, but may be cooled using a stable gas such as air.

Using the present fluidized bed abrasion tester, using various bed materials, the flow velocity in the container 1, the rotation speed of the test piece 10, the hardness and particle size of the bed material, the material and hardness of the test piece 10, and the bed material The wear life of the heat transfer tube or the like can be predicted in a short period of time using the temperature, the temperature of the test piece 10 and the like as parameters.

[0023]

As is clear from the above description, according to the present invention, an accelerated test can be performed by rotating a test piece in a fluidized bed simulating an actual machine, and it can be installed in the fluidized bed in a short period of time. It is possible to accurately predict the wear life of a member such as a heat transfer tube. Further, by cooling the inside of the test piece, the temperature condition of the test piece can be made the same as that of the actual device.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a detailed view of a test piece mounting portion.

FIG. 3 is data showing the state of wear of an actual evaporator heat transfer tube (A) and a test piece (B).

FIG. 4 is data showing the abrasion state of an actual superheater heat transfer tube (A) and a test piece (B).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Fluid discharge pipe 3 Gas injection pipe 4 Perforated plate 5 Fluidized bed 6 Superheater 7 Cyclone 8 Casing 9 Thermocouple 10 Test piece 11 Rotation axis 12 Test piece mounting part 13 Pulley 14 Belt 15 Motor 16 Rotary joint 17 Cooling water Supply device

Claims (2)

[Claims] A container having a fluidizing agent discharge pipe in an upper part, a perforated plate in a lower part, and a gas injection pipe from below the perforated plate;
A test piece rotating device that has a vertical rotation axis in the container, attaches a test piece substantially perpendicular to the rotation axis, and rotates the test piece; a heating device provided around the container to heat the container; A fluidized bed abrasion test device comprising: 2. A cooling fluid supply device is provided in the rotating shaft, the cooling fluid is supplied to the rotating shaft so that the cooling fluid flows in a test piece. 2. The fluidized bed wear test apparatus according to 1.