Testing device for axial flow fan of nuclear power cooling tower

Abstract

The utility model relates to a nuclear power cooling tower axial flow fan testing device, which is characterized in that a testing air duct is formed by sequentially connecting a conical inlet group, a rectification grid section air duct group, a transition section straight pipe section, a pressure testing section and a cooling tower axial flow fan testing pipe, and the rectification grid section air duct group is provided with a #-shaped partition plate type rectification grid; the pressure measuring section is equipped with a sensor for measuring air volume, air pressure and other parameters. A movable supporting device is further arranged. The device integrates test functions of rotating speed, vibration, temperature rise and the like, realizes automatic data acquisition and analysis, solves the problems of difficult installation, unreliable data and the like in a large fan test, remarkably improves test efficiency and accuracy, and reduces labor cost and potential safety hazards.

Description

Technical Field

[0001] This utility model belongs to the fields of nuclear power technology and mechanical engineering technology, and relates to a testing device for axial flow fans of nuclear power cooling towers. Background Technology

[0002] Due to the environmental temperature control requirements of the Additional Cooling System (ECS) building in nuclear power plants, cooling tower fan components need to be installed in specific areas of the unit's cooling tower. The axial flow fans of nuclear power cooling towers are large in size and require seismic resistance, making existing testing devices difficult to install and fix, and their structures are simple. Furthermore, the testing device needs to meet specific requirements during the performance testing of nuclear power cooling tower axial flow fans, including measurable airflow, air pressure, vibration, bearing temperature rise, and ease of installation. Therefore, it is necessary to design a cooling tower axial flow fan testing device that is easy to install and test, and integrates the testing of performance parameters such as airflow, air pressure, vibration, bearing temperature rise, and fan efficiency.

[0003] The axial flow fans in nuclear power plant cooling towers are typically three meters in height and width. These fans require features such as earthquake resistance, intelligent control cabinet operation, and forced air exchange. Therefore, during factory performance testing of airflow, air pressure, vibration, and bearing temperature rise, issues related to installation, fixation, and integrated testing must be considered. Currently, bearing temperature rise and vibration tests are usually conducted manually using temperature guns and vibration meters at set intervals. This method suffers from inconsistent measurement locations, leading to unreliable data. Furthermore, the large size of the axial flow fans necessitates higher positions for testing, increasing the risk of accidents during the process.

[0004] The utility model patent with announcement number CN203743033U discloses a performance testing device for a nuclear power plant top fan. It mainly includes a duct system composed of a conical air inlet section, a rectifier grid, a transition section, and a pressure measuring section. It is fixed to a cement foundation with expansion bolts and equipped with vibration sensors and temperature monitoring units. It achieves simultaneous detection of air volume, air pressure, vibration, and temperature rise through an integrated testing system. However, it has limitations in terms of structural size and load-bearing capacity. This utility model solves the installation problem of ultra-large fans through a segmented expandable duct structure and a heavy-duty mobile support device, and is suitable for most fan performance testing conditions. Summary of the Invention

[0005] To achieve the above objectives, this utility model provides a nuclear power cooling tower axial flow fan testing device, which solves the problems of difficult installation and fixing, simple structure, and complicated testing operation of existing axial flow fan testing devices.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is a testing device for axial flow fans of nuclear power cooling towers, including a testing duct. The leftmost end of the testing duct is a conical inlet group, the right end of the conical inlet group is connected to a rectifier grid section duct group, the right end of the rectifier grid section duct group is connected to a transition section straight pipe section, the right end of the transition section straight pipe section is connected to a pressure measuring section, and the right end of the pressure measuring section is connected to a testing pipe for the axial flow fans of the cooling tower.

[0007] Furthermore, the rectifier grid section air duct assembly is equipped with a "well"-shaped baffle rectifier grid.

[0008] Furthermore, each of the test air ducts is equipped with a support device at its bottom. The support device is a movable bracket and is equipped with casters at its bottom.

[0009] Furthermore, a fan base is provided below the test pipe for the cooling tower axial fan, the cooling tower axial fan is placed on the fan base, and the cooling tower axial fan is fixed to the fan base by screws.

[0010] Furthermore, a base plate is welded to the bottom of the fan base. When installing the testing device of this utility model, an expansion bolt fixing plate can be set on the ground and fixed to the cement foundation by expansion bolts. A pad can be set between the base plate and the expansion bolt fixing plate, and the pad, the base plate and the expansion bolt fixing plate are fixed together by a screw with a nut. A washer is also set on the top of the base plate.

[0011] The beneficial effects of this utility model are:

[0012] 1. This utility model effectively solves the problem of difficult installation and fixation of large-volume cooling tower axial flow fan testing devices, greatly improves the installation efficiency of cooling tower axial flow fans and test air ducts, and reduces labor costs.

[0013] 2. This utility model combines testing elements such as speed, vibration, temperature, and noise with a fan performance testing unit. The automated control system can customize the testing interval and number of tests according to testing requirements, making it suitable for most fan performance testing conditions.

[0014] 3. This utility model eliminates the need for manual climbing to test the performance of large wind turbines, reducing safety hazards during testing and minimizing the impact of human error.

[0015] 4. This utility model can measure the input power and air volume through the fan performance testing unit, and calculate the efficiency of the fan through air pressure, which greatly improves the efficiency and accuracy of the performance testing of axial flow fans in nuclear power cooling towers. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a structural diagram of the present invention.

[0018] Figure 2 This utility model relates to a fan start-up unit and a testing unit.

[0019] Figure 3 This is an enlarged view of section I of the structural diagram of this utility model.

[0020] In the diagram, 1. Conical inlet assembly, 2. Rectifier grid section air duct assembly, 3. Transition section straight pipe section, 4. Pressure testing section, 5. Cooling tower axial flow fan test pipe, 6. Cooling tower axial flow fan, 7. Support device, 8. Fan base, 9. Fan start-up unit, 10. Fan performance testing unit, 11. Screw, 12. Washer, 13. Base plate, 14. Pad plate, 15. Expansion bolt, 16. Expansion bolt fixing plate. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example

[0022] like Figures 1-3 As shown, an embodiment of this utility model provides a testing device for an axial flow fan in a nuclear power plant cooling tower, including a test air duct.

[0023] The leftmost end of the test duct is a conical inlet group 1. The right end of the conical inlet group 1 is connected to a rectifier grid section duct group 2. The right end of the rectifier grid section duct group 2 is connected to a transition section straight pipe section 3. The right end of the transition section straight pipe section 3 is connected to a pressure measuring section 4. The right end of the pressure measuring section 4 is connected to a cooling tower axial flow fan test pipe 5.

[0024] The conical inlet assembly 1 ensures that the fan can draw in air from a fixed inlet, which helps control the air intake conditions. The conical design guides the airflow smoothly into the duct. This invention also adds a metal sieve plate at the rear end of the conical inlet assembly 1. By stacking throttles of different orifice sizes, the air intake volume is adjusted in layers. Compared with the conventional C-type test device that uses manual methods to adjust the air intake volume, this invention enables automatic adjustment of the air intake volume, and is more precise and reliable.

[0025] The rectifier grid section air duct assembly 2 is equipped with a "well"-shaped baffle rectifier grid, which can reduce turbulence during the air intake process and avoid measurement errors by physically separating the airflow.

[0026] The transition section 3 ensures sufficient airflow development and a stable transition, avoiding flow field distortion caused by abrupt changes in cross-section or pipe bending. Compared with the C-type test device, the transition section 3 of this invention is equipped with temperature and humidity sensors, which can monitor and correct test data in real time to ensure that the results meet standard operating conditions.

[0027] The pressure measuring section 4 is equipped with a static pressure hole and a pressure measuring hole, and sensors for measuring parameters such as air volume, air pressure, and power are installed on the outside of the pressure measuring section 4. The required parameters can be measured through the static pressure hole and the pressure measuring hole. Compared with the C-type test device, the pressure measuring section 4 of this utility model is also equipped with a universal signal input inspection instrument, which can simultaneously display parameters such as flow rate, temperature, and differential pressure, and realize automatic data recording and analysis through the host computer of the fan performance test unit 10.

[0028] The cooling tower axial fan test pipe 5 connects the test pipeline to the test fan, ensuring smooth air discharge through the fan. This invention utilizes technologies such as frequency converters and temperature controllers to achieve automatic adjustment of test parameters and data acquisition, reducing manual intervention.

[0029] Each test air duct is equipped with a support device 7 at its base. This support device 7 is a movable bracket, and each is fitted with casters. The support device 7 supports the test air duct, and the casters facilitate its movement. The position and number of the support devices 7 can be adjusted according to specific needs. Each support device 7 also features a foot-operated hydraulic system, allowing for height adjustment and locking by foot, improving the efficiency of alignment during air duct connection to the fan.

[0030] Below the test pipe 5 for the cooling tower axial flow fan is a fan base 8. During the test, the cooling tower axial flow fan 6 is placed on the fan base 8 and fixed on the fan base 8 by the screw 11, and then the fan performance is tested.

[0031] The bottom of the fan base 8 is welded with a base plate 13. When installing the testing device of this utility model, an expansion bolt fixing plate 16 can be set on the ground, and the expansion bolt fixing plate 16 can be fixed to the cement foundation by expansion bolts 15. A pad 14 can be set between the base plate 13 and the expansion bolt fixing plate 16. The pad 14 is a thin plate, and the number used can be adjusted according to the actual gap to ensure the stable fixing of the fan base 8. The pad 14, the base plate 13, and the expansion bolt fixing plate 16 are fixed together by a screw 11 with a nut. A washer 12 is also set on the top of the base plate 13. The washer 12 can increase the contact area between the nut on the screw 11 and the base plate 13, reducing the stress concentration between the nut and the base plate 13. The expansion bolt fixing plate 16 mainly serves as a connecting transition, which can increase the adjustment margin during the installation process.

[0032] This invention relates to an integrated performance testing device, employing a detachable mounting base and equipped with a fan starting unit 9 and a fan performance testing unit 10. The fan starting unit 9 is a frequency converter cabinet, primarily used for frequency conversion starting of motors with high power. The fan performance testing unit 10 consists of a testing host, flow meter, tachometer, pressure transmitter, etc. The detachable mounting base of this invention significantly reduces the difficulty and cost of connecting and installing axial flow fans of nuclear power cooling towers with test pipelines, and facilitates disassembly during the testing process of axial flow fans in nuclear power cooling towers.

[0033] This utility model adopts a transition installation structure, and the installation steps are as follows:

[0034] a. The conical inlet group 1, the rectifier grid section duct group 2, the transition section straight pipe section 3, the pressure measuring section 4, and the cooling tower axial flow fan test pipe 5 of the test duct are initially connected in sequence and placed on the support device 7 for docking and installation with the cooling tower axial flow fan 6. The support device 7 is equipped with four casters, which can realize the adjustment of the duct position during the docking process.

[0035] b. Install and assemble the cooling tower axial flow fan 6 with the fan base 8;

[0036] c. Hoist the test air duct and the axial flow fan 6 of the nuclear power cooling tower and connect them with fasteners. Use expansion bolts 15 and screws 11 to fix the axial flow fan 6 of the nuclear power cooling tower to the installation position. Determine the position of the expansion bolts 15, drill the expansion bolt holes, fix the expansion bolt fixing plate 16 of the fan base 8 to the concrete ground with the expansion bolts 15, loosen the nut of the screw 11 and adjust the thickness of the shim 14 so that the center of the cooling tower axial flow fan 6 is aligned with the center axis of the cooling tower axial flow fan test pipe 5, tighten the nut of the screw 11, and the installation is completed.

[0037] The steps for performance testing are as follows:

[0038] a. The speed, vibration, temperature and noise testing components are magnetically fixed to the inner wall of the air duct;

[0039] b. Connect the conical inlet assembly 1 and the pressure testing section 4 to the fan performance testing unit 10 via a high-pressure hose;

[0040] c. The fan is started by frequency conversion using the fan starting unit 9, and the fan performance such as air volume, air pressure, vibration, bearing temperature rise and fan efficiency are tested by the fan performance testing unit 10.

[0041] This utility model's nuclear power plant cooling tower axial flow fan performance testing device adopts a detachable mounting base, which easily enables the docking and installation of large nuclear power plant cooling tower axial flow fans with test ducts, significantly reducing testing labor costs. After the fan starts running, the fan performance testing unit monitors the speed, airflow, and air pressure of the nuclear power plant cooling tower axial flow fan in real time, while recording the vibration of the front and rear bearing positions, bearing temperature rise, and noise every 5 minutes. By using a variable frequency drive to start the cooling tower fan with a fan starting unit, the safety protection function of the nuclear power plant cooling tower axial flow fan is ensured, and the safety hazards to the national power grid are reduced. The fan efficiency can be calculated by measuring the fan's input power, airflow, and air pressure. Compared with traditional performance testing devices, this integrated testing mechanism of the nuclear power plant cooling tower axial flow fan performance testing device greatly improves performance testing efficiency and accuracy, and reduces the impact of human error, fully meeting the performance testing requirements of axial flow fans for nuclear power plant cooling towers.

[0042] This utility model patented technology for nuclear power cooling tower axial flow fan performance testing device has excellent characteristics such as convenient installation, easy real-time monitoring and timed testing, high performance testing efficiency and high testing accuracy. It will gradually replace the traditional fan testing system and form a dedicated device for nuclear power cooling tower axial flow fan performance testing.

[0043] The various embodiments in this specification are described in a related manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0044] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model are included within the scope of protection of this utility model.

Claims

1. A nuclear power cooling tower axial flow fan testing apparatus characterized by, The test duct includes a test duct, the leftmost end of which is a conical inlet group (1), the right end of which is connected to a rectifier grid section duct group (2), the right end of which is connected to a transition section straight pipe section (3), the right end of which is connected to a pressure measuring section (4), and the right end of which is connected to a cooling tower axial flow fan test pipe (5).

2. A nuclear power cooling tower axial fan testing apparatus as claimed in claim 1, wherein, The rectifier grid section air duct assembly (2) is equipped with a "well" shaped baffle rectifier grid.

3. A test device for a nuclear power cooling tower axial fan according to claim 1, characterized in that, Each of the test air ducts is provided with a support device (7) at its bottom. The support device (7) is a movable bracket and is provided with casters at its bottom.

4. A nuclear power cooling tower axial fan testing apparatus as claimed in claim 1, wherein, Below the test tube (5) for the cooling tower axial fan, there is a fan base (8). The cooling tower axial fan (6) is placed on the fan base (8) and fixed on the fan base (8) by screws (11).

5. A nuclear power cooling tower axial fan testing apparatus as claimed in claim 4, wherein, The bottom of the fan base (8) is welded with a base plate (13), and an expansion bolt fixing plate (16) is set on the ground. The expansion bolt fixing plate (16) is fixed to the cement foundation by expansion bolts (15). A pad (14) is set between the base plate (13) and the expansion bolt fixing plate (16). The pad (14), the base plate (13), and the expansion bolt fixing plate (16) are fixed together by a screw (11) with a nut. A washer (12) is also set above the base plate (13).

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