CN103698163A - Equipment fixing device for chimney gas sampling representativeness verification test - Google Patents

Abstract

The invention relates to an equipment fixing device for a chimney gas sampling representativeness verification test. The equipment fixing device comprises a pitot tube sleeve vertically penetrating a chimney wall, wherein a pitot tube is sleeved in the pitot tube sleeve; a connecting tube is arranged outside the pitot tube sleeve and connected with a flange plate through a fixing bracket; the flange plate is fixedly connected to the chimney wall through a flange nozzle. The equipment fixing device is easy to implement, almost does not affect the original safety performance of a chimney body, and has the advantages of accuracy for measurement, simplicity and convenience for operation and the like.

Description

Equipment fixtures for representative verification tests of stack gas sampling

technical field

The invention relates to the design of an on-site verification test device for nuclear facilities, in particular to an equipment fixing device for a representative verification test of chimney gas sampling.

Background technique

In order to accurately judge the operating conditions of nuclear facilities and determine the impact of effluents released from nuclear facilities on the environment, obtaining representative samples of airborne effluents from nuclear facilities is one of the key elements. In 1999 and 2010, the American National Organization for Standardization and the International Organization for Standardization successively updated the standards for sampling representative quantitative requirements, that is, "Sampling and Monitoring of Release of Airborne Radioactive Materials in Chimneys and Pipelines of Nuclear Facilities" (ANSI/HPSN13. 1-1999) and "Sampling of Radioactive Substances in Chimneys and Ventilation Ducts of Nuclear Facilities" (ISO2889-2010), my country's nuclear power plant regulatory authorities have begun to pay attention to and gradually explore and require nuclear facilities to carry out airborne effluent sampling Representative test.

Sampling representative tests are carried out on chimneys or pipes of nuclear facilities. Due to the complex structure of chimneys or pipes, and the need to measure gas flow rate uniformity, cyclone angle, etc. at the same time, the technology is complicated. At present, only a few countries in Europe and the United States have mastered a complete set of technologies. . There are few developments and reserves of similar technologies in China.

When implementing on-site verification experiments of nuclear facilities, it is an important technical issue to install relevant testing instruments on the pipes or chimneys of nuclear facilities in a stable and reliable manner to measure various parameters.

Pitot tube is the key equipment for sampling representative verification test. It needs to be inserted into the flue during measurement. Different measurement environments should use different specifications of pitot tube, and its length can reach several meters. In order to obtain accurate measurement data, it is necessary to ensure that the pitot tube is positioned accurately, can remain stable inside the pipeline, reduces wind disturbance, and can rotate flexibly. The pitot tube has strong elasticity. If the traditional single fulcrum is used to fix the pitot tube, there will be a certain deflection of the pitot tube. There may be an offset between the measurement position and the preset point when the tube arm droops, which will lead to measurement inaccuracy, and at the same time make the pitot tube plugging and unplugging difficult. Greater resistance.

Contents of the invention

The object of the present invention is to aim at the defects of the prior art, provide a kind of equipment fixing device of chimney gas sampling representative verification test, reduce the adverse effect that single fulcrum fixing mode causes to test, thereby make nuclear facility chimney gas sampling representative test each It is more convenient and faster to read the angle in the determination of the characteristic parameters.

The technical scheme of the present invention is as follows: a device fixture for chimney gas sampling representative verification test, comprising a pitot tube sleeve vertically passing through the chimney wall, the pitot tube is sleeved in the pitot tube sleeve, and the pitot tube sleeve A connecting pipe is arranged outside, and the connecting pipe is connected to the flange plate through a fixed bracket, and the flange plate is fixedly connected to the chimney wall through a flange mouth.

Further, the equipment fixing device for the representative verification test of chimney gas sampling as described above, wherein the flange is provided with an angle scale for positioning the gas cyclone angle measurement test; the pitot tube sleeve is provided with There is a length scale for pitot tube positioning.

Further, the equipment fixing device for the representative verification test of chimney gas sampling as described above, wherein the fixing bracket is circular and fixed on the outer wall of the connecting pipe, and the fixing bracket is connected to the flange through bolts.

Further, the equipment fixture for representative verification test of chimney gas sampling as described above, wherein, one end of the flange nozzle is welded to the opening of the chimney wall, and the other end is connected to the flange plate through bolts.

Further, the above-mentioned equipment fixture for the representative verification test of chimney gas sampling, wherein, the end of the connecting pipe is provided with threads, and the pitot tube sleeve is covered with a fastening nut. When the measurement position of the pitot tube reaches the point After the position is required, the fastening nut and the thread at the end of the connecting pipe are screwed and fixed.

Further, in the device fixture for representative verification test of chimney gas sampling as described above, a fastening plug is provided outside the pitot tube, and the fastening plug is welded and fixed to the inner wall of the pitot tube sleeve.

Furthermore, in the equipment fixing device for the representative verification test of chimney gas sampling as described above, a supporting bearing is provided between the Pitot tube and the inner wall of the Pitot tube sleeve.

The beneficial effects of the present invention are as follows: the device provided by the present invention is used for the fixing of the test equipment in the representative verification test of the chimney gas sampling of nuclear facilities (such as nuclear power plants, etc.), and the design is passed through holes and welded flanges on the chimney of nuclear facilities The fixed device of the test equipment is connected in the same way, and no major changes are made to the original design of the chimney. After the experiment is completed, it is only necessary to weld the plug or install a blind flange to restore the performance index of the chimney, which is easy to implement and is safe for the original chimney body. Performance has little to no impact. The device has the advantages of accurate measurement and easy operation.

Description of drawings

Figure 1 is a schematic diagram of the structure of the equipment fixture for a representative verification test of stack gas sampling.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, the equipment fixture of the chimney gas sampling representative verification test provided by the present invention consists of a pitot tube sleeve 1, a fastening nut 3, a fastening plug 4, a connecting pipe 5, a fixed support 6, a bearing 7, The flange plate 8 and the flange mouth 9 are formed, the S-shaped pitot tube 2 is set in the pitot tube sleeve 1, the two ends are fixed, and the whole fixing device is affixed to the chimney wall 10 through the flange mouth 9.

Open a hole on the chimney wall 10 and weld the flange nozzle 9. The material of the flange nozzle 9 is the same as that of the chimney wall. The connecting straight pipe is 90° perpendicular to the air duct. The flange mouth 9 and the flange plate 8 are connected by 12 sets of bolts, and the angle scale is engraved on the flange plate 8 for the positioning of the gas cyclone angle θ measurement test.

Bolts are welded on the two concentric circles of the flange plate 8, and the flange plate 8 is the connecting part of the flange mouth of the chimney and the pitot tube fixing bracket 6. During the test, the Pitot tube sleeve 1 and the fixing bracket 6 are directly set on the flange group; after the test is completed, the blind flange can be directly installed on the flange.

A fastening plug 4 is arranged outside the pitot tube 2, and the pitot tube is welded in the cylindrical stainless steel pitot tube sleeve 1 through the fastening plug 4 to enhance the strength of the pitot tube. Also be provided with the bearing 7 that plays a supporting role between. A stainless steel connecting pipe 5 is provided outside the Pitot tube sleeve 1, and the fixing effect on the Pitot tube is enhanced by extending the clamping length of the connecting pipe 5, so as to prevent possible left-right or up-down deflection and tremor during the test. The fixed bracket 6 is circular and fixed on the outer wall of the connecting pipe 5, and the fixed bracket 6 is connected with the flange 8 through bolts. Threads are designed at the end of the connecting pipe 5, the fastening nut 3 is installed on the Pitot tube sleeve 1, the Pitot tube sleeve 1 is inserted into the connecting pipe 5, and the Pitot tube sleeve 1 is provided with a length for the positioning of the Pitot tube scale, after adjusting the measuring position of the pitot tube to reach the required point, the fastening nut 3 can be tightened to fix the pitot tube.

During verification tests of chimney gas sampling flow uniformity in nuclear facilities, the use of equipment fixtures is as follows:

There is a scale on the cylindrical pitot tube sleeve for precise positioning of the test. Positioning can be achieved by:

(1) Plug-in type - Let the total length of the fixing device and the flange be L1, the length of the flange mouth be L2, the wall thickness of the chimney be L3, and the horizontal distance between a point to be measured and the inner wall of the chimney be L4. When inserting into the chimney, the scale value corresponding to the edge of the fixing device is L, then L=L1+L2+L3+L4.

(2) Pull-out type--Assume that the pitot tube is inserted into the chimney until it reaches the opposite side. At this time, the scale value of the sleeve corresponding to the edge of the fixing device is L1, and the horizontal distance between a certain point to be measured and the inner wall of the chimney is L2. When the pitot tube is inserted into the chimney, the scale value corresponding to the edge of the fixture is L=L1+L2.

During the cyclone angle verification test of chimney gas sampling in nuclear facilities, the use of equipment fixtures is as follows:

Assemble the measuring device, hang the fixing device on the bolt of the flange through the connecting tube turntable, and screw the nut to the position where the connecting tube can be relatively fixed and can be rotated flexibly. Turn freely. First adjust the vertical position of the Pitot tube to coincide with the vertical engraved line on the holding device, and then the extension line of the vertical engraved line corresponds to the scale on the flange as the 0° reference point. In the test, directly use the method corresponding to the engraved line on the holding device The clockwise and counterclockwise angles of the blue pan are used as measured values.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (8)

1. An equipment fixture for a representative verification test of chimney gas sampling, characterized in that: it includes a pitot tube sleeve (1) that passes vertically through the chimney wall (10), and the pitot tube (2) is set on the pitot tube sleeve ( 1), the pitot tube sleeve (1) is provided with a connecting pipe (5), and the connecting pipe (5) is connected to the flange (8) through the fixing bracket (6), and the flange ( 8) It is fixed on the chimney wall (10) through the flange mouth (9). 2. The equipment fixing device for the representative verification test of chimney gas sampling according to claim 1, characterized in that: the flange (8) is provided with an angle scale for the positioning of the gas cyclone angle measurement test. 3. The equipment fixture for the representative verification test of chimney gas sampling according to claim 1, characterized in that: the pitot tube sleeve (1) is provided with a length scale for positioning the pitot tube. 4. The equipment fixing device for the representative verification test of chimney gas sampling according to claim 1, characterized in that: the fixing bracket (6) is circular and fixed on the outer wall of the connecting pipe (5), The fixing bracket (6) is connected with the flange (8) by bolts. 5. The equipment fixture for representative verification test of chimney gas sampling according to claim 1 or 4, characterized in that: one end of the flange mouth (9) is welded to the opening of the chimney wall (10), The other end is connected with the flange (8) by bolts. 6. The equipment fixing device for the representative verification test of chimney gas sampling according to claim 1 or 2, characterized in that: the end of the connecting pipe (5) is provided with a thread, and the pitot tube sleeve (1) is covered There is a fastening nut (3), when the measurement position of the pitot tube reaches the point requirement, the fastening nut (3) and the thread at the end of the connecting pipe (5) are screwed and fixed. 7. The equipment fixture for the representative verification test of chimney gas sampling according to claim 1, characterized in that: the pitot tube (2) is provided with a fastening plug (4), and the fastening plug (4) is connected with The inner wall of the pitot tube sleeve (1) is fixed by welding. 8. The equipment fixing device for representative verification test of chimney gas sampling according to claim 1 or 7, characterized in that: between the pitot tube (2) and the inner wall of the pitot tube sleeve (1) There are supporting bearings (7).