CN213632796U - Readable formula of bleed flow prevents blockking up buggy constant speed sampling system - Google Patents
Readable formula of bleed flow prevents blockking up buggy constant speed sampling system Download PDFInfo
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- CN213632796U CN213632796U CN202021842759.1U CN202021842759U CN213632796U CN 213632796 U CN213632796 U CN 213632796U CN 202021842759 U CN202021842759 U CN 202021842759U CN 213632796 U CN213632796 U CN 213632796U
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- 238000005070 sampling Methods 0.000 title claims abstract description 68
- 239000003245 coal Substances 0.000 claims abstract description 64
- 239000000843 powder Substances 0.000 claims abstract description 38
- 230000003068 static effect Effects 0.000 claims description 48
- 230000005540 biological transmission Effects 0.000 claims description 39
- 238000000605 extraction Methods 0.000 claims description 20
- 238000009530 blood pressure measurement Methods 0.000 claims description 13
- 239000002817 coal dust Substances 0.000 claims 2
- 238000005259 measurement Methods 0.000 abstract description 9
- 238000010298 pulverizing process Methods 0.000 abstract description 4
- 238000012360 testing method Methods 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 5
- 238000005086 pumping Methods 0.000 description 4
- 230000008021 deposition Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 230000000740 bleeding effect Effects 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
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Abstract
The utility model discloses a readable anti-clogging coal powder constant speed sampling system for the air exhaust flow, which belongs to the field of test and measurement of a pulverizing system, and comprises a coal powder sampling gun, an air speed measuring instrument, a primary coal powder separator, a secondary coal powder separator, an air exhaust flowmeter, a valve, an air exhaust fan, a first through flow flowmeter, a first through flow pipeline, a fourth through flow pipeline, a second through flow flowmeter, a second through flow pipeline, a third through flow pipeline and a through flow fan; owing to adopted through-flow medium and the readable measures such as bleed flow, the utility model discloses can thoroughly solve present sampling device pressure measuring hole and easily block up and the wayward problem of sampling state.
Description
Technical Field
The utility model relates to a readable formula of bleed flow prevents blockking up buggy constant speed sampling system belongs to the experimental measurement field of powder process system.
Background
The coal-fired power plant boiler is basically a pulverized coal boiler, the pulverizing system is an important auxiliary device of the boiler, and the operational safety and the economical efficiency of the boiler are closely related to the operational parameters of the pulverizing system. An important parameter for evaluating the coal pulverizing system is the fineness and uniformity index of the coal powder, so that how to perform constant-speed sampling to obtain qualified coal powder for assay and analysis is extremely important.
The pressure measuring hole is easy to block in the using process of an instrument adopted by the current national standard, no effective means is provided for judging whether the pressure measuring hole is blocked or not in the sampling process, whether the sampling is normal or not can be judged according to the number of the samples according to experience only after the sampling is finished, and abnormal re-updating is judged for sampling, so that the test working efficiency is low and the accuracy is not high.
Based on the reasons, in order to effectively solve the problems that the pressure measuring hole of the measuring device is easy to block and whether the sampling state is normal or not cannot be judged, a new coal powder constant-speed sampling system needs to be developed.
SUMMERY OF THE UTILITY MODEL
The utility model relates to a thoroughly solve the problem that measuring device easily blockked up and the sampling state is wayward, and the readable formula of the flow of bleeding prevents stifled type buggy constant speed sampling system that provides.
The utility model provides a technical scheme that above-mentioned problem adopted is: an extraction flow readable anti-blocking coal powder constant-speed sampling system is characterized by comprising a coal powder sampling gun, a wind speed measuring instrument, a primary coal powder separator, a secondary coal powder separator, an extraction flow meter, a first valve, an extraction fan, a first through flow meter, a first through flow pipeline, a fourth through flow pipeline, a second through flow meter, a second through flow pipeline, a third through flow pipeline and a through flow fan; the through-flow fan is respectively connected with a first through-flow flowmeter and a second through-flow flowmeter through a fourth through-flow pipeline and a third through-flow pipeline, the first through-flow flowmeter and the second through-flow flowmeter are respectively connected with the first through-flow pipeline and the second through-flow pipeline, and the first through-flow pipeline and the second through-flow pipeline are respectively communicated with a gun body internal full-pressure transmission pipeline and a gun body internal static pressure transmission pipeline through a ventilation air inlet at the rear end of a pulverized coal sampling gun; the front end of the pulverized coal sampling gun is provided with an airflow full-pressure acquisition hole and an airflow static pressure acquisition hole, the airflow full-pressure acquisition hole is communicated with an airflow full-pressure measuring joint arranged on the side wall of the pulverized coal sampling gun through an internal full-pressure transmission pipeline of the gun body, the airflow static pressure acquisition hole is communicated with an airflow static pressure measuring joint arranged on the side wall of the pulverized coal sampling gun through an internal static pressure transmission pipeline of the gun body, and the airflow full-pressure measuring joint and the airflow static pressure measuring joint are both connected with a wind speed measuring instrument; the front end of the pulverized coal sampling gun is also provided with a pulverized coal sampling port, the pulverized coal sampling port is connected with a primary pulverized coal separator through an internal pipeline of the gun body and an air suction port at the rear end of the pulverized coal sampling gun, the primary pulverized coal separator, a secondary pulverized coal separator and an air exhaust flow meter are sequentially connected, and the air exhaust flow meter is connected with an air exhaust fan through a valve.
Further, the air exhaust fan is connected with a branch, and a second valve is installed on the branch.
Furthermore, the airflow full-pressure collecting hole and the airflow static-pressure collecting hole are respectively arranged on the windward side and the leeward side of the pulverized coal sampling gun, and the flow velocity of the measured medium is calculated by measuring the full pressure and the static pressure; when measuring, the air from the through-flow fan is communicated in the gun body internal full-pressure transmission pipeline and the gun body internal static pressure transmission pipeline, the air finally enters the measured medium through the airflow full-pressure acquisition hole and the airflow static pressure acquisition hole, and the airflow full-pressure acquisition hole, the airflow static pressure acquisition hole, the gun body internal full-pressure transmission pipeline and the gun body internal static pressure transmission pipeline are not blocked due to the deposition of the pulverized coal even when the airflow speed with the pulverized coal is measured due to the through-flow air.
Furthermore, according to the flow velocity measured by the wind speed measuring instrument, the air exhaust flow is controlled by adjusting a first valve at the inlet of the air exhaust fan, so that the air exhaust flowmeter reads the speed in the corresponding air exhaust pipe to be the same as the measured flow velocity of the medium to be measured, and the sampling is in a constant-speed sampling state at the moment.
Furthermore, the medium flow velocity in the pipeline to be measured can be measured independently according to other speed measuring devices, then a coal powder sampling gun is inserted for sampling, and the air extraction flow is adjusted, so that the flow velocity measured independently in advance is the same as the speed of the flowmeter reading the corresponding pipe.
Further, the structure design of the gun body internal static pressure transmission pipeline and the gun body internal full pressure transmission pipeline is similar, so that the same fluid resistance characteristics (same resistance under the same flow) are ensured, and the relationship among the measurement parameters is as follows:
λ1＝λ2
υ1＝υ2
ξ1＝ξ2
in the formula: λ is an on-way resistance coefficient of the pressure transmission pipeline, ζ is a local resistance coefficient of the pressure transmission pipeline, l is a pipe length of the pressure transmission pipeline, d is a pipe hydraulic diameter of the pressure transmission pipeline, v is an in-pipe flow velocity of the pressure transmission pipeline, and P'4Is a full pressure measurement, P 'with throughflow'5As a measure of static pressure in the case of throughflow, P4For full-pressure measurement without flow, P5Is a static pressure measurement without flow.
During measurement, the static pressure transmission pipeline inside the gun body and the full pressure transmission pipeline inside the gun body are enabled to flow through and the flow rate of the through medium is kept to be smaller, and the flow rates of the static pressure transmission pipeline and the full pressure transmission pipeline inside the gun body are ensured to be equal (Q)1＝Q2) In this case, the throughflow medium generates the same line resistance on both sides, and under these conditions, the above formula yields P4-P5＝P’4-P’5Thus, the dynamic pressure Δ P ═ P characterizing the flow rate of the medium to be measured4-P5Can be through P'4And P'5Is determined.
The working method of the extraction flow readable anti-blocking coal powder constant-speed sampling system is characterized by comprising the following steps: starting a through flow fan, adjusting a first through flow flowmeter and a second through flow flowmeter to enable flow speed of through flow media in the gun body internal full-pressure transmission pipeline and the gun body internal static pressure transmission pipeline to be equal and keep small flow, and connecting an airflow full-pressure measuring joint with a pressure gauge to measure full pressure P'4Measuring static pressure P 'by connecting a pressure gauge to a static airflow pressure measuring tap'5(ii) a Full pressure value P measured by full pressure measuring joint of airflow under condition of no through flow4Static pressure value P measured by static airflow pressure measuring joint under condition of no through flow5Because of the control of the throughflow, the dynamic pressure Δ P ═ P characterizing the flow velocity of the medium to be measured4-P5＝P’4-P’5Further calculating the flow velocity of the measured medium by a relational formula of dynamic pressure and flow velocity; meanwhile, the pulverized coal sampling port is opposite to the incoming flow, and the total pressure and the static pressure are measured by the wind speed measuring instrument to visually display the in-pipe flow velocity of the measured medium; and regulating the first valve and the second valve according to the flow rate, and controlling the flow of the air exhaust flowmeter to ensure that the air exhaust speed of the corresponding sampling pipe displayed by the air exhaust flowmeter is equal to the air speed measured by the air speed measuring instrument, so that the constant-speed sampling state is achieved.
Compared with the prior art, the utility model, have following advantage and effect: a small amount of air flow is introduced into the system and sprayed into a measured medium, so that the blockage of the piezometer tube can be effectively prevented, and the normal speed measurement is ensured; the structure design of the gun body internal static pressure transmission pipeline and the gun body internal full pressure transmission pipeline is similar, the same fluid resistance characteristics (same resistance under the same flow) are ensured, and during measurement, the through flow and the through flow medium flow in the gun body internal static pressure transmission pipeline and the gun body internal full pressure transmission pipeline are kept to be smaller, and the flow of the two pipelines is ensured to be equal (Q)1＝Q2) The dynamic pressure delta P ═ P characterizing the flow rate of the medium to be measured4-P5＝P’4-P’5The accuracy of speed measurement data is ensured; the flow velocity in the medium pipe to be measured can be read, and whether the pressure measuring pipe is blocked can be judged; the flow of the air exhaust is displayed, and the sampler can be judgedWhether the working state is normal or not. Through the above way, the problems that the pressure measuring hole of the existing sampling device is easy to block and the sampling state is not easy to control are solved.
Drawings
Fig. 1 is a schematic diagram of the overall structure of the system according to the embodiment of the present invention.
Fig. 2 is a schematic cross-sectional view B-B of fig. 1.
Fig. 3 is a partial view taken from a in fig. 1.
In the figure: the device comprises an airflow total pressure acquisition hole 1, an airflow static pressure acquisition hole 2, a coal powder sampling gun 3, an airflow total pressure measurement joint 4, an airflow static pressure measurement joint 5, a wind speed measurement instrument 6, a primary coal powder separator 7, a secondary coal powder separator 8, an air extraction flowmeter 9, a first valve 10, a second valve 11, an air extraction fan 12, a first through flow meter 13, a first through flow pipeline 14, a second through flow meter 15, a gun body internal static pressure conduction pipeline 16, a gun body internal total pressure conduction pipeline 17, a through flow fan 18, a second through flow pipeline 19, a third through flow pipeline 20, a fourth through flow pipeline 21 and a coal powder sampling port 22.
Detailed Description
The present invention will be described in further detail by way of examples with reference to the accompanying drawings, which are illustrative of the present invention and are not intended to limit the present invention.
Referring to fig. 1 to 3, an extraction flow readable anti-clogging coal powder constant-speed sampling system comprises a coal powder sampling gun 3, a wind speed measuring instrument 6, a primary coal powder separator 7, a secondary coal powder separator 8, an extraction flow meter 9, a first valve 10, an extraction fan 12, a first through flow meter 13, a first through flow pipeline 14, a fourth through flow pipeline 21, a second through flow meter 15, a second through flow pipeline 19, a third through flow pipeline 20 and a through flow fan 18; the through-flow fan 18 is respectively connected with a first through-flow flowmeter 13 and a second through-flow flowmeter 15 through a fourth through-flow pipeline 21 and a third through-flow pipeline 20, the first through-flow flowmeter 13 and the second through-flow flowmeter 15 are respectively connected with a first through-flow pipeline 14 and a second through-flow pipeline 19, and the first through-flow pipeline 14 and the second through-flow pipeline 19 are respectively communicated with a gun body internal full-pressure transmission pipeline 17 and a gun body internal static-pressure transmission pipeline 16 through a circulating air inlet at the rear end of the pulverized coal sampling gun 3; the front end of the pulverized coal sampling gun 3 is provided with an airflow full-pressure acquisition hole 1 and an airflow static pressure acquisition hole 2, the airflow full-pressure acquisition hole 1 is communicated with an airflow full-pressure measurement connector 4 arranged on the side wall of the pulverized coal sampling gun 3 through a gun body internal full-pressure transmission pipeline 17, the airflow static pressure acquisition hole 2 is communicated with an airflow static pressure measurement connector 5 arranged on the side wall of the pulverized coal sampling gun 3 through a gun body internal static pressure transmission pipeline 16, and the airflow full-pressure measurement connector 4 and the airflow static pressure measurement connector 5 are both connected with a wind speed measuring instrument 6; the front end of the coal powder sampling gun 3 is also provided with a coal powder sampling port 22, the coal powder sampling port 22 is connected with a first-stage coal powder separator 7 through an inner pipeline of the gun body and an air pumping port at the rear end of the coal powder sampling gun 3, the first-stage coal powder separator 7, a second-stage coal powder separator 8 and an air pumping flowmeter 9 are sequentially connected, and the air pumping flowmeter 9 is connected with an air pumping fan 12 through a first valve 10.
Specifically, the air exhaust fan 12 is connected with a branch, and a second valve 11 is installed on the branch.
Specifically, an airflow full pressure acquisition hole 1 and an airflow static pressure acquisition hole 2 are respectively arranged on the windward side and the leeward side of a pulverized coal sampling gun 3, and the flow velocity of a measured medium is calculated by measuring the full pressure and the static pressure; during measurement, air from a through-flow fan 18 is communicated in the gun body internal full-pressure transmission pipeline 17 and the gun body internal static pressure transmission pipeline 16, the air finally enters a measured medium through the airflow full-pressure acquisition hole 1 and the airflow static pressure acquisition hole 2, and the airflow full-pressure acquisition hole 1, the airflow static pressure acquisition hole 2, the gun body internal full-pressure transmission pipeline 17 and the gun body internal static pressure transmission pipeline 16 are not blocked due to deposition of coal powder even when the airflow speed with the powder is measured due to the through-flow air.
Specifically, according to the flow rate measured by the wind speed measuring instrument 6, the first valve 10 at the inlet of the air exhaust fan 12 is adjusted to control the air exhaust flow, so that the air exhaust flowmeter 9 reads that the speed in the corresponding air exhaust pipe is the same as the measured flow rate of the measured medium, and the sampling is in a constant-speed sampling state at the moment.
Specifically, the medium flow velocity in the pipeline to be measured can be measured independently according to other speed measuring devices, then the coal powder sampling gun 3 is inserted for sampling, and the air extraction flow is adjusted, so that the flow velocity measured independently in advance is the same as the speed of the flowmeter reading corresponding pipe.
The working method comprises the following steps: the through-flow fan 18 is turned on, the first through-flow meter 13 and the second through-flow meter 15 are adjusted so that the flow velocities of the through-flow media in the gun body internal total pressure transmission pipeline 17 and the gun body internal static pressure transmission pipeline 16 are equal and a small flow rate is maintained, and the pressure gauge is connected to the airflow total pressure measuring joint 4 to measure the total pressure P'4Static pressure P 'is measured by connecting a static airflow pressure measuring joint 5 with a pressure gauge'5(ii) a Full pressure value P measured by airflow full pressure measuring joint 4 under condition of no through flow4The static pressure value P is measured by the airflow static pressure measuring joint 5 under the condition of no through flow5Because of the control of the throughflow, the dynamic pressure Δ P ═ P characterizing the flow velocity of the medium to be measured4-P5＝P’4-P’5Further calculating the flow velocity of the measured medium by a relational formula of dynamic pressure and flow velocity; meanwhile, the coal powder sampling port 22 is over against the incoming flow, and the total pressure and the static pressure are measured by the wind speed measuring instrument 6, so that the flow velocity in the pipe of the measured medium is visually displayed; according to the flow rate, the first valve 10 and the second valve 11 are adjusted to control the flow of the air extraction flow meter 9, so that the displayed air extraction speed of the corresponding sampling pipe is equal to the air speed measured by the air speed measuring instrument 6, and the constant sampling state is achieved at the moment.
Those not described in detail in this specification are well within the skill of the art.
Although the present invention has been described with reference to the above embodiments, it should not be construed as being limited to the scope of the present invention, and any modifications and alterations made by those skilled in the art without departing from the spirit and scope of the present invention should fall within the scope of the present invention.
Claims (3)
1. An extraction flow readable anti-blocking coal powder constant-speed sampling system is characterized by comprising a coal powder sampling gun (3), a wind speed measuring instrument (6), a primary coal powder separator (7), a secondary coal powder separator (8), an extraction flow meter (9), a first valve (10), an extraction fan (12), a first through flow meter (13), a first through flow pipeline (14), a fourth through flow pipeline (21), a second through flow meter (15), a second through flow pipeline (19), a third through flow pipeline (20) and a through flow fan (18); the through-flow fan (18) is respectively connected with a first through-flow flowmeter (13) and a second through-flow flowmeter (15) through a fourth through-flow pipeline (21) and a third through-flow pipeline (20), the first through-flow flowmeter (13) and the second through-flow flowmeter (15) are respectively connected with a first through-flow pipeline (14) and a second through-flow pipeline (19), and the first through-flow pipeline (14) and the second through-flow pipeline (19) are respectively communicated with a gun body internal full-pressure transmission pipeline (17) and a gun body internal static pressure transmission pipeline (16) through a circulating air inlet at the rear end of the pulverized coal sampling gun (3); the front end of the pulverized coal sampling gun (3) is provided with an airflow total pressure acquisition hole (1) and an airflow static pressure acquisition hole (2), the airflow total pressure acquisition hole (1) is communicated with an airflow total pressure measurement connector (4) arranged on the side wall of the pulverized coal sampling gun (3) through a gun body internal total pressure transmission pipeline (17), the airflow static pressure acquisition hole (2) is communicated with an airflow static pressure measurement connector (5) arranged on the side wall of the pulverized coal sampling gun (3) through a gun body internal static pressure transmission pipeline (16), and the airflow total pressure measurement connector (4) and the airflow static pressure measurement connector (5) are both connected with a wind speed measuring instrument (6); the front end of buggy sampling rifle (3) still is provided with buggy sample connection (22), buggy sample connection (22) are through the extraction opening of rifle body internal pipe way and buggy sampling rifle (3) rear end one-level coal separator (7), second grade coal separator (8), bleed-off flowmeter (9) connect gradually, bleed-off flowmeter (9) connect air exhaust fan (12) through a valve (10).
2. The extraction flow readable anti-blocking coal powder constant-speed sampling system according to claim 1, wherein the extraction fan (12) is connected with a branch, and a second valve (11) is installed on the branch.
3. The extraction flow readable anti-clogging coal dust constant-speed sampling system according to claim 1, wherein the airflow full-pressure collecting hole (1) and the airflow static-pressure collecting hole (2) are respectively arranged on the windward side and the leeward side of the coal dust sampling gun (3).
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112113799A (en) * | 2020-08-28 | 2020-12-22 | 华电电力科学研究院有限公司 | Extraction flow readable anti-blocking coal powder constant-speed sampling system and working method |
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2020
- 2020-08-28 CN CN202021842759.1U patent/CN213632796U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112113799A (en) * | 2020-08-28 | 2020-12-22 | 华电电力科学研究院有限公司 | Extraction flow readable anti-blocking coal powder constant-speed sampling system and working method |
| CN112113799B (en) * | 2020-08-28 | 2025-05-06 | 华电电力科学研究院有限公司 | A readable anti-clogging coal powder isokinetic sampling system with air extraction flow and working method |
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