CN102435548A - Device for testing pipe resistance coefficient of water supply pipe network - Google Patents
Device for testing pipe resistance coefficient of water supply pipe network Download PDFInfo
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- CN102435548A CN102435548A CN2011102609788A CN201110260978A CN102435548A CN 102435548 A CN102435548 A CN 102435548A CN 2011102609788 A CN2011102609788 A CN 2011102609788A CN 201110260978 A CN201110260978 A CN 201110260978A CN 102435548 A CN102435548 A CN 102435548A
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Abstract
The invention relates to a device for testing a pipe resistance coefficient of a water supply pipe network. The device for testing a pipe resistance coefficient of a water supply pipe network comprises a pipe system, a pressure testing module, a flow testing module and a control system. The pipe system comprises a main pipe section, a branch pipe section, a front fire hydrant, a middle fire hydrant and a rear fire hydrant. The pressure testing module comprises pressure sensors. The pressure sensors are installed on the front fire hydrant and the middle fire hydrant. A rear control valve is arranged on the main pipe section. A front control valve is arranged on the branch pipe section. The pressure testing module is connected to the control system through an interface converter. The flow testing module comprises an ultrasonic flowmeter. The ultrasonic flowmeter is installed on the rear fire hydrant. An intelligent recording system is arranged in the control system. The device for testing a pipe resistance coefficient of a water supply pipe network is greatly developed in improvement of measurement accuracy, fast and accurate recording and high-efficiency data processing, provides a perfect method for accurate determination of a pipe resistance coefficient, and promotes the development of a pipe resistance actual measurement technology for a water supply pipe network.
Description
Technical field
The invention belongs to field of environment engineering technology, be specifically related to a kind of water supply network resistance of ducting coefficient testing device.
Background technology
Water supply network is through operation for many years, and owing to reasons such as inner-walls of duct corrosion, microbial adhesion, depositions, the flow area in the pipeline constantly reduces, and the loss of flood peak increases, and has had a strong impact on the conveyance capacity of pipeline.Therefore, comparatively the water passing capacity of crucial pipeline section in the exact grasp water supply network for setting up the water supply network realistic model, is realized safe, the rationalization operation of water supply network, all has very important significance.Yet actual water supply network is because working time is long, it is historical remote to lay, and the resistance coefficient of different pipelines differs bigger.Existing data and standard can only provide the resistance coefficient value of newly-built pipeline, can not accurately reflect the practical operation situation of pipeline.At present, domestic scholars is more to the theoretical research of resistance of ducting coefficient determination, as: " two-point method ", " three point method " or the like.But, less for the research of water supply network resistance coefficient determinator, the resistance of ducting factor detection device that Shang Weiyou is comparatively ripe.
For confirming of domestic resistance of ducting coefficient, the tube wall section that domestic some company and scientific research institution's utilization once obtain is obtained the absolute coefficient of roughness of tube wall with measuring methods such as vernier calipers, obtains the pipeline resistivity of various different tubing, various years.Since the wall of tube wall coarse along its size of pipeline, shape, highly, density; And arrangement etc. is all changing; Only if obtain the tube wall section of enough pipe ranges; And for projection irregularly shaped and that arrange the measurement or the later stage conversion method of its correct science are arranged, otherwise this manual measurement method is difficult to guarantee in accuracy.
The on-the-spot test of pipe friction has four kinds of diverse ways at present, is respectively: two-point method, three point method, four-point method, five-spot.In actual engineering, we can be according to the place of test site and the concrete condition of conduit fittings, selector be fated ground actual conditions method of testing carry out on-the-spot test.Wherein two-point method is basic skills of utilizing the survey resistance of ducting of hydraulic pipeline resistivity formulae design, also is method the most commonly used.
(1) two-point method
In actual engineering, usually " two-point method " adopted in the actual measurement of pipe friction factor.Promptly test the loss of flood peak and pipeline flow on the segment pipe, ask pipeline resistivity K value through formula 3-2.Its synoptic diagram See Figure:
In the formula: H
1, H
2---the hydraulic pressure (m) of test point;
L---H
1, H
2Between distance (m);
z
1, z
2---the ground elevation (m) of pressure tap;
Q---flow (m in the pipeline
3/ s);
" two-point method " clear principle, the field data that needs is few, and under the situation of conditions permit, using this method is most convenient measurement method efficiently in all methods.
(2) three point method
At same caliber, same tubing under the prerequisite of the same pipeline section that lays the age, has proposed the field measurement method of " three point method ", and principle is following:
Computing formula is after the factor of consideration ground elevation:
H in the formula
1, H
2, H
3---be the hydraulic pressure (m) of test point;
l
1, l
2---be H
1, H
2And H
2, H
3Between distance (m)
z
1, z
2, z
3---be the ground elevation (m) of three pressure taps;
This method has overcome the shortcoming that needs to measure the main flow, but in practical application owing to exist simultaneously in the 2nd pressure measurement and flow measurement, make this pressure release serious, the pressure tap measurement data is produced interference.
(3) four-point method
" four-point method " is on same straight pipeline, to get 4 points, and wherein 3 points use as pressure measurement, and 1 as flow measurement use, its synoptic diagram See Figure.Utilize this method can effectively avoid making this place's pressure survey produce unusual phenomenon in middle not only flow measurement but also pressure measurement.
Formula is deformed into after the factor of consideration ground elevation:
In the formula:
H
1, H
2, H
3---be the hydraulic pressure (m) of test point;
l
1, l
2, l
3---be H
1, H
2And H
2And the distance (m) between flow measurement point, flow measurement point and the H3
z
1, z
2, z
3---be the ground elevation (m) of three pressure taps;
In sum; " two-point method " test philosophy is comparatively simple, and " three point method ", " four-point method " are though be on the basis of " two-point method ", to improve, and test process is comparatively complicated; The test site condition often is difficult to realize; Because the complicacy of test process usually can cause more test error, therefore seldom adopt.
Summary of the invention
The present invention has overcome the deficiency of prior art; A kind of water supply network resistance of ducting coefficient testing device has been proposed; Said device is a purpose with the conveyance capacity that improves resistance of ducting coefficient measuring accuracy, accurate convenient grasp water supply line; Adopt " two point method ", researched and developed water supply network resistance of ducting coefficient testing device.This device is a core with the absolute pressure of two adjacent hydrants on institute's mensuration pipeline; Measure the loss of flood peak of straight length between two adjacent hydrants; And the mode that adopts hydrant to release; Measure this pipeline flow with the high-precision ultrasonic flowmeter, and then, obtain the resistance coefficient of the pipeline section of surveying through analytical calculation.This device is in the process of measuring resistance of ducting coefficient; Effectively avoided adopting differential manometer to measure the error that is caused, improved measuring accuracy greatly, operation is comparatively simple, convenient; Need not institute's mensuration pipeline is carried out digging measure, also need not to cause large tracts of land to cut off the water for a long time.Adopt this device that water supply network resistance of ducting coefficient is tested, be not merely the water supply network simulation modeling data basis is provided, also grasp the conveyance capacity of crucial water supply pipeline section, thereby the scientific management that carries out water supply network provides technical support for Running-water Company.
Technical scheme of the present invention is: water supply network resistance of ducting coefficient testing device; Comprise piping system, pressure test module, flow rate test module and control system; Said piping system comprises that main leg, a pipeline section, preceding hydrant, middle hydrant, back hydrant, said pressure test module comprise pressure transducer; On hydrant and the middle hydrant, on said main leg, be provided with the back by-pass valve control before said pressure transducer is installed in, on said pipeline section, be provided with preceding by-pass valve control; Said pressure test module is connected with control system through an interface convertor; Said flow rate test module comprises ultrasonic flow meter, and said ultrasonic flow meter is installed on the hydrant of back, is provided with the intelligent register system of a cover in said control system inside.
Said pipeline section is connected with the main leg through pipe fitting.
Hydrant is connected with the main leg through pipe fitting before said.
Hydrant is connected with the main leg through pipe fitting in said.
Said back hydrant is connected with the main leg through pipe fitting.
Said interface convertor is the RS485 converter.
The present invention has following beneficial effect:
1, adopts high-precision pressure transducer that the hydrant absolute pressure of institute's survey pipeline is measured, effectively reduced the systematic error that is caused when in the past adopting U type differential manometer measuring channel resistance coefficient.
2, in the measuring process, adopt the automatic production record of being researched and developed that mensuration force value is carried out automatic record, effectively avoided the error that manual record caused; But and the real-time rendering pressure history, the pressure Changing Pattern in the observation test process, data-handling efficiency is high, can in time adjust when pinpointing the problems.
3, adopt the independent hydrant in pressure measurement hydrant downstream on institute's survey pipeline to carry out flow rate test, the interference of effectively having avoided hydrant to release and pressure survey is caused in the process.
4, adopt high-precision pressure sensor that pipeline flow is carried out non-contact mode measuring, avoided pipe excavation, measuring accuracy is high.
5, need not the depth of burying of accurate measuring channel, only need to measure pressure measurement hydrant place ground elevation and bolt open height, can obtain measuring comparatively accurately the loss of flood peak of pipeline section, and then try to achieve resistance of ducting coefficient.
6, reducing staff; Shorten and install and debug time, improve measuring accuracy, quick and precisely there has been very much progress aspect such as record and efficient deal with data; For the accurate mensuration of resistance of ducting coefficient provides more perfect method, promoted the development of water supply network resistance of ducting measurement technology.
Description of drawings
Further specify the present invention below in conjunction with accompanying drawing and embodiment.
Accompanying drawing is a principle schematic of the present invention.
Among the figure, 1, preceding hydrant; 2, pressure transducer; 3, shielded signal wire; 4, interface convertor; 5, control system; 6, middle hydrant; 7, back hydrant; 8, ultrasonic flow meter; 9, back by-pass valve control; 10, main leg; 11, preceding by-pass valve control; 12, prop up pipeline section.
Embodiment
Further specify below in conjunction with accompanying drawing, and unrestricted scope involved in the present invention.
Shown in accompanying drawing; The present invention includes piping system, pressure test module, main leg 10, flow rate test module and control system 5, on main leg 10, be provided with a pipeline section 12, by-pass valve control 11 before on said pipeline section 12, being provided with; After system's Installation and Debugging are good; The present invention can carry out resistance coefficient test, pressure test and flow rate test, and pressure test and flow rate test need to measure simultaneously, and method of testing is:
(1) pressure test
Pressure test module adopts pressure sensor 2 carries out the absolute pressure test; The signal of exportable 4-20mA or 0-10V; The analog quantity of the numerical value of surveying is transferred to control system 5 through the shielded signal wire 3 of 4 cores with interface convertor; Interface convertor 4 is generally the RS485 converter, is provided with the intelligent register system of a cover in said control system 5 inside.The intelligence register system has comprised READ30 software, and this software can be stored into signal and figure on the control system 5, can measure 128 pressure transducers 2 at most, utilizes mode bus to communicate simultaneously.During measurement, the water delivering orifice place of hydrant 1 and back hydrant 7 before respectively two pressure transducers 2 being installed on, and preceding hydrant 1 should all be opened with the valve of back hydrant 7; In the test process; Through the intelligent register system of independent development, control system 5 can be carried out record simultaneously to two groups of pressure testing data, and the user can be according to self-demand; Setting data recording frequency, and real-time rendering pressure history.This system helps finding the execute-in-place problem, and corrigendum at any time, has improved the precision of test.
(2) flow rate test
The flow rate test module adopts the ultrasonic flow meter 8 of high-accuracy portable to carry out the pipeline flow test.During test, the back by-pass valve control 9 and the preceding by-pass valve control 11 of test pipeline section downstream end are closed.Can carry out flow rate test at middle hydrant 6 or preceding hydrant 1 place, be chosen in hydrant 7 places, back in this recommendation and carry out flow rate test, can avoid the disturbance of current centering hydrant 6 places pressure test, and fluidised form be comparatively stable, to reduce the system testing error.In the test process, open the valve of back hydrant 7 gradually, reach 100% until aperture, treat system stability after, write down under the different valve opening operating modes water flow and before the absolute pressure at hydrant 1, middle hydrant 6 places.This device adopts the noncontact mode to measure when carrying out flow rate test, and the pressure loss is little, and is simple in structure, and detecting device is installed in the pipeline outside, does not need excavation, does not destroy pipeline, and measuring accuracy is high.Need possess following condition simultaneously during the on-the-spot installation testing of the portable ultrasonic flow meter of high precision 8:
1. ultrasonic flow meter 8 must have suitable installation site, mainly is to be convenient to operating personnel to carry out the level installation;
2. the scene needs the 220v working power;
3. on-the-spotly satisfy following requirement, 10D downstream, upper reaches 5D (D is the straight warp of pipeline) with the check point straight length that is as the criterion;
4. on-the-spot pipe material and wall thickness, inner-walls of duct have not liner and liner type;
5. two kinds of mounting meanss are selected: Z type and V-type, mainly adopt the Z type to install;
6. ultrasound wave duty: normal operating conditions is shown as R;
7. ultrasonic signal intensity: can satisfy 1.8 and belong to normal, the big more measurement stability of signal intensity is high more;
8. ultrasonic flow meter and on-the-spot flowmeter are compared, and on-the-spot flowmeter needs instantaneous delivery and integrated flow shows.
(3) resistance coefficient test
When adopting this device to carry out the test of water supply network resistance of ducting coefficient; Hydrant 1, the ground elevation at middle hydrant 6 places, hydrant bolt open height before also should carrying out; And the distance of preceding hydrant 1, middle hydrant 6 is measured; After having carried out pressure test and flow rate test, utilize test result, be easy to adopt the formula of two-point method to calculate the resistance coefficient of institute's survey pipeline.
Claims (6)
1. water supply network resistance of ducting coefficient testing device; Comprise piping system, pressure test module, flow rate test module and control system; Said piping system comprises main leg, a pipeline section, preceding hydrant, middle hydrant, back hydrant, and it is characterized in that: said pressure test module comprises pressure transducer, and said pressure transducer is installed on preceding hydrant and the middle hydrant; On said main leg, be provided with the back by-pass valve control; On said pipeline section, be provided with preceding by-pass valve control, said pressure test module is connected with control system through an interface convertor, and said flow rate test module comprises ultrasonic flow meter; Said ultrasonic flow meter is installed on the hydrant of back, is provided with the intelligent register system of a cover in said control system inside.
2. water supply network resistance of ducting coefficient testing device according to claim 1 is characterized in that: said pipeline section is connected with the main leg through pipe fitting.
3. water supply network resistance of ducting coefficient testing device according to claim 1 and 2 is characterized in that: hydrant is connected with the main leg through pipe fitting before said.
4. water supply network resistance of ducting coefficient testing device according to claim 3 is characterized in that: hydrant is connected with the main leg through pipe fitting in said.
5. water supply network resistance of ducting coefficient testing device according to claim 4 is characterized in that: said back hydrant is connected with the main leg through pipe fitting.
6. water supply network resistance of ducting coefficient testing device according to claim 4 is characterized in that: said interface convertor is the RS485 converter.
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Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103983313A (en) * | 2014-05-30 | 2014-08-13 | 重庆长厦安基建筑设计有限公司 | Method for determining resistance coefficient of pipe network and method for measuring air volume of pipe network |
CN104977037B (en) * | 2014-04-14 | 2017-10-20 | 沈阳芯源微电子设备有限公司 | A kind of pipeline consistency desired result device and its application method |
CN108392767A (en) * | 2018-05-09 | 2018-08-14 | 北京建筑材料检验研究院有限公司 | Indoor fire hydrant automatic test equipment and its test method |
CN108733097A (en) * | 2018-03-23 | 2018-11-02 | 西安航天动力试验技术研究所 | A kind of parallel connection multi coil water supply network surge pressure control method |
CN109779607A (en) * | 2018-12-29 | 2019-05-21 | 长江大学 | A kind of Frictional Drag of Casing Running coefficient based on hole diameter degree of irregularity determines method and system |
CN111043092A (en) * | 2019-11-22 | 2020-04-21 | 安徽江淮汽车集团股份有限公司 | Oil way hydraulic loss testing tool and testing method |
CN111220501A (en) * | 2019-12-04 | 2020-06-02 | 西南石油大学 | On-line evaluation method for drag reducer drag reduction effect in oil pipeline |
CN112729670A (en) * | 2020-12-24 | 2021-04-30 | 联合汽车电子有限公司 | Pneumatic tool wear early warning system and early warning method thereof |
CN112925680A (en) * | 2021-02-23 | 2021-06-08 | 重庆川仪自动化股份有限公司 | Pipe network monitoring method, system, medium and electronic terminal |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN2462377Y (en) * | 2000-11-10 | 2001-11-28 | 赵洪宾 | Pipeline resistance coefficient measurer |
CN101750470A (en) * | 2008-12-17 | 2010-06-23 | 中国石油天然气股份有限公司 | Performance testing device for gas pipeline drag reduction agent |
CN202393687U (en) * | 2011-09-05 | 2012-08-22 | 青岛理工大学 | Device for testing pipeline resistance coefficient of water supply pipe network |
-
2011
- 2011-09-05 CN CN2011102609788A patent/CN102435548A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN2462377Y (en) * | 2000-11-10 | 2001-11-28 | 赵洪宾 | Pipeline resistance coefficient measurer |
CN101750470A (en) * | 2008-12-17 | 2010-06-23 | 中国石油天然气股份有限公司 | Performance testing device for gas pipeline drag reduction agent |
CN202393687U (en) * | 2011-09-05 | 2012-08-22 | 青岛理工大学 | Device for testing pipeline resistance coefficient of water supply pipe network |
Non-Patent Citations (4)
Title |
---|
《中国优秀硕士学位论文全文数据库 工程科技II辑》 20090215 常迪 城市水***阻力元件的水力特性 , 第2期 * |
常迪: "城市水***阻力元件的水力特性", 《中国优秀硕士学位论文全文数据库 工程科技II辑》 * |
王光辉: "马鞍山市供水管网***规划模型的研究", 《中国优秀硕士学位论文全文数据库 工程科技II辑》 * |
舒诗湖等: "城市给水管网***中管道比阻测定方法的改进", 《管道技术与设备》 * |
Cited By (14)
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CN104977037B (en) * | 2014-04-14 | 2017-10-20 | 沈阳芯源微电子设备有限公司 | A kind of pipeline consistency desired result device and its application method |
CN103983313A (en) * | 2014-05-30 | 2014-08-13 | 重庆长厦安基建筑设计有限公司 | Method for determining resistance coefficient of pipe network and method for measuring air volume of pipe network |
CN108733097B (en) * | 2018-03-23 | 2021-05-11 | 西安航天动力试验技术研究所 | Water hammer pressure control method for parallel multi-discharge pipe water supply pipe network |
CN108733097A (en) * | 2018-03-23 | 2018-11-02 | 西安航天动力试验技术研究所 | A kind of parallel connection multi coil water supply network surge pressure control method |
CN108392767A (en) * | 2018-05-09 | 2018-08-14 | 北京建筑材料检验研究院有限公司 | Indoor fire hydrant automatic test equipment and its test method |
CN108392767B (en) * | 2018-05-09 | 2023-06-30 | 北京建筑材料检验研究院股份有限公司 | Comprehensive automatic test equipment and test method for indoor hydrant |
CN109779607A (en) * | 2018-12-29 | 2019-05-21 | 长江大学 | A kind of Frictional Drag of Casing Running coefficient based on hole diameter degree of irregularity determines method and system |
CN111043092A (en) * | 2019-11-22 | 2020-04-21 | 安徽江淮汽车集团股份有限公司 | Oil way hydraulic loss testing tool and testing method |
CN111043092B (en) * | 2019-11-22 | 2021-03-30 | 安徽江淮汽车集团股份有限公司 | Oil way hydraulic loss testing tool and testing method |
CN111220501A (en) * | 2019-12-04 | 2020-06-02 | 西南石油大学 | On-line evaluation method for drag reducer drag reduction effect in oil pipeline |
CN111220501B (en) * | 2019-12-04 | 2022-04-29 | 西南石油大学 | On-line evaluation method for drag reducer drag reduction effect in oil pipeline |
CN112729670A (en) * | 2020-12-24 | 2021-04-30 | 联合汽车电子有限公司 | Pneumatic tool wear early warning system and early warning method thereof |
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Application publication date: 20120502 |