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WO1998054549A1 - Instrument ultrasonique de type 'midloop' - Google Patents

Instrument ultrasonique de type 'midloop' Download PDF

Info

Publication number
WO1998054549A1
WO1998054549A1 PCT/US1997/022597 US9722597W WO9854549A1 WO 1998054549 A1 WO1998054549 A1 WO 1998054549A1 US 9722597 W US9722597 W US 9722597W WO 9854549 A1 WO9854549 A1 WO 9854549A1
Authority
WO
WIPO (PCT)
Prior art keywords
pipe
plug
ultrasonic
inspection
inspection plug
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US1997/022597
Other languages
English (en)
Inventor
Donn M. Matteson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Combustion Engineering Inc
Original Assignee
Combustion Engineering Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Combustion Engineering Inc filed Critical Combustion Engineering Inc
Priority to AU58972/98A priority Critical patent/AU5897298A/en
Publication of WO1998054549A1 publication Critical patent/WO1998054549A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
    • G01F1/667—Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/002—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow wherein the flow is in an open channel
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
    • G01F1/662—Constructional details
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
    • G01F23/28—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring the variations of parameters of electromagnetic or acoustic waves applied directly to the liquid or fluent solid material
    • G01F23/296—Acoustic waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
    • G01F23/28—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring the variations of parameters of electromagnetic or acoustic waves applied directly to the liquid or fluent solid material
    • G01F23/296—Acoustic waves
    • G01F23/2962—Measuring transit time of reflected waves
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C17/00—Monitoring; Testing ; Maintaining
    • G21C17/02—Devices or arrangements for monitoring coolant or moderator
    • G21C17/035—Moderator- or coolant-level detecting devices
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

Definitions

  • the present invention relates to a system for measuring water level or flow rate, especially in the horizontal run of pipe in a process plant, particularly a nuclear power plant.
  • U.S. Patent No. 5,541 ,969 issued July 30, 1 996 for "Midloop Water Level Monitor" describes a water level monitor responsive to the water level in a nuclear reactor vessel that is fluidly connected to a steam generator in a pressurized water nuclear steam supply system (NSSS). The measurement is made at a location in the horizontal run of pipe serving as a portion of the hot leg between the reactor vessel and the steam generator. A specially adapted measurement tank is supported laterally on the horizontal pipe, and fluidly connected thereto, such that the water level in a chamber of the tank is hydraulically balanced with the water level in the pipe. An array of heated junction thermocouples in the chamber, generate a signal indicative of water level in the pipe.
  • NSS pressurized water nuclear steam supply system
  • the ability to measure this water level accurately is particularly important during maintenance outages in a NSSS.
  • water is drained from the steam generators to facilitate examination of the internals, i.e., heat transfer tubes. While the steam generator does not serve its heat exchanging function during these maintenance periods, the water in the reactor vessel is cooled by another heat exchanger as the water continues to function as a coolant for the reactor core. Since the hot leg pipe lies in essentially a horizontal plane, the precise level of water in the pipe is important. If the water in the pipe is permitted to be too high, the inside of the generator, where work crews are performing examinations, could be flooded. If the water level in the hot leg pipe is permitted to be too low, this could jeopardize proper cooling of the nuclear core.
  • the hot leg has a direct fluid connection to the reactor vessel, the hot leg is in a convenient position for measuring the water level to ensure proper water level in the core. Therefore, accurate measurement of the precise water level in the hot leg pipe is of crucial importance for safety. Preferably, that the level may be measured from the NSSS control room where other safety equipment is monitored.
  • an ultrasonic level measuring system includes a transducer mounted on the bottom of the pipe, whereby acoustic pulses are launched through the pipe wall into the liquid. The pulses are reflected from the water surface and received by the transducer along with pulses reflected by the pipe wall and reverberations within the pipe wail.
  • Ultrasonic techniques used in nuclear and other process plants where internal pipe corrosion can be a problem must contend with the effect of cladding or other discontinuities in the pipe wall on the launched and reflected pulses.
  • the pipe is low alloy steel with a corrosion resistant clad material applied to the inside surface of the pipe.
  • the boundary between these two dissimilar materials increases the difficulty of using the ultrasonic instrument signal to accurately determine the water level, due to signal scatter at the boundary.
  • the method of applying the clad material to the pipe results in an irregular surface which also affects the operation of the ultrasonic equipment.
  • the objects are achieved by providing a plug of material of uniform composition from the outside surface of the pipe to the inside surface of the pipe, and transmitting the launched and reflected ultrasonic signals through this material for use in the signal processing by which the liquid property, particularly liquid level, is inferred.
  • a system configured in accordance with the present invention includes at least one inspection plug of substantially uniform material composition embedded in the pipe wall and having an inner end at the inner surface of the pipe, and extending outwardly to at least the outer surface of the pipe.
  • An ultrasonic transducer is mounted on the outer end of the inspection plug, for launching an ultrasonic beam through the plug and onto fluid in the pipe, and for detecting a reflected ultrasonic beam from the fluid in the pipe.
  • the processor means connected to the ultrasonic transducer is responsive to characteristics of the launched beam and reflective beam, for generating a signai commensurate with the fluid property, e.g., level, in the pipe.
  • the inspection plug extends outwardly through the insulation, preferably so that the outer surface of the plug is outside the insulation. This permits permanent mounting of the transducer and associated processor onto the plug, and furthermore, reduces any heat or radiation effect on the transducer processor, due to the distance thereof from the heat and fluid in the pipe.
  • the inspection plug is generally frustoconicai with the larger end of the cone defining the inner end of the plug and the smaller end of the cone defining the outer end of the plug.
  • FIG.1 is an illustrative view of the midloop water ievei monitor of the invention in operation between the reactor vessel and steam generator of a nuclear power plant;
  • FIG.2 is a cross-section view through the pipe and measurement device, which shows the configuration of the measurement system in accordance with the preferred embodiment
  • FIG.3 is a schematic of a plug array as utilized in an ultrasonic system for measuring flow rate.
  • FIG. 1 Description of the Preferred Embodiment Figure 1 is an illustrative, schematic rendition of a portion of a pressurized water NSSS, showing the water level monitoring system 10 situated on a horizontal run of pipe 1 2 fluidly connecting the nuclear reactor vessel 14 to the nuclear steam generator 1 6.
  • An electrical cable or the like 1 8 connects the monitoring system 10 to a console or other display device 20 in the control room 22 remote from the reactor and steam generator.
  • the hot water pipe 1 2 is in a substantially horizontal position at an elevation such that the upper region of the pipe 1 2 aligns with a portion of the steam generator head 26.
  • the shut-down cooling suction pipe (not shown) will form a vortex of cooling water while drawing the water from the hot leg pipe. This causes further problems during the maintenance activities.
  • FIG. 2 shows the preferred implementation of applicant's water level monitoring system 10.
  • the insulated pipe 1 2 as typically found in the nuclear plant, is shown in cross section.
  • the insulated metal pipe 30 has a main portion 32 of low alloy steel, having an outer surface 34 and an inner surface 36.
  • a corrosion resistant clad material 38 such as stainless steel, has been bonded to material 32, such that clad outer surface 40 is coextensive with inner surface 36.
  • Clad inner surface 42 defines the innermost surface of the pipe. The radial distance between the innermost surface 42 and the outermost surface 34, establishes the pipe wail thickness.
  • An arbitrary water level 44 is shown within the pipe 30.
  • An inspection plug 46 according to the invention having substantially uniform material composition, is embedded in the pipe wall.
  • the radially inner end 48 of the plug 46 is preferably contoured with the same radius of curvature as the inner surface 42.
  • the plug preferably narrows in the radially outward direction, to a plug outer surface 50 which is at, or radially beyond, the outer surface 34.
  • both the inner surface 48 and the outer surface 50 of the plug 46 are machined to a smoother finish than present in the inner and outer surfaces 42,34.
  • a variety of plug shapes can be utilized including cylindrical, it is preferred that the plug 46 be generally frustoconicai.
  • the plug In the preferred embodiment wherein the plug is permanently bonded to the pipe and exposed to a corrosive fluid within the pipe, the plug should be of a corrosion-resistant material such as stainless steel or Inconnel. Inconnel is particularly desirable because it can easily be welded to, and has a similar thermal expansion coefficient as, the low alloy steel.
  • an ultrasonic transducer 52 is mounted in any well known manner. This mounting can be facilitated and performance enhanced if the outer surface 50 of the plug 46, is machined at least in one region 51 thereof, to be flat and normal to a pipe radius for receiving and achieving an intimate bond with a flat lower surface 53 on transducer 52.
  • various electronics and processing components indicated at 58, are connected to the transducer 52.
  • the transducer 52 and electronics 58 can be sealed within a housing 59, which in turn can also provide radiation shielding.
  • the preferred shape of the plug 46 reduces the potential for the plug to be forced out of the pipe due to the high pressure loadings during plant operation. Because the outer surface 50 of the plug protrudes well beyond the outside diameter of the pipe holes or other mounting recesses for the transducer and/or housing do not reduce the thickness of the plug available for resisting stresses imposed on the pipe during plant operation.
  • the plug 46 could be installed in the pipe during pipe fabrication.
  • a substantially cylindrical through bore is drilled through the pipe having a diameter larger than that of the inner, wide end 48 of the plug.
  • the plug 46 is positioned in the bore, and a welding tool is inserted into the space between the bore wall and the plug. Weld beads are deposited progressively radially outward, until the plug is fully welded into place.
  • the pipe 30 is surrounded by insulating material 60. In this situation, it is desirable that the plug 46 extend outwardly through the insulation, with the outer surface 50 of the plug protruding several or more inches from the insulation, as shown in Figure 2.
  • Ultrasonic instruments are adversely affected by high temperature. With the plug according to the invention extending through the insulation, the transducer and associated electronics are located in an area that is close to normal ambient temperature during normal plant operation. Ultrasonic instruments are also sensitive to radiation. Because, for regulatory purposes, it is desirable that the instrumentation remain permanently installed on the pipe, the feature of the invention whereby the plug extends outwardly beyond the pipe installation, has the beneficial advantage in that the components which are sensitive to temperature and radiation, are located at a distance which isolates them from these detrimental factors. Moreover, space can be provided for radiation shielding as desired or necessary for long-term operation of the instrument.
  • the invention can also be utilized in a related end-use where ultrasonic techniques are utilized for measuring flow rate through a pipe having dissimilar materials.
  • the physical configuration would be substantially the same as shown in Figure 3.
  • four transducers 10a-d and associated plugs are located at four instrument locations.
  • the details of the signal processing differ from that associated with water level measurement, primarily in that the effects of turbulence during flow in a filled pipe are sensed ultrasonically.
  • one of the instruments 10a in a flow-rate measuring system 100 which is in use during plant operation, can easily be dedicated for level measurement purposes 200 during outages, by simply switching to a different mode of operation.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Acoustics & Sound (AREA)
  • Thermal Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Monitoring And Testing Of Nuclear Reactors (AREA)

Abstract

L'invention porte sur un système (10) d'instrument ultrasonique permettant de mesurer le niveau de fluide dans le parcours horizontal d'un tuyau. Ce système comprend un parcours horizontal de tuyau (12) dont les surfaces interne (42) et externe (36) forment une épaisseur de paroi, le tuyau étant constitué d'un premier matériau (32) qui est plaqué à l'intérieur avec un second matériau (38); un bouchon de contrôle (46) fabriqué dans un matériau de composition pratiquement uniforme encastré dans la paroi du tuyau, ce bouchon comportant une extrémité interne (48) au niveau de la surface interne du tuyau et s'étendant vers l'extérieur vers la surface externe du tuyau; un transducteur ultrasonique (52) monté sur l'extrémité externe (50) du bouchon de contrôle et permettant d'envoyer un faisceau ultrasonique (54) dans le bouchon et dans le fluide circulant dans le tuyau, et de détecter un faisceau ultrasonique réfléchi (56) dans ledit fluide; et un processeur (58), connecté au transducteur ultrasonique et sensible aux caractéristiques du faisceau envoyé et du faisceau réfléchi, générant un signal (18) correspondant au niveau (44) de fluide dans le tuyau.
PCT/US1997/022597 1997-05-29 1997-12-11 Instrument ultrasonique de type 'midloop' Ceased WO1998054549A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU58972/98A AU5897298A (en) 1997-05-29 1997-12-11 Midloop ultrasonic instrument

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US86464497A 1997-05-29 1997-05-29
US08/864,644 1997-05-29

Publications (1)

Publication Number Publication Date
WO1998054549A1 true WO1998054549A1 (fr) 1998-12-03

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PCT/US1997/022597 Ceased WO1998054549A1 (fr) 1997-05-29 1997-12-11 Instrument ultrasonique de type 'midloop'

Country Status (2)

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AU (1) AU5897298A (fr)
WO (1) WO1998054549A1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999054886A1 (fr) * 1998-04-17 1999-10-28 Abb Combustion Engineering Nuclear Power, Inc. Systeme d'alimentation de securite pour systeme de refroidissement a l'arret
US6741587B2 (en) 2002-04-02 2004-05-25 Nokia Corporation Inter-frequency measurements with MIMO terminals
DE102005018824B3 (de) * 2005-04-22 2006-10-19 Robert Seuffer Gmbh & Co. Kg Vorrichtung zur Füllstandsmessung in einem Flüssigkeitsbehälter
EP1968074A4 (fr) * 2005-12-27 2011-03-23 Tokyo Electric Power Co Structure de conduite d'alimentation en eau de réacteur atomique et système de débitmètre à ultrasons
CN102680055A (zh) * 2012-05-18 2012-09-19 河北省电力研究院 一种防水锤的超声波水位检测方法
JP2016001136A (ja) * 2014-06-12 2016-01-07 日立Ｇｅニュークリア・エナジー株式会社 原子力プラントの検査装置取付け方法及び検査装置取付け構造
CN109166330A (zh) * 2018-09-13 2019-01-08 沧州职业技术学院 一种城市低洼易内涝路段车辆防溺水预警系统
CN113639828A (zh) * 2020-04-24 2021-11-12 西安定华电子股份有限公司 工业参数测量系统

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4505160A (en) * 1983-02-07 1985-03-19 Nusonics, Inc. High-temperature transducer
US5295120A (en) * 1990-12-26 1994-03-15 Westinghouse Electric Corp. Hermetically sealed ultrasonic transducer system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4505160A (en) * 1983-02-07 1985-03-19 Nusonics, Inc. High-temperature transducer
US5295120A (en) * 1990-12-26 1994-03-15 Westinghouse Electric Corp. Hermetically sealed ultrasonic transducer system

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999054886A1 (fr) * 1998-04-17 1999-10-28 Abb Combustion Engineering Nuclear Power, Inc. Systeme d'alimentation de securite pour systeme de refroidissement a l'arret
US6741587B2 (en) 2002-04-02 2004-05-25 Nokia Corporation Inter-frequency measurements with MIMO terminals
DE102005018824B3 (de) * 2005-04-22 2006-10-19 Robert Seuffer Gmbh & Co. Kg Vorrichtung zur Füllstandsmessung in einem Flüssigkeitsbehälter
EP1968074A4 (fr) * 2005-12-27 2011-03-23 Tokyo Electric Power Co Structure de conduite d'alimentation en eau de réacteur atomique et système de débitmètre à ultrasons
CN102680055A (zh) * 2012-05-18 2012-09-19 河北省电力研究院 一种防水锤的超声波水位检测方法
JP2016001136A (ja) * 2014-06-12 2016-01-07 日立Ｇｅニュークリア・エナジー株式会社 原子力プラントの検査装置取付け方法及び検査装置取付け構造
CN109166330A (zh) * 2018-09-13 2019-01-08 沧州职业技术学院 一种城市低洼易内涝路段车辆防溺水预警系统
CN113639828A (zh) * 2020-04-24 2021-11-12 西安定华电子股份有限公司 工业参数测量系统

Also Published As

Publication number Publication date
AU5897298A (en) 1998-12-30

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