公开(公告)号：US4264041A

公开(公告)日：1981-04-28

申请号：US79775

申请日：1979-09-28

申请人： John B. Kitto, Jr. ,  Edwin Kowalski

发明人： John B. Kitto, Jr. ,  Edwin Kowalski

IPC分类号： B02C4/00 ,  B02C15/00 ,  B02C15/06

CPC分类号： B02C15/001

摘要： A new and improved design of a pulverizer air throat for low-pressure drop, reduced erosion and improved flow distribution.

摘要翻译： 一种新的改进的粉碎机空气喉设计，用于低压降，减少侵蚀和改善流量分布。

公开(公告)号：US4245618A

公开(公告)日：1981-01-20

申请号：US949729

申请日：1978-10-10

申请人： Murray Wiener

发明人： Murray Wiener

IPC分类号： F22B1/00 ,  F24S20/20 ,  F24S23/70 ,  F24J3/02

CPC分类号： F24J2/07 ,  F22B1/006 ,  F24J2/10 ,  F24J2002/1076 ,  F24J2002/261 ,  Y02E10/41

摘要： The present invention relates to a solar central receiver or steam generating and superheating unit (20) comprised of a first and a second series of circularly disposed tube panels (21) and (23), respectively. The first series (21) including steam superheating tube panels (12-12') and (14-14') and the second series including steam generating tube panels (16-16'). The steam generating tube panels (16-16') being interposed between at least some of the steam superheating panels (12-12') and (14-14') and the solar heat source.

摘要翻译： 本发明涉及一种太阳能中央接收器或蒸汽发生和过热单元（20），其分别包括第一和第二系列圆形布置的管板（21）和（23）。 第一系列（21）包括蒸汽过热管板（12-12'）和（14-14'），第二系列包括蒸汽发生管板（16-16'）。 蒸汽发生管板（16-16'）插入至少一些蒸汽过热板（12-12'）和（14-14'）和太阳能热源之间。

公开(公告)号：US4110620A

公开(公告)日：1978-08-29

申请号：US556762

申请日：1975-03-10

申请人： Robert E. Womack

发明人： Robert E. Womack

IPC分类号： G01T1/167 ,  G21C17/07 ,  G01T1/20

CPC分类号： G21C17/07

摘要： A typical embodiment of the invention detects leaking fuel rods by means of a radiation detector that measures the concentration of xenon-133 (Xe.sup.133) within each individual rod. A collimated detector that provides signals related to the energy of incident radiation is aligned with one of the ends of a fuel rod. A statistically significant sample of the gamma radiation (.gamma.-rays) that characterize Xe.sup.133 is accumulated through the detector. The data so accumulated indicates the presence of a concentration of Xe.sup.133 appropriate to a sound fuel rod, or a significantly different concentration that reflects a leaking fuel rod.BACKGROUND OF THE INVENTION1. Field of the InventionThis invention relates to inspection techniques, and more particularly, to a radiation detection method and apparatus for identifying leaking fuel rods within a nuclear reactor core, and the like.2. Summary of the Prior ArtNuclear reactors for power generation, for research and for other purposes need a "critical" concentration of fissionable material. This concentration--or reactor "core"--frequently comprises an array of long, slender, hollow metal rods, or "cladding," that each contain a respective stack of fuel pellets. The fuel pellets most commonly encountered are formed of uranium dioxide (UO.sub.2).During reactor operation, some of the fissionable uranium nuclei in these fuel pellets absorb neutrons that cause the respective uranium nuclei to split into two new nuclei, each with about half of the atomic mass of the parent uranium nucleus. These new nuclei, which are frequently radioactive, should remain within the enclosing metal rod. Escape of these radioactive materials from the fuel rod structure could lead to serious safety problems, or at least to the need to conduct a troublesome and costly radiation decontamination effort.The environmental conditions in power reactor cores tend to aggravate this situation. Thus, high temperatures, pressures and intense radiation within the core can produce an occasional fuel rod failure in the form of a tiny rupture in the cladding.In the case of a pressurized water reactor, for example, the "primary coolant," or water under pressure that removes heat from the reactor core, is monitored for radioactivity. An appreciable increase in the radioactivity of this water from some predetermined mined level is indicative of one or more "failed" fuel rods within the reactor core. This conclusion is based on the assumption that these additional radioactive contaminants probably have leaked out of a fuel rod and into the adjacent stream of flowing water.On registering an undesirably high level of radioactive contamination in the primary coolant, the reactor must be shut down and the individual fuel rods inspected to identify and replace the one or more rods that have failed. The task of inspecting these rods, especially in a power reactor, is very difficult and quite expensive. For instance, the heavy reactor pressure vessel must be opened, each of the bundles of 200 or more fuel rods that comprise the individual fuel elements from which the reactor core is assembled must be removed from the core and individually inspected for the presence of a failed fuel rod. In this respect it should be noted that commercial power reactors each may have as many as 36,000 or more fuel rods in the core.The actual inspection technique that is usually employed is known as "sipping." In this technique, the fuel element is placed in a "sipping can" and water or air is pumped through the fuel element assembly. The fluid flowing from the assembly is monitored for the presence of radiation. The observation of an inordinate amount of radiation in the effluent indicates the possibilities of either a failed fuel rod within the fuel element undergoing inspection or that the fluid is scouring from the rods radioactive contamination that adhered to the rod surfaces. In addition to this ambiguous indication, there is the further possibility that a rod which does leak under normal reactor operating conditions might not leak in the conditions that exist within the sipping can.Another technique requires the removal of an individual fuel rod from a fuel element assembly. This is, of course, a difficult and time-consuming task, especially if the fuel in question has been partially used, or "burned," and produces so high a level of radiation that fuel rod removal must be accomplished behind radiation shielding with remote control manipulators.The rod in question is sealed in a receptacle that has a chamber, or plenum, for accumulating any fission products that might leak from the rod. A radiation detector is spaced from a portion of the plenum by means of a radiation absorbing shield that has a passageway, or collimator, which aligns the radiation detector with the portion of the plenum under observation. In this way, the detector generates an electrical signal in response to any radioactive fission products that may have escaped from the fuel rod. Naturally, an abnormally high radiation level in the plenum portion is indicative of a possible rupture in the fuel rod. This particular technique also relies on the detection of fission products outside of the fuel rod cladding. Thus, if the fuel rod in question leaks during reactor operation, but does not leak in the inspection environment, a fuel rod that is in fact defective might actually remain undetected.With respect to detection of these radioactive fission products, it should be noted that a number of radioactive elements emit .gamma.-rays. In many instances, these .gamma.-rays have energies which are unique to a particular isotope of the element in question, e.g. Xe.sup.133, or the isotope of the element xenon that has an atomic mass of 133 units, emits a characteristic .gamma.-ray of 0.085 million electron volts (MeV) energy. The "half-life" of this particular isotope, moreover, is approximately 5.3 days. Thus, during a period of 5.3 days half of the Xe.sup.133 atoms present in a given quantity each will have emitted an 0.085 MeV .gamma.-ray. In view of the essentially random nature of the .gamma.-ray emissions from radioactive nuclei, in order to clearly identify the presence and concentration of a specific material, it is necessary for the detector to observe a sample for a sufficiently long period to accumulate a statistically significant number of detected .gamma.-rays of an energy that characterizes the material in question. This statistical determination depends on a number of variables--detector sensitivity, background radiation level, and the like. It is, however, a problem that nuclear instrumentation specialists have successfully treated for many years.Clearly, a radiation detector that is sensitive to the energy of the incident .gamma. radiation is needed for work of this nature. Generally, crystal scintillation detectors and semiconductor detectors provide this particular feature. More particularly, a semiconductor detector that typically comprises a "lithium drifted germanium" crystal, or cyrstal portion, responds to an incident .gamma.-ray by generating an electrical signal that is related to the energy lost by the .gamma.-ray within the crystal structure. The electrical signal generated in the foregoing manner is processed to identify those incident radiations. In this respect, a conventional electrical system that includes amplifiers and pulse height discriminator circuits isolates those signals that identify .gamma.-rays in the energy range of interest. Each of these identified signals is termed a "count" and is added to a cumulative total of these counts to provide some indication of the presence of the associated isotope and, in appropriate circumstances, a further indication of the concentration of the isotope in the sample under consideration.Thus, the prior art offered some means for detecting and identifying defective fuel rods. These prior art procedures were time-consuming, inefficient and frequently led to ambiguous or unreliable results. Consequently, there is a need for an improved technique for identifying failed fuel rods, especially within the reactor pressure vessel.SUMMARY OF THE INVENTIONThese and other problems that have characterized the prior art are, to a large extent, overcome through the practice of the invention. More particularly, a radiation energy-sensitive detector is enclosed in a shielded container, formed of iron or an equivalent material. The shield, moreover, is provided with a small collimating "tunnel" through which radiation emanating from one direction only may reach the detector. The collimator is aligned with the top of one of the fuel rods and kept in this alignment for a sufficient period of time to enable a statistically valid accumulation of counts to be registered to identify the presence of an appropriate concentration of radioactive fission products within the fuel rod cladding. If the proper concentration of fission products, or of a specific fission product, within the cladding are registered by the detector, it can be assumed that the structural integrity of the fuel rod has not been violated. Should the observed fission product inventory within the fuel rod be less than some standard that is commensurate with the use and exposure of the rod in question, it can be assumed that the rod under inspection has ruptured and has discharged some of the fission products.In accordance with the present invention, the shielded and collimated detector observes fission product concentration within the fuel rod, and thereby establishes an indication of fuel rod integrity that is independent of the ability of the rod to discharge fission products into a test environment during inspection.Further in this respect, the shielded and collimated detector can be mounted on an indexing device that selectively aligns the collimator and the detector with the ends of successive fuel rods that comprise the fuel elements in a reactor core, or in a fuel handling and storage canal. A typical indexing device is shown in F. S. Jabsen U.S. Pat. No. 3,894,327 filed on Oct. 23, 1973 and granted July 15, 1975 for "Industrial Technique", assigned to the same assignee as the instant invention. In this manner, the structural integrity of each fuel rod can be determined through direct observation without removing the individual rods from the reactor core or the fuel element array.The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawing and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.

摘要翻译： 本发明的典型实施例通过辐射检测器来检测泄漏的燃料棒，该辐射检测器测量每个单独的杆内的氙133（Xe133）的浓度。 提供与入射辐射能量相关的信号的准直检测器与燃料棒的一个端部对齐。 表征Xe133的伽马辐射（γ射线）的统计学显着样本通过检测器积累。 如此积累的数据表示存在适合于声音燃料棒的Xe133浓度，或者反映泄漏的燃料棒的浓度显着不同。

公开(公告)号：US4110157A

公开(公告)日：1978-08-29

申请号：US740637

申请日：1976-11-10

申请人： Felix S. Jabsen

发明人： Felix S. Jabsen

IPC分类号： G21C7/14 ,  G21C7/12 ,  G21C7/08

CPC分类号： G21C7/12 ,  G21Y2002/206 ,  G21Y2002/402 ,  G21Y2004/30 ,  G21Y2004/301 ,  Y02E30/39 ,  Y10T403/583 ,  Y10T403/7007

摘要： An illustrative embodiment of the invention provides a control rod system locking device adapted to engage an elongated extension shaft, releasably coupled at one end to the control rod assembly and releasably coupled at its other end to the control rod drive, to prevent rotation of the shaft about its longitudinal axis with respect to the control rod assembly.

摘要翻译： 本发明的说明性实施例提供了一种控制杆系统锁定装置，其适于接合细长的延伸轴，该细长的延伸轴在一端可释放地联接到控制杆组件并且在其另一端可释放地联接到控制杆驱动器，以防止轴的旋转 围绕其纵向轴线相对于控制杆组件。

公开(公告)号：US5274226A

公开(公告)日：1993-12-28

申请号：US977474

申请日：1992-11-17

申请人： John J. Kidwell ,  Stuart E. Reed

发明人： John J. Kidwell ,  Stuart E. Reed

IPC分类号： G01D5/353 ,  H01J5/16

CPC分类号： G01D5/35345 ,  G01D5/35374

摘要： A single optical fiber is used for measuring angular or rotational position in a rotary sensor. The optical fiber is used in connection with known analog intensity opto-electronics. The optical fiber is used in connection with a microbending device housed within the sensor. An input shaft of the sensor experiencing rotational motion causing the microbending device to subject the optical fiber to microbending. Microbending can be caused by a crankpin, pins located on the shaft within the housing, a transverse hole located through the shaft, or other loading arrangement. A micrometer lead screw can be used within the housing to convert the rotational motion into linear motion. The converted linear displacement is used to compress the optical fiber. Where the input shaft experiences many rotations or multiple turns the linear displacement can be applied to a spring element for carrying a load or force to a compression device. Microbending experienced by the optical fiber causes a change in the fiber radius of curvature. These microbending losses are then measured by the opto-electronics or photodetection arrangements.

摘要翻译： 单个光纤用于测量旋转传感器中的角度或旋转位置。 光纤与已知的模拟强度光电元件结合使用。 光纤用于与传感器内容纳的微弯曲装置相结合。 传感器的输入轴经历旋转运动，导致微弯曲装置使光纤受到微弯曲。 微弯可以由曲柄销，位于壳体内的轴上的销，穿过轴的横向孔或其他装载装置引起。 可以在外壳内使用千分尺丝杠将旋转运动转换成直线运动。 转换的线性位移用于压缩光纤。 在输入轴经受许多转动或多圈的情况下，可以将线性位移施加到弹簧元件，以将负载或力传递到压缩装置。 光纤经历的微弯导致纤维曲率半径的变化。 然后通过光电子或光电检测装置测量这些微弯损耗。

公开(公告)号：US5065472A

公开(公告)日：1991-11-19

申请号：US645220

申请日：1991-01-24

申请人： Steven P. Carpenter ,  James C. Cavinee ,  James J. Krannitz

发明人： Steven P. Carpenter ,  James C. Cavinee ,  James J. Krannitz

IPC分类号： F23J3/00 ,  F28G15/04

CPC分类号： F28G15/04

摘要： A brake assembly for impeding the longitudinal travel of a moving object. The brake asembly provides for a biasing mechanism which biases an engagement block into the line of travel of the moving object. When the moving object contacts the block, movement is impeded until the object is subjected to a force capable of deflecting the block counter to the biasing member and out of the line of travel of the object. The object can thereafter move past the said brake assembly and continuing along its line of travel. In particular, the brake assembly is used to impede the longitudinal travel of a reciprocating sootblower until the cleaning nozzles of the sootblower have had their position indexed relative to a previous cleaning cycle.

摘要翻译： 一种制动组件，用于阻止运动物体的纵向移动。 制动组件提供偏置机构，其将接合块偏置到移动物体的行进线中。 当移动物体与块接触时，运动被阻碍，直到物体受到能够偏转与偏压构件的块计数器并且偏离物体的行进线的力。 该物体此后可以移动经过所述制动组件并沿其行进线继续。 特别地，制动器组件用于阻止往复吹灰机的纵向行进，直到吹灰器的清洁喷嘴相对于先前的清洁循环已经将其位置分度。

公开(公告)号：USRE32517E

公开(公告)日：1987-10-13

申请号：US812071

申请日：1985-12-23

申请人： John E. Nelson

发明人： John E. Nelson

IPC分类号： F28G1/16

CPC分类号： F28G1/166 ,  F28G1/163

摘要： A method and apparatus for deslagging high temperature water walls of boilers while steaming, utilizing a jet of water applied in such manner as to develop sufficient mechanical energy to dislodge the slag without chilling the wall to a harmful degree.

公开(公告)号：US4177765A

公开(公告)日：1979-12-11

申请号：US933299

申请日：1978-08-14

申请人： Allen E. Wehrmeister

发明人： Allen E. Wehrmeister

IPC分类号： F22B31/00 ,  F22B35/00 ,  F22B1/02 ,  F23D19/02

CPC分类号： F22B35/00 ,  F22B31/0015

摘要： A fluidized bed boiler is equipped with a plurality of slidable sleeves circumscribing the vapor generator tubes disposed therein. By selectively extending or retracting the sleeves over the tubes, the heat transfer characteristics of the tubes exposed to the heat generated within the boiler may be altered. As a consequence, steam output quantity and quality may be easily modulated. In addition, by virtue of the design, tube cleaning may be accomplished with each adjustment pass.

摘要翻译： 流化床锅炉配备有围绕设置在其中的蒸气发生器管的多个可滑动套筒。 通过选择性地将套管延伸或缩回到管上，暴露于在锅炉内产生的热量的管的传热特性可以改变。 因此，可以容易地调节蒸汽输出量和质量。 另外，通过设计，可以通过每次调整通过完成管清洁。

公开(公告)号：US4891511A

公开(公告)日：1990-01-02

申请号：US238695

申请日：1988-08-31

申请人： Stuart E. Reed

发明人： Stuart E. Reed

IPC分类号： G01D5/353

CPC分类号： G01D5/35377 ,  G01D5/35374

摘要： A fiber optic microbend sensor with a braided arrangement of multiple optical fibers (or fibers and fillers) 16 such that the length dependent microbending losses result from the interaction of the fibers 10 themselves (or the fibers and fillers) without the need for additional external structures such as corrugated plates 12, 14. A plurality of fibers with at least one of the fibers being an optical fiber 10 are braided together into an interwoven strand 16 to produce the fiber optic microbend sensor. The spatial bend frequency of the braid 16 corresponds to the optimum microbend frequency for the fiber 10.

摘要翻译： 具有多根光纤（或纤维和填料）16的编织布置的光纤微弯传感器，使得长度相关的微弯曲损耗由纤维10自身（或纤维和填料）的相互作用产生，而不需要额外的外部结构 例如波纹板12,14。具有光纤10中的至少一个光纤的多个光纤被编织在一起成为交织链16以产生光纤微弯曲传感器。 编织物16的空间弯曲频率对应于纤维10的最佳微弯曲频率。

公开(公告)号：US3947686A

公开(公告)日：1976-03-30

申请号：US464079

申请日：1974-04-25

申请人： Adrianus A. G. Cooper ,  Phillip M. Leopold

发明人： Adrianus A. G. Cooper ,  Phillip M. Leopold

IPC分类号： A61B6/04 ,  G03B41/16

CPC分类号： A61B6/0442

摘要： A patient support of an X-ray unit fabricated from a generally radiolucent graphite fiber reinforced epoxy outer shell and an inner foam core.

摘要翻译： 由通常为射线可透过石墨纤维增强的环氧树脂外壳和内泡沫芯制成的X射线单元的患者支架。