Nondestructive Testing Patents (Class 228/104)
  • Patent number: 4712722
    Abstract: A system for concurrent, non-destructive evaluation of partially completed welds for use in conjunction with an automated welder. The system utilizes real time, automated ultrasonic inspection of a welding operation as the welds are being made by providing a transducer which follows a short distance behind the welding head. Reflected ultrasonic signals are analyzed utilizing computer based digital pattern recognition techniques to discriminate between good and flawed welds on a pass by pass basis. The system also distinguishes between types of weld flaws.
    Type: Grant
    Filed: September 4, 1985
    Date of Patent: December 15, 1987
    Assignee: EG&G, Inc.
    Inventors: Donald W. Hood, John A. Johnson, Herschel B. Smartt
  • Patent number: 4633554
    Abstract: This is a method for repairing low alloy steel steam turbine (both high pressure and low pressure sections) or generator rotors. The defective section of the original rotor is removed and a replacement end is used, with mating attachments machined on the replacement end and the original rotor. The inner portion of the weld joining the replacement end to the original rotor is provided by a narrow gap weld, either by gas metal or by submerged arc welding. The outer 1/2-2 inches of the weld is provided by gas tungsten arc welding. The mating attachment and at least the inside 1/4 inch of the weld is bored out to remove possible crack initiation sites and to provide a smooth inspectable bore. In this manner, a fast and reliable technique is provided which provides accurate alignment, fast, essentially distortion free welding, and the superior mechanical properties of gas tungsten arc welding in the outer, more highly stressed zones.
    Type: Grant
    Filed: August 8, 1985
    Date of Patent: January 6, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Robert E. Clark, Dennis R. Amos
  • Patent number: 4586642
    Abstract: Apparatus is provided for monitoring conditions of a fine wire interconnection during a bonding operation. The apparatus comprise a system which is capable of being installed on new automatic wire bonders or retrofitted into existing automatic wire bonders of the type which employ a main bonding processor for controlling the motion of the bonding tool. The semiconductor to be bonded is connected to a reference voltage and a variable frequency oscillator is magnetically or a.c. coupled to the fine wire above the bonding tool and below the wire feed. The bonding wire incurs changes in inductive and capacitive reactance during the bonding operation which cause variations in the frequency of the oscillator. A series of frequency samples are taken and recorded during a teaching operation in which good wire bond interconnections are made.
    Type: Grant
    Filed: May 13, 1985
    Date of Patent: May 6, 1986
    Assignee: Kulicke and Soffa Industries Inc.
    Inventors: John D. Dreibelbis, I. Marvin Weilerstein
  • Patent number: 4555052
    Abstract: A method and circuits are described for sensing and detecting bond attempts and weld attempts during bonding and welding of lead wire. The method and circuitry are particularly applicable for detecting missed ball bonds and missed wedge bonds during bonding of lead wire between the die pad of a microcircuit chip and the lead frame on which the chip is mounted. A sensor (30) or sensing circuit (42) senses the different characteristic electrical condition of the lead wire (11) following a ball bond attempt and following a wedge bond attempt. A bond attempt indicator (45) indicates high resistance in the lead wire following a missed ball bond while weld attempt indicator (46) indicates low resistance in the lead wire (11) following a missed wedge bond. The lead wire (11) is isolated from uncontrolled contacts with ground potential while the lead wire is held in the bonding tool and bonding machine.
    Type: Grant
    Filed: February 28, 1983
    Date of Patent: November 26, 1985
    Assignee: Fairchild Camera & Instrument Corporation
    Inventors: John A. Kurtz, Donald E. Cousens, Mark D. Dufour
  • Patent number: 4526311
    Abstract: A method and apparatus are disclosed for carrying out repair, maintenance or testing of apparatus, components and the like in hot cells, more particularly hot cells of reprocessing plants for spent nuclear fuels. The position of damage zones is detected and ascertained with the use of coordinates. Replacement parts and tools are moved into the maintenance and work position in dependence upon the coordinate data, and the repair or maintenance work is automatically carried out under computer control, with remote operation and remote monitoring. For carrying out the work, computer-controlled handling machines and manipulators are used which are adapted to travel in controllable manner in the hot cell. The monitoring and detecting, using coordinates, of damage zones and defects may be carried out with the use of cameras and/or leak detectors.
    Type: Grant
    Filed: September 22, 1982
    Date of Patent: July 2, 1985
    Assignee: Deutsche Gesellschaft etc.
    Inventor: Gunter Schroder
  • Patent number: 4491412
    Abstract: The present method can determine the presence and amount of silvery white metallic impurities in a silvery white molten solder composition. In accordance with the method of this invention, a transparent substrate which has sequential layers of metal deposited on one of the surfaces thereof is prepared. A first layer is formed directly on the substrate of a thin film of a colored metal such as copper or gold. A second thicker layer of a silvery white metal, the presence and amount of which is desired to be evaluated in the solder composition, deposited over the first layer. In use, the substrate is placed in contact with the molten solder. The amount of time required for the second layer to dissolve into the solder bath and the exposed first colored layer to change color due to alloying with the metal of the solder, is measured. The time required for the color change to occur is correlated to the level of contamination of the silvery white metal in the solder bath.
    Type: Grant
    Filed: August 19, 1982
    Date of Patent: January 1, 1985
    Assignee: RCA Corporation
    Inventors: Shigeo Harada, Soitiro Tosima
  • Patent number: 4419562
    Abstract: Herein disclosed is a noncontact, nondestructive method for monitoring the quality of a high energy weld, e.g., laser beam weld. In accordance with the proposed method, an acoustic sensor (32) is positioned at a distance from the welding zone (34) and picks up airborne acoustic emission signals (33) associated with the laser welding process. These acoustic signals, propagating through the air space between the welding zone (34) and the sensor (32), are detected and analyzed (36,37) to determine the quality of the weld (FIG. 3).
    Type: Grant
    Filed: January 19, 1982
    Date of Patent: December 6, 1983
    Assignee: Western Electric Co., Inc.
    Inventors: Min-Chung Jon, Vito Palazzo
  • Patent number: 4416409
    Abstract: A method and apparatus of manufacturing a metal casing, particularly for accessories, such as steel casings, and preferably gate valves which can be employed in installations requiring high safety measures and testing with testing heads, the casings having large nominal widths and particularly usable in nuclear reactors and the like, comprising, permanently deforming a bloom into a tubular body having one open end and an opposite closed end, deforming at least a portion of the tubular body to form at least two diametrically opposed sides thereof which are planar on their interior and exterior surfaces, forming a port in at least one of the planar ends having a diameter less than that of the diametrically opposed sides to leave an approach area around the port and connecting a pipe connection to the port by a single welding seam which can be tested with a testing head which can approach the seam in the approach area. A casing made in accordance with the method is also disclosed.
    Type: Grant
    Filed: November 6, 1980
    Date of Patent: November 22, 1983
    Assignee: Thyssen Industrie AG
    Inventors: Erwin Muller, Bernd Kollmann, Ferdinand Sonnabend, Gert Petzolt, Josef Balz, Bernhard Walloschek, Friedrich Risse
  • Patent number: 4409333
    Abstract: A test procedure is disclosed for evaluating the solderability properties of molten solder. In the method of this invention, a testpiece is provided which has a transparent support with a film of metal such as copper deposited on one surface of the transparent support. The surface having the metal film is immersed in the molten solder and the time required for alloying to occur and be observed through the transparent support is measured to determine rate of alloying and, thereby, the solderability properties of the molten solder under evaluation.
    Type: Grant
    Filed: December 4, 1981
    Date of Patent: October 11, 1983
    Assignee: RCA Corporation
    Inventors: Soitiro Tosima, Shigeo Harada
  • Patent number: 4403410
    Abstract: A process for the manufacture of a printed circuit board is disclosed in which, during the process, conductive tracks 6 are tested for defects 8 relating to their conductivity and any detected defect 8 is repaired by securing a conductive bridge-piece 9 across the defect 8 by a reflow soldering operation. The repair is encapsulated with a protective layer 16 and the manufacturing process, which includes the further application of heat to the circuit board, is continued.
    Type: Grant
    Filed: January 14, 1981
    Date of Patent: September 13, 1983
    Assignee: International Computers Limited
    Inventor: John E. Robinson
  • Patent number: 4392044
    Abstract: A method for detecting whether dissimilar metals or alloys are being welded together is disclosed. Metals or alloys are welded together and electrical leads connected to a multi-purpose potentiometer or a voltmeter contact each metal at points heat conductively remote from the weld. The arrangement performs as a thermocouple with the weld acting as the "hot junction" and the contact points remote from the weld being at substantially ambient temperature, and acting as the "cold junction." According to the thermoelectric laws, if the metals are dissimilar, a current and EMF result provided that the hot junction and the cold junction are at different temperatures. If the metals are similar, no signal is generated. The potentiometer or the voltmeter detects whether any electrical signal is present. In the same manner, an unknown metal may be positively identified by welding it to different reference metals until no signal is generated.
    Type: Grant
    Filed: April 7, 1981
    Date of Patent: July 5, 1983
    Assignee: Amax Inc.
    Inventors: Teh P. Wang, Elmer J. Korn
  • Patent number: 4386727
    Abstract: A process is described in which a weld is produced without residual stresses; or with residual stresses reduced to a low value. Stress cycles of low value at low frequency are applied in the longitudinal direction of the weld by means of an air operated vibrator during welding. Application of stress cycles may be continued after welding, during or after reheating which may be applied to the solidified weld. Stress cycles are applied at high temperature when the weld metal is in a molten state, semi-solid state and solidified state, and thus brings about reduction in dislocation density in solidified crystals. Stress exists at each dislocation and since the dislocation density is reduced, reduction in residual stress takes place thereby eliminating the need for additional stress relieving operations. Since stress cycles are applied during welding, gases in molten metal are driven out and porosity in the solidified weld is reduced.
    Type: Grant
    Filed: May 23, 1980
    Date of Patent: June 7, 1983
    Inventor: Madhav A. Unde
  • Patent number: 4373653
    Abstract: A method and apparatus for providing high reliability ultrasonic bonds by monitoring the force required to separate the bonding tool from the wire after the bonding operation. This force which is required to break an incidental bond between the tool and the wire is related to the quality of the primary bond of the wire to a conductor terminal. The output of a transducer is proportional to the force and it may be coupled to a visual display, alarm, or computer for trend analysis.
    Type: Grant
    Filed: September 10, 1981
    Date of Patent: February 15, 1983
    Assignee: Raytheon Company
    Inventors: Thomas E. Salzer, Michael S. Masheff
  • Patent number: 4364161
    Abstract: A tank and method for fabricating the tank are disclosed wherein a longitudinally seam welded segment of a generally cylindrical steel tube is formed by hot spinning into a cylinder. The cylinder is heat treated, shot blasted, and non-destructively tested to verify that the heat treatment is uniform and proper, that the wall thickness is as desired, and that the weld region is acceptable with no critical defects created as a result of the hot spinning and heat treating. The cylinder is pressurized with air to a predetermined pressure to verify that there is no leakage from the spun closed end of the tank. Finally, the cylinder is hydrostatically tested to a predetermined pressure level with water and the cylinder weld is simultaneously examined by means of acoustic emission with the cylinder stressed in response to the internally applied hydrostatic test pressure to determine if a paste weld condition exists.
    Type: Grant
    Filed: December 29, 1980
    Date of Patent: December 21, 1982
    Assignee: The Marison Company
    Inventor: Russell C. Stading
  • Patent number: 4343424
    Abstract: A crack susceptibility test for weld metals such as the alloys of titanium, luminum and copper comprises filling a triangular pattern of grooves in a plate with weld metal wherein the groove arrangement provides the degree of restraint necessary to generate cracks in the weld metal. The grooves, which are fully contained in the plate, intersect to form a 30.degree.-60.degree.-90.degree. triangle, wherein the groove depth to plate thickness ratio is between about 0.2 and 0.8.
    Type: Grant
    Filed: May 29, 1980
    Date of Patent: August 10, 1982
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Thomas W. Montemarano, Michael E. Wells
  • Patent number: 4314131
    Abstract: This specification discloses a wire banding method and machine, which comprises a base member, a circular guideway and wire feeding and tensioning means. Wire is fed across the base and past an article to be bound and then around the guideway until the leading edge thereof strikes a stop. At this time, clamping means on a first member on the base clamps and holds the leading end of the wire. Then the feeding means is reversed to tension the wire about the article. At the end of the tensioning step a second member on the base clamps the wire and the wire is severed prior to welding, then during the welding operation means are provided to prevent the welding current from damaging the articles being banded, then after welding the ends of the wire band, the weld is tensioned to check the integrity thereof.
    Type: Grant
    Filed: November 26, 1979
    Date of Patent: February 2, 1982
    Assignee: Fryer Corporation
    Inventor: George R. Fryer
  • Patent number: 4282759
    Abstract: A method and apparatus for non-destructive testing of beam-lead integrated ircuit connections in which each of the leads from a chip beam-lead device has a pull tab made interval therewith with a weakened area and means for connecting a pull tool thereto to test the bond strength between the individual lead and the conductor to which the lead is bonded to determine if a predetermined bond exist between the lead and the conductor.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: August 11, 1981
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Jimmy D. Merrell
  • Patent number: 4213556
    Abstract: A wire bonder for making electrical connections from semiconductor chips to conductors on a lead frame includes a fault sensing system to detect a failure of the ball bond at the chip pad as well as the lead bond. Pad bond failure is detected by providing a wire feed sensor and a logic element for determining whether the wire is being fed when the bonding tip is moved from the chip to the lead. There is no wire feed if the pad bond fails. Lead bond failure is detected by clamping the wire after the lead bond is made and pulling on the wire to either break off the tail at the bond or pull the bond loose from the lead. Then the clamp is released momentarily so that if the tail has not broken free, an extra length of wire will be pulled from the tip. The extra length of wire is sensed by an electronic flame off torch monitor.
    Type: Grant
    Filed: October 2, 1978
    Date of Patent: July 22, 1980
    Assignee: General Motors Corporation
    Inventors: Frederick M. Persson, David C. Frankel
  • Patent number: 4152816
    Abstract: A method for manufacturing a turbine rotor assembly from dissimilar materials includes the step of preforming a turbine disc of powdered metal by direct hot isostatic pressing; machining the OD of the disc rim to an exact dimension; prefabricating a ring of airfoil elements having a circular rim with a machined ID therein fit to the OD of the turbine disc; sealing joint lines on side surfaces of the joined parts to create a vacuum at the interface with a high melt temperature sealant; thereafter diffusion bonding the joined and sealed parts by hot isostatically pressing them at temperatures in excess of 1500.degree. F. and under fluid pressure directly applied to the parts in excess of 1000 psi to press the ring ID into intimate contact with the OD of the disc until the dissimilar materials are diffusion bonded to form a high strength butt joint therebetween.
    Type: Grant
    Filed: June 6, 1977
    Date of Patent: May 8, 1979
    Assignee: General Motors Corporation
    Inventors: Bruce A. Ewing, Marvin Herman
  • Patent number: 4153194
    Abstract: A seal-welded pipe joint mechanically braced by a clamp for preferred use in handling toxic and radioactive materials is disclosed together with a process for joining the same. The joint comprises a pair of abutted male frustroconical skirts, each attached integrally to the pipe segments to be joined and confronting each other at opposed mating and finished surfaces which define a sunken ridge at their periphery. A uniform continuous seal weld of relatively slight penetration seals the opposed mating and finished surfaces at the ridge. The pipe joint is physically secured by a plurality of, for example, three female frustroconical segments forming a circumscribing collet which is circumferentially clamped to the skirt. When the collet is clampd over the abutted skirts with seal weld there between, the mating and finished surfaces are compressd together, relieving the seal weld of shearing and normal stresses.
    Type: Grant
    Filed: September 1, 1977
    Date of Patent: May 8, 1979
    Assignee: Bechtel International Corporation
    Inventor: Byron H. Leonard, Jr.
  • Patent number: 4144766
    Abstract: Apparatus for the on-line detection and location of weld flaws wherein the acoustic emissions from a fault are segregated from other acoustic emissions by recognizing those emissions from the weld zone falling within a predetermined band of frequencies and locating the fault by determining the time required for the recognized emissions to travel to two spaced apart predetermined points.
    Type: Grant
    Filed: May 2, 1977
    Date of Patent: March 20, 1979
    Assignee: The Babcock & Wilcox Company
    Inventor: Allen E. Wehrmeister
  • Patent number: 4144494
    Abstract: In electromagnetic testing method for tubes is disclosed, which is used during continuous production of tubing from strip being formed into a tube followed by welding the adjoining edges. A magnetic field is applied from the outside, possibly being a field accompanying the welding process, and a pickup transducer is inserted from the tube forming location to scan the interaction of the penetrating field with the tube particularly the seam and adjacent zones.
    Type: Grant
    Filed: September 12, 1977
    Date of Patent: March 13, 1979
    Assignee: Mannesmann Aktiengesellschaft
    Inventors: Reinhard Pawelletz, Heinz Schneider
  • Patent number: 4142237
    Abstract: A continuous production line is divided into a plurality of zones, with each of which there is associated a presettable counter. An anticipated length of a material, which has been calculated from information regarding the material before welding, is converted into a given number of pulse signals, which in turn are preset in the counter, with its timing being shifted a zone to zone distance. Long materials which have been sequentially joined by welding into a continuous length of material are fed into the production line, and the length of material actually fed is detected by means of a feed length gage, and an output of the gage is converted into a pulse signal. The length of the material actually fed is substracted from the anticipated length of the material, i.e., the preset count value, as the material is being fed. Thus, it is presumed that a welded joint across the length of material is present in the zone where a preset count value becomes zero as a result of the aforesaid subtraction.
    Type: Grant
    Filed: July 26, 1977
    Date of Patent: February 27, 1979
    Assignee: Sumitomo Kinzoku Kogyo Kabushiki Kaisha
    Inventor: Ikutaro Yamasaki
  • Patent number: 4130925
    Abstract: Methods of pipeline construction in arctic and subarctic regions and apparatus for carrying out those methods are disclosed. Following the disclosed methods, summer-constructed fabrication yards are established at locations along the pipeline right-of-way spaced at intervals of 100 to 150 miles. Each summer-constructed fabrication yard is regarded as being at or close to the center of its associated pipeline division, which is approximately 100 to 150 miles in length. Each fabrication yard comprises a group of summer-constructed buildings adapted for carrying out the steps in fabricating a pipe section, including quality control, X-ray, hydrostatic testing, external coating, final inspection, and river coating and weighting, along with yard facilities for moving elongated (e.g., 2500 foot) pipe sections from place to place during their fabrication, inspection, coating, etc.
    Type: Grant
    Filed: April 21, 1977
    Date of Patent: December 26, 1978
    Inventor: Murray Gibson
  • Patent number: 4095734
    Abstract: A metal wall, such as that of a vessel, is provided with cladding which is welded to the metal wall such that an elongated space is formed between the weld seams. The elongated space allows for the testing of the weld seams for leakproofness by closing off one end of the space and injecting a gaseous medium, or the like, into the space and gauging whether or not the medium exits via the weld seams. A plate made of rubber, plastic or the like may also be used in welding the cladding to the metal wall, which plate covers the unconnected ends of the two cladding parts making up the cladding layer for the metal wall.
    Type: Grant
    Filed: February 27, 1976
    Date of Patent: June 20, 1978
    Assignee: Nitro Nobel AB
    Inventor: Per Ingemar Persson
  • Patent number: 4065846
    Abstract: A seal-welded pipe joint mechanically braced by a clamp for preferred use in handling toxic and radioactive materials is disclosed together with a process for joining the same. The joint comprises a pair of abutted male frustroconical skirts, each attached integrally to the pipe segments to be joined and confronting each other at opposed mating and finished surfaces which define a sunken ridge at their periphery. A uniform continuous seal weld of relatively slight penetration seals the opposed mating and finished surfaces at the ridge. The pipe joint is physically secured by a plurality of, for example, three female frustroconical segments forming a circumscribing collet which is circumferentially clamped to the skirt by a plurality of, for example, three tangentially disposed bolts. The abutted frustroconical skirts taper from a broad cross section adjacent the pipe wall radially outwardly to a narrower cross section.
    Type: Grant
    Filed: June 14, 1976
    Date of Patent: January 3, 1978
    Assignee: Bechtel International Corporation
    Inventor: Byron Herbert Leonard, Jr.
  • Patent number: 3975810
    Abstract: A valve housing is composed of a pair of shell sections each of which has an open side surrounded by an edge face, and a semi-circular rib located within the open side and having a face slightly downwardly recessed from the associated edge face. The shell sections are placed together so that their edge faces abut, and these edge faces are welded to one another. The ribs are semi-circular in mutually opposite directions and thus form a circumferentially complete annular portion. Opposite this portion the housing is provided with an opening having a larger diameter than the portion, and after the shell sections have been welded together a material-removing tool is inserted through this opening and forms on the tubular portion a circumferentially complete annular welding face which is in part of stepped configuration.
    Type: Grant
    Filed: June 25, 1975
    Date of Patent: August 24, 1976
    Assignee: Eugen Vogt
    Inventor: Walter Siepmann