Abstract: A method is provided to inspect a resiliently deflectable O-ring which tends to distort under the influence of its own weight. The O-ring is placed on a transparent support member with the central axis of the O-ring in a vertical orientation. Light is directed toward the O-ring and through the support member to cause the O-ring to cast a shadow. The distance between portions of the shadow cast by diametrically spaced apart portions of the O-ring indicate diametral measurements of the O-ring. The distance between radial edge portions of the shadow cast by the O-ring indicates the thickness of the O-ring. To detect surface flaws in the O-ring, light is directed against a small area on the surface of the O-ring while it is rotated. A variation in the characteristics of the reflected light indicates the presence of a flaw in the surface of the O-ring.

Abstract: Although the method and apparatus of the present invention can be utilized to apply either a uniform or a nonuniform covering of material over many different workpieces, the apparatus (20) is advantageously utilized to apply a thermal barrier covering (64) to an airfoil (22) which is used in a turbine engine. The airfoil is held by a gripper assembly (86) while a spray gun (24) is effective to apply the covering over the airfoil. When a portion of the covering has been applied, a sensor (28) is utilized to detect the thickness of the covering. A control apparatus (32) compares the thickness of the covering of material which has been applied with the desired thickness and is subsequently effective to regulate the operation of the spray gun to adaptively apply a covering of a desired thickness with an accuracy of at least plus or minus 0.0015 of an inch (1.5 mils) despite unanticipated process variations.

Abstract: Although the method and apparatus of the present invention can be utilized to apply either a uniform or a nonuniform covering of material over many different workpieces, the apparatus (20) is advantageously utilized to apply a thermal barrier covering (64) to an airfoil (22) which is used in a turbine engine. The airfoil is held by a gripper assembly (86) while a spray gun (24) is effective to apply the covering over the airfoil. When a portion of the covering has been applied, a sensor (28) is utilized to detect the thickness of the covering. A control apparatus (32) compares the thickness of the covering of material which has been applied with the desired thickness and is subsequently effective to regulate the operation of the spray gun to adaptively apply a covering of a desired thickness with an accuracy of at least plus or minus 0.0015 inches (1.5 mils) despite unanticipated process variations.

Abstract: Although the method and apparatus of the present invention can be utilized to apply either a uniform or a nonuniform covering of material over many different workpieces, the apparatus (20) is advantageously utilized to apply a thermal barrier covering (64) to an airfoil (22) which is used in a turbine engine. The airfoil is held by a gripper assembly (86) while a spray gun (24) is effective to apply the covering over the airfoil. When a portion of the covering has been applied, a sensor (28) is utilized to detect the thickness of the covering. A control apparatus (32) compares the thickness of the covering of material which has been applied with the desired thickness and is subsequently effective to regulate the operation of the spray gun to adaptively apply a covering of a desired thickness with an accuracy of at least plus or minus 0.0015 inches (1.5 mils) despite unanticipated process variations.

Abstract: An ultrasonic inspection system including a defect gate which can be interfaced with a digital computer. A high frequency precision oscillator and two preset counters define the start and duration of a gate period or window corresponding to an inspection depth range within the test specimen. The magnitudes and locations of the two or more largest defect indications within a gate window are determined and made available to the computer for analysis and diagnosis. A rear interface gate window is provided and a determination is made as to the presence or absence within the rear interface gate window of a signal representing the rear interface of the specimen. The distance between the interrogating transducer and the test specimen front interface is also determined at each point. Means are provided for real time control of the inspection system parameters by the computer to allow adaptive control of the inspection process based on real time diagnosis of the test data.