A method of forming a seal ring includes heating an extruded rod to a temperature above a glass transition temperature. The extruded rod has first and second ends. The method further includes bending the extruded rod into a circular structure while the temperature is above the glass transition temperature, joining the first and second ends of the extruded rod to form a semi-finished ring, and annealing the semi-finished ring.

Method of forming large diameter thermoplastic seal

A seal ring includes a weld and a thermoplastic material. The thermoplastic material has a weld elongation-at-break of at least 3%. The thermoplastic material can have a glass transition temperature of at least 100oC. The thermoplastic material with the weld can have a weld elongation-at-break of at least 3%. The seal ring can have a circumference of at least 0.62 meters. The seal ring can have a coefficient of friction of not greater than 0.45.

Large diameter thermoplastic seal

A multi-vane centrifugal fan has a fan housing and an impeller. The impeller includes a plurality of vanes arranged with a prescribed spacing in the circumferential direction and fixed to a hub rotatably driven around a shaft core. The impeller further includes an annular member for reinforcement that is provided on a side of the vanes opposite the hub. The fan housing has a bell mouth with a recessed part that is provided around a circumference of an air suction port of the fan housing. The recessed part has air suction port side end parts positioned on the side of the vanes opposite the hub and rotatably inserted in the recessed part without having a shroud.

Multi-vane centrifugal fan

PURPOSE: To prevent the conducting current of the switch element from exceeding the limit value of the conducting current which is decided by the smaller one of the excitation property of the transformer and the interrupting property of the switch element, by giving the control to the conducting period of the switch element. CONSTITUTION: The switch element 4 is turned on by the ion signal produced by the oscillator 11, and at the same time the element current, i.e. the exciting current of the transformer 3 is observed by the element current detector 7. This measured value is then compared through the comparator 9 with the value 8 set at the limit value of the conducting current which is decided by the smaller one of the excitation property of the transformer 3 and the off property of the element 4. And when the measured value reaches the set value 8, the off signal is generated by the off signal generator 10 to turn off the element 4. Thus the conducting period is of the element 4 is controlled to secure the protection against the faulty working of the circuit such as the breakdown of the element 4 and the saturation of the transformer 3. As a result, a compact and light-weight switching power source, which is suited for the power source of the electronic range or the like, can be obtained. COPYRIGHT: (C)1981,JPO&Japio

Switching power source

Arrester device for aerial transmission line

PURPOSE:To make it possible to easily perform the discrimination of inner and outer positions of flaws in a pipe material, by providing X.Y/X or X.Y/Y operators with respect to the X- and Y-components of the signal from an XY display type eddy current flaw detector. CONSTITUTION:A pipe 3 to be subjected to flaw detection having an outer surface flaw 1 and an inner surface flaw 2 receives flaw detection by the scanning of the probe 5 connected to an eddy current flaw detector 4 and both flaws are displayed on a cathode ray tube 6. An inner and outer flaw display apparatus 9 is connected to the output terminal 7 of the flaw detector 4 to allow said flaw detector 4 to perform the operation of X.Y/X and Y.X/X with respect to both X- and Y-components of a signal and output Y.X/X is inputted to the input terminal 10 of a pen recorder 8. By this method, the value of Y.X/X to the signal 1A of the outer surface flaw 1 comes to a (-) signal in second and fourth quadrants and, therefore, pen-writing recording is rocked to a lower side as shown by a mark 1B. The signal 2A of the inner surface flaw 2 is present in the first and third quadrants on the cathode ray tube 6 and, therefore, the value of Y.X/X is (+) and shaken to an upper side as shown by a mark 2B.

Apparatus for displaying inner and outer flaw

Automatic ray source return apparatus for gamma rays irradiation equipment

PURPOSE:To measure only the thickness of materials by using the first echo, which is reflected from the rear face or materials through a coated film surface, as a start signal of the time base and measuring the second echo and obtaining its time difference CONSTITUTION:A vertical probe 1 is arraned on a coated film 2 on an object 4 to be measured through a contact catalyst 3 An echo B1 of an ultrasonic wave 5, which is transmitted from the probe 1 and passes the film 2 and is reflected on the rear face of the object 4 to be measured, and an echo B2 of a part of the echo B1 which is reflected on boundaries between the object 4 to be measured and the film 2 and is reflected on the rear face of the object 4 to be measured are detected by an echo peak detector 12 through an analog converter 11 and etc The time difference is detected by a read latch memory 14, and a plate thickness is calculated and is displayed on a display part 16

Device for measuring plate thickness from above coated film by ultrasonic wave

PURPOSE:To prevent exposure to gamma-rays, by unifying a housing vessel of a gamma- rays, source and an aperture in a body CONSTITUTION:A housing vessel 12 housing a gamma-rays source and an aperture 20, are unified in a body and unified body is incorporated in a irradiating cylinder 6 and then, is inserted to a steel pipe 18 This constitution indicates that the leakage of gamma-rays at feeding and housing time is prevented

Photographing apparatus of gamma-ray transmission photograph

PURPOSE:To enable the discrimination of flat defects roughly at the right angle to the bottom surface from other defects irrelevant to the thickness by providing two vibrators on the same probe so that a slant longitudinal wave and a slant hateral wave refractively enter a test piece at the same incident point. CONSTITUTION:A longitudinal wave vibrator 2 with the angle of refraction of 45 deg. and lateral wave vibrator 3 with the angle of refraction of 45 deg. are arranged in the same probe 1 so that the longitudinal ultrasonic beam 5 and the lateral ultrasonic wave 6 reflactively enter a steel material 4 at the same incident point 7. This enables the discrimination of vertical flat defects roughly at the right angle to the bottom surface of the steel material 4 from other defects irrelevant to the thickness.

Kuroda Iwao

Papers

Apparatus for displaying inner and outer flaw

Automatic ray source return apparatus for gamma rays irradiation equipment

Device for measuring plate thickness from above coated film by ultrasonic wave

Photographing apparatus of gamma-ray transmission photograph

Shape-discrimination type 2 mode angle beam probe