Abstract: A control apparatus for a gas-turbine aeroengine having discriminator that discriminates normality of a low-pressure turbine rotational speed sensor adapted to detect the low-pressure turbine rotational speed and a high-pressure turbine rotational speed controller that establish a first value as an upper limit value of a high-pressure turbine rotational speed and controls the high-pressure turbine rotational speed based on the established upper limit value, and is configured to change the upper limit value to a second value lower than the first value when the low-pressure turbine rotational speed sensor is discriminated not to be normal, whereby engine output (thrust) determined by the low-pressure turbine rotational speed can be controlled to a desired value while restraining the high-pressure turbine rotational speed to not greater than the first value, and low-pressure turbine overspeed at the time of a mishap such as engine fan blade breakage can be reliably prevented.

Abstract: An apparatus for controlling an aeroplane gas turbine engine has various sensors and devices for operating the engine, and two control channels each calculating a command value for controlling operation of the engine based on signals outputted from the sensors. In each of the control channels, it is determined whether any of the sensors and devices is abnormal based on the signals to determine a failure level of the control channel concerned with a numerical value. The failure level is compared with that of the other control channel and based thereon, the command value calculated by the control channel of smaller failure level is sent to the devices. With this, even when both control channels are failed, the engine control can be continued with taking the failure level into account.

Abstract: A control apparatus for a gas-turbine aeroengine having discriminator that discriminates normality of a low-pressure turbine rotational speed sensor adapted to detect the low-pressure turbine rotational speed and a high-pressure turbine rotational speed controller that establish a first value as an upper limit value of a high-pressure turbine rotational speed and controls the high-pressure turbine rotational speed based on the established upper limit value, and is configured to change the upper limit value to a second value lower than the first value when the low-pressure turbine rotational speed sensor is discriminated not to be normal, whereby engine output (thrust) determined by the low-pressure turbine rotational speed can be controlled to a desired value while restraining the high-pressure turbine rotational speed to not greater than the first value, and low-pressure turbine overspeed at the time of a mishap such as engine fan blade breakage can be reliably prevented.

Abstract: In an overspeed protection apparatus for a gas turbine engine having a turbine rotated by combustion gas injected from a combustion chamber to drive a compressor, a fuel shutoff valve to shut off fuel to be supplied to the engine and a controller controlling operation of the fuel shutoff valve based on a turbine rotational speed to protect the turbine from overspeed, an outlet pressure of the compressor is detected and compared with a threshold value when a shutoff command is outputted, and the fuel shutoff valve is determined to be failed when the detected pressure is not less than the threshold value, thereby enabling to promptly detect the fuel shutoff valve failure without additional installing sensor, thereby enhancing the reliability.

Abstract: In an overspeed protection apparatus for a gas turbine engine having a turbine rotated by combustion gas injected from a combustion chamber to drive a compressor, a fuel shutoff valve to shut off fuel to be supplied to the engine and a controller controlling operation of the fuel shutoff valve based on a turbine rotational speed to protect the turbine from overspeed, an outlet pressure of the compressor is detected and compared with a threshold value when a shutoff command is outputted, and the fuel shutoff valve is determined to be failed when the detected pressure is not less than the threshold value, thereby enabling to promptly detect the fuel shutoff valve failure without additional installing sensor, thereby enhancing the reliability

Abstract: An apparatus for controlling an aeroplane gas turbine engine has various sensors and devices for operating the engine, and two control channels each calculating a command value for controlling operation of the engine based on signals outputted from the sensors. In each of the control channels, it is determined whether any of the sensors and devices is abnormal based on the signals to determine a failure level of the control channel concerned with a numerical value. The failure level is compared with that of the other control channel and based thereon, the command value calculated by the control channel of smaller failure level is sent to the devices. With this, even when both control channels are failed, the engine control can be continued with taking the failure level into account.

Abstract: In a gas turbine aeroengine control system, in Ch-A (first control channel), a first CPU monitors the operation of a second CPU and the second CPU monitors the operation of the first CPU; in Ch-B (second control channel), third and fourth CPUs similarly monitor each other, and when the operation of at least one of the first and second CPUs in Ch-A is found not to be normal, the output sent to an FCU (fuel control unit) is switched from the output of one or the other of the first and second CPUs of Ch-A to the output of one or the other of the third and fourth CPUs of Ch-B, thereby achieving improved CPU failure detection and realizing high redundancy and high reliability.

Abstract: In a gas turbine aeroengine control system, in Ch-A (first control channel), a first CPU monitors the operation of a second CPU and the second CPU monitors the operation of the first CPU; in Ch-B (second control channel), third and fourth CPUs similarly monitor each other, and when the operation of at least one of the first and second CPUs in Ch-A is found not to be normal, the output sent to an FCU (fuel control unit) is switched from the output of one or the other of the first and second CPUs of Ch-A to the output of one or the other of the third and fourth CPUs of Ch-B, thereby achieving improved CPU failure detection and realizing high redundancy and high reliability.

Abstract: This invention relates to a method for regenerating a cyclic olefin hydration catalyst, in which a solid acid catalyst is regenerated after its use in a hydration reaction of a cyclic olefin by mixing a water phase containing the solid acid catalyst and an oil phase containing the cyclic olefin and thereby effecting the reaction, which comprises separating the reaction solution into oil phase and water phase at a temperature of 40° C. or more and subsequently subjecting at least a portion of the solid acid catalyst in the separated water phase to a regeneration treatment. According to the method of this invention, a catalyst used in the hydration of a cyclic olefin can be separated and regenerated efficiently, and it is a particularly suitable catalyst regeneration method for a case in which hydration of a cyclic olefin is carried out for a prolonged period of time by repeating regeneration and use of the catalyst again and again.

Abstract: The present invention provides a method for producing .epsilon.-caprolactam, which comprises subjecting cyclohexene to a hydration reaction to obtain cyclohexanol, subjecting the cyclohexanol to a dehydrogenation reaction to obtain cyclohexanone, subjecting the cyclohexanone to an oxime-forming reaction to obtain cyclohexanone oxime, and subjecting the cyclohexanone oxime to a Beckmann rearrangement reaction to obtain .epsilon.-caprolactam, wherein methylcyclopentanones contained in the cyclohexanone subjected to the oxime-forming reaction are controlled to be not more than 400 ppm.According to the present invention, it is possible to produce .epsilon.-caprolactam having a quality not inferior to conventional quality at a low cost.

Abstract: The cold rolled steel sheet or galvanized steel sheet comprises by weight C: 0.0001 to 0.0026%, Si: not more than 1.2%, Mn: 0.03 to 3.0%, P: 0.015 to 0.15%, S: 0.0010 to 0.020%, Al: 0.005 to 0.1%, N: 0.0005 to 0.0080% and B: 0.0003 to 0.0030% with the balance consisting of Fe and unavoidable impurities. A process for producing the above steel sheet is also provided which comprises the steps of: performing hot roll finishing of a slab having the above chemical composition at the Ar.sub.3 transformation point or above; preferably, then cooling the hot rolled strip, within 1.5 sec after the completion of the hot rolling, to 750.degree. C. at a rate of not less than 50.degree. C./sec; coiling the strip in the temperature range of from room temperature to 750.degree. C.; cold rolling the coiled strip a reduction ratio of not less than 70%; subjecting the cold rolled strip to continuous annealing at 600.degree. to 900.degree. C.

Abstract: A method of the continuous casting of molten metal by continuously withdrawing a strand is disclosed. The method is characterized in that the thickness of the strand is continuously reduced at a rate of 0.5 mm/min to less than 2.5 mm/min in the region between the point of time when the center of the strand has a temperature corresponding to a solid-phase ratio being within the range of 0.1 to 0.3 and the point of time when said temperature has dropped to a level corresponding to the solid-phase ratio at the limit of fluidization, while substantially no reduction in thickness is effected in the region between the point of time when the center of the strand has a temperature corresponding to the solid-phase ratio at the limit of fluidization and the point of time when said temperature has dropped to the solidus line.