High temperature permeameter for measuring magnetic properties

Instrument for measuring magnetic permeability of materials undergoing heat treatment as method for monitoring stress relief and tempering is described. Procedure is based on magnetic potentiometer principle with yoke compensating coils to cancel effects of reluctance of yoke and joint gaps. Instrument is heated with specimen being heat treated

Application of a flight-line disk crack detector to a small engine

A disk crack detector was developed and applied to a small military engine for use as a flight-line turbine crack monitor. The system consists of an eddy current type sensor and its cables within the engine, external connecting cables, and a remotely located electrical capacitance-conductance bridge and signal analyzer. As the turbine spins, the rotor is monitored by the sensor for radial surface cracks emanating from the interblade region of the rotor

Investigation of magnetically soft, high-temperature cobalt-iron alloy

Magnetically soft, high temperature cobalt-iron allo

In-service turbine wheel crack monitor

System can be utilized in flight or at flight line. It monitors disk rim for surface cracks emanating from blade root interface. System consists of eddy-current sensor, mounted approximately 1 1/2 mm (1/16 in) away from face of disk, and remotely located electrical capacitance-conductance bridge and signal analyzer

Precision optical angular position marker system for rotating machinery

An optical system is described which generates one or more markers of the angular shaft position of rotating machinery. The system consists of a light source, an optical cable, a machinery mounted lens assembly, a light detector, and a signal conditioner. Light reflected by targets on the rotor is converted to a digital output signal. The system is highly immune to extreme environments of vibration and temperature and achieved a 0.002 percent precision under operational test conditions

In-place recalibration technique applied to a capacitance-type system for measuring rotor blade tip clearance

The rotor blade tip clearance measurement system consists of a capacitance sensing probe with self contained tuning elements, a connecting coaxial cable, and remotely located electronics. Tests show that the accuracy of the system suffers from a strong dependence on probe tip temperature and humidity. A novel inplace recalibration technique was presented which partly overcomes this problem through a simple modification of the electronics that permits a scale factor correction. This technique, when applied to a commercial system significantly reduced errors under varying conditions of humidity and temperature. Equations were also found that characterize the important cable and probe design quantities

Laser-optical blade tip clearance measurement system

A laser-optical measurement system was developed to measure single blade tip clearances and average blade tip clearances between a rotor and its gas path seal in rotating component rigs and complete engines. The system is applicable to fan, compressor and turbine blade tip clearance measurements. The engine mounted probe is particularly suitable for operation in the extreme turbine environment. The measurement system consists of an optical subsystem, an electronic subsystem and a computing and graphic terminal. Bench tests and environmental tests were conducted to confirm operation at temperatures, pressures, and vibration levels typically encountered in an operating gas turbine engine

Studies on the turnover of glucocerebrosidase in cultured rat peritoneal macrophages and normal human fibroblasts

The kinetics of glucocerebrosidase synthesis and degradation in rat peritoneal macrophages and in human fibroblasts have been studied using conduritol B epoxide (CBE), an irreversible and specific inhibitor of mammalian glucocerebrosidase. In cultured fibroblasts, higher concentrations of CBE and/or longer times were required for inhibition of glucocerebrosidase than were necessary for inhibition of the macrophage enzyme. However, inhibition of activity in cell extracts from both cell types showed identical time and concentration dependence. After the removal of CBE from cultures, enzyme activity returned to normal with a half-time of 48 h for macrophages and 40 h for fibroblasts. The reappearance of enzyme activity was prevented by an inhibitor of protein synthesis. Both the rate of synthesis and degradation of glucocerebrosidase enzyme protein were independent of the presence of CBE. The calculated rate of degradation of glucocerebrosidase was confirmed using metabolically labelled enzyme in cell cultures. The rate of synthesis for macrophages is 1.8 ng enzyme h-1 mg cell protein-1 and the rate of degradation is 1.4% h-1 (0.014 h-1). These values were 2.0 ng h-1 mg-1 and 0.018 h-1 for fibroblasts

Two-Color Laser Speckle Shift Strain Measurement System

A two color laser speckle shift strain measurement system based on the technique of Yamaguchi was designed. The dual wavelength light output from an Argon Ion laser was coupled into two separate single-mode optical fibers (patchcords). The output of the patchcords is incident on the test specimen (here a structural fiber). Strain on the fiber, in one direction, is produced using an Instron 4502. Shifting interference patterns or speckle patterns will be detected at real-time rates using 2 CCD cameras with image processing performed by a hardware correlator. Strain detected in fibers with diameters from 21 microns to 143 microns is expected to be resolved to 15 mu epsilon. This system was designed to be compact and robust and does not require surface preparation of the structural fibers