Abstract: A part circle metal frame having a mat secured thereto which is centrally foldable about a skid bar for catching shrub trimmings in an unfolded position beneath a shrub, for removing the shrub trimmings from beneath the shrub on the skid bar and for transporting the shrub trimmings to a refuge container with the frame and mat folded to form a pouch having a rigid frame.

Abstract: Resilient attachments are mounted on a feed auger of the type having a central drum mounted for rotation about a longitudinal axis, spiral flights mounted on longitudinal ends of the drum, and a central drum portion having a plurality of radially extending feed fingers. Each resilient attachment is mounted on and extends radially from the central drum portion about one of the fingers. During operation of the auger, the attachment prevents the accumulation of vegetation on the auger, improves feeding of the vegetation to the combine throat and protects the auger from damage.

Abstract: This invention concerns improvements to procedures to splice yarns (20-21), whether textile yarns or otherwise, the splice being obtained by coupling two single untwisted yarns (20-21) and by reconstituting the twists thereafter, by which improvements a part of the single yarns (20-21) is untwisted until twists of a sign opposite to the sign of the original twists have been imparted, such part then being coupled and reduced tails (220-221) of yarns being obtained, the coupled tract then being retwisted until a required twist has been imparted, the improvements envisaging that the reduced tails (220-221) are obtained after the fibers to be plucked and/or torn (42) have been made substantially parallel and after a substantially axial plucking and/or tearing action has been applied to such fibers (42), and that the taper (320-321) of the remaining reduced tails (220-221) reaches the neighborhood of the periphery of retwister rings (28), the resulting remaining tails (220-221) being controlled and positioned besi

Abstract: An improved device to piece-up yarn and doff yarn packages on open-end spinning machines. The device comprises a carriage (12) equipped with specific means for the tasks of piecing-up yarn and doffing yarn packages, said carriage being supported cantilever-wise by an arm (13) secured to a trolley (15) able to run on lengthwise guides (17), said carriage (12) being equipped with an arm (20) to hold tubes which cooperates with a store (18) of tubes.

Abstract: A method for starting the operation of a friction spinning machine, including friction surfaces movable in opposing directions for forming a spinning wedge; the friction surfaces being movable in a spinning direction during a spinning operation, a device for supplying fiber to the spinning wedge, at least one suction device acting on the spinning wedge, a suction tube supplied with suction air, and a thread withdrawal device includes:stopping the fiber supply and the motion of the friction surfaces;stopping the suction;moving the suction tube through the spinning wedge in a given direction for sucking in thread and fiber remains;subsequently sucking a thread through the suction tube; moving the suction tube out of the spinning wedge in a direction opposite said given direction depositing the thread in the spinning wedge;resuming the suction at least as late as the step of moving the suction tube out of the spinning wedge;moving the friction surfaces in a direction opposite the spinning direction removing the

Abstract: A false-twisted polyester yarn of good dyeing and mechanical properties is produced by a process wherein a yarn consisting of an as-spun polyester fiber having a mean birefrigence index (.DELTA.n) of from 15.times.10.sup.-3 to 150.times.10.sup.-3 is heat-treated and continuously, subjected to a false twisting treatment or draw-false twisting treatment. A preferred apparatus used comprises a feed yarn creel, a false twisting heater and an optional stabilizing heater, a false twisting element and a winder, wherein a heat-treating heater of the non-contact type is arranged upstream of the false twisting heater and between the false twisting heater and the feed yarn creel, at a height substantially equal to the height of the feed yarn creel so that the heat-treating heater confronts the false twisting heater; and a yarn cooling zone is provided between the heat-treating heater and the false twisting heater.

Abstract: An arrangement for open-end friction spinning is disclosed having two adjacently arranged friction rollers driven in the same rotational direction forming a yarn forming wedge shaped gap or slot. A fiber opening device is provided for opening fibers to be spun and a fiber feed channel guides the fibers from the opening device to the yarn forming gap. A yarn withdrawal device is provided for drawing off the produced yarn in the direction of the longitudinal extension of the yarn forming gap. The opening device is configured to simultaneously treat a plurality of fiber bands and the fiber feed channel is divided into several sections in its cross section. The mouths of the feed channel sections are disposed to open to the yarn forming gap at least partially one behind the other along the longitudinal extension of the yarn forming gap.

Abstract: Open end friction spinning apparatus is provided in which there are one or more spinning units with respectively two adjacently arranged rollers, rotating in the same direction, and disposed to form a wedge shaped gap therebetween for accepting fibers and spinning them into a thread of yarn. A housing is provided for each spinning unit, which housing includes a stationary housing part carrying bearing devices for the rollers and a hingedly mounted cover type housing part connected at a pivot axle. The cover type housing part carries at least a part of a feeding channel for feeding fibers to the rollers to be spun.

Abstract: A fiber control apparatus in an open-end spinning frame is disclosed. According to the invention, in an open-end spinning unit having a fiber passage through which fibers opened by the combing roller are carried into the spinning chamber of the rotor, one or more nozzles are provided in the unit, each nozzle having an outlet opening located adjacent to the fiber outlet opening of the fiber passage so that one or more streams of jet air, emitted from the nozzle or nozzles, direct and guide the fibers introduced into the chamber toward the interior peripheral surface of the spinning chamber of the rotor, thus causing the fibers to reach said surface immediately without being slowed or bent by ambient air streams within the chamber. Consequently, formation of yarn having bent or randomly attached fibers is substantially prevented, whereby the strength and quality of the spun yarn is greatly improved.

Abstract: A novel drain system for venting excess fuel from the fuel pump of a jet engine, and particularly the augmenter pump of a jet engine afterburner, is described which comprises a drain line connected at a first end to the vent valve of the fuel pump and at a second end to the main fuel supply line for the engine, for draining the excess fuel from the pump to the main fuel line, a check valve in the drain line near the second end thereof for restricting fuel flow through the drain line in a direction from the first end to the second end, and a vent line having a restriction therein defining an orifice of predetermined size connecting the drain line to an overboard dump port open to ambient.

Abstract: A control apparatus for a gas turbine engine comprises an accelerating condition detecting mechanism and an operating speed control mechanism. The accelerating condition detecting mechanism detects the degree of acceleration in the engine. The operating speed control mechanism controls, depending upon the degree of the acceleration, the speed for opening variable nozzles installed in the inlet portion of a power turbine of the engine, and/or variable inlet guide vanes installed in the inlet portion of a compressor of the engine.

Abstract: A four-ported dump combustor is designed for use with a ramjet engine and ovides high combustion efficiency and pressure recovery for length-to-diameter (L/D) ratios of between 1.3 and 4.4, over a range of operating conditions.

Abstract: An air cooled exhaust valve provided primarily for use with an internal combustion engine, or the like. The valve is of the type having an elongated stem and an enlarged head formed at one end of the stem. The stem is axially slidably mounted within a housing while the enlarged valve head cooperates with a valve seat in the housing. A fluid passageway in the housing is connected at one end to a source of pressurized air and at its other end is open to the valve stem adjacent the valve head so that pressurized air flows axially down along the valve stem and across the valve head to cool both the valve head and stem.

Abstract: An exhaust system control apparatus for the exhaust of an internal combustion engine which is particularly useful on two-cycle engines. The exhaust system includes a subsidiary chamber connected to the normal engine exhaust passage with a valve for opening and closing communication between the chamber and exhaust passage to change the pressure wave at the engine cylinder exhaust port to provide optimum performance at high and low speeds. The chamber valve is operated rapidly by a pneumatic actuator supplied with compressed air from one or more of the sources disclosed, namely, a belt driven or electric air compressor and piston and cylinder devices extending between or forming the suspension components of a two wheeled vehicle. A pneumatic valve is operated by engine speed sensing means to supply or release the pressurized air to the actuator at a predetermined engine speed.

Abstract: A hydraulic drive system includes a pump and averaging accumulator for providing a source of substantially constant pressure hydraulic fluid for reciprocal movement of a piston within a cylinder to move a load such as a sawmill carriage attached to the piston, and a high pressure braking accumulator operable to receive and hold hydraulic fluid under a pressure higher than the pressure of the pump discharge and of the averaging accumulator to conserve energy during deceleration of the piston and load at each end of the piston stroke. The high pressure fluid stored in the braking accumulator during braking is employed to rapidly accelerate the piston and load at the beginning of each subsequent stroke, and a bypass circuit and relief valve may be provided between the accumulators to convey fluid to the averaging accumulator for further conservation of energy upon excessive build up of pressure in the braking accumulator.

Abstract: The invention relates to an improvement in internal combustion engines equipped with a compressor for the feeding air, according to which the intake duct is equipped with a heat-exchanging element for cooling the air when the latter is compressed to a comparatively high pressure.

Abstract: The present invention relates to the recovery of heat and/or condensable liquid from a gaseous environment utilizing an open cycle heat pump system. The open cycle heat pump system is employed to alter the temperature of a gas by compression, expansion, heat exchange, and combinations thereof, to condense selected vapors carried in the gaseous environment for removal from the gas. The open cycle heat pump system can also be used to extract the heat from a gas for use as desired.

Abstract: A servicing device is shown for recovering and charging refrigerant in a cooling system of the type having a compressor for circulating compressible refrigerant in a closed, pressurized system between a condenser and an evaporator to provide a cooling effect. The servicing device includes a storage container which has a fill port which is adapted to be connected by a fluid conduit to the closed, pressurized system being serviced. Heat exchange coils located within the container are cooled by a heat exchange system to create a low pressure atmosphere within the container and draw refrigerant from the closed, pressurized system into the container. The heat pump system has reversible valves to reverse the flow of auxiliary refrigerant being circulated through the system.

Abstract: In a Stirling refrigeration system in which a displacer is driven in a reciprocating motion within a cold finger by a pressure differential between helium gas in the cold finger and helium gas in a gas spring volume, the reciprocating piston compressor for the working volume has a clearance seal between the working volume and a control volume. The only lubricant in that seal is the helium gas. The mean pressure of the working volume relative to the control volume can be controlled by varying the length of the clearance seal throughout the stroke of the piston. Preferably, the seal is between alumina ceramic sleeves. The clearance seal compressor may also be used in a Gifford-McMahon cycle.

Abstract: A refrigerator having a reversible cold air meat keeper for providing convenient access thereto regardless of the side of the refrigerator that the doors are hinged. The cold air is channeled into a plenum behind the back wall of the refrigerator compartment and there are at least two spaced ports communicating from the plenum into the chamber. The cold air meat keeper has a conduit extending from the rear wall thereof. In one predetermined mounting position of the meat keeper, the conduit removably couples with one of the ports for receiving cold air from the plenum. In the alternate predetermined mounting position of the meat keeper, the conduit removably couples with the other port for receiving cold air.

Abstract: A protective capacity control system and method for controlling the capacity of a refrigeration system are disclosed. The protective capacity control system receives electrical input signals indicative of operator selected settings and refrigeration system operating parameters. These input signals are processed to generate a control signal which is a step function, preferably having two steps, of the temperature difference between a desired set point temperature and the sensed temperature of a heat transfer fluid cooled by operation of the refrigeration system. The capacity of the refrigeration system is reduced at a first effective overall rate to provide capacity control which will reduce hunting by the capacity control system when the sensed temperature of the heat transfer fluid cooled by operation of the refrigeration system is less than a lower limit of a selected temperature deadband relative to the desired set point temperature.

Abstract: A capacity control device for a variable displacement compressor in a refrigerating or air conditioning system is disclosed. The capacity control device controls the operation of a variable displacement device having two variable displacement valves for changing the capacity of the compressor as a function of the required refrigerating capacity of the air conditioning system. The capacity control device determines whether the compressor should operate at a high, medium or low capacity. If the required refrigerating capacity is smaller than the current capacity of the compressor, the capacity control device actuates the variable displacement device to enable the compressor to operate at a lower capacity. If the required refrigerating capacity is larger than the current capacity of the compressor, the capacity control device actuates the variable displacement device to enable the compressor to operate at a larger capacity.

Abstract: A vibration isolator is disclosed to mount a cryopump expander module or other vibrating equipment on a vacuum housing. The isolator includes a welded metal bellows which both forms a vacuum-tight passage and acts as an isolating spring, and a plurality of elastomeric isolators which clamp the oscillations of the bellows.

Abstract: An automotive air conditioner has an air duct in which a refrigerant evaporator of a refrigeration cycle is disposed in fluid-flow communication with a variable capacity refrigerant compressor driven by an automotive engine and provided with compressor displacement varying members. A blower is provided to cause air to flow through the evaporator and through the duct into the passenger compartment. A sensor is provided to detect a condition representing the cooling operation of the evaporator, such as the air temperature downstream of the evaporator, surface temperature thereof or the pressure of the refrigerant at the evaporator. An electric controlling circuit is operative in response to signals from the sensor to actuate a servo motor which in turn drives the compressor displacement varying members whereby the capacity of the compressor is varied in accordance with the condition detected by the sensor.

Abstract: An apparatus for continuously freezing liver pieces which comprises a freezing box having an inlet and an outlet, a conveyor movable from the inlet to the outlet of the freezing box and having a mesh belt, a number of nozzles provided laterally through the box at the upside of the mesh belt of the conveyor for blowing gaseous helium, a supplying guide portion formed at the head of the inlet at the upside of the mesh belt for supplying and placing the liver pieces, a rotatable roller journaled at the striking-off and exhausting portion disposed inside the striking-off and exhausting portion at the head of the outlet at the upside of the mesh belt in an outside contacting state laterally of the mesh belt, the roller having a number of striking-off projections projected from the surface thereof for striking-off the frozen liver pieces on the mesh belt by the insertion of the projections into the mesh belt.

Abstract: A device for selecting the needles on the dial plate of single cylinder circular knitting machines for the manufacture of ribbed fabric, said device comprising a coaxial sleeve secured on top of the dial plate and revolving with the dial plate and, as many swinging elements or jacks as there are needles on the dial. Each jack slides in a vertical groove which is defined in the sleeve and which coincides with a needle groove in the dial. Slides are selected to vertically displace the jacks from an operating position into a rest position. A pinned drum controls selectors and cams to control the swinging motions of the jacks when they are in operating position in order to control the radial displacements of the corresponding needles by means of the thus operated jacks.

Abstract: Knitting machine having two needle beds in which loop-forming knitting needles are mounted for extension and retraction, having disk cams disposed on a revolving drive shaft with an angular offset for the purpose of lifting the knitting needles, and having a patterning apparatus for engaging and disengaging the knitting needles and the cams according to the pattern, such that only engaged knitting needles can be raised by the disk cams, a transfer device being provided, which is intended for the transfer of loops formed on knitting needles of at least one needle bed to associated knitting needles of the other needle bed. This transfer device can control the coupling produced by means of the patterning apparatus between the disk cams and the knitting needles such that the knitting needles can be extended selectively by the disk cams into a knit position or into a transfer position (FIG. 1).

Abstract: The washing efficiency of removal of cooking and bleaching chemicals from cellulose paper pulp on horizontal belt washing filters is improved by disrupting the filter mat adjacent the belt intermediately of soft, displacement wash liquor applications to the filter mat topside. The objective may be achieved by directing a line of low volume, high pressure jets of filtrate or wash liquor against the belt underside. Alternatively, sonicly vibrated foils extended transversely of and adjacent to the belt are effective to disrupt the filler mat pursuant to the invention objective.

Abstract: A security lock box includes a receptacle having an access opening and a hinged door. A vertical door edge adjacent th hinge is provided with an edge return which engages an inwardly curved lip along the receptacle opening for preventing entry through removal of a hinge pin. The door additionally has flanges extending transversely along top and bottom edges. The flanges are adapted for cooperative interfitting within confronting guard recesses along the margin of the receptacle opening. A locking mechanism having a pair of selectively slidably locking bars is positioned within the access opening. The locking bars are extendable through slots within the door flanges for securing the door in a locked mode. The locking mechanism is activated by a cylinder lock mounted in the door. The cylinder lock includes a cylindrical housing for accommodating a removable key plug and operating key adapted for interchangeable applications within a plurality of similar lock cylinders.

Abstract: A cylinder lock which comprises a housing and, rotatably accommodated therein, a cylinder having an axially extending key slot for reception of, and rotation by, a mating key to unlock the lock. The cylinder is provided on at least one of its ends with an end plate having a similar key slot cut therethrough and means for removably attaching the end plate to the cylinder with the key slot of the end plate in register with the key slot of the cylinder to permit insertion, through the end plate, into the cylinder, of the key, whereby in case of a broken key, the end plate can be removed from the cylinder, thereby exposing a portion of the broken key, facilitating extraction thereof.

Abstract: A thin metal strip is made by hot-rolling a strip workpiece, stretch-bend leveling the hot-rolled strip workpiece immediately after hot-rolling it, tensioning the strip workpiece with a predetermined tension while stretch-bend leveling it, and thereafter coiling up the workpiece. In addition the workpiece is rapidly cooled immediately after stretch-bend leveling it and before coiling it up. Thus the workpiece is stretch-bend leveled before it cools so it can be treated while still about 1100.degree. C., at which temperature it is still very plastic. The workpiece can therefore be deformed greatly while under modest tension, so as to produce a very thin product that is very uniform. The tension in the strip merely serves to keep the workpiece looped over as much an arc as possible around the stretch-bending rolls.

Abstract: A crankshaft rolling machine includes a pair of model crankshafts mounted for synchronous rotation. One or more crankshaft rolling units are coupled to the model crankshafts in a manner enabling adjustment of the units along a linear path to adapt the device to the stroke length of a crankshaft to be rolled. The apparatus may be rapidly changed for rolling of crankshafts having different stroke lengths by linearly sliding the individual rolling units relative to the model cranks and thereafter locking the individual rolling units to the model cranks at positions corresponding with the stroke length of the crankshaft to be rolled.

Abstract: A hole sizing tool uses a swaging tap to move material which deforms the sides of a generally cylindrical hole toward the axis of the cylinder and is followed by a portion of the tool having a generally flat flaced helical spiral configuration with the turns increasing in radius as the tool advances but with all portions of the surface of the helical spiral including lines parallel to the axis of the tool whereby only radial forces are exerted by said portion to force the sides of the hole gradually toward a final diameter larger than that left by the tap but smaller than the original dimension. In an alternate form of the tool the flat surfaces of the helical spiral are inclined slightly, so that the edge of such surface nearest the nose of the tap is at a slightly greater radius than the edge of the turn nearest the tool in which the tap is held, to generate a slight axial force tending to pull the tool into the work.

Abstract: Disclosed is a rolling mill in which an intermediate roll is interposed between a work roll and a backup roll and is offset by a suitable distance in the direction of the rolling line. A horizontal bending force is exerted to the intermediate roll so that the flatness of the rolled product can be controlled with a higher degree of accuracy.

Abstract: A rolling mill is disclosed in which, in order to improve the quality of rolled products, a work roll with a small diameter is used and is offset by a predetermined distance from the reduction line and the horizontal bending force is exerted to the small-diameter work roll through a horizontal intermediate roll from a sectionalized roll so that flatness of a workpiece being rolled is controlled. The small-diameter work roll, the horizontal intermediate roll and the sectionalized roll are so arranged that their axes are maintained in coplanar relationship with each other. Therefore the axes of these rolls can be automatically aligned with a high degree of precision.

Abstract: In an electron beam lithography apparatus a capacitance height gauge is used to determine the distance between a reticule and electron optics. In order to calibrate the capacitance gauge an optical interferometer, including a mirror are mounted on the same axis as the capacitance gauge. The mirror is moved a predetermined distance so that the movement distance measured by the capacitance gauge and the interferometer can be compared.

Abstract: A method and apparatus for testing packages for leaks. Selected values of suction and positive pressure are supplied to a testing position, which may be a test head. A package to be tested is held in the testing position by the suction, and positive pressure is introduced into the package through a puncture, which may be made before or after the package is placed in position. Values of suction and positive pressure are chosen such that a package meeting leakage specifications will contain sufficient positive pressure to overcome the suction, causing the package to be ejected from the testing position. If the package does not meet specification, leakage will cause the suction to hold the package in position. Thus, a rapid and visible indication of package quality is provided.

Abstract: A viscosimeter measures the viscosity of a fluid, such as a petroleum hydrocarbon liquid, by driving a capillary through the fluid and measuring the pressure drop across the capillary. The viscosimeter comprises a pressure cylinder, a piston within the cylinder having at least one capillary tube, and an arrangement for driving the piston at a known speed so that the fluid is displaced at a known volumetric rate through the capillary tube. Pressure sensors on either end of the cylinder measure the capillary pressure drop. In a preferred embodiment, the piston has a main body and a selector plate. The main body has a plurality of capillary tubes each of a different bore size, and the selector plate is rotatable relative to the main body by rotating a selector handle outside the cylinder. An oven enclosure permits the cylinder, and its fill of fluid, to be heated in an air bath to reservoir temperatures.

Abstract: The invention comprises a device which performs the functions of both a Mooney Viscometer and an Oscillating Disk Rheometer to measure the visco-elastic properties of rubber and rubber-like materials. Rotational and oscillating motion are transmitted to a shaft by means of a sprocket and a hub connected to an eccentric. Rubber samples having a wide range of stiffnesses can be accommodated by a provision for changing the thickness of the sample.

Abstract: An inspecting liquid is dropped onto a resist layer formed on a gravure printing plate and is allowed to permeate the resist layer or gelatin resist layer to reach the printing plate so that a short circuit is formed between the inspecting liquid and the printing plate. The time required for forming the short circuit in the resist layer is measured by utilizing an oscillator pulse counting circuit to determine the conditions of the resist layer thereby to improve the quality of the finished printing plate.

Abstract: A method of identifying a parameter of a model for a rate of loss of boiler efficiency due to a sootblowing operation, in a boiler having a plurality of heat traps, comprises measuring a time since a last sootblowing operation in the heat trap in question, measuring an overall boiler efficiency at the beginning of sootblowing for the heat trap in question, measuring a change in efficiency due to the sootblowing operation and calculating the parameter using an equation. According to the equation, the ratio of efficiency change over overall boiler efficiency equals the time factor since the last sootblowing operation times the parameter minus a summation of factors for each of the other heat traps and their associated sootblowing operations. The technique is extendable to individual sootblowers within a heat trap by using fouling rate index rather than overall boiler efficiency.

Abstract: A method of diagnosing the peak compression pressure and power output of individual cylinders of an internal combustion engine based on stored normalized energy coefficients derived from a normalized pressure curve and the measured instantaneous engine speed.

Abstract: A spray pattern analyzer for use in analyzing spray patterns formed by spray nozzles which are attached to an agricultural spray applicator boom. This analyzer includes a corrugated collector tray mounted on a cart. The cart has wheels for moving the collector tray through the spray pattern. The collector tray is designed so as to receive collector test tubes each being longitudinally aligned with the troughs of the collector tray. When the troughs are partially filled with spray, the collector tray is tilted so that the spray will flow into the test tubes to provide a visual indication of the pattern. The collector tray is constructed in segments to allow the collector tray to be collapsed. Further, the cart is constructed to permit an adjustment of the height of the collector tray from the surface upon which the cart rests.

Abstract: A combination altimeter and vertical speed indicator using digital displays. Digital logic technique are used to calculate vertical speed, eliminate drift in the vertical speed zero indication, correct vertical speed readings for altitude, and display altitude below zero. An automatic reading of barometric pressure setting for use as an offset is furnished at turn-on to permit initial setting of the instrument. Power to the instrument is pulsed to reduce consumption and permit long term battery operation.

Abstract: An improved meter vault cover having a window-like access for externally viewing and reading the internal register of liquid or gas passing through the meter is provided. The improved meter vault cover not only provides the window-like opening but also provides a carriage-like support on the inside of the cover to hold a digital readout device to serve as the register. The digital figures of the readout device are projected and exhibited at the window-like access for making the register externally visible. The improved meter vault cover consists of a meter vault cover plate, a worm-type cover locking screw, a register support carriage with suitable screws for affixing the carriage to the cover, and a register device with suitable wiring to connect it to the meter.

Abstract: Device for fatigue-testing a mechanical component by exciting this component (1), to which massive armatures (2, 3) may be attached, using an electromagnetic vibrator (13) fed by a generator, characterized in that the said generator comprises a displacement sensor (14) placed between two parts of a vibrating assembly (1, 2, 3) and generating a sinusoidal signal; a root-mean-square value converter (5) converting this alternating signal into a direct current signal of root-mean-square value; and an analog divider circuit (7) receiving the sinusoidal signal as numerator (8) and the root-mean-square value signal produced by the said converter as denominator (6), with the output signal (9) from this divider (7) being used after amplification (12) to drive the electromagnetic vibrator (13) acting on the vibrating assembly.

Abstract: An ultrasonic corrosion monitor is provided which produces an in situ measurement of the amount of corrosion of a monitoring zone or zones of an elongate probe placed in the corrosive environment. A monitoring zone is preferably formed between the end of the probe and the junction of the zone with a lead-in portion of the probe. Ultrasonic pulses are applied to the probe and a determination made of the time interval between pulses reflected from the end of the probe and the junction referred to, both when the probe is uncorroded and while it is corroding. Corresponding electrical signals are produced and a value for the normalized transit time delay derived from these time interval measurements is used to calculate the amount of corrosion.

Abstract: A method or system for measuring thickness of a coating layer on a substrate. It employs acoustic energy and involves transmitting a sweep of frequencies covering a predetermined range through the substrate and its coating. The energies reflected back by the substrate and coating are determined as a function of the frequencies in said range, and the transmission pattern provides a basis for determining the coating thickness.

Abstract: The grain size is expressed by the diameter of grains demarcated at high-angle grain boundaries, such as ferrite grains in ferritic steels. Ultrasonic waves having a frequency f are propagated through an object to be examined and its attenuation constant .alpha. is determined. Using the ratio f/.alpha. and equationC'.sub.j .ltoreq.f/.alpha..ltoreq.C'.sub.j+lwhere C'.sub.j and C'.sub.j+l are constants and j is a constant between 1 and 4, the order j of the region to which the value of f/.alpha. belongs is determined. Then the grain diameter D is derived from equation ##EQU1## using an integer n.sub.j and constant A.sub.j predetermined for the order j of each region.

Abstract: A transducer assembly comprising a transducer housing, a retainer mounted on the housing for generally axial movement relative to the housing and a collar for relatively moving the retainer and the housing along the path between a locking position and a releasing position. The transducer assembly also includes a dome which is coupled to the housing by cooperating lugs and retaining flanges on the dome and the retainer, respectively.