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Figure G.22. Figure G.23. The microstructural changes, aside from the scale of damage, were consistent for all specimens. Figure G.24. As can be seen from Figure G.24, their orientation is such that they could increase the susceptibility to fatigue crack growth.. Figure G.25 is a back-scattered electron image showing an area of the edge of a V-notch produced by firing...
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0.22 mm 0.96 mm. 0.40 mm 0.18 mm. 1.00 mm 0.33 mm. 0.36 mm 0.12 mm. 0.27 mm 0.39 mm. Figure G.34. The failure of the fine mesh to better predict material failure indicates that advanced codes such as hydrocodes and Particle-In-Cell (PIC) methods require significant expertise in order to be used correctly. In this case, the poor predictions may...
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residual stresses assumed present in ballistic and solenoid simulated FOD with compressive zone of 0.004 inches. First, assume an FOD event has occurred on the leading edge of a blade resulting in a notch with a depth of 0.3 mm (0.012 in). The notch has a root radius of 0.06 mm (0.0024 in.) and does not have a crack emanating...
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Blades insufficiently designed for FOD considerations have caused In-Flight Shut Downs (IFSDs) and costly damage to the engine. FOD tolerance can be enhanced by use of more damage tolerant materials and a redistribution of the blade mass.. The requirements of 3.3.2.2 shall be verified by:. “Simulated foreign object damage shall be applied to the (a) critical stage blades at one...
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Following the post-test performance check, the engine shall be disassembled to determine the extent of sand erosion, and the degree to which sand may have entered critical areas in the engine.. The recommended text decreases the operational time in the extreme sand and dust environment from ten hours to two hours for turbofan and turbojet engines. Engine contractors have been...
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All of the components of a motion control system must work together seamlessly to perform their assigned functions. Most motion control systems today are powered by electric motors rather than hydraulic or pneumatic motors or actuators because of the many benefits they offer:. The output of the ampli- fier causes the motor to speed up or slow down to correct...
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The programmability of the industrial robot using computer software makes it both flexible in the way it works and versatile in the range of tasks it can accomplish. Robots can be floor-standing, bench- top, or mobile.. There is no common agreement on or stan- dardizations of these designations in the literature or among robot specialists around the world.. These designations...
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A part with its open-end facing to the right (part 1) falls on a matching projection as the indexing wheel begins to rotate clockwise. The parts come down the chute with the bottom of the “U” facing either to the right or left. Pin 1 now moves into the passage way, and if the bottom of the “U” is facing...
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As the input gear rotates, it also pulls the chain around with it, producing a At the end of 180º rotation of the. Brown of the Engineering Research Division, Scott Paper Co.. These mechanisms, moreover, can function as phase adjusters in which the rotational position of the input shaft can be shifted as desired in relation to the output shaft....
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The ball cage ensures the proper spacing of the balls and its contacting surfaces are hardened and lapped.. Adjustments are neces- sary to prevent looseness of the slide. The linear motion of the screw is translated into the rotary motion of a ball nut. The screw pitch is selected so that the revolutions of the flywheel represent the distance the...
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Constant force is approached because of the length of this U-spring. Easy positioning of the slide is possible when the handle pins move a grip spring out of con- tact with the anchor bar.. This volute spring lets the shaft be moved closer to the frame, thus allowing maximum axial movement.. This cushioning device imparts rapid increase of spring tension...
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They are pin-jointed at the instantaneous centers of curvature, 1 and 2, of the contacting surfaces. With any change in relative positions, the points 1 and 2 are shifted and the links of the equivalent mechanism have different lengths.. 1 Basic cam mechanism and its kinematic equivalent (points 1 and 2 are centers of curvature) of the contact point.. ticity...
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addendum circle: The circle defining the outer diameter of the gear.. It is also the sum of the tooth thickness and the space width, measured in inches or millimeters.. contact ratio: The ratio of the number of teeth in contact to the number of those not in contact.. diametral pitch (P): The ratio of the number of teeth to the...
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3 This crossed-axis yoke coupling is a variation of the mecha- nism shown in Fig. A tilt in the central member can occur because of the off- set of the slots. Parallel-link connections between disks (see upper drawing) exactly duplicate the motion between the input and output shafts—the basis of this principle in cou- pling. The lower diagrams show three...
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As the boom is raised or lowered, the cam shifts the position of the reed switches so they will come into close proximity with the magnet on the pointer and, sooner or later, make contact. The timing of this contact depends partly on the movement of the pointer that carries the magnet. When the magnet contacts the reed switches, the...
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PUMPING ACTION is produced by the meshing of the idler and rotor teeth in this rotary pump. The action of the buckets, fitted loosely into recesses in the rotor, compensates for wear. In oper- ation, the tip of the bucket is in light con- tact with the casing wall. HIGH-PRESSURE, high-volume pumps of the axial piston, constant displace- ment type...
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The mechanism employs four cam/gear assemblies, one at each corner of the lower plate. The gears on each side of the plate face inward to balance the loading and help align the plates. gears on the cam-gear assemblies are connected to a common drive motor.. Further rotation of the worm gear shortens the hook extension and raises the lower plate...
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FOUR-BAR LINKAGES—Two cranks, a connecting rod and a line between the fixed centers of the cranks make up the basic four-bar linkage. CRANK AND ROCKER—the following relations must hold for its operation:. Point T describes a line perpendicular to the parallel position of the cranks.. PARALLEL CRANK FOUR-BAR—Both cranks of the parallel crank four-bar linkage always turn at the same...
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For example, CAD techniques now available can perform analysis and simulation of the design as well as generate manufacturing instructions. These features are being integrated with the code for modeling the form and struc- ture of the design.. Each view of the object is created independently from other views. Unless careful checks of the finished drawing are made, mistakes in...
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A correct profile of the disk half in the. The reason for using a flexible gate is to prevent binding of the gate within the valve when the valve is in the closed position. If a solid gate fits snugly between the seat of a valve in a cold steam system, when the system is heated and pipes elongate, the...