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Fault-finding
Published in Chris Stacey, Practical Pneumatics, 2012
Flow meters and tachometers are required mainly for work on compressors and motors. The typical flow meter is a glass cylindrical coupling for insertion into the pipeline with a moving piston to indicate the flow in litres/min. This enables the output of a compressor to be checked, changed by calculation into free air and compared with the rated performance. The driven speed of the compressor is that of the driving motor, but if this is in doubt, a tachometer enables it to be checked. The typical tachometer is a battery powered hand-held torch-like instrument with a digital display and photoelectric send-receive device which when pointed at a reflective spot (tape fixed beforehand or a painted spot) on shaft or coupling gives an accurate read-out in rpm. By this process, together with a pressure gauge in the delivery line, it is also possible to test a motor running free or perhaps working under load.
Fault–finding
Published in Chris Stacey, Practical Pneumatics, 2011
Flow meters and tachometers are required mainly for work on compressors and motors. The typical flow meter is a glass cylindrical coupling for insertion into the pipeline with a moving piston to indicate the flow in litres/min. This enables the output of a compressor to be checked, changed by calculation into free air and compared with the rated performance. The driven speed of the compressor is that of the driving motor, but if this is in doubt, a tachometer enables it to be checked. The typical tachometer is a battery powered hand-held torch-like instrument with a digital display and photoelectric send-receive device which when pointed at a reflective spot (tape fixed beforehand or a painted spot) on shaft or coupling gives an accurate read-out in rpm. By this process, together with a pressure gauge in the delivery line, it is also possible to test a motor running free or perhaps working under load.
The Instrumentation and Automatic Control of Cold Rolling Mills
Published in William L. Roberts, Cold Rolling of Steel, 2017
Where a high order of accuracy is required, digital tachometers are used. These take a variety of forms but all provide a sequence of voltage impulses (the recurrence frequency being directly and accurately related to rotational speed), and have the advantage of not using slip rings. For lower speed applications, magnetic or electromagnetic units may be used. In the case of the former, a wheel with small magnets embedded in its periphery may be used with a reed type switch shown in Figure 5-10. In the case of the latter, however, a detector that senses the proximity of metal may be used in conjunction with a gear wheel or similar rotational unit. For higher frequency operations, optical systems may be used, as illustrated in Figure 5-11.
Parabolic tapering piezoelectric rotational energy harvester: Numerical analysis with experimental validation
Published in Mechanics of Advanced Materials and Structures, 2023
Rakesh Ranjan Chand, Amit Tyagi
The brass host is tapering parabolically from one end to the other, as shown in Figure 5a. The parabolic host beam is cut in the Wire EDM machine by creating more than 200 key-points for each side using the coordinate expressions p1(0,0), p2(x, y(x)), p3(x, [b0 - y(x)]), and p4(0, b0) as demonstrated in Figure 1. The piezoelectric patches are surface-bonded on the brass host, as shown in Figure 5b. The PZT-5H patches used in the experiment are from MIDE Technology Corporation, USA. A block of mild steel is fixed at the free end of the harvester to act as the tip mass. A regulated DC power supply (METRAVI RPS-3010) is used to regulate the speed of the motor (Revolution Technology, HSN/SAC 39219010), which drives the shaft. Through a coupling, the shaft is connected to the motor. A tachometer is used to measure the rotating speed of the shaft. The tapered harvester is attached to the shaft using a cross hub. Through a slip ring (Lepakshi Enterprises, Model-B0713ZRG3), the generated voltage from the harvester is transmitted. Finally, the AC output signal is analyzed using a digital storage oscilloscope (GWINSTEK, Model-GDS1054B). The peak open-circuit output voltage from the harvester is measured for driving frequencies ranging from 0.7 Hz to 20 Hz. The complete experimental setup for harvesting rotational energy and producing electrical voltage is shown in Figure 6.
In-Motion Railroad Tie Deflection Measurement via Ultrasonic Airborne Sonar and Computer Vision Techniques
Published in Research in Nondestructive Evaluation, 2023
Ali Zare Hosseinzadeh, Diptojit Datta, Francesco Lanza di Scalea
where, wi,r and wi,j are the received waveforms from the reference and the jth transducer, respectively, at the ith point flagged as tie. Also, * denotes the cross-correlation operator. By computing the relative deflections at the probed points (by means of Equation (2)), the 3D surface deflection of the ties can be interpolated according to a given spatial resolution. The spatial position of the sonar system can be tracked by means of a high-resolution tachometer. However, the precise position from a tachometer can often be erroneous due to several factors, such as wheel slippage. To increase the robustness of the positioning tracking system, we have also evaluated an image processing-based technique that precisely tracks robust features in successive pairs of images. This image-based position tracking technique was used in one of the field tests discussed in the next section.
Co-pyrolysis of Juliflora biomass with low-density polyethylene for bio-oil synthesis
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Midhun Prasad k, Murugavelh Somasundaram
The experiments were conducted in an auger reactor made of stainless steel. The length of the reactor is 1.49 m and width is 0.29 m, internal diameter of the tubular reactor is 0.16 m shown in Figure 1. A screw feeder inside delivers the feedstock. The reactor consists of mainly five components (1) feed hopper, (2) inconel tube which served as a reactor, (3) electrical furnace, (4) condensing column, and (5) control unit. Feed hopper delivers the biomass into the reactor. The hopper is designed to hold 8 kg of JF biomass, the conical shape helps in uniform flow of biomass. Tubular reactor has a capacity of 14 kg. The rotation of the screw helps in the movement of feed from the hopper to the end of the reactor. The screw feeder is coupled with a shaft on the both sides, one end is connected with the motor for the rotation of the shaft and the other end is fixed with a bearing to avoid vibration in shaft. Furnace acts as the source of heat. The tubular reactor is covered by furnace by its all sides and the edges are coated with heat-resistance material to avoid heat loss in the furnace. The coil present inside the furnace heats the walls of the reactor. Heat is transferred from the wall of the tubular reactor to the biomass. The vapor liberated from the reactor is condensed using a condensing column of 5,000 ml capacity. The condensation of volatile gas components is achieved by circulating chilled water at 10°C. The reactor is supplemented with a control panel which consists of eight segment Proportional–Integral–Derivative (PID) controller made of siemens S7-1500, which helps for the fixing of temperature and heating rate for the reaction. A tachometer is provided for measuring theROTATION PER MINUTE (RPM) of the shaft. The temperature at various sections of the reactor is monitored using six k-type thermocouples of Emerson Rosemount 214°C temperature sensor.