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The purpose of the work is to propose methods and means for determining the technical condition of fuel equipment. A method is proposed for determining the technical condition of the high-pressure pump and injectors of the marine diesel MAN B&W 6S50MC-C by changing the maximum fuel pressure and temperature of the outer surface of the pipeline. For fuel equipment with a maximum pressure in the pipeline from 50 to 150 MPa, the permissible pressure change zone is determined. A formula is proposed that additionally takes into account the cyclic fuel supply and its mass when estimating the temperature from its compression by the pump plunger. The fuel temperature during compression is determined depending on the pressure value. The calculation of the heat transfer process through the pipeline wall and from the heated wall surface to the air is performed. A portable RGK PL12 pyrometer is proposed to measure the temperature on the pipeline surface and determine the technical condition of the fuel equipment. The permissible temperature change zone of the pipeline surface is given, according to which the serviceable condition of the pump and the nozzle is evaluated.

Infrared radiation thermometers (IRTs) overcome many of the limitations of thermocouples, particularly responsiveness and calibration drift. The main challenge with radiation thermometry is the fast and reliable measurement of temperatures close to room temperature. A new IRT which is sensitive to wavelengths between 3 μm and 11 μm was developed and tested in a laboratory setting. It is based on an uncooled indium arsenide antimony (InAsSb) photodiode, a transimpedance amplifier, and a silver halogenide fibre optic cable transmissive in the mid- to long-wave infrared region. The prototype IRT was capable of measuring temperatures between 35 °C and 100 °C at an integration time of 5 ms and a temperature range between 40 °C and 100 °C at an integration time of 1 ms, with a root mean square (RMS) noise level of less than 0.5 °C. The thermometer was calibrated against Planck’s law using a five-point calibration, leading to a measurement uncertainty within ±1.5 °C over the aforementioned temperature range. The thermometer was tested against a thermocouple during drilling operations of polyether ether ketone (PEEK) plastic to measure the temperature of the drill bit during the material removal process. Future versions of the thermometer are intended to be used as a thermocouple replacement in high-speed, near-ambient temperature measurement applications, such as electric motor condition monitoring; battery protection; and machining of polymers and composite materials, such as carbon-fibre-reinforced plastic (CFRP).

This article presents a new model of optical power gathered by a fiber-optic pyrometer when there is a tilting angle between the fiber longitudinal axis and the vector perpendicular to the tangent plane of the emitted surface. This optical power depends on the fiber specifications, such as the diameter and the numerical aperture (NA), as well as the object parameters, including its diameter, emissivity, and tilting angle. Some simulations are carried out using other pyrometers from the literature without tilting to validate the model. Additional simulations with different optical fibers, object sizes, and distances at different tilting angles allow us to describe the behavior of the pyrometer when the object is smaller than the optical fiber field of view (the light cone defined by its NA). The results show that for a finite surface object, the power collected by the optical fiber is affected by changes in the tilting angle, greater tilting lesser gathered power, and reaching the maximum power when the field of view of the fiber covers up the entire object, as expected. On the other hand, additional equations are presented to describe the maximum tilting angle, and distance that allow the maximum power gathered for a determined object diameter and fiber, avoiding temperature measurement errors.

A pyrometer with non-parallel sighting is developed, which allows simultaneously with temperature measurement to perform video surveillance of the control object. Pyrometer has optically connected lens, signal meter, thermostat in which radiation receiver is placed, and video camera. The front surface of the thermostat is polished, directed at an angle of 45 ° to the optical axis of the lens and has a hole that acts as a field diaphragm. Video camera is directed to polished surface of thermostat perpendicular to optical axis of lens. Pyrometer operation, its design and functional diagram are described.

Process online monitoring is a vital and integral part of high-speed laser scribing process in which speed and quality are paramount. In this study, a multi-sensory platform for real-time monitoring of the ultrafast pulsed laser engraving process has been developed. Four different sensors have been examined from various perspectives and the results have been analyzed and compared. The real-time monitoring system developed for this study consisted of IPG ytterbium pulsed fiber laser, scan head, illumination system, and four monitoring sensors, including a spectrometer, pyrometer, infrared (IR) camera, and high-speed camera. Various experiments were performed to evaluate the performance of the designed platform by applying each sensor to monitor a high-speed laser scribing process in real-time. The output of each sensor was analyzed by changing different laser and process parameters, such as laser power, focal position, beam speed, and pulse length. Strengths, weaknesses, and challenges of using each monitoring tool for the laser engraving process were discussed based on the obtained results.

The article discusses the issues of improving strainresistive pressure sensors (PS) for their joint use with modern achievements of fiber optics (FO). The possibilities of implementation and features of FO pyrometric compensation of the temperature error of semiconductor and resistive strain-resistor, optical and/or electrical heating of the strain gage for selfcalibration of the pyrometer, power supply by optical radiation transmitted through a light guide with galvanic isolation of the PS circuit, increased noise reduction and fire and explosion safety are considered. Noise properties of semiconductor and resistive strainresistor are also considered.

Perkembangan teknologi berbasis internet yang pesat menyebabkan terjadinya perubahan pada sektor industri yang dikenal dengan Revolusi Industri 4.0. Industri manufaktur pengecoran merupakan salah satu sektor industri yang harus beradaptasi dengan perkembangan industri 4.0 agar dapat bersaing dalam meningkatkan kualitas produk coran. Beberapa parameter yang mempengaruhi kualitas produk coran adalah temperatur saat penuangan (pouring) dan laju penuangan. Penentuan temperatur penuangan harus memperhitungkan faktor kehilangan panas yang disebabkan oleh waktu pemindahan logam cair dan kondisi lingkungan sekitar. Penentuan temperatur tuang yang kurang tepat dapat menyebabkan terbentuknya porositas (rongga) pada produk hasil pengecoran. Karena pentingnya penentuan temperatur tersebut, maka pada penelitian ini dibangun sistem monitoring berbasis internet of things (IoT) untuk memantau temperatur logam cair saat proses pengecoran secara real-time. Sistem yang dibangun terdiri atas tiga bagian, yaitu: sensor temperatur, gateway dan server. Perangkat pyrometer digunakan untuk mengukur temperatur logam cair dan mengirimkannya ke gateway. Perangkat gateway kemudian mengirimkan data tersebut ke server. Pengguna dapat mengamati temperatur logam cair secara real-time melalui website. Hasil penelitian menunjukkan bahwa dengan sistem monitoring berbasis IoT ini, dapat diperoleh database pengukuran temperatur logam cair yang optimal. Tingkat keakuratan pengukuran data temperatur tersebut mencapai 99,5%.

A linear pyrometer is used to realize the International Temperature Scale of 1990 (ITS-90) for temperature ranges above 961.78 °C in most National Metrology Institute (NMI) radiation thermometry labs. The different components of the linear pyrometer system working together to measure temperature may exhibit some errors which should be accounted for. The errors can be characterized by several equipment parameters that should be measured before the radiation thermometer is used to realize ITS-90 temperatures. Relative spectral responsivity (s), size of source effect (SSE), gain ratio (GR), non-linearity (NL), distance effect (DE), temperature coefficient and zero drift are all major equipment parameters that characterize the efficiency of a linear pyrometer in realizing ITS-90. In this work, an attempt was made to describe and demonstrate these major parameters by using actual measured characterization results of a linear pyrometer. Uncertainty contributions from some of the parameters considered in scale realizations was also demonstrated using the measurement results.

Accurate and high-speed transient surface-temperature measurements of combustion devices including internal combustion (IC) engines, gas turbines, etc., provide validation targets and boundary conditions for computational fluid dynamics models, and are broadly relevant to technology advancements such as performance improvement and emissions reduction. Development and demonstration of a multi-infrared-channel pyrometry-based optical instrument for high-speed surface-temperature measurement is described. The measurement principle is based on multi-spectral radiation thermometry (MRT) and uses surface thermal radiation at four discrete spectral regions and a corresponding emissivity model to obtain surface temperature via non-linear least squares (NLLS) optimization. Rules of thumb for specifying the spectral regions and considerations to avoid interference with common combustion products are developed; the impact of these along with linear and non-linear MRT analysis are assessed as a function of temperature and signal-to-noise ratio. A multi-start method to determine the MRT-solution global optimum is described and demonstrated. The resulting multi-channel transient pyrometry instrument is described along with practical considerations including optical-alignment drift, matching intra-channel transient response, and solution-confidence indicators. The instrument demonstrated excellent >97% accuracy and >99% 2-sigma precision over the 400–800 °C range, with ~20 µs (50 kHz, equivalent to 0.2 cad at 2000 RPM IC-engine operation) transient response in the bench validation.

The quality of the material deposition and contour accuracy produced by WAAM (Wire Arc Additive Manufacturing) depends on process parameters such as the temperature and the volume of the weld pool. The control of the welding process can be substantially improved by obtaining real-time signals of the weld-pool temperature and volume. In this paper, we present a new optical sensor that can measure the quantities through the welding arc. We have developed a ratio pyrometer with narrowband filters that suppresses the radiation from the plasma. We present our new sensor in this paper and demonstrate its capability to measure the weld-pool temperature pyrometrically and the weld-pool area by digital image processing as a real-time signal through the arc. In addition, we estimate the weld-pool volume from its area and the known material inflow.

The article presents the analysis of uncertainties associated with reliable accounting difficulties for the radiation coefficient in non-contact temperature measurement in industrial environment. Practical recommendations of methodological and instrumental nature to reduce such measurements errors are offered. On the Planck function and the aluminum reflection coefficient mathematical model basis the analytical aluminum radiation coefficient dependence on temperature and wavelength is obtained. Methodological errors estimates of low-temperature thermometers with a spectral sensitivity ranges equal to 7–14 and 3–5 µm are produced. Experimental studies are carried out using Optris CT LT15 pyrometer and Flir E60 infrared imager.

This paper describes the development of cutting temperature measurement of end mill tool by using infrared radiation technique approach. Compared to conventional thermocouple technique, infrared radiation technique is an advance method of measuring temperature which featured high accuracy, high response rate, wide range of temperature scale detection and almost compatible with all materials used in the manufacturing industry. We measures the emission of infrared radiation from the source, which is cutting edge of tool by using photocells that contains InAs and InSb photovoltaic detectors. Photocells converts the infrared radiation to a voltage signal and then recorded by oscilloscope followed with a calibration with its corresponding temperature. This paper discussed about the calibration method, cutting experiment setup, the limit of infrared radiation level detected by photocells, signal correction of output signal, and relations of peak signal formation with rotation of end mill tool. The developed pyrometer is also capable to profile the cutting tool’s rotation based on the movements of infrared radiation’s emission at cutting tool’s edge. The conclusion was that the measurement of cutting temperature of high speed machining by using infrared radiation technique is possible. The developed pyrometer are capable to detect temperature changes at a span of 0.01 ms.

The article deals with the use of jet-drop optical measuring systems (JDOMS) on machine tools for recording acoustic emission (AE) signals and pyrometric temperature measurement in the cutting zone. The work of JDOMS is considered on the examples of metal working with the supply to the cutting zone of cutting coolant directed by a jet or through the internal through-holes of the cutting tool. It is shown that the coolant flow is used for directional transmission from the cutting zone of AE signals to the hydrophone as a sound guide and light of the infrared range to the pyrometer as a light guide. In the first case, AE signals are recorded to control the metal working conditions in the cutting zone, and in the second case, its temperature is measured.

The uncertainty of emissivity has a major effect on the accuracy of a pyrometer in billet temperature measurement. In order to eliminate the influence of emissivity, we place a reflector with two apertures at the front of a pyrometer. The two apertures on the reflector are used to measure intrinsic radiation and approximate blackbody radiation of the billet. The radiation is collected by two infrared dual-band detectors in the pyrometer. Then, the real-time emissivity of the billet can be measured with no assumptions, so the influence of emissivity is eliminated. In addition, the measurement uncertainty is analyzed based on the ray-tracing method. The pyrometer is developed and the accuracy verification of emissivity is implemented. Compared with the reference material at the same temperature, the measurement errors of the emissivity are 0.021 and 0.005 at two wavelengths. Then, we install the pyrometer in the medium plate rolling process for measurement. Compared with a thermal imager used in the rolling process, the measurement fluctuation is reduced obviously. It indicates that the method of emissivity measurement is very effective for billet temperature measurement.

Measuring reliably the correct temperature of a sooty flame in an internal combustion engine is important to optimise its efficiency; however, conventional contact thermometers, such as thermocouples, are not adequate in this context, due to drift, temperature limitation (≤2100 K) and slow response time (~10 ms). In this paper, we report on the progress towards the development of a novel ultra-high-speed combustion pyrometer, based on collection of thermal radiation via an optical fibre, traceably calibrated to the International Temperature Scale of 1990 (ITS-90) over the temperature range T = (1073–2873) K, with residuals

In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining.

The modeling of laser-based processes is increasingly addressed in a competitive environment for two main reasons: Preventing a trial-and-error approach to set the optimum processing conditions and non-destructive real-time control. In this frame, a thermal model for laser heating in the form of non-penetrative bead-on-plate welds of aluminum alloy 2024 is proposed in this paper. A super-Gaussian profile is considered for the transverse optical intensity and a number of laws for temperature-dependent material properties have been included aiming to improve the reliability of the model. The output of the simulation in terms of both thermal evolution of the parent metal and geometry of the fusion zone is validated in comparison with the actual response: namely, a two-color pyrometer is used to infer the thermal history on the exposed surface around the scanning path, whereas the shape and size of the fusion zone are assessed in the transverse cross-section. With an average error of 3% and 4%, the model is capable of predicting the peak temperature and the depth of the fusion zone upon laser heating, respectively. The model is intended to offer a comprehensive description of phenomena in laser heating in preparation for a further model for repairing via additive manufacturing.

This paper describes the advantages and enhanced accuracy thermography provides to high temperature mechanical testing. This technique is not only used to monitor, but also to control test specimen temperatures where the infra-red technique enables accurate non-invasive control of rapid thermal cycling for non-metallic materials. Isothermal and dynamic waveforms are employed over a 200–800 °C temperature range to pre-oxidised and coated specimens to assess the capability of the technique. This application shows thermography to be accurate to within ±2 °C of thermocouples, a standardised measurement technique. This work demonstrates the superior visibility of test temperatures previously unobtainable by conventional thermocouples or even more modern pyrometers that thermography can deliver. As a result, the speed and accuracy of thermal profiling, thermal gradient measurements and cold/hot spot identification using the technique has increased significantly to the point where temperature can now be controlled by averaging over a specified area. The increased visibility of specimen temperatures has revealed additional unknown effects such as thermocouple shadowing, preferential crack tip heating within an induction coil, and, fundamental response time of individual measurement techniques which are investigated further.

We report the experimental results on a new infrared fiber-optic pyrometer for very localized and high-speed temperature measurements ranging from 170 to 530 °C using low-noise photodetectors and high-gain transimpedance amplifiers with a single gain mode in the whole temperature range. We also report a shutter based on an optical fiber switch which is optically powered to provide a reference signal in an optical fiber pyrometer measuring from 200 to 550 °C. The tests show the potential of remotely powering via optical means a 300 mW power-hungry optical switch at a distance of 100 m, avoiding any electromagnetic interference close to the measuring point.