Needle Temperature Research Articles

Study on the wear characteristics of cylindrical needle bearings on the crankshaft of RV decelerator

PurposeThe purpose of this study is to systematically analyze the wear of cylindrical needle bearings in rotary vector reducers under temperature rise and identify the influencing factors.Design/methodology/approachBased on the dynamic characteristics of the RV-20E reducer, the time-varying contact force of the cylindrical needle bearing and the entrainment speed of the inner and outer raceways were calculated. A mixed elastohydrodynamic lubrication model of the needle bearing, considering friction and temperature rise, was established using a dynamic rough tooth surface model. The model solved for the oil film thickness, contact stress and wear conditions of the bearing raceway contact area. The effects of the number of rolling needles, the diameter of rolling needles and surface strength on the wear characteristics were analyzed.FindingsThe results of this study show that the oil film thickness, oil film pressure and surface scratches of cylindrical needle bearings exhibit an uneven, patchy distribution under the combined effects of friction and temperature rise. When the radius of the rolling needle is less than 1.44 mm, inner ring wear is less than outer ring wear. Conversely, when the radius exceeds 1.44 mm, inner ring wear is greater. The optimal rolling needle radius is 1.6 mm. Increasing the number of rolling needles and enhancing the yield strength of the contact surface significantly extend bearing life.Originality/valueThis study provides valuable recommendations for optimizing bearing structural parameters and material characteristics in the design of rotary vector reducers.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2024-0242/

Study on preparation and properties of silver alloy for Mongolian medicine acupuncture

The Mongolian medical silver needles often encounter issues of bending, fracturing, and blunting in clinical applications. Similarly, Mongolian warm needles can cause burns on patients due to inaccurate temperature control. In this study, we developed an Ag85Cu15 alloy specifically for acupuncture needles based on material preparation. By incorporating appropriate amounts of Mn and Ti elements, we were able to enhance the mechanical properties and biocompatibility of the acupuncture needles. Compared to commercially available silver needles, this alloy exhibited a significant increase in microhardness up to 210.2 Hv0.2 and an improved tensile strength of 880.2 MPa. Furthermore, we designed a thermoelectric effect-based temperature measurement model for precise control of the warm needle's temperature, enhancing the therapeutic effectiveness of the treatment.

Analysing The Effects of Knitted Fabrics Physical Properties to The Heating of Sewing Machine Needles

Due to the increasing demand in the clothing industry, industrial sewing machines operate at high speeds ranging from 2000 to 3000 revolutions per minute. One of the most significant problems that adversely affect the stitching quality and efficiency is the needle temperature, which reaches up to 300 oC and is influenced by various parameters such as machine speed, thread tension, and fabric properties. In this study, the heat generated from the friction between the needle and the textile surface in knitted fabrics and the fabric properties affecting heat are examined. Four different knitting techniques and twelve different knitted fabrics with varying weights, thicknesses, and blend properties were used. An Optris CT3M pyrometer was employed to measure the temperature on the needle. The results can be summarized as follows: in all knitted fabrics, an increase in fabric weight and thickness was observed to correspond to an increase in needle temperature values. The highest needle temperature values above 90 oC were obtained in TF2-coded three-thread fleece fabric with a fabric thickness of 1.31 mm and a fabric weight of 340 g/m2, while the lowest needle temperatures of 66 oC and below were achieved in the lightest and thinnest fabric with a fabric weight of 100 g/m2 and a thickness of 0.39 mm. Additionally, no significant relationship was found between fabric stitching density and needle temperature.

Investigation of Factors Influencing Rise in Needle Temperature to Enhance the Production and Seam Performance –part I

ABSTRACT The most recent industrial sewing machines are designed and developed to give high production and quality. These machines are capable to operate at very high speed. On the other hand, the sewing machines operated at high speed are facing the challenge of very high needle temperature generation which leads to seam damages like burnt holes, stiff seam, molten seam etc. Such seam damages are serious issue and affects the performance of the garment produced. An attempt was taken to analyze the factors influencing the rise in needle temperature change during sewing to derive exact solution to the problem. Thermal camera was set up in the sewing machine and change in needle temperature under varying influencing parameter was recorded and taken for analysis. From this study, it is found that twill fabric and interlock fabric with superimposed seam of four layers and high needle tension produced higher needle temperature. The other factors such as sewing thread, stitch density, needle size etc falls in next level of contribution.

Investigation of Change in Sewing Needle Temperature: Part I: Influence of Fabric Types and Sewing Parameters

Abstract In modern industrial sewing, the further rise in sewing speed to increase production is mainly influenced by the extent of needle heat generated. The increased needle heat leads to damage to the sewing thread and fabric and a loss in productivity. Hence, the change in sewing needle temperature under various fabric types and sewing conditions is investigated for better understanding. An objective method to assess the generation of needle heat by utilizing a thermal camera is attempted, and the effects of change in needle heat by varying the parameters are assessed. The results from the thermal camera are statistically analyzed. The superimposed seam with a greater number of layers and high needle tension produced high needle heat, whereas poly-poly core spun sewing thread, 100 % polyester fabric, and a high stitch density contribute to the next level of needle heat generation. This investigation considered all the possible influencing parameters objectively and helps in maintaining reduced needle heat for a chosen fabric type and sewing conditions to improve the productivity with increased sewing speed.

Liver tumor ablation enhancement by induction-heating system with bitter-like deep magnetic field coil.

The heated metal needle used for tumor thermotherapy is considered crucial for enhancing the practicality of cauterization using electromagnetic induction-heating techniques. In this study, a novel coil capable of producing a deep magnetic field is designed. In the proposed design, the coil structure is improved to enhance the intensity of the coil's deep magnetic field and its suitability for deep-tissue cauterization. Furthermore, a series of experiments are conducted using a single and consistent input current. The heating experiments are conducted at varying depths by placing the needle beneath the coil. The proposed coil significantly increases the induction-heating temperature and provides a solution to the long-standing problem of insufficient needle temperature. This research has also improved the usability of the induction-heating equipment in the field of deep tumor ablation.

Evolution and comprehensive evaluation of viscoelastic characteristics of road asphalt in medium temperature region

PurposeIn order to determine the range of medium temperature zone of road asphalt, it is hoped that the evolution of viscoelastic characteristics of road asphalt under medium temperature state can be deeply explored.Design/methodology/approachIn this paper, the needle penetration test and temperature scanning test were designed for 90# and 70# bitumen as test materials, and the boundary of medium temperature zone of 90# and 70# bitumen was accurately determined by data analysis method. A mathematical model was established based on principal component analysis, and a comprehensive evaluation index was proposed to evaluate the evolution of temperature viscoelastic characteristics of road asphalt by means of standardization and rotational dimensionality reduction.FindingsThe test results show that the medium temperature zone of 90# asphalt is [−5 ± 1°C, 38 ± 1°C], and the medium temperature zone of 70# asphalt is [0 ± 1°C, 51 ± 1°C]. According to the viscoelastic response of road asphalt in the medium temperature zone, the medium temperature zone can be divided into three evolution stages: weak viscoelastic stage, viscoelastic equilibrium stage, strong viscoelastic weak stage. Analysis based on the intrinsic viscosity fillip target describing the various intrinsic viscoelastic index represents the viscoelastic properties of bitumen from different angles, and limitations inherent stick fillip for target put forward the integrated the inherent stick fillip mark information, as well as targeted and accurate evaluation of road asphalt temperature comprehensive evaluation indexes in the evolution of the viscoelastic properties of IM-T. Finally, the temperature data of asphalt pavement in several representative regions of China are compared with the determined medium temperature region, and it is proved that the research on the evolution of viscoelastic characteristics of asphalt pavement under the medium temperature condition has important practical significance.Originality/valueThe boundary of medium temperature zone of 90# and 70# base asphalt was determined, and the viscoelastic characteristic evolution of road asphalt under medium temperature state was studied deeply. Aiming at the limitation of intrinsic viscoelastic index, a comprehensive evaluation index IM-T which not only integrates the information of intrinsic viscoelastic index but also can accurately evaluate the evolution of temperature viscoelastic characteristics in road asphalt is proposed.

Coexistent Heteroblastic Needles of Adult Pinus canariensis C.Sm. ex DC. in Buch Trees Differ Structurally and Physiologically

Great variation in shape and size between primary (juvenile) and secondary (adult) needles, so-called leaf-heteroblasty, occurs in several Pinus species. Most of them loss primary needles during the juvenile-to-adult transition of the tree. An exception to this is Pinus canariensis (a Canary Islands endemism) in which basal resprouting twigs of adult trees frequently wear both primary and secondary needles. Taking advantage of this extraordinary study-case-species, we conducted an exhaustive comparison of both needle types through quantitative analyses of needle anatomy, photochemical performance, gas exchange, and resistance to extreme dehydration and to extreme needle temperature. We hypothesized that primary needles would show lower investment to leaf structure but higher photosynthetical efficiency. Primary needles had less stomatal density and thicker and less wettable cuticles. In cross section, primary needles showed smaller structural fraction (e.g., percent of hypodermis, endodermis and vascular tissue) and higher fraction of photosynthetic parenchyma. Significant differences between primary and secondary needles were not found in net carbon assimilation not in their leaf mass area values. Interestingly, secondary needles showed higher electron transport rate, and they were additionally much more efficient in retaining water under severe and controlled desiccant conditions. When subjected to extreme temperatures (−10° to +50 °C), primary needles recovered better their photochemical efficiency than secondary needles, after +46° and +48 °C heat-shock treatments. Our results indicate that both needle types broaden the diversity of physiological responses against environmental constrains in basal twigs of adult P. canariensis trees. Considering that this is a fire-resistant and resprouting species, this advantage could be particularly useful after a drastic environmental change such a fire or a gap opening in the forest.

Measurement of Industrial Sewing Needle Temperature with Different Experimental Techniques

Measurement of Industrial Sewing Needle Temperature with Different Experimental Techniques

Effects of Flexible Induction Coil Pitch on the Heating Performance of Thermotherapy Needles

This article presents a newly developed flexible laminated copper (FLC) coil for electromagnetic thermotherapy that has several advantages over traditional hard copper coils. We study the effect of pitch (the distance between coil turns) on the heating performance of the proposed FLC coil. The flexible coil can be wound into different shapes for various purposes. However, the output power of the heating system can be substantiality affected by the coil inductance. This study is aimed at reducing coil inductance by changing the original flexible coil diameter and pitch in order to enhance the output power of a high-frequency machine, improve treatment, and meet the actual heating requirements. The results of the experiments show that the temperature is six times better when using the flexible coil compared with when using the traditional hard copper coil, where adjusting the coil pitch can increase the needle temperature by a maximum of 48.3 °C in pork liver tissue. In addition, this study simulates the distribution of the magnetic field of the flexible coil via a finite element analysis and explores the coil design and heating effect of metal needle heating and liver tissue ablation. The improved features of this proposed method are threefold: 1) the flexible coil can be used to treat different zones of the human body; 2) the flexible coil exhibits better heating performance than a hard copper coil; and 3) the coil inductance is lowered, and the power is improved, which, in turn, leads to better treatment and meets the actual heating requirements.

Optimization of a green solid-state fan for electronics cooling applications

Miniaturization and high integration are two important factors hindering the further development of electronic devices. The generated heat flux has been increasing, thus requiring efficient cooling systems. The corona wind cooling technology has significant advantages and is likely a new effective solution for cooling electronics. A high-performance solid-state fan (SSF) based on corona discharge was designed and optimized. Carbon nanotubes and catalysts are used to modify the SSF in order to reduce ozone generation and cool a high power light-emitting diode (LED) chip. The experimental results indicate that the needle electrode arrangement, discharge polarity, temperature and relative humidity have a significant effect on the performance of the SSF. The positive corona, high environmental temperature and low relative humidity are beneficial to the original SSF. The modified SSF decreased the initiation voltage by half, increased the velocity by 13%, and reduced ozone production by more than 90%. The greener SSF showed better working durability and cooling performance, which reduced the case temperature by another 6 ℃ compared to the original one.

A Temperature-Controlled Laser Hot Needle With Grating Sensor for Liver Tissue Tract Ablation

In this article, we proposed a laser hot needle for liver tissue tract ablation. The proposed laser hot needle is powered by a 4500-nm-diode laser incorporated with a closed-loop control system that comprises of a uniform fiber Bragg grating (FBG) temperature sensor and a computer. Based on the real-time feedback input from the FBG temperature sensor, the laser power is regulated by a proportional–integral–derivative (PID) control system to control the needle temperature. In the characterization test, a chirped grating-based distributed temperature sensor is employed for measuring the tissue temperature profile in the ex vivo bovine liver tissue during the ablation. A histological test is conducted to study the impact of tract ablation to the cellular structures of treated tissue and tissue coagulation. In a tract ablation test, a ~50-mm $\times \sim 6$ -mm (length $\times $ width) thermal denaturation zone has been created on ex vivo bovine liver tissue with the laser hot needle at 150 °C.

Effect on bubble dynamics during pool boiling heat transfer in a novel aqueous binary mixture of surfactants

Temperature near the heating region changes with the water boiling curve when the heat flux applied. In this study, experiments were carried out by maintaining a cylindrical subcutaneous hypodermic needle as a single active nucleation site. By controlling heat supplied to the site, a single bubble was formed in the saturated water. The boiling phenomenon was recorded. The surfactants used were sodium dodecyl sulfate (SDS) and centrimonium bromide (CTAB). Aqueous binary mixture SDS-CTAB was prepared on a volume percent basis. The effect was measured by studying a single bubble. The vapor bubble resulting from the nucleation site was observed. Bubble parameters, without and with a surfactant, were plotted in two heat fluxes concerning the excess temperature. It is found that, compared with saturated water, the average measurements of bubble detachment diameters and terminal velocities decreased, but the bubble departure frequency increased. On the other side of analysis, with increasing excess needle temperature of site, at 601 kW/m2, the detachment diameter decreased, departure frequency increased, rising velocity was increased and at 950 kW/m2, the detachment diameter increased, departure frequency increased, rising velocity decreased.

Needle temperature and pain perception in the treatment of rheumatic heart disease

Aim: Patients with rheumatic heart disease (RHD) are committed to lifelong secondary prophylaxis with antibiotics. The study was conducted to evaluate the effect of cold needle to decrease the pain associated with this injection. Material and methods: A randomised crossover single-blinded study was conducted among 100 patients receiving penicillin with room-temperature needle and cold needle (0–2oC) in random order. Pain was evaluated using numerical pain rating scale and bio-physiological measures. Results: There was a significant decrease in subjective pain score when cold needle was used as compared to room-temperature needle (3.37 ±1.75 vs 5.58 ±1.68, P≤0.0001). Conclusion: Cold needle decreased pain perception of patients receiving intramuscular injection of benzathine penicillin. Pain-reducing technique may be useful in improving compliance of patients receiving benzathine penicillin.

Low melting point metal-based flexible 3D biomedical microelectrode array by phase transition method

In this study, we present a dimension-controllable 3D biomedical microelectrode based on low melting point metals (Bi/In/Sn/Zn alloy) applied using the phase transition method. We have established a process, in which the liquid metal is pumped through a syringe needle of the dispensing system to form a needle shape after cooling at room temperature. PDMS (polydimethylsiloxane) was chosen as the substrate of the electrode as it is amenable to micro-molding and has excellent flexibility. Several key factors, including lifting velocity of the syringe needle and sample temperature were examined as to how they would affect the height, width and depth-width ratio of the electrode, to realize size control of the electrode. Afterwards, the skin-electrode impedance was tested and the results were compared with those of an Ag/AgCl (wet) electrode. The impedance at 10 Hz is 2.357 ± 0.198 MΩ for the 3D microelectrode. From data, the impedance of 3D microelectrode is found to be at the same level as the Ag/AgCl electrode at the frequency of 10 Hz. By increasing the size of the array, the impedance of the low melting point metal electrode and the wet electrode converge. The resistance of the electrode was also measured to describe its stretchability. The electrode can be stretched to a maximum of 42% before it becomes non-conducting. In addition to acquisition of bio-electric signals, our method has strong prospects in the field of bio-sensing.

Electrical Tree in HTV Silicone Rubber With Temperature Gradient Under Repetitive Pulse Voltage

High temperature vulcanized silicone rubber (HTV SIR) is important insulation for high voltage direct current (HVDC) cable accessories. The pulse voltage in the HVDC system may initiate an electrical tree in SIR insulation. During the operation, there is a temperature gradient in SIR caused by the different temperatures of conductor and external environment. So it is necessary to research the electrical tree initiated by pulse voltage under the temperature gradient. In this paper, electrical trees in SIR with different temperature gradients were recorded. The inception voltage, tree length, and accumulated damage (AD) distribution were analyzed. The experiment results indicate that tree inception voltage decreases with the increase of temperature of the ground electrode when the needle temperature is 90 °C, it also decreases with the increase of needle temperature when the ground temperature is 90 °C. All the trees are in bush structure when the ground temperature is 90 °C, the structure changes from branch to bush with the increase of ground temperature when the needle temperature is 90 °C. When the needle temperature is 90 °C, AD distribution changes obviously with the increase of ground temperature. The conductivity of SIR under different temperatures and electric fields was tested. The effect of changing conductivity on tree inception was discussed. Surface potential decay (SPD) at different temperatures was tested. The trap characteristics and charge kinetic properties influenced by temperature may be the main reasons for the change of tree structures in the growth process.

Influence of Stitching Parameters on the Joint Strength of Welded-Stitched Composites

Abstract Regarding the necessity of lightweight construction, performance and design, composites are well established. At this moment, the joining of these composites still is often a major challenge. While suitable technologies like welding, sticking or riveting do exist, there are several drawbacks of these technologies such as damaging the fiber structure and low bonding strength. The combination of welding and sewing is a novel approach to improve the bonding of glass fibre-reinforced polypropylene and the influence of the processing parameters is not yet well understood. This study aims at analyzing the influence of parameters such as operating temperature, overlap length, needle temperature and thread material on the tensile strength of thermoplastic composites joined in the previously described hybrid approach. Furthermore, the interaction between thread and composite material is investigated by a microscopical analysis. The joint strength has been found to depend on the overlap length of the joint and the results suggest a contribution of the seam to the joint strength, especially for lower overlap lengths. Influences of the processing temperature, the thread material and needle temperature are also present, however, due to the complex interaction, no systematic conclusions could be drawn for these yet. The optical analysis confirms the findings of thermoset composites stitched before impregnation, where additional seams cause dislocations and local agglomeration of fibers. Additional investigations are necessary to determine the effect of the stitching on the joint and to further the understanding of the interaction between composite and thread material.

Quantification of injection force mechanics during injection laryngoplasty.

In-office or operative injection laryngoplasty requires needle stability for accurate material placement. To date, no reports compare injection forces based on needle gauge, bends, length, or material type or temperature. We hypothesize these factors alter injection forces and could impact clinical use. Swine larynges were placed in a compression testing machine. Syringes were affixed to a stabilizing crossbeam. Straight needles (25G 1.5-inch; 27G 1.25-inch; or 9.8-inch malleable shaft 16G per oral with 24G tapered needle tip) were inserted into the swine vocal folds to simulate realistic tissue resistance pressure. Compressive loading was conducted at 40 mm/minute until steady-state force was achieved. Tests were completed with calcium hydroxylapatite (CaHa), carboxymethylcellulose, and hyaluronic acid at various temperatures and CaHa with various bends in the needles (n = 3 per group, comparisons performed by two-way analysis of variance (ANOVA), Tukey's post-hoc). Needle size, shape, and temperature altered injection force. Steady-state force was highest with the per-oral needle at a mean of 44.55N compared to 26.44N and 29.77N in the 25G and 27G percutaneous needles, respectively (P < 0.001). Stiffness rate (initial increasing force vs. distance to initiate injection) ranged from 19.75N/mm (per oral) to 22.06N/mm (25G) to 24.56N/mm (27G), (P = 0.875). Adding multiple bends to the per-oral needle increased stiffness rate to 24.99N/mm (P = 0.035), whereas the 25G needle stiffness rate remained unchanged (P = 0.941), with the stiffness rate decreasing in the 27G needle with increasing bends (P = 0.033). Increased temperature decreased injection forces across all materials. Needle caliber, length, and bends impact steady-state forces and stiffness rates during vocal fold injection. NA Laryngoscope, 129:1060-1066, 2019.

DC electrical tree initiation in silicone rubber under temperature gradient

In this paper, initiation behaviors of DC electrical tree in silicone rubber were studied under different voltage polarities and temperature gradients (temperature of needle and ground electrodes ranged from 20 to 120 °C). Electrical tree initiation probability, tree shape, and tree length were obtained via the statistics. The results show that polarity effects, where the positive DC voltage is easier for trees to initiate, appear evidently under various temperature situations. As for the temperature gradient, tree initiation voltage decreases first and then returns to a larger value with the increasing needle temperature when the ground electrode temperature is fixed at 20 °C. Both the probability of multiple-branch tree and corresponding tree length increase and subsequently decrease. However, tree initiation voltage decreases alone and tree length increases with the rise of ground electrode temperature when the needle temperature is fixed at 20 °C. Homo charge injection becomes easier with increasing needle temperature following the Schottky-Richardson approximation under ramped DC voltages. In addition, electric field strength at the tip decreases when the needle temperature is higher than ground temperature, since the conductivity is sensitive to the local temperature and electric field. It is believed that the needle temperature and the temperature gradient dominate tree initiation behaviors, where the former affects the collisional ionization and partial relaxation of silicone rubber chains, and the latter decides electric field distribution in the bulk.

Development of Temperature-Controllable Acupuncture System using High-Frequency Electromagnetic Field

We developed a temperature-controllable acupuncture (TCA) system incorporating a high-frequency electromagnetic field to reduce the burn risk posed by traditional acupuncture combined with moxibustion method. Our technique can control the acupuncture needle temperature safely and appropriately. We designed a solenoid-type electrode and a 150-kHz high-frequency electromagnetic generator. Regarding the system performance, we found that the time required to reach 42 °C is only 52 seconds compared with traditional acupuncture combined moxibustion method which takes 150–270 seconds. In addition, we conducted a pilot study involving 20 participants to examine the possibility of clinical application. We performed manual acupuncture and TCA on the LI9, LI10, and TE5 acupoints, and only the acupunctures of TCA group were heated using the developed system at 38–40 °C. In addition, we measured the hand-temperature and blood-flow velocity before and after stimulation to determine their variability. The hand temperatures increased after stimulation in both groups, but only the TCA group exhibited a significant difference (p=0.001). The blood-flow velocities of the two groups exhibited different patterns. The blood-flow velocity was increased by 6.3 % for the TCA group (p=0.114), but decreased by -12.78 % for the manual acupuncture group (p=0.011). We found that this new method is not only safe and convenient, but also precise and effective. Moreover, an electromagnetic field has various therapeutic effects and, thus, may induce its own positive benefits.