Effect Of Bending Radius Research Articles

Effect of bending radius on deformation behavior of H62 brass tubes in a less constrained free bending process

Effect of bending radius on deformation behavior of H62 brass tubes in a less constrained free bending process

The Effect Of Drag Link Bending Radius On Fatigue Life And Static Forces Strength

In heavy commercial vehicles, The parts that transfer the movement in the steering box to the wheels are called drag links. Drag links are bent in different geometries due to vehicle designs and other components in the steering system. Drag links are exposed to repeated tension and compression forces on the vehicle depending on the road conditions and the loads on the vehicle. In this study, static buckling forces and fatigue behavior of a drag link were determined according to different bending radii and the effect of bending radius on drag link life was investigated.

Determination of bend angle and shape imperfection effect on collapse load of pipe bends under in-plane opening moment

This study uses a three-dimensional nonlinear finite-element method to investigate the effects of bend angle ([Formula: see text]) and shape imperfection on the collapse load of pipe bends subjected to in-plane opening bending moment using large displacement analysis. ABAQUS was used to create a pipe bend model, whereas by virtue of symmetry about the longitudinal axis, half of the pipe bend model was built. The bend angle was varied from 30° to 180° with an interval of 30°, and shape imperfections, namely ovality ( Co) and thinning ( Ct), were varied from 0% to 20% each at 5% intervals. Elastic-perfectly plastic is thought to be the material of choice for the pipe bend. The results show that the bend angle has a significant impact on the collapse load of pipe bends between 30° and 120°, after which a significant decline was observed. The ovality impact increases with an increase in bend angle for pipe bends with a large thickness, whereas the opposite effect was found for smaller thicknesses with a small bend radius. The effect of bend radius and thickness was significant for large bend angles. Thinning ( Ct) and thickening ( Cth) have no effect on collapse load. A new mathematical equation has been proposed to predict the integrated effect of bend angle and shape imperfection.

Investigations on effect of bending radius on springback behaviour of three-ply clad sheet

Bending operation is widely used in manufacturing of automobiles, aircraft, spacecraft, structures, and home appliances etc. During bending operations, springback is a very common and critical defect. For dimensional accuracy springback must be minimized sufficiently. In the present investigation, the effect of bending radius/punch profile radius on the springback behaviour of SS304/Al1050/SS304 clad sheet has been studied. It has been observed that bending radii /punch profile radii have great impact on the prediction of springback of clad sheet. Springback can be reduced by reducing the bending radius/punch profile radius. The present study confirms that the springback can fairly be controlled by taking optimal value of bending radius/punch profile radius. Sheet placing arrangement of 3-ply clad sheet also affect the springback behaviour minutely. A good agreement has been observed between analytical, numerical, and experimental results of the springback of a 3-ply clad sheet. To evaluate the mechanical properties of three-ply clad sheet, tensile and micro hardness testing have been conducted. The average hardness of 3-ply clad sheet is evaluated as 113.18 HV which may be attributed to the individual hardness of layers of SS304, Al1050 and SS304.

Analysis of the influence of hot rolled plate steel treatment using temper and quench-temper method on vickers hardness number enhancement

This paper wants to know the effect of bending radius on the distribution of hardness, grain distribution and microstructure on the surface area of tensile stress and compressive stress after bending, quenching and tempering. Material testing helps determine and analyze material quality. The research was conducted on the bending of Hot Rolled Plate Steel material with a radius of 50 mm, 55 mm, 60 mm, 65 mm and 70 mm with a measurement distance of 1 mm, 2 mm and 3 mm, the highest value was obtained at a radius of 55 mm with a measurement distance of 1 mm. After getting the quench-temper treatment with a holding time of 30 minutes, the value of 498 HV was obtained at a radius of 70 mm with a measurement distance of 2 mm. Hardness test was performed using the austenite temperature of 900 °С, microstructure test results obtained finer grains in the compression area r=2.173 µm and in the tensile area r=2.34 µm. This observation aims to determine the microstructure of the material undergoing a heat treatment process at a temperature of 900 °С with a holding time of 30 minutes using water cooling media. The results of the observation of the microstructure of the test specimens before the quench-temper process showed that the structure of ferrite was more abundant than perlite, but after the quench-tempering process the results showed that there was more perlite than ferrite due to the presence of austenite. The treatment on the transformation of the Ar3 line causes the hardness to change the shape of the martensite microstructure into steel while the thickness of the carburizing layer increases with the increase in the carbonization temperature on the surface of the quenched specimen, resulting in the formation of martensite and residual austenite causing the coating to become hard.

Effect of bend radius and insulation on adiabatic section on the performance of a single closed loop pulsating heat pipe: experimental study and heat transfer correlation

Pulsating heat pipes are a relatively newer generation of heat pipe which are wickless thus more economical and less fabrication-intensive. These devices are made of a capillary sized tube bent in a serpentine form to result in a closed system. In this study a single closed loop pulsating heat pipe made of 2 mm internal diameter copper tubing is experimentally investigated for two different bend radii. The performance comparison is made for two fluids – methanol and water, for varying heat loads from 10 W to 100 W, with various inclinations from vertical bottom heated mode to horizontal mode, for a constant fill ratio of 60%. The sharper bend, though making the device more compact, is found to reduce the performance. One of the bend geometries is further investigated for the effect of insulation on the adiabatic sections. The insulation is found to certainly widen the heat load range though a distinct performance improvement is not found. The variation of the frequency of pressure pulsations with respect to the fluid, heat load and inclination is also studied. Additionally, one of the geometry is tested with FC 72 fluid as well to arrive at a correlation for heat flux for varying fluids, heat fluxes and inclinations, covering 116 data points. The performance trends predicted by the correlation are in line with those reported in the literature.

Stress simulation of a foldable active matrix organic light‐emitting diode panel with opening thin film transistor structures based on a finite element unit‐cell model

AbstractIn the bending process of a foldable panel, constrained deformation of patterned structures causes local stress concentrations, which results in the damage of internal components or module stacks. In the present work, a unit‐cell finite element method (FEM) model was used to simulate the bending stress in opening thin film transistor (TFT) structures of a foldable active matrix organic light‐emitting diode (AMOLED) panel. Two different opening methods are compared, and the effect of bending radius is further discussed. The simulation results show that the opening structure can slightly decrease the stress around the hole. The influence of the opening on the stress reduction is gradually increased with the decrease of the bending radius. The simulation results provide the basis for optimizing the TFT structure and improving foldable performance of AMOLED devices.

Frequency Response Analysis of Fluid-Structure Interaction Vibration in Aircraft Bending Hydraulic Pipe

For the aviation bending pipe, the fluid-structure interaction 14-equation model is established, and the Laplace transform is used to solve the problem in the frequency domain. For the pipeline with a single elbow, the influence of bending parameters on the frequency response of the pipeline in the frequency domain is analyzed by using the 14-equation. At the same time, for pipelines containing two elbows, we analyze the influence of bending parameters on the natural frequency of the pipeline in different spans. In the end, the accuracy of the simulation is verified by the modal knocking test. Through the above analysis, we reach the following conclusion:the bending angle of the pipeline is greatly influenced by inherent characteristics, the smaller the bending angle, the higher the pipeline’s inherent frequency domain. However, the effect of bending radius will cause the change in length. Usually, the increase of bending radius leads to pipe length increasing, resulting in its inherent frequency decreasing.

Indigenously developed bending strain setup for I-V characterization of superconducting tapes and wires

An indigenously developed bending strain setup to examine the effect of pure bending on critical current of superconducting tapes and strands has been presented in this paper. This set up is capable of applying various bending radius in situ at cryogenic temperature with rack and pinion gear mechanism. The bending strain applied on samples can be controlled externally by rotational input which is transferred in the form of bending radius during experiments. The working principle, design and optimization of this set up have been discussed. The performance and validation of this setup has been done on various HTS tapes and copper strands at 77 K in actual experimental facility. Effect of bending radius (15.5 mm - 48 mm) i.e. strains and ramp rate (2 A/s – 8 A/s) is observed on current capability of various HTS Tapes. It is observed that in uniform bending condition, degradation in current carrying capacity BSCCO and Di-BSCCO (∼ 30 %) is more as compare to YBCO (∼ 2.75 %) at 77 K. The effect of pure mechanical strain has been experimentally observed and presented.

The effect of bending parameters on mechanical properties of bent oak wood

The aim of this study was to investigate the mechanical properties of oak (Quercus petraea Liebl.) wood bent at different radii for locations of the tension and compression sides of wood using micro-mechanical test specimens. Two oak trees having straight stems with approximately 40 cm diameter were selected and two 4 m long logs were cut. Two different steaming pressures, two setting methods, and three different bending radii were examined. Additionally, a set of three controls was unbent. Mechanical properties including the modulus of rupture, modulus of elasticity in bending, tension and compression strength parallel to grain were measured from the convex and concave sides of all samples. Bending strength, modulus of elasticity in bending, tension strength and compression strength properties on convex sides were greater than the corresponding properties on concave sides. All strength values significantly decreased with decreasing bending radius on both sides. On the convex side, strength and stiffness values of oak wood at 300 mm radius were greater when compared to control groups while the strength and stiffness values of oak wood were lower for 100 mm radius. The values for 200 mm radius, on the other hand, were not significantly different compared to the control group value. On the concave side, all of the bent groups had significantly lower strength and stiffness values than that of control group. The effect of bending radius and setting method on the strength and stiffness values of oak wood was statistically significant on both concave and convex sides. The effect of steam pressure was not significant.

Effect of Bend Radius on Magnitude and Location of Erosion in S-Bend

Solid particle erosion is a mechanical process that removes material by the impact of solid particles entrained in the flow. Erosion is a leading cause of failure of oil and gas pipelines and fittings in fluid handling industries. Different approaches have been used to control or minimize damage caused by erosion in particulated gas-solid or liquid-solid flows. S-bend geometry is widely used in different fluid handling equipment that may be susceptible to erosion damage. The results of a computational fluid dynamic (CFD) simulation of diluted gas-solid and liquid-solid flows in an S-bend are presented in this paper. In addition to particle impact velocity, the bend radius may have significant influence on the magnitude and the location of erosion. CFD analysis was performed at three different air velocities (15.24 m/s–45.72 m/s) and three different water velocities (0.1 m/s–10 m/s) with entrained solid particles. The particle sizes used in the analysis range between 50 and 300 microns. Maximum erosion was observed in water with 10 m/s, 250-micron particle size, and a ratio of 3.5. The location of maximum erosion was observed in water with 10 m/s, 300-micron particle size, and a ratio of 3.5. Comparison of CFD results with available literature data showed reasonable and good agreement.

A novel bend-resistant large-mode-area photonic crystal fiber

A novel bend-resistant large-mode-area silica photonic crystal fiber (PCF) is proposed and fabricated. With the advantage of flexible design on the PCF configuration, the properties of large-mode-area, single mode propagation and low bend loss can be simultaneously achieved by intentionally designing the position of defect and the size of air holes. Modal properties and bending loss of the actual PCF can be evaluated with previous model for assessing the properties of the actual fiber. Numerical results demonstrate that this fiber has an extremely large mode area of 2812 μm2, low confine loss of 0.00024 dB/m of the fundamental mode and high confine loss of over 1.248 dB/m of higher order mode at a wavelength of 1064 nm when the optical fibre is kept straight. The large difference in propagation loss levels between fundamental mode and higher order modes ensures the efficient single-mode propagation in the fiber core. Furthermore, the effects of bend radius and bend direction angle on bend loss are investigated when the fiber is bent. Even if bend radius is as small as 5 cm, bend loss of this fiber is still below 10-3 dB/m. It is found that the proposed fiber has the negligible bending loss at a bending radius of 30 cm with the bending angle ranging from -60° to 60°. These results illustrate that the fabricated fiber possesses the better bend resistant properties and can overcome the sensitivity to bend direction angle caused by the asymmetric structure. The fabricated fiber will play an important role in developing high power fiber laser, fiber amplifier and high power delivery application.

Numerical and experimental study on rotary draw bending of aluminium alloy tubes

Abstract In this paper a 3D finite element model of the bending process for circular aluminium alloy tube has been built using the explicit code eta/Dynaform and validated by comparing the experiments. The experiments were carried out by using a hand bender with the same bending principle as a rotary draw numerical controlled (NC) bender. The relationship between quality parameters of bent tubes, in terms of cross-section distortion and wall thinning, and the angular position along the bent tube is discussed experimentally in combination with FE simulation. Then, the effects of bending radius (R) are investigated using simulation of the bending process based on the finite element model. The results show that with the increase of bending radius, the cross-section degradation factor (Ψ) and wall thinning degree (ξ) decreases rapidly.

Effects of bending on heat transfer performance of axial micro-grooved heat pipe

Heat pipe is always bent in the typical application of electronic heat dissipation at high heat flux, which greatly affects its heat transfer performance. The capillary limit of heat transport in the bent micro-grooved heat pipes was analyzed in the vapor pressure drop, the liquid pressure drop and the interaction of the vapor with wick fluid. The bent heat pipes were fabricated and tested from the bending angle, the bending position and the bending radius. The results show that temperature difference and thermal resistance increase while the heat transfer capacity of the heat pipe decreases, with the increase of the bending angles and the bending position closer to the vapor section. However, the effects of bending radius can be ignored. The result agrees well with the predicted equations.

Investigation of bending loss in a single-mode optical fibre

Loss of optical power in a single-mode optical fibre due to bending has been investigated for a wavelength of 1550 nm. In this experiment, the effects of bending radius (4–15 mm, with steps of 1 mm), and wrapping turns (up to 40 turns) on loss have been studied. Twisting the optical fibre and its influence on power loss also have been investigated.

The effect of bending radius on V-I characteristics of mono- and multicored BiPb-2223 tapes with and without Ag additions

The effect of bending strain on Voltage-Current Characteristics (VCC) of BiPbSrCaCuO-2223/(Ag and Ag-alloy sheathed) tapes with and without Ag additions into the core have been studied. The testing probe allows us to carry out all set of bending tests up to radius 5 mm on the same specimen. The critical current Ic and shape of high-sensitivity VCC as a function of bending strain are analysed. Degradation of current carrying capacity under bending deformation is caused by the formation of microcracks. The overlapping of microcracks in Bi-2223/Ag sheathed tapes without Ag additions leads to current overflow into the Ag sheath and to appearance of linear resistance segment in the V-I curve at low electric field.

Helical gas—solids flow II. Effect of bend radius and solids flow rate on transition velocity

The transition velocity is defined here as the gas velocity at which minimum pressure drop occurs during pneumatic transport of coal char particles. As expected, these transition velocities decreased with larger bend radius and increased with solids flow rate. The velocities were also higher than those predicted from the Rizk correlation for transition velocities in horizontal tubes. Believing that centrifugal forces contribute to these higher transition velocities in helical coils, we modified the Rizk correlation to account for these centrifugal forces. Predictions from the modified correlation agree closely with experimental results.