Steel Hub Research Articles

Analytical models for predicting the moment‒rotation relationships of steel hub joints with bolted steel side plates in single-layer wood reticulated domes

A very popular and efficient pattern of joints adopted for wood reticulated domes is steel hub joints featuring end-bearing and bolt-connected wood members (EBBC joints). This type of joint shows clear semi-rigidity, which affects the rigidity and overall stability of the structures. This study developed analytical models for predicting the moment‒rotation curves of EBBC joints, considering the effect of axial compression. Specifically, two models termed the WR and WEP models, were developed assuming rigid and elastic-plastic constitutive behaviour, respectively, of the wood in the compression zone of the joint. A tri-linear model for the lateral force-slip relationship of bolt connections was derived. A formula for calculating the deformation modulus and predicting the shear failure of wood members under local compression was proposed and verified. The moment–rotation relationship of the joint was established with equilibrium and compatibility conditions. The accuracy of the analytical models was verified by comparison with a series of experimental results as well as the parametric study results obtained using a refined finite element model. It was revealed that both the WR and the WEP models can predict the moment–rotation relationships accurately for joints without axial compression, whereas for the case of non-negligible axial compression loads, the WEP model offers more accurate predictions. The analytical WEP model proposed in the current paper provides a versatile tool for general design practice to predict moment–rotation curves for traditional or novel EBBC joints.

Study on the rotational performance of steel hub joints of wood reticulated domes subjected to monotonic bending moment

Study on the rotational performance of steel hub joints of wood reticulated domes subjected to monotonic bending moment

Quasistatic strain fields in normally- and tangentially-loaded elastomeric rollers under impending slip

Elastomeric rollers are important components in applications such as printing and roll-to-roll manufacturing. To gain insight into roller mechanics and provide a basis for further investigations into dynamic rolling problems where rolling instabilities may arise, we employ a specially-designed apparatus to obtain displacement and strain fields via digital image correlation (DIC) under applied loads. We test loading scenarios leading to impending slip of an elastomeric roller, mounted on a steel hub, and in contact with a glass (rigid) substrate. We first examine strain fields under normal loading and compare them with the closest analytical predictions. We then progress to analyzing the strain fields under combined normal and tangential loading. For each loading scenario, we discuss the displacement and strain fields of the roller sidewall and contact interface. We use a conceptual string model to explore how stick and slip zones develop within the contact area as well as how memory effects arise during cyclic loading. This memory effect is then verified experimentally using the DIC strain fields. Additionally, we demonstrate a means for identifying the stick zone area between the roller and substrate using the experimentally-obtained displacement fields. We believe the apparatus, and the ability to obtain experimental displacement and strain fields, will prove valuable in understanding roller mechanics and associated instabilities.

The Study of the Performance of the Diamond Wheel’s Steel and CFRP Hubs in Tungsten Carbide (WC) Grinding

Tungsten carbide (WC) has been widely utilized in recent years in the hardware, mechanical, and chemical industries and in national defense because of its high hardness, anti-wear, low temperature, and anti-corrosion properties. However, using it for grinding is also challenging because the WC material has high hardness and brittle characteristics. The typical hub of a diamond wheel is made of steel. In high-speed grinding, the steel hub of the diamond wheel is subjected to gravity and centrifugal forces, which cause grinding wheel vibration, poor workpiece processing quality, and a short machine life. Therefore, this study used a carbon-fiber-reinforced thermoplastic (CFRP) hub to replace the steel hub when grinding the WC workpiece. It aimed to investigate methods to reduce oscillation, improve chip efficiency, and increase accuracy in the WC workpiece. The research results demonstrated that using a CFRP hub in the grinding wheel can reduce the oscillation when the peripheral speed of the grinding wheel is at 20–100 m/s. Additionally, the surface roughness average (Ra) of the workpiece can be reduced to 3.2–25.4% and the ten-point height of irregularities (Rz) can be reduced to 18.9–44% compared to using a steel hub in the grinding wheel.

LCA-based Multi-scenario Study on Steel or Aluminum Wheel Hub for Passenger Vehicles

Lightweighting is one of the enabling techniques for energy saving and carbon reduction in the automotive industry. However, the life cycle performance of lightweight components remains unclear. Wheel hub is an important component, and its trend of replacing steel with aluminum is happening. Based on life cycle assessment and using ReCiPe model, this paper reports a cradle-to-grave study on the environmental impact of steel and aluminum wheel hub in passenger vehicles. Considering multi-scenario in the Chinese market, it is found that when the service life of passenger vehicle is less than 5.6 years, steel wheel hub is more environmental-friendly, and when the service life is less than 8.6 years, steel wheel hub also has more economic advantages. Combining different lightweight methods and different types of vehicles, it is found that structural optimization reduces the environmental impact of per unit weight mostly, process optimization reduces the life cycle environmental impact of wheel hub, and using lightweight steel wheel hub in electric vehicles has more potential in environmental benefits. some suggestions are, 1) to choose wheel hub that matches your actual usage to enjoy more environmental-economic advantages; 2) to prioritize structural-process integrated optimization for lightweight wheel hub; and 3) to use more lightweight components in electric vehicles.

Resource Management and Utilization of Lean Grade Iron Ore Resources of Karnataka, India

As per the National Steel Policy 2017, more than 300 million tons of steel needs to be produced by 2030, to meet the increased demand due to the tripling of per capita consumption of steel in India. Accordingly, the local steel production from the Ballari steel hub of Sandur schist belt is expected to be raised from present 25 million tons per year to 60 million tons per year by 2030, thus necessitating 150 million tons of high grade hard lumpy/pellets for domestic Ballari steel hub alone excluding long term export commitments. Hence, a strategy for processing lean grade iron ores to augment the demand of high-grade iron ores for metallurgical applications is studied. A composite mixed Banded Hematite Quartzite (BHQ) from different ranges of Sandur schist belt, Ballari district, Karnataka, India was subjected to characterization, mineral processing and palletization studies to produce pellets Fe > 62.5 %, (SiO2+ Al2O3)2, 1.00 % Al2O3and 1.06 % LOI, comprising fine grained (<70 ?) mainly hematite [55–60%], very fine grained (<40 ?) quartz [35- 40%] and fine grained (<70 ?) minor amounts of martitized magnetite [1–5%], which are mutually intimately intermixed and intergrown, was subjected to beneficiation. The BHQ is amenable to gravity concentration by tabling reverse flotation, and WHIMS produces pellet grade concentrates. The final conventional process comprising gravity concentration, followed by magnetic separation of gravity tails and refining of magnetic fractions by reverse flotation. The final concentrate has produced assaying 64.5% Fe, 6.32% SiO2, 0.29% Al2O3 and 0.63% LOI, with 73% Fe distribution, has met the pellet grade specification. The pellets produced from beneficiated iron ore concentrate is assayed 64.10 % Fe, 6.85 % SiO2, 0.42 Al2O3%. DRI could be produced from the pellets from which steel is produced paving the way for conservation, sustenance, and sustainable development with the viability of using BHQ of the Sandur schist belt.

CSR and Corporate India: A Study on Public and Private Sector Divide

Abstract: CSR is increasingly a misunderstood and much debated concept worldwide. There is a saying in the business, “Business of the business is to do business and nothing else”. Profit is the only and dominating objective of the business, as profit is needed both for the working and growth of the business. Over the time, there has been a sea change in the objectivity and priority of business. From a commercial unit, the business now has been a social entity with corporate citizenship. CSR is fast becoming an increasing business strategy both nationally and globally. CSR practices of Indian companies got a radical boost with statutory provision in the Companies Act 2013 that make it mandatory to every Indian company and foreign entity with Indian presence to spend 2 per cent of its average net profits of its profit made during the three immediately preceding financial years, in pursuance of its Corporate Social Responsibility Policy. There exists difference in the outlook of companies towards social causes and varying CSR policies and practices. Also Public and private sector divide in CSR practices prevails. There is need for continuous investigation of the changing social and economic needs and the role of corporate houses in meeting the aspirations of the stakeholders and the society at large. Keeping this in view, the present paper entitled “CSR and Corporate India: A Study on Public and Private Sector Divide” is a sincere attempt to make a comparative analysis of CSR practices of public sector and private sector companies with special emphasis on industries of Kalinganagar steel hub of Odisha. Keywords: CSR, FDI, MoUs, Corporate India.

Influence of the interference level and of the assembly process on the shear strength of loctite 648 anaerobic adhesive

ABSTRACTThe aim of this research is to study the effect of the interference level and of the coupling procedure on the shear strength of Loctite 648 anaerobic adhesive. The tests involved shaft-hub joints with a quite large interference range and joined by a broad range of coupling strategies, which is one of the main issues of novelty of this research. 42CrMo4 tempered steel shaft specimens and 16CrNi4Pb hardening steel hub samples were used. Two factors were considered: the interference level and the assembly strategy. Four different levels of specific interference were analyzed up to a maximum value of 0.22%, performing five replications per level. Experimental trials were carried out with different coupling procedures: using press-fitted and shrink-fitted joints. Using the first procedure, a high level of interference induces scratches on the sample surfaces. These are conversely not produced by shrink-fitting. Some tests were devoted to friction coefficient estimation, thus also assessing the lubricating properties of the adhesive. Particularly, dry couplings and couplings and de-couplings with not yet cured adhesive were run to address this point. The results were processed by statistical methods, to assess the influence of the studied factors on the adhesive strength.

Lightweight Wheel Bearing with Dissimilar Materials for Vehicle

<div class="section abstract"><div class="htmlview paragraph">Limited fossil fuel resources, air pollution, and global warming all drive strengthening of fuel economy and vehicle emission standards globally. Much R&D continues to be dedicated to improve fuel efficiency of automobiles and to reduce exhaust gasses. These include improvement of engine/driveline performance for higher efficiency, development of alternative energy, and minimization of air resistance through aerodynamic design optimization. OEM weight reduction-focused research has extended into chassis components (steering knuckle, brakes, control arms, etc.) in sequence from body-in-white(BIW). Wheel bearings, one of the core components of a driveline and part of a vehicle’s unsprung mass, are also being required to reduce weight. Conventionally, wheel bearings have achieved “lightweighting” primarily through design optimization methods. They have been highly optimized today using steel based materials. Opportunities for further mass optimization are increasingly limited and so the focus of this study is integration of lighter-materials into steel bearing components for weight savings. Both aluminum and CFRP were considered in the study for partial integration into the steel hub flange which interfaces directly with the wheel. The application of lightweight materials was targeted on the specific area of the hub which is relatively less affected by impact loads. Hot forging and compressive molding were applied to induce denser bonding of the dissimilar materials. The slope angle design having an inverse draft at the combined boundary was applied to reinforce physical bonding and to enhance joint integrity. In addition, a Zinc-based coating was partially applied on the surface of the combined boundary to protect against galvanic corrosion between dissimilar materials. Bearings containing the new composite hubs achieved a 20% weight reduction compared to conventional wheel bearings made of full steel.</div></div>

Prediction of Natural Frequency of Gas Turbine Disc

In the present paper, Natural frequencies of gas turbine disc determined by Holzer’s method as well as Fast Fourier Transform spectrum analyzer are compared. Hub is a circular disc made up of Aluminium alloy to whose outer periphery blades are welded. Disk’s inner end is coupled with a shaft. Thus the Natural frequencies of this component can be kept at a minimum range. Also this material exhibits good properties such as low embrittlement, low toxicity, easy formation of complex shapes and some other economical issues. Many gas turbine models have adopted mild steel hub. Reduction of torsional vibrations in the circular disc results in decreased Natural frequency of gas turbine assembly. This paper also discuss the information to find stiffness, damping ratio and amplitude.

Research on Dynamic Behavior of Different Grinding Wheel Hub Material with FEM Method

This paper presented a numerical model of a grinding wheel hub to analyze the dynamic behavior between CFRP hub and steel hub. Natural frequencies of the two different hubs were extracted with the help of finite element software ABAQUS. In addition, the vibration attenuation procedure in the process of free vibration of the hubs was also compared. The numerical results obtained from the model demonstrated that natural frequency of the CFRP hub is much higher than that made of steel owing to the great ratio of elastic modulus to density of carbon fiber. The CFRP hub has a better damping vibration characteristic which allows it to absorb vibration in grinding process to achieve a finer surface roughness.

Paediatric vascular access

### Key points Obtaining reliable vascular access in small children is frequently made challenging by anatomical factors—in particular, small, mobile veins and an excess of subcutaneous fat which make visualization and palpation of veins difficult. Paediatric patients are often less co-operative, and the potential for psychological trauma, especially with repeated procedures in the conscious patient, further complicates matters. Short-term vascular access is frequently required in hospitalized children for the delivery of i.v. fluids, medication, and blood product administration. Longer-term vascular access devices are required for repeated medication delivery (e.g. enzyme replacement therapy in inherited metabolic diseases), chemotherapy, immunotherapy, total parenteral nutrition, and extracorporeal procedures such as plasmapheresis and haemodialysis. In addition, vascular access devices may be needed for repeated blood sampling and invasive haemodynamic monitoring. The choice of vascular access device depends upon the condition and preference of the patient or parent/guardian, the likely duration and frequency of treatment, and the properties of the infusate. Infusates with vesicant properties (drugs with the potential to cause blistering with tissue injury, e.g. calcium solutions and amphotericin B), hypertonic solutions, and those with pH 9 will necessitate central venous access. Vasopressors and inotropes are preferentially administered centrally as they require reliable access and extravasation may cause tissue necrosis. It is important to try to predict future needs for vascular access as poor prospective management …

Characterization of a shape memory alloy interference coupling

A versatile and heretofore unutilized coupling is obtained by press-fitting a hollow nickel titanium shape memory alloy (SMA) shaft into a steel hub. This produces an SMA interference coupling that is distinct from other SMA actuators by the method in which the SMA is used. Press-fitting the hollow SMA shaft in its detwinned martensitic phase into a steel hub creates a joint capable of holding parts such as emergency doors, satellite solar panels, or tamper locks securely together until commanded release. Release is accomplished by heating the SMA to its activation temperature. The resulting decrease in diameter of the hollow SMA shaft allows it to easily slip out of the hub, releasing the part. Load testing of the SMA interference coupling showed ultimate strengths about twice that of traditional press-fit coupling strength calculations. The coupling can be designed to be a simple mechanism of very small size, on the order of one cubic centimeter, capable of achieving coupling strengths in excess of 4000 N (900 lbf).

Radial Fatigue Analysis of Steel Hub Based on Finite Element Analysis

The fatigue strength of the steel hub is important to the safety of the automotive wheel and the dynamic radial fatigue test is also one of the three performance experiments for evaluating the safety of automotive wheel. This paper applied Abaqus in analyzing the static strength of the 13×4.5B automotive steel hub according to the test requirement of national standard, and to calculate the hubs fatigue life by Fatigue. Compare the FEA result and the test result, find the two results are very closer which proved the correctness of the static strength analysis and the fatigue strength analysis, and the FEA simulation can efficiently predict the fatigue life of automotive wheel and it does a good for the wheel design to reduce the design cost and to shorten the development cycle.

The Influence of the Leading Wheel Structural Change on Stress of Multi-Rope Friction Hoist

To avoid the open problems of the leading wheel and get a more rational structure, the paper uses PRO / E and the finite element software to analyze the leading wheel of JKM-3.25/4 multi-rope friction hoist. The results show that in the leading wheel the rib plates between the channel steel and wheel hub are removed or added the same ones will have little effect on the overall force situation, and only affect the stress of the weld bead. To solve the problem of open weld of rib plates, can consider the rib plates to be removed. When the radial angle between support wheel and drum is bigger than 6°, the overall force of the leading wheel is affected seriously. But when the radial angle is 5°, the amplitude of stress fluctuation is the minimum, which can improve the leading wheel working conditions and increase the service life of the leading wheel. Therefore the suggestion is to take the radial angle of 5° when to design the new multi-rope hoist. Study conclusions provide the theoretical supports for the leading wheel of multi-rope friction design and technical renovation.

Radial fatigue analysis method of steel hub based on partitioned seam weld model and a new pressure distribution regulation

Steel hub’s radial fatigue simulation is a challenging task in finite element (FE) analysis for its complex processes and nonlinearity. In this research, radial fatigue process was divided into separate steps according to experiment process and analyzed with FE method by sequence. Pressure distribution between tire and hub were summarized and a new pressure distribution regulation distinguishing the inflation stable pressure and the press variable pressure on bead seat and flange was presented. Different material tests were carried out to research the fatigue failure mechanism and properties. A partitioned seam weld modeling method was presented according to the microshear test. Finally, hub’s radial fatigue life was predicted by a 3D FE model with new pressure distribution regulation and partitioned seam weld model. Simulation result matched experiment well which proved the reliability of this method.

Development of a Cornering Bench Fatigue Test for the Validation of a Lightweight Commercial Vehicle Front Hub

Laboratory testing to validate the performance of vehicle components is a common practice in the automotive market. However, during standard bench testing of a commercial front wheel hub, several failures occurred in unexpected regions indicating an inconsistency with the vehicle cornering tests. This article addresses this inconsistency and presents methods for fatigue assessment using an accelerated rig (bench) test for a lightweight commercial vehicle front wheel hub. A complete cornering (figure of eight) vehicle test is modeled on a multi-body dynamic simulation system (ADAMS/Chassis) and the results are compared with the actual data obtained from the hub of a vehicle instrumented with a set of wheel force transducers. The multi-axial loading condition is successfully simplified due to the dominance of some stress components. Load data from the simulation are processed with the rain flow cycle counting algorithm. Critical locations on the C55 steel hub are determined with the stress analysis done on ANSYS (ANSYS Theory Reference: Release 10.0, 2005). Total damage is estimated by using the Palmgren–Miner linear damage summation rule. Finally, some validation test results are consistent with vehicle tests and may be used to substitute performance.

A model for estimating penetration depth of laser welding processes

Penetration depth is one of the most important factors critical to the quality of a laser weld. However, no on-line, non-destructive method exists by which to inspect this quantity. Indirect, model-based estimation schemes are feasible solutions for monitoring laser welding processes. In this paper, a model for estimating penetration depth based on a 2D heat conduction model and a conical keyhole assumption is developed. This model relates the penetration depth to the incident power and the Péclet number, which is a function of the welding speed, the keyhole radius and thermal diffusivity. The Péclet number is determined by measuring the weld width on the top surface. The model is validated by a number of laser welds made to join a low-carbon steel hub and plate assembly using a 5 kW laser with different combinations of power and speed. The results show that the proposed model is consistent with the experimental data and is computationally efficient. Therefore, this model is suitable as a basis for model-based, on-line depth estimation schemes.

Corrosion behavior of decorative car parts and outdoor lighting fixtures fabricated from TiN-coated stainless steel

The fabrication of TiN-coated decorative car parts and lighting fixtures by deep drawing from a TiN-coated stainless steel plate were investigated. Corrosion tests in real and laboratory environments were performed and the behavior of car wheel hub caps coated either before or after forming were compared with uncoated stainless steel hub caps. The micro- and surface structures of the hub caps were studied, before and after the corrosion tests, using secondary-ion mass spectrometry and scanning electron microscopy.

Energy Production and Performance of a Wind-Driven Induction Generator

ABSTRACT A modern wind turbine, an Enertech Model 44/25*, was installed on May 26, 1982, at the USDA Conservation and Production Research Laboratory, Bushland, TX. The wind machine, acquired for a determination of agricultural applications, had a 25-kW induction generator which provided 240 V, 60 Hz, single-phase electric power. The horizontal-axis wind turbine had a 13.4-m diameter, three-bladed, fixed-pitch rotor and was mounted on a 24.4-m tower. The blades were laminated epoxy-wood attached to a steel hub. The wind turbine operated 64% of the time, and was available for operation over 95% of the time. The unit had a net energy production of over 100,000 kW-h for a 20-month period in an average windspeed of 5.9 m/s at a height of 10 m. Power curves were established for the wind turbine at two different pitch settings and with two different sets of blade-tip brakes..