Iron Shaft Research Articles

The effects of different iron shaft weights on golf swing performance.

This study examined the effects of three 7-iron shaft weights on golf swing performance among golfers of varying skill levels. The study included 10 low-handicap (LH; 4.3 ± 2.4) and 10 high-handicap (HH; 29.1 ± 5.4) right-handed golfers as participants. The participants were randomly assigned 7-iron clubs with shaft weights categorized as light (77g), medium (98g), or heavy (114g), and they performed test shots. Kinematic data were captured using a motion analysis system with nine infra-red high speed cameras; a force platform connected to this system was used to record weight transfer patterns. Performance variables were assessed using a FlightScope launch monitor. A two-way mixed-design analysis of variance was used to determine the significance of the performance differences among both participant groups and golf shaft weights. The results indicated that during the backswing, the LH group exhibited significantly greater maximum rightward upper torso rotation, maximum X-factor, and maximum right wrist hinge rotation than did the HH group. During the downswing, the LH group exhibited significantly greater maximum upper torso angular velocity and maximum right wrist angular velocity than did the HH group. Moreover, the LH group produced significantly higher ball speeds, longer shot distances, and lower launch angles than did the HH group. The shaft weight neither greatly altered the golf swing nor displaced the center of gravity of the golfers. The lighter shafts were observed to facilitate faster clubhead speeds and initial ball velocities, thereby resulting in longer shot distances, especially among LH golfers. Although significant differences in swing mechanics and performance exist between HH and LH golfers, lighter shafts can contribute to increased shot distances for all golfers.

An axial flux eddy current sensor with perpendicular coils for speed measurement

This paper presents an axial flux eddy current sensor with a compact and simple structure for measuring the rotating speed of iron shafts. The sensor structure is optimized for high sensitivity with a novel configuration of the coils positioned perpendicularly to each other. The sensor comprises two D-shaped excitation coils and two D-shaped pick-up coils in a double-layer structure. A disc-shaped magnetic shield or core shields the coils. Two iron shafts with different material properties are considered. A new cup-shaped configuration of nonmagnetic copper and aluminum caps mounted on iron shafts improves sensitivity and suppresses susceptibility to shaft material properties and airgap variation. 2D and 3D finite element methods are utilized for the performance analysis of the sensor. The measurements are performed at speeds up to ± 3000 rpm and different excitation frequencies from 400 Hz to 4 kHz. The eddy current speed sensor has excellent linearity characteristics with a nonlinearity error of 0.15%. The geometry of the coils is further optimized and improved for maximum sensitivity and compactness. The fault-tolerant capability of the sensor is also evaluated.

Operating characteristics and design parameter optimization of permanent magnet linear generator applied to free-piston energy converter

A tubular permanent magnet linear generator (PMLG) with axial magnetized is proposed for the free-piston engine generator (FPEG). The structures and test rigs of the PMLG and FPEG prototypes are introduced. The working characteristics of the PMLG in FPEG system are analyzed under ignition conditions. A 2D finite element model of the PMLG is designed and verified based on initial design parameters and test results. The influences of key operating parameters on the output performance of PMLG are studied. On these basis, when considering the actual motion characteristics of the PMLG in FPEG system, the effects of different structural parameters on the power generation performance and efficiency (h) are investigated. Results show that when the working frequency of the FPEG is relatively small, the displacement profile resembles a sinusoidal curve. As the working frequency and stroke length increase, the power generation increases rapidly. As the air gap length and back iron shaft diameter decrease, and the stator slot number increases, the output voltage (U), current (I), power (Pout), and total loss power (Ploss) show an approximately linear increasing trend. As the pole arc coefficient and stator tooth width increase, the U, I, Pout, and Ploss first increase and then decrease. As the stator yoke thickness increases, the U, I, and Pout increase rapidly and then tend to stabilize. Besides, these structural parameters have little impact on power generation efficiency of this PMLG.

Decarbonising the iron and steel industries: Production of carbon-negative direct reduced iron by using biosyngas

Bioenergy with carbon capture and storage (CCS) in iron and steel production offers significant potential for CO2 emission reduction and may even result in carbon-negative steel. With a strong ambition to reach net-zero emissions, some countries, such as Sweden, have recently proposed measures to incentivise bioenergy with CCS (BECCS), which opens a window of opportunities to enable the production of carbon-negative steel. One of the main potential applications of this route is to decarbonise the iron reduction processes that account for 85 % of the total CO2 emission in the iron and steel plants. In this study, gasification is proposed to convert biomass into biosyngas to reduce iron ore directly. Different cases of integrating the biomass gasifier, Direct Reduced Iron (DRI) shaft furnace, and CCS are evaluated through process simulation work. Based on the result of the work, the proposed biosyngas DRI route has comparable energy demand compared to other DRI routes, such as the well-established coal gasification and natural gas DRI route. The proposed process can also capture 0.65–1.13 t of CO2 per t DRI depending on the integration scenarios, which indicates a promising route to achieving carbon-negative steel production.

An Axial Airgap Eddy Current Speed Sensor

This article presents a novel configuration of the eddy current speed sensor to measure the rotating speed of iron rods and shafts up to 3000 r/min. The proposed eddy current speed sensor has an axial airgap structure with one excitation coil and two antiserially connected pick up coils. The speed sensor is mounted in the end shaft part region. Different solid iron materials for rotating shaft are considered in the measurements and calculations to evaluate solid iron material effect on the eddy current speed sensor performance. Two-dimensional (2-D) and 3-D finite element method is utilized for the performance analysis of the speed sensor. Also, a 2-D analytical method is developed for parametric analysis. A copper rod is also used to compare the speed sensor with the rotating iron shaft and copper shaft. Finally, two thin copper discs with different diameters are mounted on the solid iron shaft and their influences on the eddy current speed sensor were evaluated and measured to increase sensitivity and decrease sensor dependency on the permeability of the solid iron shaft. The achieved nonlinearity errors are about ±0.2%.

Assessment of Shaft Surface Structures on the Tribological Behavior of Journal Bearings by Physical and Virtual Simulation

Optimizing the surface topography of cast iron crankshafts offers the opportunity to use this material as an alternative to steel in high-performance combustion engines. In the past, this was not possible due to the higher wear on bearing shells and the higher friction losses in relation to forged steel shafts. In order to find an optimized shaft micro topography, the friction and wear behavior of steel and cast iron shafts with different surface treatments were compared to each other, using a combined physical (experimental) and a virtual (computational) simulation approach. The experiments were carried out with a rotary tribometer using a journal bearing test configuration with the possibility to test real-life bearing shells and shaft specimens, manufactured from real-life crankshafts. In the experiments, a polished steel shaft with low bearing wear was effective. The optimization of cast iron crankshafts by a novel surface treatment showed a significant reduction of bearing wear in relation to the classical surface finishing procedures of cast iron shafts. A computational simulation approach, considering the real-life micro topography by using the Navier–Stokes equations for the calculation of micro hydrodynamics, supports the assessment of fluid friction. The virtual simulation shows, in accordance to the experimental results, only a minor influence of the investigated shaft topographies on the fluid friction. Further optimization of shaft surfaces for journal bearing systems seems possible only by the usage of patterned micro topographies.

Development of an axial-flux self-bearing motor using two permanent magnet attractive type passive magnetic bearings

This paper introduces an axial-flux self-bearing motor (ASBM) using two permanent magnet attractive type passive magnetic bearings (PMBs). The ASBM provides both functions of a disc motor and thrust magnetic bearing, and controls motor torque and axial force by single rotational magnetic flux. The PMB consists of a cylindrical permanent magnet and an iron shaft with conical edge, and it supports the rotor in radial directions. This motor has a simple structure and control system, and it is possible to reduce the size and cost. In this paper, the structure and control method are introduced, and the results of levitation and rotation tests whose non-contact rotation speed was achieved up to 1,500 rpm are shown.

Striking Iron: The Art of African Blacksmiths

Striking Iron: The Art of African Blacksmiths

Development of Non-Contact Levitated Rotating Machine Using HTS Bulks and Permanent Magnets

We have studied a non-contact magnetic levitation system using ring-shaped high-temperature superconducting (HTS) bulks and ring-shaped permanent magnets (PMs). Because the HTS bulks were magnetized by PMs fixed between the HTS bulks, this PMs levitated with strong restoring force. We used a stator coil to rotate the iron shaft combined with PMs. In order to rotate the shaft stable, restoring the force of radial direction is very important. Therefore, the ring-shaped PMs magnetized in the radial direction were fitted to the shaft. In this rotating system, we focused on two parameters, i.e., the rotation and the control. In the rotation, we measured the maximum rotating speed and the axial vibration due to the rotating speed. The three types of stator coils were designed by electromagnetic analysis, and these stators were tested experimentally.

Bronze mace with three rams' heads from Ashmolean Museum, University of Oxford

The present study brings to light a new Sasanian mace in the Ashmolean Museum in Oxford, England, acquired in 1971 from the Bomford Collection. The bronze mace head is in the shape of three ram heads, has an iron shaft, and a bronze pommel in the shape of a hand holding a ball. The mace incorporates several important decorative motifs – the ram heads which can be linked to the royal farr and to Central Asian visual language; the pearl necklace which is another symbol of the royal farr, and the triple dot motif which may have links to the star Tishtriya, to Apam Napat, or to Buddhist symbolism. In addition to these elements there is the hand motif, whose meaning is still unknown but might be linked to Asian symbolic hand gestures. The mace or scepter was an important element of royalty and of religion in Iran and Central Asia and the example in the Ashmolean museum is an important addition in the study of Iranian visual language and royal image in the specific context of Indo-Iranian mutual influence. In the present authors' opinion, the present mace is likely to date, based on relations with other objects, from the 5th - 7th Centuries and is likely to originate from Eastern-Iran or is rooted in Eastern-Iranian artistic tradition.

Tribological study of crankshaft bearing systems: Comparison of forged steel and cast iron counterparts under start–stop operation

The current work investigates the tribological functionality of crankshafts bearing systems focusing on the variation of shaft materials and their surface conditions. Tribological tests were carried out with a ring-on-disc test configuration representing the bearing-shaft contact under start–stop motion. Forged steel and cast iron shaft materials were sliding against an Al based bearing alloy. The surfaces in contact were analyzed by light and electron microscopy subsequently. The performance of forged steel depends on the overall roughness of the surface, whereas the tribological functionality of cast iron is mainly determined through its microstructure and the occurrence of metal flaps with burrs. The results prove the significance of proper surface finishing of forged steel and cast iron shaft materials in order to minimize wear in journal bearing systems. For both shaft materials good sliding performances with respect to optimized surface finishing can be noted.

The Levitation Characteristics of the Noncontact Rotating System Using HTS Bulks Trapped by Permanent Magnets

We have studied a noncontact magnetic levitation system using the ring-shaped high-temperature superconducting (HTS) bulks and ring-shaped permanent magnets (PMs). Because HTS bulks were magnetized by PMs fixed between the HTS bulks, these PMs levitated with strong restoring force. We used the stator coil to rotate the iron shaft that was combined with PMs. In order to rotate the shaft stable, a restoring force of the radial direction was important. Thus, we placed ring-shaped PMs that magnetized in the radial direction with the inner part of the HTS bulks. In this rotating system, we focused on two parameters, the rotation and the control. In the rotation, we measured the maximum rotational speed and the axial vibration caused by increasing of rotational speed. In the control, we measured slippage from the convergence position when rotated by 60°. In addition, we compared the slippage by changing the conditions.

The Study of the Ventilation Influence to Gas-Based Direct Reduction Shaft Furnace Flow Field

Direct reduced iron (DRI) shaft furnace flow field has important influence to the DRI production process, and the ventilation is a key factor for the velocity and pressure distribution of the gas flow in the furnace. At present works, the direct reducing gas velocity distribution and pressure distribution of DRI shaft furnace were studied with different ventilation. By the analysis of numerical simulation, the result was found that the direct reducing gas velocity increase with height in the shaft furnace reduction section. The velocity of the direct reducing gas augment with the increase of ventilation. The direct reducing gas pressure add with increasing height in the shaft furnace reduction section. With ventilation increasing, the pressure of the shaft furnace ventral part increase, and the pressure gradient increase in the direction of height in the DRI shaft furnace.

Internal DLC coating of narrow metal tubes using high-density near plasma sustained by microwaves propagating along plasma–sheath interfaces

Recently, internal plasma processing of narrow halls and tubes is strongly desired in industry. Uniform processing of such a 3-dimensional metal surface by plasma is typically achieved by RF and DC glow discharge where negative voltage is applied to a metal substrate against a grounded chamber at low gas pressures. However, the plasma electron density, ne of RF and DC plasmas is typically no more than 109–1010cm−3 at low pressure, and thus plasma cannot be steadily sustained inside narrow halls and tubes less than 1cm in width. For successfully processing the internal surface of such narrow halls and tubes with plasmas, it is essential to employ higher-density (ne>1011cm−3) plasma. Therefore, we proposed a new method to generate high-density plasma along 3-dimensional metal surfaces by using microwave propagation along plasma-sheath interface, and further demonstrated that high-density plasma column can be steadily sustained inside a narrow metal tube whose inner diameter is in the range of millimeters and the length is more than 10 times of it. In this work, we tried to deposit diamond-like carbon (DLC) film onto the inner surface of a stainless-steel tube 4.4mm in inner diameter and 50mm in length by applying the new method. The tribological properties of the DLC film were then investigated, by conducting a rotational friction test of the DLC coated tube against a cast iron shaft under dry condition; as a result, the minimum friction coefficient of 0.17 was obtained at the position 40mm distant from the bottom end of the tube where microwaves are injected during deposition. However, the friction coefficient was 0.4 at the rest positions (10 and 25mm from the bottom end), where the films were peeled off the substrate during the friction test.

The decorative bell capital of the Delhi iron pillar

The design and construction of the decorative bell capital of the 1,600 year old Delhi iron pillar attests to the high degree of skill of the ancient Indian blacksmiths in working iron. Detailed visual observations clearly establish that the decorative bell capital is not a single piece of metal, but is composed of separate pieces that have been individually constructed by forge welding. A critical analysis of the fitting methodology of the Delhi iron pillar’s decorative top indicates that the individual pieces were fit around a cylindrical hollow iron shaft, which was connected to the main body of the pillar by means of an insert.

Seizure Resistance of Aluminum-Lead-Silicon Connecting Rod Bearings and Nodular Cast Iron Shafts

Seizure failure of aluminum-lead-silicon crankshaft bearings and nodular cast iron shafts has been studied experimentally. Bearings and shafts of different materials with different surface texture have been tested and compared. Results show that seizure can occur on micro, local and failure scales. Larger silicon particles in the bearing alloy give better seizure resistance. Bored bearings have higher seizure loads than broached bearings. Fertile in cast iron decreases the seizure resistance of the shaft. Surface quality of the shaft also has an apparent effect on the seizure limit. Hypotheses are proposed to explain seizure behaviors and mechanisms. Presented at the 50th Annual Meeting in Chicago, Illinois May 14–19, 1995

Study on aluminum alloy bearings containing hard particles.

High tin and aluminum alloy bearings can seize easily when used with nodular cast iron shafts. The process of seizure is studied and it is found that the burrs left around the graphite on the surface of the nodular cast iron shafts abrade the aluminum alloy and that embeded debris causes further transfer of the aluminum alloy, which leads to eventual seizure. In an attempt to remove the burrs and transferred aluminum alloy during operation, hard particles of Si are dispersed in the alloy bearings. This arrangement provides much higher seizure resistance than the conventional aluminum alloy bearings in sliding against nodular cast iron shafts.

Effects of hardness of particulate inclusions dispersed in aluminum alloy bearings.

Hard particulate inclusions can improve the seizure resistance of aluminum alloy bearings through a mild lapping action, when used with nodular cast iron shafts. In the present paper, the effects of hardness of the particulate inclusions are studied. A mixed lubrication tester is used to evaluate friction and wear properties of four alloys with inclusions of varying hardness. The wear amount is least and low friction appears at the earliest stage with hard Si particles. while softer inclusions show larger amounts of wear as well as prolonged periods of initially higher friction.

Effects of hard particles added to aluminum alloy bearings.

High tin aluminum alloy bearings can seize when used with nodular cast iron shafts in automotive engines. In an attempt to remove burrs and transferred aluminum debris which cause the seizure from the surfaces of the shafts, hard Si particles are dispersed in the alloy bearing, which provides much higher seizure resistance than in the conventional aluminum alloy bearings. The hard Si particles show mild lapping action to the shaft surfaces, as well as removal of transferred aluminum debris on them. To maximize the action of hard Si particles, the effects of amount and shape of the Si particles are studied. The effects of shape is critical and it is found that the seizure resistance becomes far higher when the particles are lumpy. The flaky Si particles are broken during the test and the removing action is minimized leading to a lower seizure resistance.