AUBERT & DUVAL CNS (35NiCr6)

Aubert and Duval CNS (35NiCr6) is a medium-carbon, nickel-chromium, direct hardening alloy steel. It is a medium hardenability steel in the 0.30 to 0.37 mean carbon content classification. This steel is frequently used for water-quenched parts of moderate section size and for oil-quenched parts of small section size. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on casting. Filing Code: SA-878. Producer or source: Aubert & Duval S.A. (a member of the Eramet Group).

Design, Construction and Evaluation of an Oscillating Vane Gust Generator for Atmospheric Flow Simulation

The study of unsteady aerodynamic phenomena in wind tunnels is supported by gust-generating devices capable of generating adjustable magnitude and periodicity velocity fluctuations in a flowfield. Gusts are typically generated actively by introducing moving vanes to direct the flow, or passively by tailoring the boundary layer growth and shape in the tunnel. The flow facility used here is a student-built closed-return low-speed wind tunnel, with a test section size of 750 mm × 750 mm and a maximum speed of 25 m/s. A two-vane gust generator utilizing NACA0018 airfoil sections of 150 mm chord length was designed and installed upstream of the test section. The flowfield was mapped with the installed vanes with and without gust actuation, utilizing a hot wire system. The tunnel with gust vanes exhibits a spatially uniform baseline turbulence intensity of 5%, with a steady state velocity deficit of 1 m/s in the vane–wake region. Upon introducing the gusting conditions at vane deflection angles of up to ±45°, velocity differences of up to 4 m/s were attained at 18 m/s freestream velocity at oscillation frequencies ranging between 1 Hz and 2 Hz.

RESULTS OF EXPERIMENTAL STUDIES OF THE PROCESS OF CUTTING SOFT WOOD WITH DISC KNIVES

Stamping of softwood is still a poorly researched process of chipless division. The research on commercially available equipment was carried out. Multivariate experiments were held according to standard methods with the number of measurements from 20 to 150 using softwood including conifers. A computer was used to substantiate the obtained coefficients of the regression equations. The magnitude of external factors such as loading mode, duration and the introduction of plasticizers were studied. Exploratory experiments made it possible to accurately establish the magnitude of the external load during direct and oblique collapse, as well as the optimal deformation temperature. Moreover, the studies were carried out taking into account the different moisture content of the wood. Regression models for four factors with two outputs were obtained. Insignificant coefficients were excluded and further research of the influence of humidity, temperature, section size and shape of the work piece on the surface quality of stamped parts were carried out. As a result, the dependence of the magnitude of deformations in wood on load and temperature was built. Solving the optimization problem made it possible to identify the following parameters of the processes of stamping softwood: density within 400 kg/m3 and temperature 156 degrees Celsius

Understanding Cooling Rate Response of Test Pieces and Actual Gears Using Heat Treat

The cooling history of carburized heat-treated gears plays a significant role in developing microstructure, hardness, and residual stress in the tooth that influences the fatigue performance of the gear. Evaluating gear carburizing heat treatment should include a microstructure and hardened depth evaluation. This can be done on an actual part or with a test piece. The best practice for a test piece is to use a section size that closely approximates the cooling rate at the gear flank of the actual gear. This study furthers work already presented showing the correct test piece size that should be used for different gear modules (tooth thicknesses). Metallurgical comparisons between test pieces, actual gears, and FEA simulations are shown.

LUCEFIN 25CrMo4 (1.7218), 25CrMoS4 (1.7213)

Lucefin 25CrMo4 and 25CrMoS4 are low-carbon, chromium-molybdenum direct hardening alloy steels. These low hardenability steels are used for water-quenched parts of moderate section size and for oil-quenched parts of small section size. In general, these steels are used for parts requiring high strength and toughness. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: SA-874. Producer or source: Lucefin S.p.A.

Simulasi ETAP 12.6 untuk Studi Instalasi Listrik pada Kereta Api Kahuripan

AbstrakDalam sebuah satu rangkaian kereta biasanya terdiri dari penggerak utama lokomotif, kereta penumpang, kereta makan, dan kereta pembangkit. Dengan banyaknya fasilitas dan alat-alat kelistrikan dalam gerbong-gerbong tersebut dapat memberikan dampak penurunan terhadap kualitas daya listrik yang mengalir pada sistem distribusi aliran daya. Penelitian ini bertujuan untuk mengetahui kapasitas nilai circuit breaker, ukuran penampang kabel, tegangan jatuh, dan rugi-rugi daya, serta perbandingangannya dengan hasil simulasi pada software ETAP 12.6. Kapasitas circuit breaker dan ukuran penampang kabel yang diperhitungkan mendapatkan rating circuit breaker dengan arus berkisar dari 800 hingga 80 Ampere dan ukuran kabel yang digunakan sebesar 120 mm2. Hasil nilai drop voltage yang didapat dimulai dari 1,02 Volt hingga 5,08 Volt. Untuk nilai rugi-rugi daya yang didapat dimulai dari dari 0,01 kW hingga 0,11 kW.Kata kunci: Aliran Beban, ETAP, Circuit Breaker, Drop Voltage, Rugi-rugi Daya.AbstractA train usually consists of several carrieges: a prime mover locomotive, passenger carriage, dining carriage, and generator carriage. With that many facilities and installed electrical equipments the quality of the electric power flowing in the trains’s power distribution system may be decresed. This study aims to determine the capacity of the circuit breaker, the cable’s cross section size, the voltage drop, and power losses, as well as the comparison with the simulation results by using ETAP software. The circuit breaker capacity and cable’s cross-sectional size are calculated. From the calculations, we obtain the rating value for the circuit breaker, which is ranging from 800 to 80 Ampere. As for the cable’s corss sectional we obtain 120 mm2. With these values, the resulting voltage drop is from 1.02 Volts to 5.08 Volts. As for the resulting power loss, its value is ranging from 0.01 kW to 0.11 kW.Keywords: Load Flow, ETAP, Circuit Breaker, Voltage Drop, Power Loss.

Study on Asymmetric Failure and Control Measures of Lining in Deep Large Section Chamber

Lining is often used as the last line of defense in deep large section chamber. Under the asymmetric load, it is easy to damage, resulting in the overall repair of the chamber. Aiming at this problem, taking the pump house in Wanfu Coal Mine under construction in China as an engineering example, we analyzed the asymmetric failure of pump house lining caused by construction disturbance, established the lining mechanical model and quantitative evaluation indexes, such as bending moment change rate, bending moment balance rate, displacement change rate and displacement balance rate, studied the influence mechanism of asymmetrical coefficient, section size and lining thickness on the mechanical behavior of lining, and proposed the control measures of deep large section chamber with the core of “strengthening asymmetric support, reducing section size and improving lining strength”. The field monitoring shows that the asymmetric deformation of the pump house is effectively controlled, and the maximum displacement is only 7.3 mm, which ensures the long-term stability of the chamber.

CEN 34Cr4 (1.7033), 34CrS4 (1.7037)

CEN 34Cr4 and 34CrS4 are medium-carbon, 1% chromium, direct hardening alloy steels that are also suitable for flame and induction hardening. These steels are low hardenability steels in the 0.30 to 0.37 mean carbon content classification. They are used for water-quenched parts of moderate section size and for oil-quenched parts of small section size. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on forming, heat treating, and joining. Filing Code: SA-872. Producer or source: European Committee for Standardization.

Prediction and Analysis of Ultimate Bearing Capacity of Square CFST Long Column under Eccentric Compression after Acid Rain Corrosion

This paper adopts the method of steel tube wall thickness and strength reduction to simulate corrosion damage. The numerical model of the square concrete-filled steel tube long column (SCFST-LC) under eccentric compression after acid rain corrosion is established in the finite element software, ABAQUS. The reliability and accuracy of the model are verified by comparing it with published relevant experimental results. The failure mode, load-deformation curve, and ultimate compressive load were analysed. Following that, the impacts of section size, yield strength of the steel tube, axial compressive strength of concrete, steel ratio, slenderness ratio, and load eccentricity on its ultimate compressive load are comprehensively investigated. The results demonstrate that the ultimate compressive load of the SCFST-LC decreases significantly with the increase in corrosion rate. The corrosion rate increases from 10 to 40%, and the ultimate bearing capacity decreases by 37.6%. Its ultimate bearing capacity can be enhanced due to the increase in section size, material strength, and steel ratio. In contrast, the ascending slenderness ratio and load eccentricity has harmful effects on the ultimate compressive load of the specimens. Finally, a simplified formula for the axial compressive load of the SCFST-LC under eccentric compression after acid rain corrosion is proposed. The calculation accuracy is high and the deviation of the results is basically within 15%, which is in good agreement with the numerical simulation results.

Experimental and Analytical Study on Creep Characteristics of Box Section Bamboo-Steel Composite Columns under Long-Term Loading

To expand the application of bamboo as a building material, a new type of box section composite column that combined bamboo and steel was considered in this paper. The creep characteristics of eight bamboo-steel composite columns with different parameters were tested to evaluate the effects of load level, section size and interface type under long-term loading. Then, the deformation development of the composite column under long-term loading was observed and analyzed. In addition, the creep-time relationship curve and the creep coefficient were created. Furthermore, the creep model of the composite column was proposed based on the relationship between the creep of the composite column and the creep of bamboo, and the calculated value of creep was compared with the experimental value. The experimental results showed that the creep development of the composite column was fast at first, and then became stable after about 90 days. The creep characteristics were mainly affected by long-term load level and section size. The creep coefficient was between 0.160 and 0.190. Moreover, the creep model proposed in this paper was applicable to predict the creep development of bamboo-steel composite columns. The calculation results were in good agreement with the experimental results.