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A ‘locking-bolt’ demountable shear connector (LBDSC) is proposed to facilitate the deconstruction and reuse of steel-concrete composite structures, in line with achieving a more sustainable construction design paradigm. The LBDSC is comprised of a grout-filled steel tube and a geometrically compatible partially threaded bolt. The latter has a geometry that ‘locks’ the bolt in compatible holes predrilled on the steel flange and eliminates initial slip and construction tolerance issues. The structural behaviour of the LBDSC is evaluated through nine pushout tests using a horizontal test setup. The effects of the tube thickness, strength of concrete slab, and strength of infilled grout on the shear resistance, initial stiffness, and ductility of the LBDSC are assessed. The experimental results show that the LBDSC can achieve higher shear resistance and similar initial stiffness as compared to traditional welded studs. In addition, all tested LBDSCs exhibited slip capacities ranging from 14 to 32 mm and can be classified as ductile shear connectors according to Eurocode 4. A detailed finite element model was also created and found to be reliable to reproduce the experimental behaviour. Parametric studies were subsequently conducted using the validated model to study further parameters and generalise the experimental results. Due to the specific test setup, non-negligible uplift forces were generated in the connector and the potential implications are discussed.

Stainless steel (SS) is increasingly used for structural applications in the construction industry as its beneficial properties outweigh initial material costs when sustainability aspects and the whole life cycle of structures are appropriately accounted for in the structural design. Despite the well-recognised significance of connections in bare metallic construction, experimental research on SS beam-to-column connections, especially full-scale test results, are scarce. This paper presents a full-scale experimental investigation on the semi-rigid behaviour of top-seat bolted connection (also known as ‘flange cleat’ connection) made from austenitic SS. Deformation characteristics of various elements of the connection were carefully investigated and subsequently used to calibrate nonlinear FE models for parametric analysis. Obtained numerical results were used to develop a four-parameter power model that relies on simplified expressions for key input parameters to predict the semi-rigid behaviour of bolted top-seat connections. Results predicted using the proposed model and those obtained using currently available techniques based on carbon steel behaviour were compared. Outcomes of the current research highlighted the significance of appropriate inclusion of stain hardening offered by austenitic grade to capture the semi-rigid response of such connections.

The era of the Industrial Revolution 4.0 military power became one of the important elements because technological developments have changed the entire order of military strategy. One of them is the development of military equipment technology part of weaponry. As is known, often Indonesia army soldiers conduct shooting exercises to defend the Nation and the Unitary State of the Indonesian People (NKRI). With the shooting training there is a lot of waste from bullet cladding. Bullet cladding or patrun is an object that is a container that wraps around a bullet projectile and consists of propellant (gunpowder), rim, and primer. Bullets/munitions after firing can still be recycled back into active munitions. In accordance with the purpose of this study, researchers modified a cladding machine in order toimprove the performance of thetool effectively than before. The research methods used are a combination of experimental and empirical manual calculations to determine the relevant results. The result destruction can cut 3 grains of cladding even more in everyone round of the cutting blade, so this study modified the transmission system, fixed clutch, shaft, straight gear. The transmission uses a1:60 wpa gearbox ratio, with an electric motor drive power of 1.5 kW/ 2 HP, 1450 r / min, using a flange type clutch.

This paper proposes a deep-learning framework, specifically, a Deep Belief Network (DBN), for studying the web crippling performance of cold-formed stainless steel channel sections (lipped and unlipped as well as fastened and unfastened) with centered and offset web holes under the end-two-flange loading condition. G430 ferritic, S32205 duplex and 304 austenitic stainless steel grades are considered. A total of 17,281 data points for training the DBN are generated from an elasto plastic finite element model, validated from 69 experimental results reported in the literature. When a comparison was made against a further 53 experimental results reported in the literature, the DBN predictions were found to be conservative by around 10%. When compared with Backpropagation Neural Network (a typical shallow artificial neural network) and linear regression model based on PaddlePaddle, it was found that the proposed DBN outperformed these two methods, using the same big training data generated in this study. Using the DBN predictions, a parametric study is then conducted to investigate the effect of web holes, from which unified strength reduction factor equations are proposed. Finally, a reliability analysis is conducted, which shown that the proposed equations can predict the web crippling strength of cold-formed stainless steel channel sections under the end-two-flange loading condition.

According to the periodical inspection manual for civil infrastructures in Japan, the visual inspection plays a very important role to detect deterioration such as fatigue cracking. Since the steel bridges are covered with paint coating, a fatigue crack is often detected as a crack of the paint. Conventionally, when a paint crack is detected, the paint coating is removed and magnetic particle test is applied. However, it is not always true that there is a fatigue crack under the paint crack. This process is time-consuming, especially when no fatigue crack is detected. The objective of this study is to detect fatigue crack without removing the paint coating by nondestructive technique. Among nondestructive techniques, ultrasonic test was applied, because an internal crack can be detected. This study focused on flange gusset welded joint; lateral connection plates were welded to the base plate from both sides. After being welded, the specimens were painted by either fluorine resin paint or epoxy resin paint. Fluorine and epoxy paints are mainly applied for highway road and railway bridge, respectively. Fatigue tests were carried out for the specimens. During the fatigue test, when strain to monitor crack initiation was changed, ultrasonic test by creeping wave was conducted. The creeping wave is a longitudinal wave that travels very close to the test surface. A fatigue crack of 1.1 by 1.6 mm could be detected by the ultrasonic test.

El puente de estructura mixta que se presenta en este documento, fue desarrollado de manera privada, con el dueño de la propiedad que deseaba unir sus dos terrenos divididos por un afluente. La luz del puente es 12 metros. El puente debía cumplir con soportar un vehículo de carga liviana a capacidad máxima (1.5 ton. en total), según la necesidad del propietario. Por el tiempo y presupuesto , se optó por una estructura de losa de puente en concreto reforzado sobre vigas de acero ASTM A36, ensambladas en sección tipo “I”. El diseño de vigas simétricas en acero se encontró limitado por la flexión, cortante, pandeo local y deflexión. Para el efecto de flexión se consideró la inercia de la viga y su estabilidad torsional, para cumplir con efectos de compacidad en alma y alas. Dentro del proceso constructivo, fue importante la coordinación entre la fabricación de los estribos y las vigas prefabricadas metálicas, el aprovechamiento en cortes de las placas de acero, el proceso de unión, soldadura y lanzado de vigas armadas en obra. Las imágenes muestran un tipo de conector de cortante entre viga y losa, pero el mismo no forma parte del diseño, esta decisión fue tomada considerando la posibilidad a futuro de que el cliente desee usar el puente con un vehículo más pesado y la estructura tenga mayor resistencia por parte del tablero del puente.

The goal of this experimental study is to manufacture a bolted GFRP flange connection for composite pipes with high strength and performance. A mould was designed and manufactured, which ensures the quality of the composite materials and controls its surface grade. Based on the ASME Boiler and Pressure Vessel Code, Section X, this GFRP flange was fabricated using biaxial glass fibre braid and polyester resin in a vacuum infusion process. In addition, many experiments were carried out using another mould made of glass to solve process-related issues. Moreover, an investigation was conducted to compare the drilling of the GFRP flange using two types of tools; an Erbauer diamond tile drill bit and a Brad & Spur K10 drill. Six GFRP flanges were manufactured to reach the final product with acceptable quality and performance. The flange was adhesively bonded to a composite pipe after chamfering the end of the pipe. Another type of commercially-available composite flange was used to close the other end of the pipe. Finally, blind flanges were used to close both ends, making the pressure vessel that will be tested under the range of the bolt load and internal pressure.

An adequate computer model of the process of rolling flange details with inclined rolls has been built in the software package DEFORM-3D. The analysis of the stress-strain state of a detail with a flange was performed. The rheological properties of the alloy L63 (62-65% Cu, 34.5-38% Zn) were experimentally studied. Value limits of the Cockcroft-Latham fracture criterion for the alloy L63 are determined.

To expand the application of wood as a building material, a new type of I-shaped wood-steel beam that consisted of laminated veneer lumber and cold-formed thin-walled steel was considered in this paper. The shear performance of nine wood-steel composite beams was tested to evaluate the effects of shear span ratio, web thickness, and flange thickness. Then, the failure pattern and failure mechanism of the composite beams were analyzed. The main affecting factors of shear capacities were also discussed. Furthermore, the calculation formula for bearing capacities of composite beams was established and the calculation results were compared with the experimental results. The experimental results showed that the combined effect of composite beams was excellent. The shear capacity was mainly affected by shear span ratio and web thickness. The calculation formula of the shear capacity was established based on the shear flow theory and the specification for structural steel buildings. The formula was derived from the micro-segment balance method and the reciprocal theorem of shear stress. The calculation results according to the formula were in good agreement with the experimental values.

Numerical study on structural performance of hybrid stainless steel stub columns are provided in this paper by utilizing finite element (FE) software, Abaqus. Two novel stainless steel grades were used viz., Lean duplex stainless steel (LDSS) and Duplex stainless steel (DSS) for hybrid stainless steel stub columns. The current investigation on hybrid stub columns consist of two configurations: (1) Hybrid stainless steel (HSS) stub column adopting DSS on the flanges and LDSS on the web; and (2) Hybrid stainless steel (HSSa) stub column using DSS and LDSS on the web and flanges respectively. The numerical results are presented in terms of column capacity (Pu) and failure modes. As observed from the investigation, both flange thickness (tf) and flange width (bf) have more influence on the column capacity for HSS stub column as compared to HSSa stub column. On the other hand, increase in web thickness (tw) is found to provide an enhancement in column capacity for HSSa compared to HSS stub column, in contrast to the effect of tf and bf. In general, EN 1993-1-4 Class 3 limit for internal web is observed to be reliable for all stainless steel stub columns. Based on the FE results, new DSM formulation for HSS and HSSa stub columns was proposed based on modified DSM equation for carbon steel.

This article focused on the microstructure characterization and residual stress measurements of the flange from classes D and C railway wheels (called 7D and 7C steel, respectively) to contribute with the residual stress level on new forged wheels flange area. A correlation with the hardness was conducted. The residual stress was measured in three points of the flange using the x-ray diffraction technique, and the microstructure characterization on SEM microscopy. We found the 7C steel has fine pearlite and ferrite microstructures, and 7D steel has degenerated pearlite and bainite microstructures. In the 7D steel, the compressive residual stress in the flange region was higher than in the 7C steel, which is related to the presence of bainite on the microstructure. There was a correlation between the hardness and residual stress value. The knowledge of the residual compression stress level is important for safety train wheels operation. The traction stress generated by the brake system on the wheel is attenuated by residual compression stress.

The paper describes the main stages of the development of sectional and shaped profiles by the JSC “EVRAZ NTMK” over the past years. The plant operates three longitudinal rolling mills, each of which has been producing both construction metal structures and transport products for many decades. Every year, market competition causes increased consumer requirements toward product quality and requires expansion of the product assortment. Therefore, developing new profiles is an ongoing process at the JSC “EVRAZ NTMK.” The following transport profiles have been developed: stirrup stop bar, rail pad bar R-65, insulated joint core bar ApATeK R-65 MK-BO, guard-rail angle SP850, subway conductor rail, I-beam No. 19 used in the construction of a center girder of the pivoted unit of the rail cars, and a non-standard I-beam 13C1 manufactured according to the technical agreement with the Research and Production Enterprise (RPE) “Uralvagonzavod.” Due to consumer requests, the heavy-section and rail-and-beam shops of the JSC “EVRAZ NTMK” started production of the U-channel line, since such series is more preferable when manufacturing metal constructions compared to V-channel sloping along the inner side of the flange, previously produced at the JSC “EVRAZ NTMK.” In recent years, the railand-beam shop started production of the entire line of crane rails. In just the past 5 years, over 60 standard I-beam sizes have been implemented under the wide-flange beam rolling shop conditions according to various standards, including a foreign ASTM A6/A6M-2017a standard and BS EN 10365–2017 standard, as well as GOST R 57837–2017 developed by EVRAZ together with the Central Research Institute of Building Structures (TsNIISK) named after V. A. Kucherenko. The process of developing new profiles at the JSC “EVRAZ NTMK” continues. In 2020 alone, it is planned to start production of more than 20 new types and nominal sizes of the hot-rolled sectional and shaped profiles.

Metro trains often encounter the problem of wheel flange wear when they pass through sharp curves, especially for the poor wheel–rail profile matching or lack of lubrication, evidently increasing t...

A classification of flange connections of chemical production equipment is proposed. The most characteristic designs of these types of flange connections proposed by designers and inventors from different countries around the world over the past 50 years are considered.

Foundries contribute to production of major automotive parts. These foundries now a days suffering from poor quality and productivity due to different parameters of the casting process. Casting quality depends on the solidification process after pouring. Computerized casting modeling and solidification simulation is being extensively used by foundries to design the casting process for manufacturing of castings before castings are prepared or before equipment is constructed or improved. The basic objective of using computerized casting modeling and solidification simulation is to increase the quality of the casting manufactured, both in the existing produced casting and first ever castings made and to reduce cost expenses. The shop floor trials can be reduced effectively by casting solidification simulation and defect free castings can be assured. The casting simulation approaches are based on finite element method (FEM), finite difference method (FDM), finite volume method (FVM). In this paper an attempt has been made to use finite difference method (FDM) and finite volume method (FVM) for casting solidification simulation and optimization of casting gating system to assure maximal yield. Modeling and simulation of Flange is analyzed in this study. The material for the flange is ductile iron and produced using shell molding process. Ductile iron has wide range of mechanical properties suitable for production of automotive parts. The 3D model of flange and gating system is created using CATIA and it is simulated using Solid CAST and Auto CAST-X software’s. The simulation software results will predict the location and level of shrinkage. Optimization of gating system will improve casting yield. This will suggest the modifications needed in gating system.

To obtain the warm spin-ability of the thin-walled hemispherical part, the conventional spinning of aluminum alloy 2219 sheets with a thickness of 2mm is studied in this work. A spinning machine equipped with induction heating was set up, and a thermo-mechanical coupled spinning simulation of the AA2219 hemispherical part was developed. And the deformation temperature of about 250 ℃ can be realized for the AA2219 sheet. The effect of the deformation temperature on the spin-ability of the spun part has been studied by experiment and numerical simulation. The experimental results show that a stable and uniform temperature on the blank flange can be achieved via induction heating, and the developed numerical model is reliable for simulating the induction heating spinning process. Compared with the cold spinning, the warm spinning heated by induction coil causes the decrease of the flange anti-wrinkling and the increase of the thinning of the spun parts, but a less shape error in a single pass process.

Even a simple cold forming operation takes into account many technological parameters and has advantages comparing to the hot forming technology (e.g. hardening for massive parts). The right choice of technological parameters can result to high economic benefits in a mass production. The main restriction of the well-known methods of cold forming of “rod with flange” parts (e.g. bolts and screws) production is the possibility of the buckling of workpiece in a longitudinal direction if the upsetting length-to-the diameter ratio (L/D) of the deformed length is either equal or more than 2.5. To increase the efficiency of a technological operation it is suggested to apply spring-loaded lower die. To investigate the influence of the friction forces, different values of the friction factors were assigned on the contact surfaces. The process was simulated using FEM-code QFORM. The head height of the deformed workpiece was taken as a merit of accuracy during the simulation. In addition, the head shape and metal flow due to friction changes were investigated, as well. The results shown in this paper were confirmed by experiments, carried out on aluminium wrought alloy AA1013 using different lubricants.

Publisher Summary The piping isometric is an important drawing that serves several purposes. It is the primary source for material take-off of each pipe configuration in a facility. Material take-off is the process by which each individual component that makes up a pipe configuration is tabulated for purchase or procurement. This means that all piping components (elbows, flanges, nuts, bolts, washers, gaskets, etc.) must be counted so that purchases of those items can be made. The tabulated results are referred to as the bill of materials. Isometrics also serve as fabrication drawings. Once drawn and properly dimensioned, isometrics are provided to fabricators who build each piping configuration. Fabricators will use the completed isometrics to build shop spools. Shop spools are detailed specifically for pipe welders and fitters with precise cut-lengths and weld symbols. After configurations are fabricated, X-rayed, painted, and shipped to the construction site, isometric drawings serve as an aid to the construction and erection of the facility by providing workers with the locations of tie-ins, connections, and routings.

The global buckling behaviour of hot-rolled stainless steel channel section beam–columns under combined compression and minor-axis bending moment has been studied based on testing and numerical modelling and reported in this paper. A testing programme was conducted on ten hot-rolled austenitic stainless steel channel section beam–columns, with five buckling towards webs and the other five buckling towards flange tips. This was followed by a numerical modelling programme, in which finite element models were firstly developed and validated against the test results and then used to perform parametric studies to generate further numerical data over a wide range of cross-section dimensions, member effective lengths and loading combinations. The test and numerical results were adopted to assess the current design interaction curves given in the European code and American guide, both of which were found to result in inaccurate and scattered failure load predictions. The inaccuracy of the codified design interaction curves stems from the inaccurate end points (i.e. the member resistances under pure compression and pure bending) and the inappropriate shape. To address these shortcomings, a new design interaction curve was developed firstly through the adoption of more accurate end points and secondly through the derivation of a more proper shape. The proposed design interaction curve was shown to yield accurate and consistent failure load predictions for hot-rolled stainless steel channel section beam–columns. The reliability of the new proposal was also confirmed by means of statistical analyses. The authors thank Stainless Structurals Asia for sponsoring hot- rolled stainless steel channel sections.

Highway bridge superstructures may be built using only precast concrete elements, such as deck bulb tees (DBTs). Formerly flange connections between those members have been made with welde...

This paper investigates computationally the fire performance of a plug steel-concrete composite flooring system, the partially encased ultra-shallow floor beams (USFB). The investigation of the behaviour of USFBs exposed to standard and natural fires is crucial in determining their fire resistance and evaluating their overall performance in contemporary construction. Although the product providers usually indicate the fire resistance of USFBs based on EΝ1994-1-2 procedures, the response to elevated temperature effects remains yet neither well documented nor clearly understood. This analysis involves two different beams of 5 m and 8 m span. Results show that the unprotected beams experience severe temperature gradients while exposed to standard fire, as the lower flange still remains unprotected in contrast to the upper steel parts of the cross-section which are encased in concrete. Their fire resistance rating is found approximately at 40 min. Moreover, different thermal gradients are developed when the USFBs are exposed to natural fires (slow and fast burning). When the lower flange is protected with intumescent coatings, the USFBs have shown increased fire resistance and they can survive a full duration of a natural fire under realistic utilization ratios. From the parametric analyses, the optimized thicknesses for the required intumescent coating were obtained to achieve 60, 90, and 120 min of fire resistance and for surviving of natural fires exposures.

The maintenance strategies of the worn wheels have an important impact on maintenance cost of railway. LM worn wheels of heavy haul wagons are often re-profiled to their original standard form, and...

Wear is the main mechanism that reduces the lifetime of forging dies used in closed die forging. A newly proposed approach to decrease die wear is the concept of protective sheet metal forging die covers, where an inexpensive and easy-to-exchange sheet metal die cover is used to protect forging dies. After this concept has been fundamentally validated by previous studies, the presented work aims to further evaluate the protective effects of this concept regarding wear reduction. First, an application-oriented experiment of the die cover concept on forging dies for producing square flange was conducted. On both the forging dies with and without die covers 100 forging strokes were carried out. The wear depths of both forging dies were then measured and compared. The results indicated that the forging die with die covers has up to 98% less wear than the forging die without die covers. The expected tool life of the forging die with die covers is therefore 600% longer. In addition, the die cover applied in the experiment achieved the service life of 100 forging cycles without being distorted, which reached the maximum service life of the die cover concept so far.

The present research investigates the effect of binder force in flanging of aluminum alloy sheets. FEM simulation of stretch flange forming is realized for zero, constant, and fixed binder forces. ...

The authors have developed the novel process for joining dissimilar metals, which uses gas metal arc welding and an auxiliary insert or element. In this process, the element or the flanged steel rivet that has a hollow center is inserted into the pre-hole prepared in an aluminum alloy sheet for the first step. Second, the hollow center is filled with steel weld metal by arc spot welding to join the element and a steel sheet at the fixing point, and thereby the element and the steel sheet are welded strongly enough to fasten the aluminum alloy sheet between the flange of the element and the steel sheet. This new joining process is called element arc spot welding (EASW). EASW has such advantages that it can easily be applied to a dissimilar metal joint with ultra-high-strength steel; it does not need to pinch the joining metals from the upper and lower sides of the joint with a clamping tool; and the resultant shear and peel strengths of the joint are equal to or greater than those by other dissimilar metal joining processes. The prototype robot system for automating the EASW process has also been developed. In this robot system, the position of the pre-hole in the aluminum alloy sheet is detected by an image sensor, and then the tool at the tip of the robot arm moves to the detected pre-hole position to insert the element correctly into the hole; in the next step, low-spatter arc welding is carried out to fasten the aluminum alloy sheet between the element and the steel sheet.

Panelized building construction are highly mechanized. Material handling and lifting equipment dominate construction sites and constitute the critical element in achieving productivity. In recent construction practice, panelized wood I-joist floor panels are normally lifted into place by mobile crane using flexible slings inserted through the predrilled holes on the I-joist web and sheathing panels above the I-joist top flange and then wrapped around the I-joists at the four corners. However, the pre-drilled holes on the web and sheathing may weaken the floor panels. Moreover, a range of techniques for lifting and handling mass timber panels have been developed. A typical rigging technique consists of a lifting ring and a steel plate with pre-drilled holes. By using several self-tapping screws, the panel was connected with the rigging device for lifting. However, since prefabricated I-joist floor panels are much lighter than mass timber panels and the I-joist flange is relatively narrow and thin, the rigging device for mass timber panels cannot be applied directly to I-joist floor panels, but a modified design can be developed for prefabricated I-joist floor panels. In the present study, a new rigging device was designed for prefabricated wood I-joist panels and their load capacity was evaluated by withdrawal tests. Several factors influencing the withdrawal capacity were investigated including screw types and quantities, flange width and materials, and OSB thickness.

One flange of a spring belonging to an actuator drive that worked under torsion has been fractured. It is placed next to the electric motors whose mission is to move the drive manually through a hexagonal key. The whole equipment is an extensor-retraction actuator consisting in two electric motors that run a gear. This gear pulls a chain moving a telescopic beam. It was confirmed that there was no signs of anomalous working previous to the fracture. Some roughness requirements were mandatory in the first wire of the spring as well as both spring flanges, thus two springs (used and new) were compared. Several tests were performed in order to determine the cause of the fracture such as a chemical and mechanical characterization of the material, a fractographic analysis of the fracture surface, and the determination of the spring treatment state using metallographic and microscopic techniques. Additional observations were carried out in the other flange in order to detect possible defects. It was verified that the material corresponds to a 300 maraging steel type IV in a solubilization and ageing heat treatment state. The fracture surface presented fractographic characteristics of a typical progressive fracture. It was concluded that although the steel type and treatment state is correct, the roughness of specific zones is not well finished and, may have generated a crack that have nucleated in a notch of the first wire of the spring inner side surface. The crack may be produced by a pinned particle or any other surface defect that afterwards may propagate by a fatigue mechanism.

A numerical investigation on the flexural behaviour of Lean Duplex Stainless Steel (LDSS), Hybrid Stainless Steel (HSS) and Duplex Stainless Steel (DSS) I-beams using the commercial finite element software, ABAQUS are presented in this paper based on cross-section slenderness i.e. flange and web critical sections. 3-point bending (3PB) and 4-point bending (4PB) specimens were chosen for the current numerical investigations. Based on the study, it has been observed that for both Class 1 flange-critical and web-critical sections, LDSS I-beams has a higher R (rotation capacity) as compared to HSS and DSS I-beams. Significant increase in Mu (ultimate bending strength) can be seen in case of HSS I-beams, as compared to DSS and LDSS I-beams. In general, EN 1993–1-4 is found to be reliable and applicable for LDSS, HSS and DSS I-beams. New DSM formulation for HSS I-beams has been proposed based on the full-range modified Direct Strength Method (DSM) formulation for carbon steel.

Cementitious coatings are widely used to protect steel structures from fire, yet there are concerns about its performance in earthquakes, where partial damage to the fire protection could potentially compromise the fire safety of steel structures. In this paper, results from a series of experiments are presented to quantify the damage in cementitious fire resistive coatings under cyclic loading. Steel plates of various sizes are first tested under cyclic loading, which exhibit greater damage than the specimens subjected to monotonic loading. A steel column is subjected to cyclic load along with another subjected to monotonic load are both coated with 20 mm thick cementitious fire resistive material and tested to investigate the damage patterns in a more realistic setup than steel plates. Tensile transverse cracks on the flange, vertical cracks along the flange tip, and interfacial debonding of the coatings are the main forms of coating damage, which appear with a lower story drift ratio compared to the monotonically loaded column specimen.

Laser brazing technique was employed to weld-braze 2 mm thick galvanized steel to 5083 aluminum alloy in flange joint configuration using 2 mm diameter solid AlSi12 (AA4047) filler wire. Experiments were performed at various wire feed rates (2.0–3.6 m/min) with constant laser power (3.5 kW), scan speed (2.5 m/min) and spot size (1.7 mm). The microstructural observation of the etched specimens under SEM showed cast structure at the brazed zone and a two-layered (planar and needle structured) interface towards the galvanized steel. HAZ was observed at the aluminum side. The selective Energy-dispersive X-ray spectroscopy (EDS) point analysis and X-ray diffraction technique were used to study the interface and the results confirmed that the planar and needle structures are comprised of ternary Alx-Fey-Siz and binary Alx-Fey intermetallic phases respectively. From hardness testing, both the base material, i.e., AA5083and galvanized steel are found to be harder than brazed zone. In case of nano-indentation testing, intermetallics have shown higher hardness values compared to base materials. The joint strength increased with increasing wire feed rate and recorded interfacial failure. Fatigue life of the laser brazed joints at lower stain amplitude is better with increasing wire feed rate and are in close range to the aluminum base material (AA5083) value. Fatigue tested specimens recorded brazed zone failure and revealed flow lines, intergranular cracking and typical fatigue striations.

The current work presents a failure analysis study conducted on a fractured mechanical fastener made of Cu 12Mn alloy. The fastener was obtained from a flange of a large-diameter steel tube operating in a sea submersible platform. Macrofractography and Microfractography, Standard Optical Metallography, Scanning Electron Microscopy (SEM), X-ray Fluorescence (XRF) and Energy-Dispersive X-ray Spectroscopy techniques as well as Numerical Modeling were employed to assist the investigation. Fracture was eventually attributed to the synergistic action of fatigue and selective leaching (corrosion-assisted fatigue).

This paper presents an experimental and a FE analysis of the compressive behavior of slender section columns with and without stiffeners. A series of tests was performed on specimens with different overall heights and different number of stiffeners. A nonlinear three-dimensional FE model was developed using ANSYS program. The efficiency of the nonlinear FE model was verified and a parametric analysis was performed considering variation of number of stiffeners, values of web depth-to-thickness ratio, flange-to-thickness ratio, and slenderness ratio. The load carrying capacity of steel columns with large web-to-thickness ratio is noticeably enhanced up to 34% by increasing number of web stiffeners. Initial imperfection during fabrication should be well controlled and should be carefully considered in the FE modelling. Post local buckling strength of the sections is more sensitive to web width–thickness ratio than flange width–thickness ratio. Keywords: Slender sections, Local buckling, Stiffened I-column, Web stiffener, FE simulation, ANSYS

Research on T-configuration aluminum constructions effectively decreases fuel consumption, increases strength, and develops aerial structures. In this research, the effects of friction stir welding (FSW) tool offset (TO) on Al–Mg–Si alloy mixing and bonding in T-configurations is studied. The process is simulated by the computational fluid dynamic (CFD) technique to better understand the material mixing flow and the bonding between the skin and flange during FSW. According to the results, the best material flow can be only achieved at an appropriate TO. The appropriate TO generates enough material to fill the joint line and results in formation of the highest participation of the flange in the stir zone (SZ) area. The results show that, in the T-configuration, FSW joints provide raw materials from the retreating side (RS) of the flange that play a primary role in producing a sound mixing flow. The selected parameters were related to the geometric limitations of the raw sheets considered in this study. The failure point of all tensile samples was located on the flange. Surface tunneling is the primary defect in these joints, which is produced at high TOs. Among the analyzed cases, the most robust joint was made at +0.2 mm TO on the advancing side (AS), resulting in more than 60% strength of the base aluminum alloy being retained.

This paper develops a new type of shear connection for steel-concrete composite bridges using Ultra-High Performance Concrete (UHPC) as the connection grout. The UHPC-grout strip shear connection is fabricated by preforming a roughened slot in the concrete deck slab, welding an embossed steel rib longitudinally to the upper flange of the steel girder, and casting the strip void between the slot and the steel rib with UHPC grout. The structural performance of the new connection was validated by two sets of experimental tests, including push-out testing of shear connectors and static and fatigue testing of composite beams. The results of push-out testing indicate that the UHPC-grout strip shear connection exhibits a significant improvement of ductility, ultimate capacity, and fatigue performance. The interface shear strength of the UHPC-grout strip connection is beyond 15 MPa, which is about three times that of the strip connection using traditional cementitious grouts. The ultimate capacity of the connection is dominated by the interface failure between the embossed steel and the UHPC grout. The results of composite-beam testing indicate that full composite action is developed between the precast decks and the steel beams, and the composite action remained intact after testing for two million load cycles. Finally, the trail design of a prototype bridge shows that this new connection has the potential to meet the requirements for horizontal shear.

This work aims to enhance the energy-dissipation capacity of classical rectangular T-stubs by proposing an hourglass shape for the T-stub flange according to the approach usually adopted for added damping and stiffness (ADAS) devices. A new type of axial damper is developed. First, a mechanical model of the device is set up and a finite-element model is carried out in ABAQUS code. The accuracy of both models is verified through comparison with experimental results. Next, on the basis of cyclic tests, the improvement of the energy-dissipation capacity of classical T-stubs provided by the proposed approach is quantified, and the low-cycle fatigue curves are determined with reference to the case of both T-stubs on rigid support and of coupled T-stubs. The results of the work also represent a useful tool for designing a dissipative double split tee connection.

Forged products are one of the most products which represent heavy industry in the countries. Forging die design is a kind of art used to produce accurate and net-shape products in this field. As its related only to heavy industries, it’s not available in many countries and many of students have not the background about this kind of die design. This paper discusses a proposed CAD software have 2 kind of applications. The first is industrial application as used to design a closed forging die for six products "Shaft, Flange, Flange with neck, hook, connecting rod, and crank shaft". The second application is to support education process, as the CAD system build in steps to show the students the steps of closed forging design process. The system build using Visual basic for application "VBA" add-in to SolidWorks Programming. The system supposed to be used in Faculty of engineering campus or similar and also to be used in Design department in Forging companies.

Stainless steel offers a range of benefits over conventional carbon steel in structural applications. This paper presents the detailed numerical modelling of shear response of cold-formed stainless steel hollow flange sections using finite element software package, Abaqus. The effect of geometric parameters such as section height and section thickness, and the influence of different steel grades were investigated following the validation of finite element models. From numerical results, the formation of diagonal tension fields can be clearly observed in the webs of rectangular hollow flange sections while more even distribution of the stresses in the webs is seen in triangular hollow flange sections. Further, a plastic hinge type mechanism is formed in triangular flanges at the post-failure region. The evaluation of Eurocode 3 and the direct strength method shear design provisions for stainless steel hollow flange beams is found to be significantly conservative. Therefore, modified provisions were proposed and the comparison of those with finite element results confirmed the accurate and consistent shear resistance predictions over the codified provisions.

Because of the low ductility of Ti–6Al–4V alloy at the temperatures between room temperature and 600 °C, fracture easily occurs during press forming. Hence, a method of press forming of Ti–6Al–4V alloy sheets at 300 °C was developed. In this method, the punch motion and blank holding force were applied separately to prevent fracture at the punch radius until the maximum punch load was reached, and the deep drawing process was demonstrated from the maximum punch load until finish forming to prevent the fracture at end of the flange. In addition, by applying the developed method, we were able to prevent the decrease in wall thickness at the punch shoulder, compared with that in press forming. As a result, warm press forming of Ti–6Al–4V alloy sheets at 300 °C was achieved without fracture of the formed cup or local decrease in the wall thickness by applying the developed method.

Every year the repair costs for pipe replacement are lost due to corrosion in gas and oil pipelines increasing this can also affect the LPO (Loss Production Opportunity) due to production stoppages, due to the replacement and repair process. Currently investigating the cause of the damage is an alternative prevention to take preventive measures for the occurrence of the same condition, in addition to reducing costs and reducing consumption of new pipes for replacement. This paper examines the metallurgical and stress aspects of the material failure on the Flange Spool T Arm in the SBG-17 well head (upstream) and the Flange Spool Header Manifold (downstream), where the Spool Header Manifold was a combined flow of the SBG-17 and SBG-16 well heads. In the same condition, there was no material failure on the Flange Spool T Arm in the SBG-16 well head. The simulation results show the maximum calculated pipe stress, less than the allowable stress, the lines conform to ASME B32.3 code for the operating temperature of 60oC and 570 Psig respectively. Suspected of corrosion products at the damaged area of sample were iron oxides (FeOOH and/or Fe2O3), iron carbonates (siderite-FeCO3) and iron sulfides (FeS). The form of damage on the weldment flange spool well head only occur on the weld area, due to turbulence the layer of siderite is swiped away leaving local breakdown of corrosion products that exposed the metal to environment then it acts as anodic site where dissolution reaction occurs. The form of damage on the weldment flange spool header not only occur on the weld area, but also occurs at the base metal area. SEM observation on sample revealed the cubic shapes of corrosion products, which were typical for siderite (FeCO3) as the product of CO2 corrosion. This kind of corrosion commonly occur in mature oil wells, combination of high water cut and partial pressure of CO2.

The book in question pertains to some selected issues regarding composite steel and concrete structural members. It contains information on the state-of-the-art designs and constructional technologies in the field of composite structures in Slovakia and abroad. Particular attention is drawn to deck bridges with encased filler-beams to show some new possibilities and challenges in such structures. This type of construction is well-suited to bridge obstacles over short spans, and it is currently exploited to bridge sluices, culverts, rivers, roads, and other obstacles as wide as up to 18 m. Still, it is only the I-sections that are encased as the rigid reinforcement in most cases. Another purpose of this work was to bring a new progressive modified and experimentally verified shape of steel section into the civil engineering world. The steel box section provides an improved method of composite action/shear connection, ensured by the holes made both in the top flange and the webs of the steel beam. Another advantage of the steel box section rests in its exceptional flexural stiffness, which can guarantee that the beam will bear the dead weight of the fresh concrete in the construction process if necessary.

A 234 steel flange ASTM is widely used in oil and gas. A damage flange from a unit of submersible pump operated at an offshore platform. The leakage was occurred at the flange connection at submerged part of the vertical pump. The external protection of the section was external coating. The leakage had occurred twice at the same vertical pump. The present investigation aims to analyze the main cause of the failure by conducting a standard failure analysis test including chemical composition test, visual examination, microstructural examination by optical microscope and scanning electron microscope (SEM) equipped with energy-dispersive spectroscopy (EDS), X-ray diffraction and Brinell hardness measurement. The results of this investigation on the failed flange showed that the microstructure of the flange material is found to be ferrite-pearlite with banded structure on the pearlite. This banded structure influences the corrosion properties of the material. It is found that pearlite banded structure increase the corrosion rate of carbon steel. However, the damage mechanism could be due to Galvanic Corrosion and Crevice Corrosion. These two mechanism are possible to the flange joint between the bowl and column. The bowl is known as Nickel-Aluminum-Bronze (NAB) while the column is carbon steel (CS).

Authors would like to thank Işik University, Ataturk University, ATASAM, OPAM, and the Ministry of Development for the funding and support (2011K120230). The purpose of this study is expressing advances in design stages for in flange optical field derotator system for 4 meters DAG Telescope. In-Flange Derotator KORAY (K-mirror OpticalRelAY) is designed, analysed and manufactured to meet the specifications of DAG telescope. DAG telescope, situated at Erzurum/Karakaya summit at 3150m altitude, is the first Turkish optical telescope with VIS(Visible) and IR (Infrared) observation capability. DAG, designed by Turkish engineers at FMV Isik University, is also the largest telescope (4m diameter) in Turkey and in European continent. Being one of the 2023 vision projects; the first light of DAG is expected to take place in 2021. This purpose brings some real-life challenges such as design limitations, material selection and electronic integration. Publisher's Version WOS:000769070400067

The paper addresses the prototypical development and implementation of an innovative and functionally integrated gear stage for next-generation electric vehicles, produced by using Laser Beam Melting (LBM) and Fused Deposition Modeling (FDM). Two new design targets are addressed by our approach: Oil-free operation is achieved by innovative coating of gear teeth which enables almost maintenance-free operation. Furthermore, a higher damping of sound transmission from tooth mesh to bearings is implemented by an optimal wheel body geometry that is realized by a combination of printable carbon-containing polymers (flange) and steel (gear rim). The innovative approach is to extend components by areas that cannot be produced by milling and casting, e.g. complex structures, contour-following fluid-carrying cooling elements by means of LBM, thus creating a significant benefit compared to state-of-the-art gearboxes. Function integration made possible by additive manufacturing results in a very high component complexity. It is combined with gear grinding and final ta-C coatings ensuring maximum efficiency in dry operation, to achieve economically viable production processes. The increase in tooth mesh efficiency is achieved by optimization approaches in the design to minimize heat losses while at the same time maintaining highest possible strength and lowest noise emission.