scholarly journals RANCANG BANGUN RASIO GEAR TERHADAP KECEPATAN PENGEROLAN PIPA

Infotekmesin ◽  
2018 ◽  
Vol 9 (01) ◽  
pp. 47-52
Author(s):  
Agus Suprihadi ◽  
Amin Nur Akhmadi ◽  
M. Taufik Qurohman

The basic principle of metal formation is a process that is done by giving shape changes on the workpiece. This shape change can be done by providing an outer force resulting in plastic deformation. The application of this metal formation can be seen in some examples such as rolling, bending, forging, extruding, wire drawing, deep drawing, and so on. In the process of formation of this metal is also used tooling (bending) whose function gives style to the workpiece, and direct the change of shape. Knowing the speed of the power forwarding system on the pipe roller machine starting from the power source until power is used as the work cycle, and to know the type of belt, the length of the belt used on the pipe roll machine. From this research can be concluded that: (1) In bending the thickness of 4 mm pipe the required power is 582.4 N with power of 0.4 hp then the motor required 1 hp, the diameter of the pulley used is 2 inch for motoran and 8 inch for the pivot reducer, belt used type B with length 44 inch, (2) To reach the rotation of ± 2 rpm ie pulley diameter used with the ratio of pulley ratio is 1: 4, the reducer is used with the value I = 60 and sprocket ratio 1: 3.

2018 ◽  
Vol 14 (1) ◽  
pp. 72
Author(s):  
Sir Anderson

The basic principle of metal formation is to change shape by giving an external force so that plastic deformation occurs. One example of this formation is wire drawing. The important parameter in wire drawing is the drawing force, which is the force needed to deform the wire to produce the desired reduction. The measurement of withdrawal force is carried out through a wire drawing test equipped with a dynamometer, which consists of load cell and strain gauge. From this test, the withdrawal force can be measured as an electrical quantity that can be read using a multitester or computer. For wire drawing testing dynamometers are designed and made as measuring sensors for withdrawal forces on a laboratory scale. From the results of testing with a dynamometer the average wire drawing force for copper reduction I was 72.88 kgf, copper reduction II was 95.88 kgf and brass was 126.50 kgf. The price of this test is greater than the theoretical price


2015 ◽  
Vol 1114 ◽  
pp. 143-148
Author(s):  
Nicolae Serban ◽  
Doina Răducanu ◽  
Vasile Danut Cojocaru ◽  
Nicolae Ghiban

Severe plastic deformation (SPD) has received enormous interest over the last two decades as a method capable of producing fully dense and bulk ultra-fine grained (UFG) and nanocrystalline (NC) materials. Significant grain refinement obtained by SPD leads to improvement of mechanical, microstructural and physical properties. Compared to classical deformation processes, the big advantage of SPD manufacturing techniques, represented in particular by equal channel angular pressing (ECAP) is the lack of shape-change deformation and the consequent possibility to impart extremely large strain. In ECAP processing, the workpiece is pressed through a die in which two channels of equal cross-section intersect at an angle of ϕ and an additional angle of ψ define the arc of curvature at the outer point of intersection of the two channels. As a result of pressing, the sample theoretically deforms by simple shear and retains the same cross-sectional area to allow repeated pressings for several cycles. A commercial AlMgSi alloy was investigated in our study. The specimens were processed at room temperature for multiple passes, using three different ECAP dies. All samples (ECAP processed and as-received) were subjected to metallographic analysis and mechanical testing. Several correlations between the main processing parameters and the resulting microstructural aspect and mechanical features for the processed material were established. It was shown that severe plastic deformation by means of ECAP processing can be used in aluminum alloys microstructural design as an advanced tool for grain refinement in order to attain the desired microstructure and mechanical properties.


Development ◽  
1994 ◽  
Vol 120 (4) ◽  
pp. 853-859 ◽  
Author(s):  
M. Leptin ◽  
S. Roth

The mesoderm in Drosophila invaginates by a series of characteristic cell shape changes. Mosaics of wild-type cells in an environment of mutant cells incapable of making mesodermal invaginations show that this morphogenetic behaviour does not require interactions between large numbers of cells but that small patches of cells can invaginate independent of their neighbours' behaviour. While the initiation of cell shape change is locally autonomous, the shapes the cells assume are partly determined by the individual cell's environment. Cytoplasmic transplantation experiments show that areas of cells expressing mesodermal genes ectopically at any position in the egg form an invagination. We propose that ventral furrow formation is the consequence of all prospective mesodermal cells independently following their developmental program. Gene expression at the border of the mesoderm is induced by the apposition of mesodermal and non-mesodermal cells.


2018 ◽  
Vol 941 ◽  
pp. 1914-1919
Author(s):  
Florent Moisy ◽  
Antoine Gueydan ◽  
Xavier Sauvage ◽  
Clément Keller ◽  
Alain Guillet ◽  
...  

Architectured copper clad aluminium composites processed by a restacking drawing method at room temperature are reported in this work. Wires were drawn to severe plastic strain without any intermediate annealing. Three different diameters were studied in order to examine the influence of a different plastic deformation level on the structure of the different wires. Thanks to image processing it has been shown that independently of the plastic deformation, inserted fibers remain continuous and are homogeneous in size and shape. Furthermore, XRD and TEM characterizations confirm that there is no significant intermetallic growth during the deformation. Thus, the improvement and/or degradation of the functional properties of the wires can be well controlled by performing an appropriate post-processing annealing treatment. Keywords: Cu/Al composite, architectured wire, drawing, microscopy, image processing


2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Wei Kong ◽  
Bo Liu ◽  
Bo Ye ◽  
Zhongping Yu ◽  
Hua Wang ◽  
...  

Titanium dioxide (TiO2) nanocrystals of different shape were successfully synthesized in a new microemulsion system through a solvothermal process. The TiO2nanocrystals were prepared from the reaction of tetrabutyl titanate (TBT),H2O, and oleic acid (OA), which were used as solvent and surfactant at 300∘Cand 240∘Cin a stainless steel autoclave. The sphere, polygon, and rhombus-shaped nanocrystals have been prepared at 300∘Cand the dot- and- rod shaped nanocrystals have been synthesized at 240∘C. The effect of the reaction time on the shape and size of TiO2nanocrystals in this method was studied in the present paper. The size distribution of TiO2nanocrystals prepared at 300∘Cfor different hours is also studied. In addition, an attempt to describe the mechanism of shape change of TiO2nanocrystals was presented in this paper.


1999 ◽  
Vol 73 (2) ◽  
pp. 355-371 ◽  
Author(s):  
Mark Webster ◽  
Nigel C. Hughes

Morphometric analyses of silicified and nonsilicified (preserved in shale) specimens of the olenelloid trilobites Olenellus (Olenellus) gilberti Meek (in White, 1874) and Nephrolenellus geniculatus Palmer, 1998, from the Lower Cambrian C-Shale Member of the Pioche Formation show that even well-preserved specimens in shales have undergone significant changes in lateral as well as vertical dimensions as a result of compaction. Analyses of cephalic landmarks show that in both species compaction causes posteriordirected collapse of the anterior lobe of the glabella, adaxial deformation of the ocular lobes, and abaxial and anterior splaying of genal regions. These shape changes are explicable in terms of observed exoskeletal fracture patterns. Landmarks show an increase in scatter around their ontogenetic trajectories that is generally proportional to the degree of lateral shift each landmark has undergone. Interspecific differences in compactional response may depend on the relative convexity of the cephalon. Olenellus (Olenellus) gilberti is a low-convexity species and shows marked lateral shape change, particularly in the genal region. Nephrolenellus geniculatus is more convex and shows less severe lateral shape change. Landmarks of both species exhibit an average trebling of the degree of scatter around their average ontogenetic trajectories in compacted samples. Because even well-preserved specimens in shales differ in shape from their precompactional appearance, results of morphometric studies utilizing metric distances between landmarks in trilobites where compaction can be detected must be interpreted with caution.


Development ◽  
1995 ◽  
Vol 121 (3) ◽  
pp. 903-914 ◽  
Author(s):  
N. Harden ◽  
H.Y. Loh ◽  
W. Chia ◽  
L. Lim

The Rho subfamily of Ras-related small GTP-binding proteins is involved in regulation of the cytoskeleton. The cytoskeletal changes induced by two members of this subfamily, Rho and Rac, in response to growth factor stimulation, have dramatic effects on cell morphology. We are interested in using Drosophila as a system for studying how such effects participate in development. We have identified two Drosophila genes, DRacA and DRacB, encoding proteins with homology to mammalian Rac1 and Rac2. We have made transgenic flies bearing dominant inhibitory (N17DRacA), and wild-type versions of the DRacA cDNA under control of an Hsp70 promoter. Expression of the N17DRacA transgene during embryonic development causes a high frequency of defects in dorsal closure which are due to disruption of cell shape changes in the lateral epidermis. Embryonic expression of N17DRacA also affects germband retraction and head involution. The epidermal cell shape defects caused by expression of N17DRacA are accompanied by disruption of a localized accumulation of actin and myosin thought to be driving epidermal cell shape change. Thus the Rho subfamily may be generating localized changes in the cytoskeleton during Drosophila development in a similar fashion to that seen in mammalian and yeast cells. The Rho subfamily is likely to be participating in a wide range of developmental processes in Drosophila through its regulation of the cytoskeleton.


1989 ◽  
Vol 92 (3) ◽  
pp. 473-485
Author(s):  
I. Kuter ◽  
B. Johnson-Wint ◽  
N. Beaupre ◽  
J. Gross

We have investigated the relationship between collagenase production, cell shape and stimulatory factors in cell culture. In a homogeneous culture of primary rabbit corneal stromal cells, shape change induced by a variety of agents was not effective in stimulating collagenase secretion. Only in the presence of a biologically active cytokine or phorbol myristate acetate was a correlation seen between changes in cell shape (induced by a second agent) and collagenase secretion by these primary cells. Cell shape changes were not, however, necessary for collagenase secretion, since certain concentrations of endotoxin or lactalbumin hydrolysate effected secretion of the enzyme in the absence of morphological changes. With passaged cells or mixed cell cultures, where cell shape change did correlate with collagenase secretion without the addition of an exogenous agent, the production of an effective cytokine (autocrine or paracrine) was demonstrated. Thus cell shape change seems to be neither universally necessary nor sufficient for the stimulation of collagenase secretion. It is proposed that the function of cytokines may be more immediately related to gene expression in this system than is change in the shape of the cell. The hypothesis is presented that cell shape changes may render the target cells receptive to cytokines, perhaps by replacing the need for a natural cytokine cofactor. It is also demonstrated here that the use of passaged cells, mixed cell cultures containing endogenous cytokine-secreting cells or tissue culture additives can profoundly affect the interpretation of the effect of various agents on collagenase secretion, and may lead to observations that are not directly relevant to cell function in vivo.


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