scholarly journals Improvement of prt-9 constructive system on the basis of frame elements strength balance

2020 ◽  
Vol 100 (4) ◽  
pp. 40-45
Author(s):  
Taras Dovbush ◽  
Nadia Khomyk ◽  
Hanna Tson ◽  
Anatoliy Dovbush
Keyword(s):  
Cross Section ◽  
Rectangular Cross Section ◽  
Organic Fertilizer ◽  
Experimental Investigations ◽  
Thin Walled Tube ◽  
Thin Walled ◽  
Strength Uniformity ◽  
Shaped Cross Section ◽  
Main Frame

Analytical and experimental investigations of the most loaded elements of the base frame of PRT-9 solid organic fertilizer spreader are carried out in this paper. The residual operation life of the central beam of the paired Z-shaped profile, as well as the lateral spars of the Z-shaped cross section are determined. According to the results of studies, it was found that the residual operation life of these system elements differ significantly. In order to achieve strength uniformity of the main frame elements, it is decided to weaken the central beam by replacing the paired Z-shaped profile with a thin-walled tube of rectangular cross-section and strengthen the lateral spars by replacing Z-shaped profile with a channel profile with the same height.

Thin-Walled Beams: the Case of the Rectangular Cross-Section

2004 ◽  
Vol 76 (1) ◽  
pp. 45-66 ◽  
Author(s):  
Lorenzo Freddi ◽  
Antonino Morassi ◽  
Roberto Paroni
Keyword(s):  
Cross Section ◽  
Rectangular Cross Section ◽  
Thin Walled

Experimental and Numerical Study of the Energy Absorbed with Various Thickness of Thin Rectangular and Square Sections

2012 ◽  
Vol 229-231 ◽  
pp. 1120-1124
Author(s):  
Sajjad Dehghanpour ◽  
Sobhan Dehghanpour
Keyword(s):  
Numerical Analysis ◽  
Energy Absorption ◽  
Cross Section ◽  
Numerical Study ◽  
Rectangular Cross Section ◽  
Lateral Loading ◽  
Thin Walled

Impact is one of very important subjects which always have been considered in mechanical science. Nature of impact is such that which makes its control a hard task. Therefore it is required to present the transfer of impact to other vulnerable part of a structure, when it is necessary, one of the best method of absorbing energy of impact , is by using Thin-walled tubes these tubes collapses under impact and with absorption of energy, it prevents the damage to other parts. Purpose of recent study is to survey the deformation and energy absorption of tubes with different type of cross section (rectangular or square) and with similar volumes, height, mean cross section, and material under loading. Lateral loading of tubes are quasi-static type and beside as numerical analysis, also experimental experiences has been performed to evaluate the accuracy of the results. Results from the surveys is indicates that in a same conditions which mentioned above, samples with square cross section ,absorb more energy compare to rectangular cross section, and also by increscent in thickness, energy absorption would be more.

Flexural Vibrations of a Thin-Walled Cylinder of Rectangular Cross Section

1958 ◽  
Vol 9 (4) ◽  
pp. 331-345
Author(s):  
E. H. Mansfield
Keyword(s):  
Cross Section ◽  
Stress Function ◽  
Flexural Rigidity ◽  
Rectangular Cross Section ◽  
Shear Lag ◽  
Transverse Vibrations ◽  
Thin Walled ◽  
Flexural Vibrations ◽  
Walled Cylinder ◽  
Natural Transverse

SummaryThe natural transverse vibrations of a long cylindrical box of doubly symmetrical rectangular cross section are considered. Explicit stress-function solutions are obtained for the webs and the top and bottom surfaces so that the effects of shear lag and shear deflection are inherently included. The results are expressed simply in terms of an effective flexural rigidity, which may be determined with the aid of a number of graphs.

scholarly journals Influence of the Geometrical Cross-Section Design on the Dynamic Cyclic Fatigue Resistance of NiTi Endodontic Rotary Files—An In Vitro Study

2021 ◽  
Vol 10 (20) ◽  
pp. 4713
Author(s):  
Vicente Faus-Llácer ◽  
Nirmine Hamoud-Kharrat ◽  
María Teresa Marhuenda Ramos ◽  
Ignacio Faus-Matoses ◽  
Álvaro Zubizarreta-Macho ◽  
...  
Keyword(s):  
Cross Section ◽  
Fatigue Resistance ◽  
Niti Alloy ◽  
Rectangular Cross Section ◽  
Study Groups ◽  
Cyclic Fatigue ◽  
Triangular Cross Section ◽  
Geometrical Cross Section ◽  
Section Design ◽  
Shaped Cross Section

The aim of this study was to analyze and compare the influence of the geometrical cross-section design on the dynamic cyclic fatigue resistance of NiTi endodontic rotary files. Materials and Methods: Forty sterile endodontic rotary files were selected and distributed into the following study groups: A: 25.06 double S-shaped cross-section NiTi alloy endodontic rotary files (Mtwo) (n = 10); B: 20.04 rectangular cross-section NiTi alloy endodontic rotary files (T Pro E1) (n = 10); C: 25.04 convex triangular cross-section NiTi alloy endodontic rotary files (T Pro E2) (n = 10); and D: 25.06 triangular cross-section NiTi alloy endodontic rotary files (T Pro E4) (n = 10). A cyclic fatigue device was used to conduct the static cyclic fatigue tests with stainless steel artificial root canal systems with 200 µm and 250 µm apical diameter, 60° curvature angle, 3 mm radius of curvature, 20 mm length, and 4% and 8% taper. The results were analyzed using the ANOVA test and Weibull statistical analysis. Results: All the pairwise comparisons presented statistically significant differences between the time to failure and number of cycles to failure for the cross-section design study groups (p < 0.001). Conclusions: the double S-shaped cross-section of Mtwo NiTi endodontic files shows higher cyclic fatigue resistance than the rectangular cross-section of T Pro E1 NiTi endodontic files, the convex triangular cross-section of T Pro E2 NiTi endodontic files, and the triangular cross-section of T Pro E4 NiTi endodontic files.

Torsional Creep Buckling of Thin-Walled Open Tubes With a Cross Section Having an Axis of Symmetry

1962 ◽  
Vol 29 (1) ◽  
pp. 99-107
Author(s):  
George Lianis
Keyword(s):  
Cross Section ◽  
Closed Form Solution ◽  
Critical Time ◽  
Small Deformation ◽  
Form Solution ◽  
Creep Buckling ◽  
Thin Walled Tube ◽  
Axis Of Symmetry ◽  
Thin Walled ◽  
Stress Patterns

The variational theorem by Sanders, McComb, and Schlechte [1] is applied to find the critical collapse time of an open thin-walled tube with a cross section having an axis of symmetry subjected to torsional creep buckling. Large deformation strains are considered. It is shown that small deformation strains yield inaccurate results in predicting the critical time. A simplified stress distribution is introduced which gives a closed-form solution. More accurate stress patterns present considerable difficulties and a tedious numerical integration is needed. In examining most cases, however, the simplified stress configuration predicts the critical time very accurately.

Part II. The Flattening of Monocoque Cylinders

1938 ◽  
Vol 42 (328) ◽  
pp. 302-319
Keyword(s):  
Variational Method ◽  
Potential Energy ◽  
Cross Section ◽  
Radial Displacement ◽  
Bending Moment ◽  
Experimental Investigations ◽  
Pure Bending ◽  
Centre Line ◽  
Thin Walled ◽  
The Cross

It is known from both theoretical and experimental investigations that St. Venant's assumption on the constancy of the shape of the cross section of girders in pure bending does not hold true in case of thin-walled sections. The greater flexibility than calculated according to ordinary bending theory of initially curved tubes, as experimentally found by Professor Bantlin, was perfectly explained by Professor von Kármán in 1911 on the assumption of a flattening of the section.In 1927 Brazier with the aid of the variational method determined exactly that the shape of an originally circular thin-walled bent cylinder corresponding to the least potential energy is quasi elliptical and that the cross section of the cylinder, therefore, must flatten, even if the centre line of the cylinder was originally straight. In consequence of the flattening St. Venant's linear law for the curvature loses its validity and the curvature increases more rapidly than the bending moment. For a certain value of the curvature the bending moment is a maximum, and after this value was reached the curvature increases even if the applied moment remains unchanged or decreases, fulfilling thereby the criterion of instability. This instability occurs when the rate of flattening, i.e., the maximum radial displacement of any point of the circumference of the tube divided by the original radius of the tube, will equal 2/9.

Exploring Liquid Impact Forming Technology of the Thin-Walled Tubes

2014 ◽  
Vol 633-634 ◽  
pp. 841-844 ◽  
Author(s):  
Cheng Ming Huang ◽  
Jian Wei Liu ◽  
Yin Zhong Zhong ◽  
Min Jian Wu ◽  
Kai Ming Wang ◽  
...  
Keyword(s):  
Rectangular Cross Section ◽  
Tube Hydroforming ◽  
304 Stainless Steel ◽  
Steel Tubes ◽  
Forming Technology ◽  
Liquid Impact ◽  
Thin Walled Tube ◽  
Forming Efficiency ◽  
Thin Walled ◽  
Forming Methods

In order to realize the objective of lightweight manufacturing, the forming methods of thin-walled tubes are studied in this paper. Liquid impact forming, a compound forming technique of thin-walled tube using stamping and hydroforming processes, is presented in order to reduce the forming difficulty and increase the forming efficiency. A simple experimental tooling, including stamping device and tube hydroforming apparatus is developed. Forming experiments of stamping and liquid impact forming processes in rectangular cross-section dies are performed for 304 stainless steel tubes. The results of experiments show that the liquid impact forming technology is feasible, and it will be widely applied in the future.

scholarly journals Torsion of a thin-walled structure of a waveguide with rectangular cross-section

2021 ◽  
Vol 1155 (1) ◽  
pp. 012017
Author(s):  
I V Kudryavtsev ◽  
M V Brungardt ◽  
E A Goncharova ◽  
O A Li ◽  
S I Troshin
Keyword(s):  
Cross Section ◽  
Rectangular Cross Section ◽  
Thin Walled

scholarly journals High-Throughput, Label-Free Isolation of White Blood Cells From Whole Blood Using Parallel Spiral Microchannels With U-Shaped Cross-Section

2021 ◽  
Author(s):  
Amirhossein Mehran ◽  
Peyman Rostami ◽  
Mohammad Said Saidi ◽  
Bahar Firoozabadi ◽  
Navid Kashaninejad
Keyword(s):  
Cross Section ◽  
High Throughput ◽  
Whole Blood ◽  
Blood Cells ◽  
High Efficiency ◽  
Rectangular Cross Section ◽  
White Blood Cells ◽  
Label Free ◽  
Entire Cross Section ◽  
Shaped Cross Section

Rapid isolation of white blood cells (WBCs) from whole blood is an essential part of any WBC examination platform. However, most conventional cell separation techniques are labor-intensive and low throughput, require large volumes of samples, need extensive cell manipulation, and have low purity. To address these challenges, we report the design and fabrication of a passive, label-free microfluidic device with a unique U-shaped cross-section to separate WBCs from whole blood using hydrodynamic forces that exist in a microchannel with curvilinear geometry. It is shown that the spiral microchannel with a U-shaped cross-section concentrates larger blood cells (e.g., WBCs) in the inner cross-section of the microchannel by moving smaller blood cells (e.g., red blood cells (RBCs) and platelets) to the outer microchannel section and preventing them from returning to the inner microchannel section. Therefore, it overcomes the major limitation of a rectangular cross-section where secondary Dean vortices constantly enforce particles throughout the entire cross-section and decrease its isolation efficiency. Under optimal settings, more than 95% of WBCs can be isolated from whole blood under high-throughput (6 ml/min), high-purity (88%), and high-capacity (180 ml of sample in 1 hour) conditions. High efficiency, fast processing time, and non-invasive WBC isolation from large blood samples without centrifugation, RBC lysis, cell biomarkers, and chemical pre-treatments make this method an ideal choice for downstream cell study platforms.

Sign in / Sign up

Export Citation Format

Share Document