scholarly journals Investigation of the fluids influence on change of sandstones collectors mechanical properties during saturation and degassing

2019 ◽  
Vol 109 ◽  
pp. 00103
Author(s):  
Serhii Tynyna ◽  
Vasyl Babenko

The article discusses the effect of fluids on the properties of rocks. It is known that surface active environments, including gas, can significantly change the mechanical characteristics of solids. To establish the dependence of the effect of methane on the strength characteristics of rocks, the results of full-scale and laboratory studies are considered. The experiments were carried out on samples of outburst sandstone formation m3, taken at a depth of 915 m. Analysis of research results allowed to establish the effect of changes in gas saturation of rocks on their mechanical properties before and after degassing and partial discharge of experimental areas after they have been worked by lavas along m3 formation. It has been established that the reason for the increase in drillability and strength of sandstones was their degassing, and not a change in the stress state of the environment. This led to a change in the deformation properties of rocks in gas-saturated and degassed states.

2021 ◽  
Vol 87 (3) ◽  
pp. 51-57
Author(s):  
Yu. V. Bugrov ◽  
A. A. Hlybov ◽  
M. K. Chegurov

The indicators of the brittleness and viscosity of metals calculated from their mechanical properties are considered with allowance for the stress state proceeding from the results of tensile testing of cylindrical smooth and notched samples of perlite 16KhSN, martensitic-aging (maraging) 03Kh11N10M2T, and austenitic 10Kh11N23T3MR steels. Tests were carried out on a UEM-10TM tensile strength testing machine, deformation diagrams developed on a scale of ~50:1 at a deformation rate of 5 mm/min. The sample size before and after testing were measured using a micrometer and an ISA-2 comparator with an accuracy of ±10–3 mm. Pendulum impact bending tests were carried out on a MK15 with the same cylindrical notched samples used to plot the plasticity and viscosity diagrams depending on the Bridgman stress state stiffness index. The new indicators of the brittleness λ = εk/η and viscosity η = (Sk/σb) – 1 (where εk = ln(1/(1 – ψk)) is the true limit plasticity) are proposed proceeding from the testing data. The special feature of the brittleness index λ is growth of the index with increase in the metal strength, e.g., due to pre-deformation or strengthening heat treatment procedures. However, a decrease in the groove radius on the samples, i.e., an increase in the Bridgman stress state stiffness, has almost no effect on the brittleness value λ, but is accompanied by a correlation decrease in the values of the viscosity indices η and the ultimate ductility εk of steels. The curves of the temperature dependences of the mechanical properties of steels 16KhSN and 03Kh11N10M2T show that anomalies in the brittleness indices λ observed at elevated test temperatures can be attributed to the structural transformations like increase in the grain size of 16KhSN steel or in the amount of the residual austenite in 03Kh11N10M2T steel due to reverse martensitic transformation. In this case, the temperature dependences of the viscosity η and brittleness λindicators change in the opposite way.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Cheng-Jin Deng ◽  
Fa-Ning Dang ◽  
Xing-Zhou Chen ◽  
Zhe Miao ◽  
Li-Li Chen

Insufficient compactness of rockfill materials may potentially cause excessive deformation of a concrete face rockfill dam (CFRD), thus resulting in cracking of the face slab and leakage of the dam body, thereby requiring reinforcement treatment. To date, there are no effective measures in strengthening rockfill materials. In this study, self-compacting mortar (SCM) was applied to the Shibaozhai CFRD in Gansu Province, China, to test the effectiveness of grouting reinforcement. Simultaneously, an indoor triaxial shear test was conducted to investigate the changes in the mechanical properties of rockfill materials before and after the grouting reinforcement. The on-site test results showed that the rockfill reached the desired porosity after grouting and grouting reinforcement enhanced the cementation degree of rockfill materials while maintaining uninterrupted drainage capacity, which met the requirements of rockfill grouting for the face rockfill dam. The results of the triaxial shear test indicated that the cohesive force of the rockfill materials rose by 3.95 times and the modulus increased by 7.24 times after grouting reinforcement,significantly enhancing the mechanical and deformation properties of the rockfill. An increase in the content of coarse particles was shown to enhance the stability of cementitious structures, which leads to a better skeleton effect and thereby raises the effectiveness of the grouting reinforcement. The rockfill materials also exhibited strain-softening characteristics following the grouting reinforcement. The research showed that grouting reinforcement technology is suitable for managing the deformation of high CFRDs or reinforcing ill rockfill dams.


2020 ◽  
Vol 38 (1A) ◽  
pp. 34-42
Author(s):  
Ibrahim M. AL-Sudani ◽  
Samir A. Al-Rabii ◽  
Dhafir S. Al-Fattal

 This research aims to study the effect of using the anodizing process on the corrosion rate, mechanical properties as well as the fatigue life for aluminum alloy (7075-T73), which is one of the most commonly used aluminum alloy in production of aircrafts, vehicles and ships structures. The anodizing process was employed through using sulfuric acid for time (20) min in a salty atmosphere. The mechanical properties and fatigue life of the AA7075-T73 were obtained before and after the anodizing process. All the results were listed in detailed tables and figures for comparison purpose. Generally, these results showed a decrease in corrosion rate by (155.06%) in comparison with untreated, an increase in hardness by (21.54%) and a slight decrease in fatigue life by (7.7%) due to anodizing for a time of 20 min at the stress level of (σa = 491.10 MPa). It was concluded that this technique could be applied on other aluminum alloys in order to know the magnitude of change in the mechanical characteristics and their fatigue life.


2010 ◽  
Vol 112 (6) ◽  
pp. 1260-1262 ◽  
Author(s):  
Yasunari Otawara ◽  
Kuniaki Ogasawara ◽  
Hiroshi Kashimura ◽  
Yoshitaka Kubo ◽  
Akira Ogawa ◽  
...  

The mechanical properties of titanium-alloy aneurysm clips after long-term implantation in the human cranium are unclear. The characteristics of a Yasargil titanium aneurysm clip were evaluated after long-term implantation for 12 years in a patient with a cerebral aneurysm. The closing forces of the retrieved clip before and after implantation were approximately equal. The bending test showed no differences between the retrieved and control clips. Titanium oxide and calcium were identified on the surface of the retrieved clip, which indicated the formation of corrosion-resistant layers. Titanium-alloy clips retain their mechanical properties in the human cranium for a long time.


2015 ◽  
Vol 749 ◽  
pp. 159-163 ◽  
Author(s):  
D. Edison Selvaraj ◽  
R. Vijayaraj ◽  
U. Satheeshwaran ◽  
J. Nancy ◽  
C. Pugazhendhi Sugumaran ◽  
...  

Cables are an integral part of the power transmission and distribution network. As the voltage level increases, amount of insulation used in the cable increases. Therefore a need arises for a material with better insulation characteristics to be used in cables. The dielectric strength of cable insulation depends on many factors such as the existence of filler material in the insulation. In this work, laboratory studies on a new filler material for cable insulation have been conducted. The influence of Silicon dioxide (SiO2) filler on the dielectric and mechanical properties of polyvinyl chloride (PVC) cable were analyzed. Comparison is made between the result of measurement and the actual value of the pure specimen. From the results, it is shown that the filler material has improved the dielectric and mechanical properties of the cable insulation.


2021 ◽  
Vol 2 (1(58)) ◽  
pp. 21-25
Author(s):  
Anastasiia Lokatkina ◽  
Tetiana Prikhna ◽  
Viktor Moshchil ◽  
Pavlo Barvitskyi ◽  
Oleksandra Borimsky ◽  
...  

The object of research is HfB2, ZrB2 and ceramics composition HfB2-30 % SiC and ZrB2-20 % SiC, ZrB2-20 % SiC-4 % Si3N4 obtained under high pressure, their mechanical characteristics before and after heating to high temperatures and temperatures of beginning of melting. The research was conducted in order to create new effective refractory materials for use in the aerospace industry. Therefore, the melting temperatures of sintered materials and the effect of heating on their mechanical properties were also studied. Additives (ZrB2-20 % SiC and HfB2-30 % SiC) although led to a decrease in specific gravity. But increased hardness (by 17 % and 46 % in the case of ZrB2 and HfB2, respectively) and fracture toughness (by 40 % and 21 % in the case of ZrB2 and HfB2, respectively). However, significantly reduced the onset of melting temperature in vacuum to 2150–2160 °C. Materials sintered from ZrB2 and HfB2 was not melted after heating to 2970 °C. After heating to a melting point of 2150–2160 °C (in the case of materials with additives) and to temperatures of 2970 °C (in the case of materials sintered with ZrB2 or HfB2), the hardness and fracture toughness decreased. Thus, the hardness of the material prepared from ZrB2 decreased by 19 % and its fracture toughness – by 18 %, and of that prepared from ZrB2–20 % SiC – by 46 % and 32 %, respectively. The hardness of the material prepared from HfB2 decreased by 46 %, its fracture toughness – by 55 %, and of that prepared from HfB2-30 % SiC, after heating decreased by 40 %, but its fracture toughness increased by 15 %. The sintered HfB2 (with a density of 10.4 g/cm3) before heating showed a hardness of HV(9.8 N)=21.27±0.84 GPa, HV(49 N)=19.29±1.34 and HV(98 N)=19.17±0.5, and fracture toughness K1C(9.8 N)=0.47 MH·m0.5, and ZrB2 with a density of 6.2 g/cm3 was characterized by HV(9.8 N)=17.66±0.60 GPa, HV(49 N)=15.25±1.22 GPa and HV(98 N)=15.32±0.36 GPa, K1C(9.8 N)=4.3 MH·m0.5. Material sintered with HfB2-30 % SiC (density 6.21 g/cm3) had Hv(9.8 N)=38.1±1.4 GPa, HV(49 N)=27.7±2.8 GPa, and K1C(9.8 N)=8.1 MH·m0.5, K1C(49 H)=6.8 MH·m0.5. The sintered with ZrB2-20 % SiC material had density of 5.04 g/cm3, HV(9.8 N)=24.2±1.9 GPa, HV(49 N)=16.7±2.8 GPa, K1C(49 H)=7.1 MH·m0.5. The SiC addition to the initial mixture significantly reduces the elasticity of the materials.


2022 ◽  
Vol 1049 ◽  
pp. 3-10
Author(s):  
Evgeny Remshev ◽  
Zainudin Rasulov ◽  
Sergey Voinash ◽  
Irina Vornacheva ◽  
Victoria Alexandrovna Sokolova ◽  
...  

We investigated the possibility of using an organofluorine coating on parts of the "Screen" type made by cold stamping from refractory metals, in particular niobium. The paper also presents the results of a study of the mechanical characteristics of samples with acoustic-emission accompaniment and the hardness values before and after applying the organofluorine composition. The surface of parts with and without coating after convolution is studied. It is shown that it is possible to prevent loss of stability during the first operation of the technological process, as well as to reduce the number of operations by eliminating annealing between subsequent operations of drawing with thinning.


2018 ◽  
Vol 69 (05) ◽  
pp. 381-389
Author(s):  
MENGÜÇ GAMZE SÜPÜREN ◽  
TEMEL EMRAH ◽  
BOZDOĞAN FARUK

This study was designed to explore the relationship between sunlight exposure and the mechanical properties of paragliding fabrics which have different colors, densities, yarn counts, and coating materials. This study exposed 5 different colors of paragliding fabrics (red, turquoise, dark blue, orange, and white) to intense sunlight for 150 hours during the summer from 9:00 a.m. to 3:00 p.m. for 5 days a week for 5 weeks. Before and after the UV radiation aging process, the air permeability, tensile strength, tear strength, and bursting strength tests were performed. Test results were also evaluated using statistical methods. According to the results, the fading of the turquoise fabric was found to be the highest among the studied fabrics. It was determined that there is a significant decrease in the mechanical properties of the fabrics after sunlight exposure. After aging, the fabrics become considerably weaker in the case of mechanical properties due to the degradation in both the dyestuff and macromolecular structure of the fiber


Author(s):  
P.A. Popov ◽  
◽  
D.V. Gruznov ◽  
S.V. Tokarev ◽  
◽  
...  

The article presents the results of determining the relationship between the total microbial number and microbial ATP on the surface of milking equipment before and after treatment with neutral anolyte ANK-SUPER. The possibility of using the ATP-bioluminescence method to control the quality of sanitation of milking equipment on dairy farms is shown. Laboratory studies revealed a proportional relationship between the level of bacterial ATP and the number of bacteria on the surface of milking equipment before and after sanitation.


2019 ◽  
Vol 70 (10) ◽  
pp. 3469-3472

Weldability involves two aspects: welding behavior of components and safety in operation. The two aspects will be reduced to the mechanical characteristics of the elements and to the chemical composition. In the case of steel reinforcing rebar’s, it is reduces to the percentage of Cech(carbon equivalent) and to the mechanical characteristics: the yielding limit, the ultimate limit, and the elongations which after that represent the ductility class in which the re-bars is framed. The paper will present some types of steel reinforcing rebar’s with its mechanical characteristics and the welding behavior of those elements. In the current work, process-related behavior of welded reinforcement, joint local and global mechanical properties, and their correlation with behavior of normal reinforcement and also the mechanical performance resulted in this type of joints. Keywords: welding behavior, ultimate limit, reinforcing rebar’s


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