scholarly journals Shearing Mechanism of Preformed Wire for Metal Zipper

2020 ◽  
Vol 61 (708) ◽  
pp. 13-19
Author(s):  
Chikako HIROMI ◽  
Shigeru TSUCHIDA ◽  
Futoshi KOZATO ◽  
Hiroko MIKADO ◽  
Shingo KAWAMURA ◽  
...  
Keyword(s):  
Shearing Mechanism

scholarly journals Role of Shearing Dispersion and Stripping in Wax Deposition in Crude Oil Pipelines

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4325
Author(s):  
Zhihua Wang ◽  
Yunfei Xu ◽  
Yi Zhao ◽  
Zhimin Li ◽  
Yang Liu ◽  
...  
Keyword(s):  
Crude Oil ◽  
Flow Rate ◽  
Critical Flow ◽  
Wax Deposition ◽  
Dominant Effect ◽  
Critical Flow Rate ◽  
Oil Pipelines ◽  
Oil Flow ◽  
Shearing Mechanism

Wax deposition during crude oil transmission can cause a series of negative effects and lead to problems associated with pipeline safety. A considerable number of previous works have investigated the wax deposition mechanism, inhibition technology, and remediation methods. However, studies on the shearing mechanism of wax deposition have focused largely on the characterization of this phenomena. The role of the shearing mechanism on wax deposition has not been completely clarified. This mechanism can be divided into the shearing dispersion effect caused by radial migration of wax particles and the shearing stripping effect caused by hydrodynamic scouring. From the perspective of energy analysis, a novel wax deposition model was proposed that considered the flow parameters of waxy crude oil in pipelines instead of its rheological parameters. Considering the two effects of shearing dispersion and shearing stripping coexist, with either one of them being the dominant mechanism, a shearing dispersion flux model and a shearing stripping model were established. Furthermore, a quantitative method to distinguish between the roles of shearing dispersion and shearing stripping in wax deposition was developed. The results indicated that the shearing mechanism can contribute an average of approximately 10% and a maximum of nearly 30% to the wax deposition process. With an increase in the oil flow rate, the effect of the shearing mechanism on wax deposition is enhanced, and its contribution was demonstrated to be negative; shear stripping was observed to be the dominant mechanism. A critical flow rate was observed when the dominant effect changes. When the oil flow rate is lower than the critical flow rate, the shearing dispersion effect is the dominant effect; its contribution rate increases with an increase in the oil flow temperature. When the oil flow rate is higher than the critical flow rate, the shearing stripping effect is the dominant effect; its contribution rate increases with an increase in the oil flow temperature. This understanding can be used to design operational parameters of the actual crude oil pipelines and address the potential flow assurance problems. The results of this study are of great significance for understanding the wax deposition theory of crude oil and accelerating the development of petroleum industry pipelines.

Reveal the stacking fault shearing mechanism by its annihilation process in Ni-based single crystal superalloys

2021 ◽  
pp. 111419
Author(s):  
Pengfei Qu ◽  
Wenchao Yang ◽  
Jiarun Qin ◽  
Kaili Cao ◽  
Chen Liu ◽  
...  
Keyword(s):  
Single Crystal ◽  
Stacking Fault ◽  
Annihilation Process ◽  
Shearing Mechanism

Critical Review of Early Age Cycling Effects on the Capacity of Pile to Sleeve Grouted Connections As Treated in ISO 19902

2019 ◽  
Author(s):  
Andi Merxhani ◽  
Jacob Fisker Jensen ◽  
Joao Caetano ◽  
Casper Klintø Christiansen
Keyword(s):  
Compressive Strength ◽  
Experimental Evidence ◽  
Structural Design ◽  
High Performance ◽  
Underlying Mechanism ◽  
Early Age ◽  
Design Code ◽  
Concrete Members ◽  
Jacket Structures ◽  
Shearing Mechanism

Abstract The treatment of early age cyclic loading (EAC) on pile-sleeve grouted connections is one of the challenging problems encountered in the design of offshore jacket structures. ISO 19902 appears to be the only offshore structural design code that quantifies the strength de-rating due to EAC. However, the mechanism of EAC considered in the ISO standard is little understood. Main provision is that the strength reduction due to EAC is considered to be linearly proportional to the compressive strength of the grout. This provision is conservatively applicable for medium strength grouts. However, it is over-conservative when modern high-performance grouts are used, and it can be further argued that it actually loses its physical meaning. Thus, a further investigation into the mechanics of the problem is deemed beneficial in order to understand better its underlying mechanism. Using existing experimental evidence and a simple mechanical model, it is shown that the EAC mechanism considered in ISO 19902 triggers the grout matrix failure mechanism of the grouted connections. This behavior is characteristic of segregating grout materials. The benefit of the approach followed is that it links the interpretation of EAC to the grout material properties. The phenomenon is then understood using methods and experimental results that are well established in concrete mechanics. After a comparison with existing experimental evidence on grouted connections and concrete members, it is suggested that the strength drop for the specific shearing mechanism is independent of the uniaxial compressive strength of the grout material.

High Technology Options for Sheep Shearing III: Chemical and Biological Defleecing

1987 ◽  
Vol 16 (2) ◽  
pp. 68-76
Author(s):  
P. R. W. Hudson
Keyword(s):  
High Technology ◽  
Cost Price ◽  
Shearing Mechanism ◽  
Biological Methods ◽  
The Cost ◽  
Harvesting Costs

Two earlier articles have considered the cost-price squeeze facing the Australian woolgrower, and the solutions being sought to reduce wool harvesting costs. The first concentrated on the improvements to existing shearing methods, especially the shearing mechanism itself. The second summarised the progress of a programme aiming to automate shearing. This concluding article considers the research which has been undertaken to evaluate chemical and biological methods of wool harvesting.

scholarly journals TEM observation of precipitates and their role to mechanical properties in Ti-5553 alloy heated to some temperatures up to 923 K

2020 ◽  
Vol 321 ◽  
pp. 11035
Author(s):  
E. Sukedai ◽  
E. Aeby-Gautier ◽  
M. Dehmas
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Hardening Mechanism ◽  
Transmission Electron ◽  
The Matrix ◽  
Higher Temperature ◽  
Shearing Mechanism ◽  
Hardness Values ◽  
Measured Hardness

A Ti-5553 specimen was continuously heated to 923 K and simultaneously in-situ HEXRD profiles were taken. In addition, specimens heated at the same rate to several temperatures up to 923 K and further quenched were observed by transmission electron microscopy. Based on both results obtained, transformation sequence was clarified, precipitations of ω-, α”iso- and α-phases were confirmed, and size and density of these precipitates were measured. Hardness values of those specimens were also measured. The hardening mechanism was considered as shearing-mechanism for specimens aged at lower temperatures and by-pass one for specimens aged at higher temperature. An attempt of distinction between α”iso - and α-precipitates was also tried. Both precipitates were in needle-like shape and a possibility was suggested by measuring angles between two needle-shape precipitates on {110} of the matrix and comparing with each other.

scholarly journals Application of hybrid microwave thermal extraction techniques for mulberry root bark

2013 ◽  
Vol 17 (5) ◽  
pp. 1311-1315
Author(s):  
Cheng-Chi Wang ◽  
Her-Terng Yau
Keyword(s):  
Thermal Process ◽  
High Performance ◽  
Circulation System ◽  
Operating Parameters ◽  
Root Bark ◽  
Extraction Techniques ◽  
Optimal Operating ◽  
Thermal Extraction ◽  
Shearing Mechanism ◽  
Reliable Basis

The main focus of this paper is the extraction of compounds from the mulberry root bark using a hybrid microwave thermal process. The shearing mechanism and an integrated circulation system, which increases the rate of contact between the solvent and extractive, are studied. The results are analyzed by the Taguchi method and verified by high performance liquid chromatography. Furthermore, the optimal operating parameters of the extraction of mulberry root bark are discussed. The results show that hybrid microwave thermal extraction can successfully extract the active ingredients from mulberry root bark. This is a reliable basis for further researches.

Electrical Conductivity and Hardness Property of CNTs/Epoxy Nanocomposites

2013 ◽  
Vol 701 ◽  
pp. 197-201 ◽  
Author(s):  
Hendra Suherman ◽  
Jaafar Sahari ◽  
Abu Bakar Sulong
Keyword(s):  
Electrical Conductivity ◽  
Epoxy Resin ◽  
High Speed ◽  
Epoxy Nanocomposites ◽  
Electron Microscopic ◽  
Weight Percentage ◽  
Hardness Tester ◽  
Hardness Property ◽  
Shearing Mechanism ◽  
Mechanical Shearing

This study investigates the effect of carbon nanotubes (CNTs) as conductive fillers and epoxy resin as matrix on the electrical conductivity and hardness property. The different CNTs weight percentage (0 ~ 10 wt.%) were added into the epoxy resin. The dispersion of CNTs in epoxy resin was conducted by high speed mixer through mechanical shearing mechanism. The mixture of CNTs/epoxy was poured into the mold and compression molding was conducted for fabrication of CNTs/epoxy nanocomposites. The electrical conductivity and hardness of CNTs/epoxy nanocomposites by several of CNTs loading concentration were measured by the four point probe and dynamic ultra micro hardness tester. Agglomeration of CNTs in epoxy matrix was observed on fractured surface by scanning electron microscopic. Non conductive epoxy polymer becomes conductor as addition of CNTs. Electrical conductivity of CNTs/epoxy nanocomposites were increased with increasing of CNTs loading concentration. Hardness property of CNTs/epoxy nanocomposites ware reached the highest value at 5 wt.%, and then it was decreased.

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