Assessment of Container Mountings in Modular Offshore Platform Designs for Arctic Regions

2012 ◽  
Author(s):  
Josefine Michel ◽  
Patrick Kaeding
Keyword(s):  
Friction Coefficient ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Offshore Platform ◽  
Harsh Environment ◽  
Offshore Platforms ◽  
Friction Coefficients ◽  
Cold Temperatures ◽  
Elastic Range ◽  
Arctic Regions

Regularly the twistlock system is used to mount containers on container vessels or on offshore platforms as service containers in normal climate regions. In this paper the twistlock system is analyzed with respect to mounting auxiliary systems as well as accommodation and service modules to the deck of offshore platforms in arctic regions. When the twistlock systems are used in harsh environment it is also important that the twistlocks withstand the acting forces without great displacements and without exceeding the elastic range. But in arctic regions the mountings must resist additional forces due to ice interaction, cold temperatures and small friction coefficients. Because the existing rules do not include regulations how to analyze the strength of these mountings in arctic regions the influence of the friction coefficients and the Young’s modulus were of interest in this study. This paper summarizes some numerical works on these new discoveries. The results of the computations show that the Young’s modulus has no influence on the stress and the displacement of the bodies. However, the friction coefficient has influence on the stress specified in the simulations for large roll angles.

Dimensioning of Twistlocks in Modular Offshore Platform Designs for Arctic Regions

2013 ◽  
Author(s):  
Josefine Michel ◽  
Patrick Kaeding
Keyword(s):  
Regression Analysis ◽  
Friction Coefficient ◽  
Offshore Platform ◽  
Roll Angle ◽  
Offshore Platforms ◽  
Arctic Regions

To mount service modules in a flexible manner on offshore platforms twistlock systems are used. If the application is not in accordance with standard conditions the existing regulations are not sufficient. Therefore new regulations with appropriate dimensioning equations must be generated. The results of the OMAE 2013 paper “Assessment of Container Mountings in Modular Offshore Platform Designs for Arctic Regions” are applied in this paper to reach such equations. The stress on twistlocks which mount standard containers to the offshore platform deck in arctic regions depends on roll angle of the offshore platform and friction coefficient — depending on temperature — and is analyzed by regression analysis in this paper. The results show that a local twistlock system can be used to simplify the calculation. Also the application of a crane module is simulated. The regression analysis is divided into two parts — the cone and the base of the twistlock: these parts take most of the load again depending on roll angle and friction coefficient. The result of this paper consists of dimensioning equations for these two different applications of twistlock systems in arctic regions.

scholarly journals Pressure Distributions of Drum Brakes

1996 ◽  
Author(s):  
Yuan Mao Huang ◽  
J. S. Shyr
Keyword(s):  
Friction Coefficient ◽  
Young’S Modulus ◽  
Modulus Of Elasticity ◽  
Young's Modulus ◽  
Arc Length ◽  
Pressure Distributions ◽  
Young’S Modulus Of Elasticity ◽  
Brake Drum ◽  
Drum Brakes ◽  
Lining Plate

Abstract With the assumptions that the interface between the brake drum and the lining plates is perfect contact, that the friction coefficient is constant, that the thermal effect is neglected, that the brake drum and metal shoes are rigid, the pressure distributions of drum brakes are studied by using the boundary element method. The constant element is used in the two dimensional model of the drum brake for simplicity and economy. The pressure distributions on the metal shoe and the lining plate and the friction force versus the effective cam lift are compared and show good agreement with the available data. The effects of the Young’s modulus of elasticity, the angle of the arc length, the friction coefficient, the location and the thickness of the lining plate, the Young’s modulus of elasticity and the angle of the arc length of the metal shoe, and the angle of the actuating force on the pressure distributions of the drum brakes are then studied.

scholarly journals Investigation of Nano-Mechanical and- Tribological Properties of Hydrogenated Diamond Like Carbon (DLC) Coatings

2016 ◽  
Vol 33 (6) ◽  
pp. 769-776 ◽  
Author(s):  
Y.-R. Jeng ◽  
S. Islam ◽  
K-T. Wu ◽  
A. Erdemir ◽  
O. Eryilmaz
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Friction Coefficient ◽  
Young’S Modulus ◽  
Tribological Properties ◽  
Young's Modulus ◽  
Chemical Vapour ◽  
Diamond Like Carbon ◽  
Dlc Coatings ◽  
Mechanical And Tribological Properties

AbstractHydrogenated diamond like Carbon (H-DLC) is a promising lubricious coating that attracted a great deal of interest in recent years mainly because of its outstanding tribological properties. In this study, the nano-mechanical and -tribological properties of a range of H-DLC films were investigated. Specifically, four kinds of H-DLC coatings were produced on Si substrates in pure acetylene, pure methane, 25% methane + 75% hydrogen, 50% methane + 50% hydrogen discharge plasmas using a plasma enhanced chemical vapour deposition (PECVD) system. Nano indentation was performed to measure the mechanical properties such as hardness and young's modulus and nanoscartching was performed to investigate the frictional behavior and wear mechanism of the H-DLC samples in open air. Moreover, Vickers indentation method was utilized to assess the fracture toughness of the samples. The results revealed that there is a strong correlation between the mechanical properties (hardness, young's modulus, fracture toughness) and the friction coefficient of DLC coatings and the source gas chemistry. Lower hydrogen to carbon ratio in source gas leads to higher hardness, young's modulus, fracture toughness and lower friction coefficient. Furthermore, lower wear volume of the coated materials was observed when the friction coefficient was lower. It was also confirmed that lower hydrogen content of the DLC coating leads to higher wear resistance under nanoscratch conditions.

scholarly journals On Pressure Distributions of Drum Brakes

1999 ◽  
Vol 124 (1) ◽  
pp. 115-120 ◽  
Author(s):  
Yuan Mao Huang ◽  
J. S. Shyr
Keyword(s):  
Friction Coefficient ◽  
Young’S Modulus ◽  
Modulus Of Elasticity ◽  
Young's Modulus ◽  
Drum Brake ◽  
Pressure Distributions ◽  
Young’S Modulus Of Elasticity ◽  
Brake Drum ◽  
Drum Brakes ◽  
Lining Plate

Based on the assumptions that there is perfect contact at the interface between the brake drum and the lining plates, the friction coefficient is constant, the thermal effect is neglected, and the brake drum is a rigid body, the pressure distributions of drum brakes were studied by using the boundary element method. The constant element is used in the two-dimensional model of the drum brake for simplicity and economy. The friction force versus the effective lift at the actuation edge and the location of the maximum pressure are compared and indicate a good correlation with existing data. The effects of the Young’s modulus of elasticity of the metal shoe, the arc lengths of the metal shoe and lining plate, the location, the thickness, the friction coefficient, the Young’s modulus of elasticity of the lining plate, and the angle of actuation force on the pressure distributions were then studied. By selecting proper values of these parameters, a drum brake can be designed to have a more uniform pressure distribution and a longer life.

Friction Analysis in Needle Insertion Into Soft Tissue

2021 ◽  
Author(s):  
Yingda Hu ◽  
Murong Li ◽  
Yong Lei
Keyword(s):  
Friction Coefficient ◽  
Young’S Modulus ◽  
Friction Force ◽  
Young's Modulus ◽  
Surface Friction ◽  
Needle Insertion ◽  
Contact Forces ◽  
Diagnostic Methods ◽  
Tissue Pressure ◽  
Preoperative Diagnostic

Abstract As one of the preoperative diagnostic methods, needle insertion is widely used for its safety and effectiveness. Recently, robotic needle insertion systems have been under active developments. Hence needle insertion experiments are essential for system verifications, in which the interactions between needle and tissue is a major focus for needle-tissue interactive models, and the friction between the needle and tissue is an important factor. In these experiments, the friction coefficient can be affected by many factors, such as insertion speed, needle-tissue deformation and contact forces. In this paper, to study and analyze the influence of various variables on friction force and friction coefficient, three variables, i.e., tissue pressure on needle, needle insertion velocity and Young’s modulus of the tissue, are systematically studied by constructing a testbed, in which the radial surface friction is converted into equivalent plane friction based on the assumption that the distribution of the normal force and friction force on the needle is uniform for the whole needle outer surface. The experimental results show that the variation range of friction coefficient is 0.122–0.341. The friction coefficient decreases with the increase of pressure and increases with the increase of velocity, while Young’s modulus have a small effect on the friction coefficient.

THE INFLUENCE OF REDUCING TEMPERATURE ON CHANGING YOUNG’S MODULUS AND THE COEFFICIENT OF FRICTION OF SELECTED SLIDING POLYMERS

Tribologia ◽  
2018 ◽  
Vol 279 (3) ◽  
pp. 107-111
Author(s):  
Anita PTAK ◽  
Piotr KOWALEWSKI
Keyword(s):  
Friction Coefficient ◽  
Young’S Modulus ◽  
Coefficient Of Friction ◽  
Tribological Properties ◽  
Young's Modulus ◽  
Polymeric Materials ◽  
Kinetic Friction ◽  
Mechanical And Tribological Properties ◽  
Pin On Disc ◽  
The Coefficient Of Friction

For the polymeric materials, changing of the temperature causes changes in mechanical and tribological properties of sliding pairs. The goal of the present study was to determine the change in Young's modulus and kinetic friction coefficient depending of the temperature. Three thermoplastic polymers, PA6, PET and PEEK, were tested. These materials cooperated in sliding motion with a C45 construction steel disc. As part of the experiment, the Young's modulus tests (by 3-point bending method) and kinetic friction coefficient studies (using pin-on-disc stand) were carried out. The temperature range of mechanical and tribological tests was determined at T = –50°C±20°C. Comparing the results of mechanical and tribological properties, there is a tendency to decrease the coefficient of friction as the Young's modulus increases while reducing the working temperature.

Evaluation of Young's Modulus and Yield Strength of Thin Film Structural Material Using Nanoindentation Technique

1999 ◽  
Vol 562 ◽  
Author(s):  
Dongil Son ◽  
Yun-Hee Lee ◽  
Jeong-Hoon Ahn ◽  
Dongil Kwon
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Yield Strength ◽  
Film Thickness ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Surface Condition ◽  
Sensors And Actuators ◽  
Elastic Range ◽  
Silicon Bulk

ABSTRACTAluminum films have wide applications in micromechanical devices such as micro sensors and actuators. Therefore, their mechanical properties are very important for reliability evaluation. However, there is no standardized method to evaluate the mechanical properties of the materials used in MEMS(microelectromechanical system) devices since the measured mechanical properties are influenced by many factors such as the surface condition of materials, intrinsic limit of the measurement device, etc. Hence, it was intended to evaluate the mechanical properties of thin film, which is important in its mechanical operation. Because MEMS devices are usually operated in the elastic range, Young's modulus and yield strength were evaluated by using a microcantilever beam technique. First, A1 cantilever beams were fabricated using the silicon bulk micromachining technology to have various film thicknesses. The load-displacement curves during beam bending by nanoindentation method were then obtained. The linear relationship of the curve in elastic range was utilized in deriving Young's modulus of the A1 film, which gave reproducible results regardless of film thickness. In the high load range, the deviation from the linear relation was detected, so that yield strength of A1 film could be evaluated. It was found that the yield strength increases with decreasing film thickness. By applying the misfit dislocation theory and the Hall-Petch relationship, the theoretical estimation could predict the trend of yield strength.

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