Practice for Calibration of the James Static Coefficient of Friction Machine

2006 ◽  
Author(s):  
Keyword(s):  
Coefficient Of Friction ◽  
Friction Machine ◽  
Static Coefficient Of Friction ◽  
Static Coefficient

scholarly journals DETERMINING THE COEFFICIENT OF FRICTION OF WOOD-BASED MATERALS FOR FURNITURE PANELS IN THE ASPECT OF MODELLING THEIR SHREDDING PROCESS

Wood Research ◽  
2021 ◽  
Vol 66 (5) ◽  
pp. 789-805
Author(s):  
MATEUSZ KUKLA ◽  
ŁUKASZ WARGUŁA ◽  
ALEKSANDRA BISZCZANIK
Keyword(s):  
Coefficient Of Friction ◽  
Kinetic Coefficient ◽  
Drive Unit ◽  
Base Surface ◽  
The Coefficient Of Friction ◽  
Kinematic Coefficient ◽  
Cutting Processes ◽  
Static Coefficient Of Friction ◽  
Static Coefficient ◽  
Selection Of

In order to improve the power selection of the drive unit for the shredding machines,theauthors determine the values of friction coefficients used in the cutting force models. These values consider the friction between steel and such wood-based materials as chipboard, MDF and OSB. The tests concern laminated and non-laminated external surfaces and surfaces subjected to cutting processes. The value of the coefficient of friction for the tested materials is in the range: for the static coefficient of friction 0.77-0.33, and for the kinetic coefficient of friction 0.68-0.25. The highest values of the static and kinematic coefficient of friction were recorded for MDF (non-laminated external surface) and they were equal respectively: 0.77 and 0.68. In turn, thesmallest values of the discussed coefficients were recorded for chipboard (laminated external wood-base surface), which were at the level of 0.33 and 0.25, resp.

scholarly journals Measuring the Static Coefficient of Friction of Non-Fluid Contaminants

2019 ◽  
Vol 63 (1) ◽  
pp. 537-541
Author(s):  
Hunter DeBusk ◽  
Levi Dixon ◽  
Joellen Gill ◽  
Richard Gill
Keyword(s):  
Coefficient Of Friction ◽  
Human Subjects ◽  
Small Samples ◽  
Subjective Ratings ◽  
Slip Event ◽  
Materials Used ◽  
Static Coefficient Of Friction ◽  
Static Coefficient ◽  
Porcelain Tile ◽  
Floor Material

The purpose of our study was to evaluate whether there are differences between measuring the static coefficient of friction (SCOF) of a non-fluid contaminant when it is directly attached to a tribometer test foot, or “Attached”, versus when it is lying loose on the floor, or “Loose”. The non-fluid materials used in this study included Mylar, Cardboard, Terrycloth Bathmat, and Terrycloth Bathmat with Rubberized Silicon Backing; the floor material was porcelain tile. In addition, 10 participants subjectively rated the “slipperiness” of each material by pushing the materials with one foot across the porcelain tile. The findings of this study revealed that within each technique, Attached and Loose, the measurements were consistent and reliable. Furthermore, both techniques resulted in identical ordering of the materials from lowest to highest SCOF, which was verified by the human subjects’ subjective ratings of slipperiness. However, the Loose technique SCOF values were slightly but consistently greater than the Attached technique SCOF values; the Loose tests of the entire bathmats were found to have greater SCOF values when compared to Loose tests of small samples. These findings suggest that when investigating a specific slip event, a practitioner should measure the SCOF of the non-fluid contaminant using the technique which most closely represents the conditions of the slip event.

Testing the Validity of Greenwood and Tripp’s Sum Surface Assumption for Elastic-Plastic Contact

2020 ◽  
Vol 142 (10) ◽  
Author(s):  
Ashutosh Roy ◽  
Bhargava Sista ◽  
Kumar Vemaganti
Keyword(s):  
Surface Roughness ◽  
Finite Element ◽  
Correlation Length ◽  
Coefficient Of Friction ◽  
Rough Surfaces ◽  
Surface Model ◽  
Finite Element Models ◽  
Rigid Plane ◽  
Static Coefficient Of Friction ◽  
Static Coefficient

Abstract The complexity of modeling friction between rough surfaces has prompted many researchers to use Greenwood and Tripp’s sum surface assumption to simplify the analysis. This assumption approximates the contact between two rough surfaces as contact between their equivalent sum surface and a rigid plane. In this work, we develop detailed finite element models to test the sum surface assumption for surfaces with Gaussian and exponential autocorrelation functions. We consider surfaces with differing surface roughness and correlation length values. For each case, we conduct simulations of two rough surfaces interacting in compression followed by shear, and a corresponding equivalent surface model based on the sum surface assumption. Multiple realizations of each parameter combination are simulated to obtain a statistical picture of the responses. We find that (a) the sum surface assumption consistently under-predicts the static coefficient of friction and (b) the equivalent surface model is less accurate for surfaces with differing correlation length-to-surface roughness ratios.

Sign in / Sign up

Export Citation Format

Share Document