A Method for Investigating the Coefficient of Friction in Tube Sinking through Conical Dies

1965 ◽  
Vol 7 (3) ◽  
pp. 279-282 ◽  
Author(s):  
G. G. Moore ◽  
J. F. Wallace
Keyword(s):  
Experimental Technique ◽  
Coefficient Of Friction ◽  
Experimental Results ◽  
The Coefficient Of Friction ◽  
Further Development ◽  
Continuous Determination

A theory, apparatus and experimental technique for the continuous determination of the coefficient of friction, μ, in tube sinking are briefly discussed and illustrated by some experimental results. The values of μ which have been obtained are lower than those usually accepted for evaluation of tube sinking theories. Suggestions are made for the further development of the technique.

Determination of coefficient of friction between the equine foot and different ground surfaces: an in vitro study

2006 ◽  
Vol 3 (4) ◽  
pp. 191-198 ◽  
Author(s):  
Nicolas J Vos ◽  
Dirk J Riemersma
Keyword(s):  
Coefficient Of Friction ◽  
Force Plate ◽  
Ground Surface ◽  
In Vitro Study ◽  
Gravity Force ◽  
Uniform Motion ◽  
The Coefficient Of Friction ◽  
Equine Industry

AbstractSlippery surfaces are a continuous concern in equine veterinary practice during both treatment and orthopaedic work-ups, especially when horses have to trot on circles. Sliding of the equine foot on the ground with the potential of injury is prevented if the horizontally acting accelerating or decelerating forces on the foot do not exceed maximal friction. Friction can be calculated and therefore anticipated if the coefficient of friction (μ) between the foot of the horse and the particular ground surface is known. Friction between shod and unshod cadaver equine hooves and different ground surfaces (concrete, tarmac and rubber) was determined by pulling the hooves horizontally in a uniform motion. Horizontal forces (Fh) were measured on a force plate and with a portable digital electronic force meter. The coefficient of friction (μ) was calculated as the quotient between Fh and the gravity force (N) of the object, hence: μ = Fh /N. This study has shown that the coefficient of friction between equine hooves and a specific ground surface can be determined using a portable digital force meter or a force plate. Friction significantly depended not only on the type of surface but also on shoeing of the equine foot. Bare feet showed more friction with the hard surfaces (bricks and tarmac), the shod feet showing more friction with the rubber surfaces. Coefficients of friction could be used to estimate the possibility of injuries occurring in the equine industry during exercise and/or lameness or pre-purchase examinations.

scholarly journals Determination of the coefficient of friction using spinning motion

2016 ◽  
Vol 147 ◽  
pp. 012024
Author(s):  
S Alaci ◽  
F C Ciornei ◽  
C Filote ◽  
I C Romanu ◽  
C P Nastaca
Keyword(s):  
Coefficient Of Friction ◽  
The Coefficient Of Friction

Study on the Friction and Wear Characteristics of Tungsten Carbide and Zirconium With Phosphor-Containing Liquid

2016 ◽  
Vol 139 (3) ◽  
Author(s):  
Myeong-Woo Ha ◽  
Kwang-Hee Lee ◽  
Chul-Hee Lee ◽  
Jong-Myung Choi ◽  
Jun-Wook An
Keyword(s):  
Tungsten Carbide ◽  
Coefficient Of Friction ◽  
Contact Surface ◽  
Friction And Wear ◽  
Yttrium Aluminum Garnet ◽  
Experimental Results ◽  
Wear Characteristics ◽  
Hard Materials ◽  
The Coefficient Of Friction ◽  
Friction And Wear Characteristics

The dispenser ejects the ceramic filler and phosphor-containing liquid for making various products. When the particle-containing liquid is ejected under high-velocity conditions, however, the ejection reliability decreases because of the wear of the contact surface between the rod and nozzle even though these components are made of hard materials. It is therefore necessary to characterize the friction and wear properties of the hard materials, tungsten carbide (WC) and zirconium (Zr), with the high-viscosity liquid-containing nitride or yttrium aluminum garnet (YAG) particles under reciprocating conditions. Particle contents of 15 wt.% and 30 wt.% are added to the liquid. A reciprocating test was implemented to this end, and WC and Zr specimens were used. The liquid used in the experiment contains nitride and YAG. The experimental results show that the particles inside the liquid are worn out, leading to particle lubrication and the decrease in the coefficient of friction. Also, it is confirmed that the more the particles are, the less the coefficient of friction is due to particle lubrication. For each experimental condition, the coefficient of friction is measured and compared. Moreover, the contact surface of the specimen is analyzed using an electron microscope, and a profilometer is used to measure the surface roughness of the specimen before and after the test. The reciprocation friction and wear characteristics of WC and Zr with phosphor-containing liquid are evaluated by analyzing the experimental results.

On the Mechanics of Wire Drawing

1961 ◽  
Vol 83 (4) ◽  
pp. 523-529 ◽  
Author(s):  
C. T. Yang
Keyword(s):  
Theoretical Analysis ◽  
Shear Deformation ◽  
Coefficient Of Friction ◽  
Close Agreement ◽  
Wire Drawing ◽  
Experimental Results ◽  
Strain Gages ◽  
Drawing Force ◽  
The Coefficient Of Friction ◽  
Wire Resistance

Split-die technique was adopted to find the coefficient of friction in wire drawing directly from experiment. Simple dynamometers with wire resistance strain gages were used for measuring separating force and drawing force instead of cumbersome equipment used by former researchers. Reasonably good results were obtained. The effect of the land or parallel portion in the die on the coefficient of friction was indicated in the results. Its importance was emphasized. A theoretical equation of the drawing stress with the effect of land considered was derived. Using the coefficient of friction obtained by the split-die method, drawing stresses were calculated from the derived equation. A comparison of the theoretical and experimental drawing stresses was made. Results were tabulated and plotted. It was concluded that including the land in the analysis of wire drawing is important and further research in analyzing the shear deformation must be pursued in order to get a close agreement between theoretical analysis and experimental results.

Power Analysis of Cold Strip Rolling

1963 ◽  
Vol 85 (1) ◽  
pp. 77-88 ◽  
Author(s):  
B. Avitzur
Keyword(s):  
Coefficient Of Friction ◽  
Power Analysis ◽  
Simple Procedure ◽  
Simple Expression ◽  
Optimum Conditions ◽  
Strip Rolling ◽  
The Coefficient Of Friction ◽  
Separation Force ◽  
Cold Strip Rolling

In a previous paper criteria for maximum possible reduction were developed. A simple procedure for the experimental determination of the coefficient of friction was introduced. In this paper a solution for the efficiency is presented. A term called “Minimum Required Reduction,” which was briefly mentioned earlier [2], is discussed in detail. The results of experimental work for the determination of the coefficient of friction are described. A simple expression for the separation force is given. Finally, a procedure for optimum operation is suggested. The controllable variables are pointed out and the steps in the choice of the optimum conditions are described.

scholarly journals THE SCHEMATIZATION FOR TIDAL COMPUTATIONS IN CASE OF VARIABLE BOTTOM SHAPE

1972 ◽  
Vol 1 (13) ◽  
pp. 132
Author(s):  
J.J. Dronkers
Keyword(s):  
Coefficient Of Friction ◽  
Coastal Waters ◽  
Physical Models ◽  
Practical Case ◽  
Two Dimensional ◽  
Physical Methods ◽  
Variable Bottom ◽  
The Coefficient Of Friction ◽  
Shallow Coastal Waters

Mathematical and physical methods can be applied for tidal studies. After general considerations on these methods, some practical aspects of tidal computations are discussed, in particular the schematization for tidal computations in case of variable bottom shape in shallow coastal waters. The relation with the coefficient of friction is dealt with. A combined one- and two dimensional tidal computation is considered. Also an example is given of the determination of the coefficient of friction in a very shallow region; the variations, which are found in this practical case are discussed. 1. General considerations on the application of mathematical and physical methods for tidal studies. Tidal problems may be solved by means of mathematical or physical models. Both kinds of models are approximations of the reality; in some respects in a different way.

Determination of Tire-Road Friction Coefficients for Skid Mark Analysis

1985 ◽  
Vol 13 (1) ◽  
pp. 41-64
Author(s):  
W. R. Garrott ◽  
D. A. Guenther
Keyword(s):  
Experimental Study ◽  
Coefficient Of Friction ◽  
Friction Coefficients ◽  
Pickup Truck ◽  
The Road ◽  
Heavy Trucks ◽  
Road Friction ◽  
Brake Application ◽  
The Coefficient Of Friction

Abstract An experimental study was made to compare the validities of methods currently used by accident reconstructionists to determine the coefficient of friction between the road and the vehicle tires at the time of an incident. This value could then be used in conjunction with skid mark length and vehicle weight to calculate the prebraking speed of the vehicle. Three automobiles and three trucks with a variety of tires and loadings were used on a variety of pavements. The accuracy and area of applicability of each of four methods for obtaining friction coefficients were determined by relating the prebraking speed calculated from each to the actual speed at the time of brake application. All four methods were satisfactory for automobiles and the pickup truck used, but only two were acceptable for heavy trucks. The most valid coefficients are obtained from skid mark lengths obtained under conditions duplicating those in an incident.

Sign in / Sign up

Export Citation Format

Share Document