The Role of Lubrication in the Cold Heading of Mild Steel

1975 ◽  
Vol 97 (2) ◽  
pp. 144-150 ◽  
Author(s):  
J. L. Tevaarwerk ◽  
A. Plumtree ◽  
R. Sowerby
Keyword(s):  
Mild Steel ◽  
Coefficient Of Friction ◽  
Low Cost ◽  
Steel Wire ◽  
Solid Lubricants ◽  
Minor Role ◽  
Total Force ◽  
Liquid Lubricant ◽  
The Coefficient Of Friction ◽  
A Minor

This work provides information leading to the evaluation of the coefficient of friction for various lubricants during the first blow of a double blow heading operation on AISI 1018 steel wire. A Waterbury-Farrel cold heading machine was instrumented so that the total force and frictional force could be evaluated during the first blow operation. The lubricants investigated fell into four main groups: 1) Lubricants, physically or chemically bonded to the wire; this group included zinc phosphate, 2) Lubricants listed in 1) used together with a petroleum based polar oil, SAE 30 [780 SUS at 80° F (167 × 10−6 m2/s at 27° C)], 3) Liquid lubricants of various viscosities employed with the bare wire, 4) Solid lubricants mixed with a non-polar mineral oil [65 SUS at 80° F (12 × 10−6 m2/s at 27° C)], again used with bare wire. The calculated coefficient of friction was used to indicate the efficiency of the respective lubricants. Liquid lubricants either alone on bare wire or with bonded lubricants proved to be the most successful in reducing the calculated μ value; additives appeared to play a minor role. The results indicate that a low cost liquid lubricant used on bare wire has both economic and operational advantages when cold heading mild steel wire.

Paper 21: Variations in Friction and Wear between Unlubricated Steel Surfaces

1966 ◽  
Vol 181 (15) ◽  
pp. 16-24
Author(s):  
S. W. E. Earles ◽  
D. G. Powell
Keyword(s):  
Wear Rate ◽  
Mild Steel ◽  
Oxide Layer ◽  
Coefficient Of Friction ◽  
Surface Film ◽  
Frictional Heating ◽  
Subsequent Increase ◽  
Track Condition ◽  
The Coefficient Of Friction ◽  
Steel Disc

Experiments have been conducted in a normal atmosphere using a 0·25-in diameter mild-steel pin specimen sliding on a 10-in diameter mild-steel disc. The ranges of normal force and speed are 0·5–10·4 lbf and 20–190 ft/s respectively. Initially the coefficient of friction is comparatively large, and the wear is of the severe metallic form. However, frictional heating causes rapid oxidation of the surfaces and, if the sliding distance is sufficient, the eventual retention of an oxide layer causes a rapid decrease in the coefficient of friction and the wear rate decreases by 3–4 orders of magnitude. At speeds above about 75 ft/s and loads below about 5 lbf the formation, after several hours' sliding, of a continuous oxide layer on the track causes a further reduction in the pin wear rate. At higher loads and/or lower speeds this track condition is not attained. At speeds of 75 ft/s and above there exists a critical load (the magnitude of which depends on speed) above which periodic removals of the surface film(s) occur producing metallic wear and high friction. However, the subsequent increase in oxidation allows conditions of mild wear to be re-established generally within a few seconds. The steady-state coefficient of friction has been observed to be a function of load1/2 × speed, and periodic surface breakdowns found to occur when load1/2 × speed exceeds 170 lbf1/2 ft/s, the frequency decreasing with increasing load or speed.

scholarly journals The coefficient of friction of individual potatoes and various handling materials – Short communication

2012 ◽  
Vol 58 (No. 3) ◽  
pp. 114-117
Author(s):  
C.F.H. Bishop ◽  
A.F.J. Gash ◽  
C. Heslim ◽  
S. Hanney
Keyword(s):  
Mild Steel ◽  
Coefficient Of Friction ◽  
Coefficient Of Variation ◽  
Short Communication ◽  
Dynamic Coefficient ◽  
The Coefficient Of Friction ◽  
Dynamic Coefficient Of Friction

The dynamic coefficient of friction of single potatoes was determined on mild steel, rubber and plastic, for tubers in each of four conditions: dry and dirty, wet and dirty, clean and wet and clean and dry. Steel had the lowest overall mean coefficient of friction. The highest value was recorded for plastic, but this material also had the largest coefficient of variation. Overall, rubber was considered to be the most suitable all-condition material for tubers in a range of conditions.

XXIII.—On the Cohesion of Steel, and on the Relation between the Yield Points in Tension and in Compression.

1908 ◽  
Vol 28 ◽  
pp. 374-381 ◽  
Author(s):  
G. H. Gulliver
Keyword(s):  
Mild Steel ◽  
Yield Point ◽  
Coefficient Of Friction ◽  
External Load ◽  
Frictional Resistance ◽  
Experimental Results ◽  
Cohesive Force ◽  
Metallic Particles ◽  
Resistance To Deformation ◽  
The Coefficient Of Friction

SUMMARY(a) On the assumptions that resistance to deformation is due to simple friction, and that the coefficient of friction is independent of the load, the ratio of the yield point in tension to the yield point in compression, for what is ordinarily known as mild steel, is calculated as 2·384 to 3·384, or as 0·705 to 1. Experimental results so far obtained do not agree well with these figures, the value for the tensile yield point being relatively high, and that for compression relatively low.(b) On the further assumption that a cohesive force acting between the metallic particles gives rise to a frictional resistance which may be added (algebraically) to that due to the effect of the external load, the value of this cohesive force is deduced as equal to 3·384 times the stress which corresponds with the tension yield point, or to 2·384 times that corresponding with the compression yield point. Experimental results from a large number of tests agree very fairly with the calculated figures for the case of tension.

scholarly journals Effect of Micro- and Nano-Sized Carbonous Solid Lubricants as Oil Additives in Nanofluid on Tribological Properties

Lubricants ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 25 ◽  
Author(s):  
Emad Omrani ◽  
Pradeep Menezes ◽  
Pradeep Rohatgi
Keyword(s):  
Coefficient Of Friction ◽  
Canola Oil ◽  
Friction And Wear ◽  
Solid Lubricants ◽  
Lubricating Oil ◽  
Oil Additives ◽  
Load Carrying ◽  
The Coefficient Of Friction ◽  
Pin On Disk ◽  
Worn Surface

The tribological behavior of graphene and graphite as additives in canola oil was investigated with a pin-on-disk tribometer. The wear surfaces of the aluminum pins lubricated with the additive-containing canola oil were analyzed by scanning electron microscopy (SEM). It was found that graphene and graphite as additives in oil show a lower coefficient of friction and wear rate in comparison with neat canola oil. The graphene sheets are more effective than graphite flakes to reduce friction and wear. In addition, there is a proper concentration where the coefficient of friction (COF) and wear are in minimum value. The optimal concentration of the additive in canola oil is about 0.7 wt %. Therefore, the load-carrying capacity and antiwear ability of the lubricating oil are improved. Moreover, the worn surface of aluminum pins is smother in the presence of solid lubricant rather than neat oil.

scholarly journals Sustainability of conservation agriculture adoption and the role lead farmers play in Zimbabwe

2021 ◽  
Vol 49 (2) ◽  
pp. 1-14
Author(s):  
Joe Stevens ◽  
Nyathi ◽  
Salomons
Keyword(s):  
Low Cost ◽  
Conservation Agriculture ◽  
Farming System ◽  
Small Scale ◽  
Minor Role ◽  
Extension Services ◽  
Governmental Organizations ◽  
Non Governmental Organizations ◽  
A Minor ◽  
Agriculture Extension

Conservation Agriculture (CA) has been promoted widely in Zimbabwe through several organizations, including government and non-governmental organizations, to help address food insecurity. The sustainability of donor led interventions has been questioned as they are of limited duration, and some research has reported that farmers stop practicing CA when a project ends. However, agriculture extension services are reported crucial in adopting new agriculture technologies; hence, continued access to services is crucial for the sustainable uptake of CA. The use of farmer-led extension approaches has been used to reach more farmers at low cost to promote CA and for sustainability. The study evaluates the sustainability of CA practices as well as lead farmers roles after the end of Christian Care project activities. The findings reveal continued adoption of CA principles, albeit on a small scale. We conclude that CA has become part of the traditional farming system and recommend labour-saving technologies for the uptake of CA on a greater scale. Government extension support has also continued, although lead farmers played a minor role in these extension activities. Lead farmers alone cannot sustainably provide extension services without institutional support. The recommendation is that public extension systems work closely with lead farmers in communities to efficiently reach farmers and ensure better coordination between NGOs and government extension activities.

scholarly journals Effect of Humidity on Friction of Molybdenum Disulfide Films Produced by Thermal Evaporation on Titanium Substrates

2020 ◽  
pp. 25-33
Author(s):  
Bodhi R. Manu ◽  
Ahalapitiya H. Jayatissa
Keyword(s):  
Friction Coefficient ◽  
Coefficient Of Friction ◽  
Thermal Evaporation ◽  
Titanium Substrate ◽  
Water Film ◽  
Solid Lubricants ◽  
Thermal Evaporation Method ◽  
Practical Applications ◽  
Mos2 Film ◽  
The Coefficient Of Friction

MoS2 is one of the most advanced solid lubricants that have been used in many machineries. In this work, the effect of humidity on the friction of MoS2 solid film lubricant is investigated using a pin-on-disk tribometer. MoS2 film was coated by a thermal evaporation method on a titanium substrate. Steel and aluminum pins were used for the evaluation of friction coefficient of MoS2 films using a tribometer. The tests showed that with an increase in humidity, the coefficient of friction also increased. In practical applications at high humidity levels, the MoS2 films could be covered by condensed water molecules. Therefore, an experiment to understand the effect of water film on the variation of friction coefficient was also conducted. The results showed that the coefficient of friction remained constant for experiments using both aluminum and steel pins, and then the coefficient of friction increased once the water film was evaporated by the heat generated due to friction. An optical and XRD characterization of the MoS2 film was also conducted.

Experimental Study on Friction of Steel Wires of Dynamic Umbilical for Fatigue Life Analysis

2019 ◽  
Author(s):  
Yuanchao Yin ◽  
Qingzhen Lu ◽  
Shanghua Wu ◽  
Jun Yan ◽  
Qianjin Yue ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Coefficient Of Friction ◽  
Fatigue Behavior ◽  
Steel Wire ◽  
Friction Stress ◽  
Steel Wires ◽  
Stress Changes ◽  
The Coefficient Of Friction ◽  
Life Analysis ◽  
Fatigue Life Analysis

Abstract Dynamic umbilicals are widely used in the wet tree development of deep-water field. In the application of dynamic umbilicals, fatigue is a key failure mode which may cause severe economic consequences. The fatigue behavior of dynamic umbilical is complicated by the mechanical properties of the material, the cross-section design and the interaction of different components. Published studies have shown that the interaction friction stress of steel wires is critical for fatigue analysis. Coefficient of friction were used as a constant during the fatigue life analysis. However, the friction stress and the coefficient of friction may change during the wear of the steel wire. This paper presents a new experiment method and device to evaluate the change of the coefficient of friction of steel wire. Different cycles of reciprocating wear were carried out on samples to simulate interaction of the steel wires during the process of fatigue. The samples are pairs of steel wires which were cut on a dynamic umbilical. The interaction stress and friction stress were measured during the test. Micro morphology on the surface of steel wire at the contract zone were measured to investigate the wear of the sample. The test result shows that the coefficient of friction and stress changes during the test. Worn marks were found on the contact zone of the steel wires. The change of the coefficient of friction may affect the accuracy of fatigue life analysis of dynamic umbilical. Conclusions were also presented on the coefficient of friction test and theoretical calculation method to approach a more accurate fatigue life for dynamic umbilical design.

scholarly journals Iron’s Wake: The Performance of Quantum Mechanical-Derived Versus General-Purpose Force Fields Tested on a Luminescent Iron Complex

Molecules ◽  
2020 ◽  
Vol 25 (13) ◽  
pp. 3084 ◽  
Author(s):  
Valentin Diez-Cabanes ◽  
Giacomo Prampolini ◽  
Antonio Francés-Monerris ◽  
Antonio Monari ◽  
Mariachiara Pastore
Keyword(s):  
Force Fields ◽  
Low Cost ◽  
Md Simulations ◽  
General Purpose ◽  
Iron Complex ◽  
Chemical Environment ◽  
Quantum Mechanical ◽  
Minor Role ◽  
Transient Spectroscopy ◽  
A Minor

Recently synthetized iron complexes have achieved long-lived excited states and stabilities which are comparable, or even superior, to their ruthenium analogues, thus representing an eco-friendly and cheaper alternative to those materials based on rare metals. Most of computational tools which could help unravel the origin of this large efficiency rely on ab-initio methods which are not able, however, to capture the nanosecond time scale underlying these photophysical processes and the influence of their realistic environment. Therefore, it exists an urgent need of developing new low-cost, but still accurate enough, computational methodologies capable to deal with the steady-state and transient spectroscopy of transition metal complexes in solution. Following this idea, here we focus on the comparison between general-purpose transferable force-fields (FFs), directly available from existing databases, and specific quantum mechanical derived FFs (QMD-FFs), obtained in this work through the Joyce procedure. We have chosen a recently reported FeIII complex with nanosecond excited-state lifetime as a representative case. Our molecular dynamics (MD) simulations demonstrated that the QMD-FF nicely reproduces the structure and the dynamics of the complex and its chemical environment within the same precision as higher cost QM methods, whereas general-purpose FFs failed in this purpose. Although in this particular case the chemical environment plays a minor role on the photo physics of this system, these results highlight the potential of QMD-FFs to rationalize photophysical phenomena provided an accurate QM method to derive its parameters is chosen.

The Effect of Path Length and Display Size on Memory for Spatial Information

2012 ◽  
Vol 59 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Katherine Guérard ◽  
Sébastien Tremblay
Keyword(s):  
Path Length ◽  
Potential Role ◽  
Spatial Information ◽  
Recall Performance ◽  
Minor Role ◽  
Length Effect ◽  
Serial Memory ◽  
Fixed Reference ◽  
A Minor

In serial memory for spatial information, some studies showed that recall performance suffers when the distance between successive locations increases relatively to the size of the display in which they are presented (the path length effect; e.g., Parmentier et al., 2005) but not when distance is increased by enlarging the size of the display (e.g., Smyth & Scholey, 1994). In the present study, we examined the effect of varying the absolute and relative distance between to-be-remembered items on memory for spatial information. We manipulated path length using small (15″) and large (64″) screens within the same design. In two experiments, we showed that distance was disruptive mainly when it is varied relatively to a fixed reference frame, though increasing the size of the display also had a small deleterious effect on recall. The insertion of a retention interval did not influence these effects, suggesting that rehearsal plays a minor role in mediating the effects of distance on serial spatial memory. We discuss the potential role of perceptual organization in light of the pattern of results.

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