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Metalworking fluids are applied in metal working operations in order to decrease tribological effects and increase economy. Primarily they are used for cooling the tools…
Metalworking fluids are applied in metal working operations in order to decrease tribological effects and increase economy. Primarily they are used for cooling the tools and the workpieces and also for lubricating the cutting edges. The components of metalworking fluids responsible for decrease in friction are AW/EP additives. To comply with the very strong European legislation for human and environmental protection, important compounds for metalworking fluids formulation are reduced. Based on this, chlorinated paraffin, a widely used AW/EP additive, should be replaced with less harmful compounds. The application possibility of new types of AW/EP additives as chlorinated paraffin replacements is investigated in this paper. These additives are synthetic esters of carboxylic fatty acids, phosphoric and dithiophosphoric acid derivatives. Watermiscible metalworking fluids formulations are prepared with the new types of additives and examined at laboratory test machines–EP‐Four ball, Wear‐Four ball machine and Reichert balance machine.
Metalworking fluids can significantly increase the tool life in titanium cutting, however, full-scale cutting tests to determine the performance of metalworking fluid are…
Metalworking fluids can significantly increase the tool life in titanium cutting, however, full-scale cutting tests to determine the performance of metalworking fluid are expensive. The aim of this study is therefore to introduce a reliable and inexpensive alternative testing method.
A newly developed in-process tribometer allows emulating the sliding conditions of the chip formed in cutting as closely as possible. It uses a cutting action in front of a pin to eliminate the influence of the oxidation layer. To observe the wear pattern on the pin, adhering workpiece material is removed by selective etching. A high temperature oxidation test is used to study the wear mechanism.
The wear pattern on the pin correlates well with the wear pattern observed on cutting tools when using the same metalworking fluid while being much more cost-effective than a tool life test. The high temperature oxidation test reveals that cobalt leaching is causing notch wear.
The correlation between pin and tool wear is verified for the case of roughing turning of titanium with cemented carbide tools and two metalworking fluids.
The method is applicable in an industrial context, potentially replacing the currently used tribological analyzes.
Submitted in connection with the special issue “young tribologists – insights into the work of the new generation”.
Methods tailored to model the tool wear in titanium cutting are rare. For the first time, an in-process tribometer, which is especially suited for the analysis of titanium cutting, is used to assess the wear behavior. The design of the high temperature oxidation test is new.
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0311
Boundary layers, which develop during manufacturing and operation, can protect tooth flanks from metal-to-metal contacts. The characteristics of boundary layers and the…
Boundary layers, which develop during manufacturing and operation, can protect tooth flanks from metal-to-metal contacts. The characteristics of boundary layers and the running behavior of gears are determined by the preconditioning processes (manufacturing and run-in). This paper aims to analyze the influence of the grinding process parameters and the grinding oil on the characteristics of boundary layers.
Sets of test parts and test gear sets with different grinding process variants and different metalworking fluids were manufactured to investigate the mechanisms of action of thermomechanical and chemical surface preconditioning during grinding. The test parts were analyzed with regard to their boundary layer by metallography and chemistry and regarding their running behavior on test rigs lubricated with transmission oil.
In the tests, reproducible differences in gear strength regarding low-cycle fatigue and micropitting were determined for the test parts ground with different thermomechanical energy inputs and with different metalworking fluids. As the test results could not be sufficiently explained on the basis of conventionally tolerated component properties such as roughness, hardness and residual stresses, a model was discussed which combines the mechanisms of action of the formation of the manufacturing-induced boundary layer with the running behavior of the parts.
By combining both measurement and test results, possible correlations between manufacturing and operation are investigated to establish a more sustainable and economical design of gears.
Some of the mechanisms involved in the microbial colonisation and biodeterioration of metalworking fluids are described in an attempt to design a more realistic and…
Some of the mechanisms involved in the microbial colonisation and biodeterioration of metalworking fluids are described in an attempt to design a more realistic and meaningful laboratory assay procedure. The history of bioassay techniques is reviewed and the nature and composition of metalworking fluids is examined. Maximisation of the performance of biocides against micro‐organisms and the influence of tramp oil contamination is assessed.
Manufacturers increasingly seek new ways to add customer value and differentiate. However, in business markets such efforts often remain relatively unsuccessful, leading…
Manufacturers increasingly seek new ways to add customer value and differentiate. However, in business markets such efforts often remain relatively unsuccessful, leading to a large number of services offered and higher costs, but with limited corresponding returns. Based on extensive expert interviews and case study research, this paper studies how suppliers in the highly commoditized metalworking industry try to realize new types of customer value. The paper identifies “ideal” value positions pursued by Belgian contract manufacturers and service providers in order to survive in an industry characterized by fierce price competition from low labor cost countries. Further, the paper shows how companies can migrate to these “ideal” value offerings. Key success factors and potential traps for each ideal type are identified. Market strategy transition necessitates an internal “alignment” strategy and an external “coevolution” with chain partners.
No one particular fluid has cooling and lubrication properties suitable for every metalworking application. The purpose of this paper is first, to investigate the effect…
No one particular fluid has cooling and lubrication properties suitable for every metalworking application. The purpose of this paper is first, to investigate the effect of anionic and nonionic mixed emulsifier system in stabilization of cutting fluid formulations and second, to study the interaction synergism of the fulfill additives of metalworking fluids to achieve low scar diameters, high stability, anti rusting and corrosion properties.
A lot of set mixtures in this work were formulated to get the demand needed for soluble oil metalworking fluids. It was based on a blend of emulsifier package (anionic‐non ionic), and in order to reach acceptable manufacturing conditions, coupling agent, stabilizer, biocide, base oil and anti‐rust additives were added to the formulation. Different percentages of these components were incorporated to optimize the stability of the emulsifier system. Standard tests were carried out to evaluate the performance of oil‐in‐water (O/W) emulsions as lubricating and cooling fluids in machining operations. The evaluation was drawn in five factors; oil stability, emulsion stability, pH, anti‐rust (corrosion inhibition), biological activity and extreme pressure performance tests.
All tests achieved excellent results according to the ASTM. From the obtained results, the formula (named EPRI 950) exhibited a good performance compared with the commercial cutting fluid.
This work investigates the effect of anionic and nonionic mixed emulsifier system in stabilization of cutting fluid formulations; and the interaction synergism of the fulfill additives of metalworking fluids to achieve low scar diameters, high stability, anti‐rusting and corrosion properties.
The West European metalworking lubricants market has seen a number of major changes in the past decade.
This article examines the relationship between German trade unions and works councils, adopting a framework that identifies three main influences on the works council; the…
This article examines the relationship between German trade unions and works councils, adopting a framework that identifies three main influences on the works council; the locus of bargaining, economic conditions and the strength of workplace unionism. The findings of an attitudinal survey of works council chairpersons in the metalworking industry, which examines both the influence of trade unions and the impact of unification on workplace industrial relations, are then reported. The results suggest that union density and union workplace organisation does strengthen the loyalty of works councillors to their union and that east German works councillors in metalworking may have more co‐operative relationships with management. Comparisons with the clothing industry, however, show larger sectoral differences, with metalworking works councils much less co‐operative in both the old and new Länder, reflecting the vanguard role of IG Metall and the importance of workplace mobilisation to the union.