Effect Of Extreme Pressure Additives Research Articles

Effect of Extreme Pressure Additives on the Deformation Behavior of Oxide Scale during the Hot Rolling of Ferritic Stainless Steel Strips

High-speed steel (HSS) materials are universally used as work rolls for the hot rolling of stainless steels. Their use has increased the output of the rolling mill and decreased roll material consumption and grinding. Sticking defects often occur, however, during the hot rolling process. In this article, extreme pressure (EP) additives were dropped on the HSS samples at high temperature. Zinc dialkyl dithiophosphate (ZDDP) was chosen as the most effective EP additive by scratch tests on the HSS samples. In order to determine the optimum proportion of ZDDP in the lubricant, two reduction rates were tested on a Hille 100 experimental rolling mill by hot rolling ferritic stainless steel 445J1M at five different concentrations of ZDDP. The mechanism of EP additive action during the hot rolling process was also investigated. By analyzing the deformation behavior of the oxide scale of samples after hot rolling using different proportions of ZDDP, it was found that 20% ZDDP in the lubricant is the preferred concentration for industrial application.

Studies on Mirror Grinding of Aluminum Alloys by Traverse Grinding (1st Report) —Effect of Extreme Pressure Additives—

Studies on Mirror Grinding of Aluminum Alloys by Traverse Grinding (1st Report) —Effect of Extreme Pressure Additives—

Effects of Extreme Pressure Additives on Lubricity and Anti-seizure Property of Lubricants.

The effects on lubricity and anti-seizure property of lubricants according to base oils and EP additives of sulfur and phosphorous types in cold rolling were evaluated by a laboratory scale rolling mill, where the contact conditions between work roll and strip are very close to an actual cold rolling mill. The following experimental results were obtained. Sulfur type EP additive improves lubricity better than phosphorous type. In contrast, phosphorous type EP additive improves anti-seizure property better than sulfur type. And anti-seizure property is not affected by the kinds of base oil, but improved by the kinds and the amount of EP additives. Therefore, the amount of EP additives of sulfur and phosphorous types must be controlled in order to improve both lubricity and anti-seizure property. In addition, the existence of EP film was verified from the results of EDS analysis of the Falex test pins.

Evaluation of Scuffing Resistance of Grease-Lubricated Tapered Roller Bearings

An extensive lest program was conducted to evaluate the scuffing resistance of grease-lubricated tapered roller bearings. There were three main program objectives. 1. Provide validated and meaningful guidelines to designers on the speed capabilities of tapered roller bearings made with today's precision manufacturing practices. 2. Evaluate the effects of extreme-pressure additives on the scuffing resistance of these bearings. 3. Study the effects of extreme design conditions, which normally do not occur in practice, affecting the rib-roller and contact conditions on scuffing performance. Current grease-lubricated tapered roller bearings are found to perform, without the incidence of scuffing, at rib speeds of 15 to 20 m/sec. This is much higher than the values of 5 to 10 ml sec recommended. These lower values are based on the field knowledge and experience in the 1960s. Extreme-pressure (EP) additives provide no significant improvement in the speed capabilities of grease-lubricated tapered roller bearings...

The influence of grinding fluid on grinding ability (4th report, Action and effect of extreme pressure additives on working surface of diamond wheels in grinding)

The influence of grinding fluid on grinding ability (4th report, Action and effect of extreme pressure additives on working surface of diamond wheels in grinding)

Influence on grinding ability of grinding fluid (3rd report, Action and effect of extreme pressure additives on working surface of CBN wheels in grinding)

A study was made of the effect of extreme pressure additives in wet grinding of steels by CBN wheels. The findings are as follows, (1) The extreme pressure additive contained in the grinding fluid conducts the reaction to the CBN layer to produce the solid lubricating film (ferric chloride or ferric sulfide) on the cutting edge of CBN grains. (2) The formation of the solid lubricating film reduces the degree to which chips and ground metal are deposited on the cutting edge of CBN grains. (3) The amount of chips and ground meal deposited on the grain coating zone and the bond surface is reduced by the reaction of extreme pressure additives on the metal-coated grain, metal powder contained in the resinoid bond and the metal bond. (4) If the dilution is raised in applying the water base type grinding fluid, the degree of action of the extreme pressure additive to the CBN grain, bond, chip and metal deposit is lowered.

A method for studying the effect of extreme pressure additives on rubbing metal surfaces : Allan A. Manteuffel and George Wolfram. ASLE Trans., 3 (2) (1960) 157–164; 14 figs., 1 table, 5 refs

The influence of a boric additive on standard four-ball machine lubricating parameters of tricresylphosphate, zinc-dithiophosphate and sulphurized esters of fatty acids is studied. The consumption of active elements from the bulk oil of some of the samples is estimated by atomic emission spectrometry before and after a one hour wear test. This analysis can provide valuable information for additive and surface film studies. A considerable amount of tricresylphosphate or zinc dithiophosphate can be replaced by the boric additive in synergetic mixtures, without sacrificing lubricating properties. This opens up an opportunity for the formulation of additive packages with improved ecological compatibility.

A Method for Studying the Effect of Extreme Pressure Additives on Rubbing Metal Surfaces

When a film of lubricant separates two moving metal surfaces, it may be subjected to radical changes in temperature as the severity of the forces changes. This paper is concerned with a technique which measures the temperature of the lubricant after it leaves the area of rubbing metal surfaces. Special attention was given to: (A) the changing load conditions, (B) the changes in frictional force, (C) the effect of phosphate coating of the metal surface, and (D) the effect of different lubricant compositions. A modification of the Shell Four-ball EP Lubricant Tester has been made which permits automatic recording of a temperature-load curve which registers the temperature and frictional forces with either constant or changing load. The work has shown that as the load increases at a uniform rate, there may be drastic and sudden changes in lubricant temperature which depend on lubricant composition as well as on metal surface composition.