摘要:

A new device has been developed and used to study metallic contact and friction between sliding, lubricated surfaces. The system consists basically of a fixed metal ball loaded against a rotating cylinder. The extent of metallic contact is determined by measuring both the instantaneous and average electrical resistance between the two surfaces. Friction between the ball and cylinder is recorded simultaneously with contact.

ISSN:0569-8197    

DOI:10.1080/05698196108972414

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

This paper describes an experimental investigation of materials for use as high temperature rubbing seals.

ISSN:0569-8197    

DOI:10.1080/05698196108972415

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Apparatus is described for measuring friction and wear in controlled atmospheres. A comparison is made of the room temperature behavior of copper, mild steel and brass, rubbed against a hardened tool steel, in four environments—vacuum (10−3mm Hg), dry helium, dry carbon dioxide, and dry air. The effect of varying the water vapor content in air is also discussed.

ISSN:0569-8197    

DOI:10.1080/05698196108972416

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Various gases were used as corrosion inhibitors for nickel- and cobalt-base alloys in halogen-containing gas lubrication systems. Corrosion experiments were conducted at 1500 F with CF2Cl2and various mixtures of gas with inhibitors. One gas found to be a satisfactory inhibitor was air (oxygen). Oxygen reacted at the metal surface in competition with the chlorine of CF2Cl2, thus reducing corrosion. Friction and wear experiments conducted with a CF2Cl2-air mixture lubricating Al2O3sliding on cobalt base alloy showed low wear and low friction over the temperature range from 75 to 1500 F.*Presented as an American Society of Lubrication Engineers paper at the Lubrication Conference held in Boston, Massachusetts, October 17–19, 1960.

ISSN:0569-8197    

DOI:10.1080/05698196108972417

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Life tests on ball bearings running at 100 rpm without lubrication in hot gaseous environments under thrust loads show that their performance, worse than when running under lubricated conditions, is significantly affected by the environment. Two gases, nitrogen and carbon dioxide, are considered. In nitrogen, at temperatures of 200 C and 250 C, the load-carrying capacity was only some 2% of the capacity for lubricated operation at normal temperature, the best results being obtained with full type, cageless, angular contact bearings. In carbon dioxide, however, at 325 C and 375 C, loads of up to 30% of the lubricated capacity were achieved with deep groove, caged bearings. Similar bearings in a 16% Cr stainless steel performed even better at up to 50% of the lubricated capacity.

ISSN:0569-8197    

DOI:10.1080/05698196108972418

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

The demand for the reliable operation of rotating machinery in cryogenic applications has resulted in a continuing program directed toward determining the life and durability of ball bearings operating at cryogenic temperatures. On the basis of past work in this field, it was determined that the ball separator, when made from conventional materials, usually was the cause of failure. A program of screening separator materials with bearings subjected to actual operating conditions was undertaken. A number of different separator materials and arrangements were tested to determine their relative durability. The apparatus used provided a method of loading the bearing axially and included a means of measuring bearing torque, wear, and load during operation. All of the tests of this screening program were conducted using liquid nitrogen. The results are presented in the form of bearing life, progressive bearing torque, and progressive bearing wear for the various configurations and types of separator materials tested. Photographs showing the test apparatus and some test bearings are included in addition to a graphic presentation of the test results. This test program proved that a ball separator made from filled polytetrafluoroethylene material3is superior to the other separator materials tested in liquid nitrogen.*Presented as an American Society of Lubrication Engineers paper at the Lubrication Conference held in Boston, Massachusetts, October 17–19, 1960.

ISSN:0569-8197    

DOI:10.1080/05698196108972419

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

In a gear contact as simulated on a roller test machine, the instantaneous coefficient of friction follows the concept of transition from boundary to hydrodynamic lubrication. The coefficient has been found to increase with increasing load and to decrease with increasing sum velocity, sliding velocity, and oil viscosity as each of these quantities is varied individually. The viscosity was determined by the temperature of the oil entering contact and the viscosity-temperature characteristics of the lubricant. The results have been combined in a formula which closely represents the data. When this formula is used in gear scoring calculations, the same type of U-shaped load-speed curve is obtained as has been found on several gear test rigs.*Presented as an American Society of Lubrication Engineers paper at the Lubrication Conference held in Boston, Massachusetts, October 17–19, 1960.

ISSN:0569-8197    

DOI:10.1080/05698196108972420

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

The FZG test is a usual and standardized method in West Germany to evaluate the antiscuffing properties of oils for reduction gears, hypoid gears, automatic transmission gears, etc. The paper gives a brief survey of the test apparatus, the test gears, and the test procedure. It describes also the criteria of failure and the evaluation of the results, taking into account not only the load-carrying capacity but also the wear performance of an oil. The repeatability and the scattering range is discussed with respect to the test conditions. The field of application for standardized gear rigs is pointed out. This is followed by a discussion of results showing the effect of tooth profile, mineral and synthetic oils, pitch line velocity, temperature, and surface treatment on the load-carrying capacity.

ISSN:0569-8197    

DOI:10.1080/05698196108972421

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

The interactions of five gases (helium, hydrogen, nitrogen, argon, and carbon dioxide) with mineral and synthetic lubricating oils were studied. The interactions examined included gas solubility, foaming, entrainment, evaporation of oil into gas, stability of oil in presence of gas, and effect of dissolved gas an oil viscosity. Several of the gases showed behavior (appreciably different from that of air) that was not predicted by conventional theories. No important differences were found between mineral and synthetic (diester) oils in these respects. The additives used can have appreciable influence on the foaming and entrainment characteristics, and evaporation rates, of both types of oils.*Presented as an American Society of Lubrication Engineers paper at the Lubrication Conference held in Boston, Massachusetts, October 17–19, 1960.

ISSN:0569-8197    

DOI:10.1080/05698196108972422

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

This paper investigates the effect of lubricant composition on engine friction and connecting-rod bearing wear. Special attention has been given to polymer-thickened (VI improved) oils since these oils are characterized by shear-dependent viscosity and a simultaneous occurrence of viscous and elastic properties. The variables investigated in this study included lubricant viscosity, polymer type, and concentration.

ISSN:0569-8197    

DOI:10.1080/05698196108972423

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor