摘要:

The effect of a face coning on seal performance, especially energy losses as indicated by a torque, were studied by comparing torque, face temperature, leakage, and wear of a conventional, widely used flat-face seal with three coned-face seals. Experimental evaluation was performed at rotation speeds to 8000 rpm, with pressures to 2758 kPa (400 psig), using a petroleum-base turbine oil. Axial movement of the mating seal parts was recorded using a digital data acquisition system. The height of the convergent-type cone on the face of the tungsten carbide primary ring ranged from 0.51 μm (20 μin) to 5.6 μm (220 μin) over the 3.175-mm to 6.36-mm (0.125-in to 0.25-in) face width. The torque of the coned-face seal, balanced lo 76.3 percent, was an average 42 percent lower, the leakage eleven limes higher than that of the standard flat-face seal. Reducing the balance to 51.3 percent by decreasing the face width of the coned-face seal resulted in lowering the torque by an additional 44 percent and increasing the leakage 12 to 230 times, depending on the seal shaft speed. No measurable wear was observed on the face of the coned seals. All four seals operated in the stable region of the stability map.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D. C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981522

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

An electronic optical laser interferometer capable of resolving depth differences of as low as 30 Å and planar displacements of 6000 Å was constructed for the examination of surface profiles of bearing surfaces without physical contact. This instrument was used to determine topological chemical reactivity by applying a drop of dilute alcoholic hydrochloric acid and measuring the profile of the solid surface before and after application of this probe. It was found that scuffed bearing surfaces exposed to lubricants containing an organic chloride reacted much more slowly. In a separate series of experiments, a number of stainless steel plates were heated in a nitrogen atmosphere to different temperatures and their reactivity examined later at ambient temperature. The change of surface contour as a result of the probe reaction was found to follow an Arrhenius-type relation with respect to heat treatment temperature. This result could have implications on the scuffing mechanism.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D.C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981523

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Infrared emission spectra and related measurements were obtained from an operating ball/plate EHD sliding contact under a variety of operating conditions. In order to be able to compare the effect of the ball surface, some of the steel balls were coated with a thin layer of titanium nitride (TiN) by vapor deposition. Polyphenyl ether (5P4E) was used as the lubricant and 1 percent of 1,1,2-trichloroethane (TCE) as an additive with a high affinity for steel but a low affinity for TiN. TiN is chemically inert, but its thermal conductivity is lower than that of steel. Therefore, the overall temperatures with TiN-coated balls were higher. Nevertheless, no scuffing was observed with the coated balls under conditions giving rise to scuffing with the uncoated balls. Tractions were lower with the TiN-coated balls and with the steel balls when TCE was added to the 5P4E. These findings were found to be inversely related to the degree of polarization of the spectral emission bands. The intensity and the dichroism of these bands were related to shear rates and inlet conditions of the EHD contact.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D.C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981524

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Recent additions to and modifications of automobile engines have significantly increased engine operating temperatures. There is concern about the effect of temperature increases on engine wear, but little, other than watching for the appearance of field problems has been reported. The effect of viscosity on wear was eliminated in this study by keeping viscosity constant while varying temperature. Under conditions which simulate valve train contact, it was found that wear increased approximately 3-fold over the temperature range 50° to 116°C. This increased wear, coupled with decreased viscosity with increasing temperature, leads to a potentially serious wear environment. Analysis of the data and comparison with possible mechanisms indicate that equilibrium adsorption of the antiwear additive is the controlling step in wear protection. Direct reaction of the antiwear additive with the surface at the higher temperatures had little, if any, contribution toward wear protection.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D.C., October 5–7, 1982.

ISSN:0569-8197    

DOI:10.1080/05698198308981525

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Wear studies were conducted in the chamber of a scanning electron microscope (SEM) to permit direct observations of the wear processes. The sliding specimens had been metallographically polished and etched prior to test so that the effect of the alloy micro-structures could be observed. Test alloys included: low and high carbon steels, stainless steels, and bronze. As wear particles were generated, and became trapped in the interface, they produced surface damage which was in the form of material removed, or metal transfer to one of the sliding members. Video tape records were made at magnification up to 8000X and photomicrographs were taken at higher magnification to show the geometry of the wear particles.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D.C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981526

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Titanium, argon, nitrogen, and iron were implanted in separate strips on a ferritic AISI E52100 cylinder. Three implant energies were chosen to obtain a continuous distribution from the surface to a depth of 120 nm and total doses were 4.1017ions cm−2. The friction coefficient and wear track topography were measured by sliding against a martensitic AISI 52100 steel ball in air, in a fully formulated lubricant and in highly purified hexadecane. In dry sliding, titanium reduced the friction coefficient to 0.32 and suppressed the near-surface cracking, [in agreement with previous work at Harwell and Naval Research Labs]. In hexadecane, titanium reduced the friction coefficient to 0.22, iron and nitrogen increased, it to 0.7 from 0.55, and all implants decreased wear. In the fully formulated lubricant, only the break-in pattern was modified. Auger measurements showed that carbon penetrated the material with all implants, creating TiC in the Ti-implanted strip and probably strengthening the other implanted areas by carbide precipitates and compressive stresses.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D.C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981527

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The rotor bearing running torque levels of certain spin bearing units were found to increase significantly during extended life testing. Samples of the greases from these tests were analyzed to determine if lubricant degradation was linked with the increased torque levels. By means of chromatographic and spectroscopic techniques, we were able to determine that oxidation of some of the greases had occurred and that the oxidative degradation was most easily observed in the soap-thickener portion of the grease. A correlation between the disappearance of the fatty acid salts and the appearance of degradation products was observed. Polymerization of the greases war observed in all samples. We also determined that the grease degradation was symptom of adverse mechanical condition in the bearings and not the primary cause of mechanical problems.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D.C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981528

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

This paper describes an investigation of the static contact between a steel ball and a lead-plated steel flat. Both the normal approach of the surfaces and their area of contact have been measured as functions of normal load and the thickness of the lead film. It is shown that, at high loads where the radius of contact is greater than five times the film thickness, all the coated surfaces behaved elastically, and the elastic properties of the coated surfaces were identical to those of the uncoated steel. At lower loads and high film thicknesses, the films deform plastically. The transition from elastic to plastic deformation occurred when the radius of the contact area was approximately five times the film thickness.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D. C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981529

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

A ball-bearing simulator was designed and constructed at our laboratories. This simulator replicates the essential features of a ball bearing, and allows for a variety of cage materials and solid film lubricants to be evaluated under simulated operating conditions. The geometry employed consists of a bearing ball sandwiched between two rotating inner-bearing races, and various levels of ball-race slip are imparted by changing the speed difference between the two races.

ISSN:0569-8197    

DOI:10.1080/05698198308981530

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Polymeric composite block samples were run dry against rotating stainless steel rings in a Falex Model No. 1 friction and wear test machine. An infrared fiber optics thermal monitor was used to measure temperatures on the block. A finite element heat-transfer analysis was used to predict the amount of heat transferred to the block and the rotating ring. In the finite element analysis, temperatures were specified on the contact surface and iterated until the computed temperature distributions away from the interface matched those measured to within 10 percent. Computed temperatures at the interface were 10–15 percent higher than those measured in proximity to, but not at, the interface. Block thermal conductivities ranged from 0.20 to 0.90 w/m-K, with the portion of heat transferred to the block varying proportionally and maximum block temperature varying inversely with block thermal conductivity. These effect are as expected from closed-form solutions assuming equal temperatures on either side of the interface.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D.C., October 5–7, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981531

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor