Industrial Lubrication and Tribology

P.S. Mukherjee; A.M. Sinha; A. De

2000 Industrial Lubrication and Tribology

doi: 10.1108/00368790010317348

Scheduled rejection of lubricants in central lubrication systems often leads to loss of lubricants as these could be used for a further long period. To avoid such loss, periodic monitoring of lubricants is suggested so as to forecast the time when the lubricant in a particular system of equipment loses its properties and requires to be drained‐off and charged afresh. To assess the remaining useful life of lubricant (RULL) in use, a new method by fourier transform infrared (FTIR) spectroscopy is used. The work is supplemented by a case study on heavy earth moving machinery (HEMM) deployed in Indian mines.

B.B. Ahuj; P.P. Chikate; S.K. Basu

2000 Industrial Lubrication and Tribology

doi: 10.1108/00368790010317357

Deals with the development of aerostatic‐cum‐aerodynamic hybrid conical bearings, running at 70,000 r.p.m., suitable for supports of high speed spindles. Conical bearing bush is designed for two plane admission, with eight holes in each plane, with a semi cone angle of 108. In case of static response, the interactions between the major parameters, are projected on 3D response surface curve. The results give the magnitude of radial load to get the benefit of optimally minimum eccentricity ratio. Experimental results show close agreement with the theoretical work in regard to “no‐rotation” cases. The exponential relationship existing between eccentricity ratio, radial load and supply pressure is generalised. Rigidity for the bearings developed, as seen from the response surface, supports the observations of previous researchers. For the use of designers, vital operational parameters have been tabulated. Estimated and experimental values of these parameters compare reasonably.

Jan Lundberg; Sven Berg

2000 Industrial Lubrication and Tribology

doi: 10.1108/00368790010317366

New, undestroyed greases of the same brands as those used in a field test, described in Part 1, were examined using conventional methods, such as the SKF V2F test, the roll stability test (ASTM D‐1831), the Grease Worker (ASTM D‐217), the torque test (ASTM 1478‐91), bleeding measurements ( IP 121), yield stress measurements, the 4‐ball test (ASTM D 2266‐86), base oil viscosity measurements, thickener content and the cone penetration test (ASTM D217‐88). The greases have also been tested with several new test methods developed at the University. A specification for relevant testing methods was drawn up and the connections between the tested parameters were investigated. It was found that the mechanical stability could be predicted with a combination of ASTM D‐1831 and the limiting shear stress coefficient े. This coefficient is capable of predicting wear. It was found that the bearing temperature could be predicted by using the base oil viscosity.