摘要:

AbstractSpindles experience problems related to increased power and velocity, and can have very high power consumption. The work reported here is aimed at improving design methods for high‐performance spindles and machine‐tool bearings, and is aimed at determining the influence, of the oil quantity supplying the contact, on power consumption and on contact temperature. A finite element program, TACT, can efficiently predict power loss and the thermal state of machine‐tool bearings, and the remaining unknown in these thermo‐piezo‐viscous‐elastic (TPVE) calculations is inlet oil film height. The authors address this problem and, within the context of this work, develop a high‐speed ISO 50 spindle which has a thin‐wall bearing housing, and is ‚thermally tuned‚, so avoiding thermal instability, while the preload stays constant. Its experimentally determined power consumption values agree well with the TPVE prediction for an assumed inlet fi

ISSN:1354-4063    

DOI:10.1002/tt.3020030302

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY

摘要:

AbstractA test method and a testing machine for evaluating the wear of lip seals for pneumatic cylinders are presented. The method and the machine have been evaluated with tests on different types of seals for cylinders with a 50 mm bore. Three levels of lubrication condition were examined: dry, with a film of grease, and with an optimum amount of grease. Differences were noted both between these conditions of lubrication, and between types of seal. © Leaf Coppin 1997

ISSN:1354-4063    

DOI:10.1002/tt.3020030303

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY

摘要:

AbstractAbrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two‐ and three‐body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the

ISSN:1354-4063    

DOI:10.1002/tt.3020030304

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY

摘要:

AbstractThis paper reports a three‐cylinder‐cone test configuration, which is claimed to be more appropriate to testing the tribological properties of surface hardened steels. Tests are run, for comparative purposes, against a Falex (pin and vee‐block) and Amsler (disc on disc) machines, and the results compared. For various plain carbon, low and medium‐alloy structural steels, nitrided and heat treated under various conditions, and for various test conditions, results are given for the three test methods and apparatus. An example is also given of laboratory simulation of a rubbing part in a hydraulic motor. © Leaf Cop

ISSN:1354-4063    

DOI:10.1002/tt.3020030305

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020030306

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020030307

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020030308

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020030301

出版商:John Wiley&Sons, Ltd    

年代:1997

数据来源: WILEY