| 1. |
- Kumar, Rajesh, et al.
(författare)
-
Assessment of engine liner wear from bearing area curves
- 2000
-
Ingår i: Wear. - 0043-1648 .- 1873-2577. ; 239:2, s. 282-286
-
Tidskriftsartikel (refereegranskat)abstract
- This paper proposes a new procedure to evaluate engine liner wear volume and wear depth particularly for short duration engine tests. The method is based on the fact that honing depth is not removed when small amount of wear occurs. It was considered that 90% point of the bearing area curve is the same before and after wear. Then, the bearing area curve for the used liner was transformed by the depth differences at 90% and the area between the two curves was calculated by numerical procedure. As the diameter of the liner is known, the wear volume was calculated for the various zones selected at different points from TDC and BDC. The methodology involved has been programmed in C++. The wear depth is obtained by the projection on the depth axis of the two bearing area curves, and then finding their difference. This method is considered superior to the usual method of gauging the changes in diameter as such determinations are influenced by the distortions that occur in the liner. The new procedure needs to be applied more extensively to improve confidence in repeatability and reproducibility and to determine the limits of applicability. Controlled laboratory wear tests and further measurements on cylinders from field engines are therefore proposed.
|
|
| 2. |
- Mann, B. S., et al.
(författare)
-
High temperature friction and wear characteristics of various coating materials for steam valve spindle application
- 2000
-
Ingår i: Wear. - 0043-1648 .- 1873-2577. ; 240:1-2, s. 223-230
-
Tidskriftsartikel (refereegranskat)abstract
- Various coatings such as chromium carbide (deposited by plasma spraying and detonation gun techniques), chromium oxide, chromium oxide + titania + silica, NiCrAlY, and Al2O3 + Ni all deposited by plasma spraying; stelliting, and surface nitriding have been applied on X20CrMo V121 steel. This steel is used for high temperature applications such as steam turbine valve spindle. Friction and wear behavior of the surface coated and treated materials have been studied at an elevated temperature of 550°C while rubbing against graphite-filled stellited steel. These studies have been carried out on SRV optimol reciprocating tribometer. Test parameters for tribological studies have been selected with a view to simulate operating conditions encountered in operation. Additionally, the structure, porosity, hardness, bond strength, and thermal cycling behaviour of these surface coated/treated materials have been characterised. Based on these laboratory investigations, chromium carbide coating deposited by plasma spraying technique has been identified as the most suitable coating for steam turbine valve spindle application. Process parameters have been established for deposition of chromium carbide coating by plasma spraying technique on actual valve spindles. The field results obtained are found to be commensurate with the laboratory findings.
|
|
| 3. |
|
|
| 4. |
- Prakash, Braham, et al.
(författare)
-
Sliding wear behaviour of some Fe, Co and Ni based metallic glasses while rubbing against bearing steel
- 2000
-
Ingår i: Tribology letters. - 1023-8883 .- 1573-2711. ; 2-3, s. 153-160
-
Tidskriftsartikel (refereegranskat)abstract
- The sliding wear behaviour of several compositions of Fe-, Co- and Ni-based metallic glasses have been studied while rubbing against AISI 52100 bearing steel under reciprocating-sliding conditions. The wear resistances of Fe-based metallic glasses and Ni-based metallic glass (MBF 50) have been found to be superior to that of the mating AISI 52100 bearing steel. The examination of worn surfaces indicates that the superior wear resistance of metallic glasses is not merely owing to their high hardness but it is determined by phenomena of material transfer vis-à-vis the mating material and the formation of protective oxide layers on the metallic-glass surface during sliding.
|
|
