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Title: The Development of a Pin-on-Twin Scuffing Test to Evaluate Materials for Heavy Duty Diesel Fuel Injectors

Abstract

In order to meet stricter emissions requirements, advanced heavy-duty diesel fuel injection systems will be required to operate at higher pressures and temperatures and in fuels that have poorer lubricity. Scuffing, as a mode of failure, severely limits injector life, and new materials and processes are required to resist scuffing in these more stringent operating conditions. Consequently, there is a need to test the ability of candidate fuel system materials to resist scuffing in fuel-lubricated environments. This paper describes a pin-on-twin reciprocating wear test in which a cylindrical specimen slides, under load, across two fixed, parallel cylindrical specimens that are perpendicular to the axis of the upper sliding specimen. Cylinders of annealed AISI 52100 were tested dry and lubricated by Jet A fuel and on-highway no. 2 diesel fuel. The friction force was found to give a reliable real-time determination of the onset of scuffing as verified by the morphology of the wear scar. The scar width and surface roughness profiles either did not reliably detect the onset or were difficult to carry out with this geometry.

Authors:
 [1];  [1];  [2];  [1]
  1. ORNL
  2. Caterpillar Inc.
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
931339
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Tribology Transactions; Journal Volume: 50; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
33 ADVANCED PROPULSION SYSTEMS; DIESEL FUELS; FRICTION; FUEL SYSTEMS; GEOMETRY; MORPHOLOGY; ROUGHNESS; FUEL INJECTION SYSTEMS

Citation Formats

Qu, Jun, Blau, Peter Julian, Truhan, John J., and Ott, Ronald D. The Development of a Pin-on-Twin Scuffing Test to Evaluate Materials for Heavy Duty Diesel Fuel Injectors. United States: N. p., 2007. Web. doi:10.1080/10402000600943883.
Qu, Jun, Blau, Peter Julian, Truhan, John J., & Ott, Ronald D. The Development of a Pin-on-Twin Scuffing Test to Evaluate Materials for Heavy Duty Diesel Fuel Injectors. United States. doi:10.1080/10402000600943883.
Qu, Jun, Blau, Peter Julian, Truhan, John J., and Ott, Ronald D. Mon . "The Development of a Pin-on-Twin Scuffing Test to Evaluate Materials for Heavy Duty Diesel Fuel Injectors". United States. doi:10.1080/10402000600943883.
@article{osti_931339,
title = {The Development of a Pin-on-Twin Scuffing Test to Evaluate Materials for Heavy Duty Diesel Fuel Injectors},
author = {Qu, Jun and Blau, Peter Julian and Truhan, John J. and Ott, Ronald D},
abstractNote = {In order to meet stricter emissions requirements, advanced heavy-duty diesel fuel injection systems will be required to operate at higher pressures and temperatures and in fuels that have poorer lubricity. Scuffing, as a mode of failure, severely limits injector life, and new materials and processes are required to resist scuffing in these more stringent operating conditions. Consequently, there is a need to test the ability of candidate fuel system materials to resist scuffing in fuel-lubricated environments. This paper describes a pin-on-twin reciprocating wear test in which a cylindrical specimen slides, under load, across two fixed, parallel cylindrical specimens that are perpendicular to the axis of the upper sliding specimen. Cylinders of annealed AISI 52100 were tested dry and lubricated by Jet A fuel and on-highway no. 2 diesel fuel. The friction force was found to give a reliable real-time determination of the onset of scuffing as verified by the morphology of the wear scar. The scar width and surface roughness profiles either did not reliably detect the onset or were difficult to carry out with this geometry.},
doi = {10.1080/10402000600943883},
journal = {Tribology Transactions},
number = 1,
volume = 50,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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