Click here to make tpub.com your Home Page

Page Title: Section II: NONAERONAUTICAL EQUIPMENT ANALYTICAL METHODOLOGY
Back | Up | Next

Click here for thousands of PDF manuals

Google


Web
www.tpub.com

Home


   
Information Categories
.... Administration
Advancement
Aerographer
Automotive
Aviation
Construction
Diving
Draftsman
Engineering
Electronics
Food and Cooking
Logistics
Math
Medical
Music
Nuclear Fundamentals
Photography
Religion
   
   

 

NAVAIR 17-15-50.4
TM 38-301-4
T.O. 33-1-37-4
CGTO 33-1-37-4
NONAERONAUTICAL EQUIPMENT ANALYTICAL METHODOLOGY
2-1. General.
a.  Each moving part in a machine has a normal rate of wear. As machine components wear, microscopic
metallic wear particles are generated. Some microscopic particles are small enough to pass through a filter and
remain suspended in the lubricating oil. When a machine is operating normally and operated under normal
conditions, the concentration of these wear particles will be fairly consistent at the end of each oil change period.
However, differences in load and working environment will affect the rate of wear of the machine components, as
will various internal oil system problems and component friction changes. When abnormal wear takes place in the
equipment, the concentration of one or more elements will increase significantly. Therefore, the concentration of
wear particles will not always be the same and the evaluator must interpret the results of oil sample analysis to
determine the reason for the changes detected and the possible effects of these changes on the equipment.
b.  The JOAP nonaeronautical analytical methodology encompasses the interpretation of used oil sample
analysis results, assessment of equipment and oil condition based on analysis results, diagnosis of the probable
sources of wear-metals and contaminants, and the issuance of accurate and effective equipment maintenance
and operational recommendations to the operating activity. The methodology uses wear-metal evaluation criteria
tables by type equipment and individual equipment diagrams (Appendix B and D) as well as subjective evaluation
of a series of laboratory test.
(1)  The wear-metal evaluation criteria tables provide the wear-metal range and trend values which
relate the oil sample wear-metal concentration to the expected condition of the equipment or oil condition. These
tables also contain supplemental technical information to assist the evaluator in identifying the most probable
sources of wear-metal. For some equipment, the criteria have not been determined but will be added when
available. Data provided in these tables are intended for use as guidelines by evaluators, not as strict go/no-go
criteria. The guidelines were statistically derived using analysis of samples from operating equipment from
various geography locations. Absolute values that will indicate specific impending component failures may
actually be somewhat above or below the concentration levels shown. Therefore, the evaluator must apply
subjective judgement, experience, and knowledge of the particular component from which a sample is taken to
determine evaluation recommendations.
(2)  The individual equipment diagrams present wear-metals source information keyed to location by
the use of equipment cutaway schematics. The cutaway or cross sectional figures for the equipment provide
detailed breakout information of metallic elements present in the equipment. In some instances, the figures
identify elements that will not be detected by the spectrometer. These elements are shown for evaluator
information only, with the possibility that they may be detected by other laboratory methods. In cases where the
major element for a component is known, it is indicated by being shown first and underscored. Generally, the
combinations of elements shown are listed in descending order of the amounts present in the components.
NOTE
The Engine/Transmission/Equipment Cross Index listing in Appendix B includes a
cross index for nonaeronautical equipment items. The end items shown in the
appendix for a particular engine or transmission may not be the only equipment which
utilize that particular engine/transmission.
2-2. Wear-Metal Sources.
a.  Internal combustion engines are subject to contamination from external sources such as sand and dirt,
as well as internal sources, such as blow-by combustion contaminants and wear-metals from various oil-wetted
moving parts, which are deposited in the oil system in varying degrees, depending upon the equipment condition.

Privacy Statement - Press Release - Copyright Information. - Contact Us

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business