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New
Lubricant Evaluation and Acceptance
A Laboratory’s Perspective
Society of Tribologists and Lubrication Engineers
Annual Meeting Cincinnati Ohio May 1996
William R. Herguth, Herguth Laboratories, Inc. Vallejo, CA
Abstract
New product evaluation and acceptance is a process used to some extent
by all nuclear power plants in the United States. It certainly should
be a process embraced by all power plants as an integral part of their
total quality management. New product dedication is a process that
allows the recipient of products to use them with reasonable assurance
that they are, in fact, the products that were specified, purchased
and delivered. In the longer term, the benefits of a thoroughly documented
dedication process can negate contingent liability issues that may
arise only after the fact and produce maintenance savings in proper
evaluation of the used oil analysis results for machinery within the
plant. Knowing the lubricant characteristics of the original batch
will aid in the subsequent comparisons of oil, grease, and failures
in your condition monitoring program. Liability issues that come into
question (only after a problem occurs) about the original lubricant
grade, type or quality can be easily retrieved and reviewed by management
in order to resolve quality issues.
Background
Simple though it sounds, some plants have a difficult time following
the most basic steps in the management of their lubrication programs.
Beyond the basic specifying, purchasing and control of lubrication
oils and greases, there are a multitude of tasks that must be performed
when a quality lubrication management program is to be implemented.
This paper is limited to those activities which affect the delivery
of the correct products to the plant.
Stepping back for a moment, the question that must be answered before
any manager will spend time and money to implement an evaluation and
acceptance program that, on the surface, may not appear necessary
is, “What’s in it for the plant”? Depending on the
plant, there may be more at stake than a simple increase in a machines
wear rate due to dirty oil or the premature failure of a machine due
to the incorrect lubricant being used (as if that is not enough).
The mismanagement of lubricants could turn into a serious violation
of federal safety regulations, violate nuclear agency statutes, or
be the root cause for a major plant shutdown.
Identifying the critical characteristics of machine lubricant combinations
within your plant will no doubt quickly convince management of incoming
lubricant evaluation should be a part of your overall procurement,
quality and maintenance programs.
Lubrication Survey
In order to begin the process, machines requiring lubrication must
be listed in an organized fashion. This is normally called a “Lubrication
Survey.” A typical lubrication survey would include:
1. Machine Information
Machine Identification, Type, Service, Manufacturer and Model
Recommended Lubricant Type/Grade and Volume
Lubrication Frequency, Sampling Points and Methods
2. Lubricant Information
Procurement Specifications
Storage and Handling Procedures
3. Lubricant Evaluation and Acceptance
Potential Problems and Impact
Methods of Analysis
Acceptance Criteria
1. Machine Information
The first task is to develop documentation of the type of machine(s)
to be lubricated. This includes make, model, identification (name/number)
and some designation outlining the severity of service, such as, is
it continuously operated at temperatures above “X” or
is it operated in a wet or dusty environment? Once this is accomplished,
review the lubricant type and grade that is actually used in the machine,
comparing this information to the manufacturers recommended lubricant
for the machine/service combination. Any differences in the lubricant
used as compared to the recommended lubricant must be justified! In
practice never assume that the equipment manual is always correct.
When justifying any differences, discussing them with the engineering
group at the Original Equipment Manufacturer (OEM) may help.
Often recommendations found in manuals or sales literature for machine
lubricant combinations are outdated and/or the recommend lubricant
has changed without the change being noted. The volume of lubricant
used in the machine and the frequency of relubrication should be addressed
during this phase. It will be helpful later when purchasing and schedules
are being set and used oil analysis results need to be interpreted.
2. Lubricant Information
Once the machine portion of the lubricant survey is complete, a detailed
evaluation of all of the lubricants purchased must be undertaken.
This should include matching each lubricant purchased to the machine(s)
being lubricated. The type of packaging, minimum re-order points,
quantities, suppliers and alternatives should all be documented.
At this point, methods of handling including storage and distribution
throughout the plant should be documented. It will do no good to spend
time and effort performing any of these procedures if, when the products
are stored or distributed within the facility they are mishandled
by the introduction of contaminates, incorrectly introduced into the
wrong machine and in general not controlled.
3. Lubricant Evaluation and Acceptance
Potential problems that may be encountered with the various lubricants
used and the impact that off-specifications may have on operations
both need to be defined. Evaluation methods and acceptance criteria
will vary depending on the potential problems and the risk associated
with off-specification lubricants. The type of lubricant, age, packaging
and methods of distribution will all have an impact on what you might
expect to see if there were a problem.
When selecting analysis, the first determination that needs to be
considered is what level of
accuracy is required in the analysis. In general, there are three
different types of analysis available. They are Strict American Society
of Testing and Materials (ASTM) test methods, modified ASTM methods
or those tests developed in-house. Generally each level costs less.
But, along with that lower fee, comes some penalty for accuracy and
tractability.
There is no set rule for the use of any one level of analysis. Nuclear
dedication practices and bulk cargo transfers dictate the use of strict
ASTM. Obviously, this is due to the severity of potential problems
that may arise if the product is off-specification. While smaller
volumes of product or less critical applications may simply require
that the receipt inspection include matching labels and the quantity
delivered matches the purchase requisition. This issue is entirely
up to the plant, but the key is that it is documented and used.
Set evaluation and acceptance criteria based on:
a. Plant Maintenance Philosophy/Legal Obligations
b. Equipment Manufacturers’ Specifications
c. Lubricant Suppliers’ Specifications
d. Risk Assessment
e. Experience
Potential Problems:
a. Incorrect Product Delivered
b. Contamination
c. Unsatisfactory Chemical Physical Properties
Incorrect Product Delivered
The problem of the incorrect product being delivered should be the
easiest to solve. Educating the receiving group to be aware of the
lubricant types used in the plant and requiring them to simply document
that the lubricant ordered was, in fact received. This basic procedure
may apply (depending on your procedures) to small quantities of lubricant
designated exclusively for machines that if off-specification lubricants
were used would not involve risk(s) beyond the criteria set previously
in “Selection of Evaluation and Acceptance Criteria.”
It should be noted that even if the product labeling is acceptable
using this screening process, there is no guarantee that the lubricant
in the container is acceptable. In cases where it is necessary to
ensure that the actual product is satisfactory, other evaluations
criteria must be set. This basic screening process will be the same
regardless of the sophistication of any subsequent analysis for various
lubricant and machine combinations.
Elements of the initial screening include:
Product Labeling and Packaging
Product Description: ______________________________
Date of Manufacture: ___________ Lot # ____________
Date Received: ________________
Characteristic: Method Specification Actual Accepted
Company Visual Label “ABC Oil Company” ________________
Y or N
Product Name Visual Label “ Premium R&O 32” ________________
Y or N
Packaging Visual 5gal Drum ________________ Y or N
Quantity Ordered Count 1 Each ________________ Y or N
Approved by:______________________ Date: ________
Not Approved by: __________________ Date: ________
Explanation if Not Approved:
Contaminated Product Delivered
Contamination of new lubricants can be found in a variety of forms.
Generally they are water, debris, different lubricant, chemicals and
fuel products. The evaluation of possible contamination should be
relegated to those properties for which specific criteria can be applied
for acceptance or rejection. The more risk involved with the use of
off-specification product, the more sophisticated the analysis should
be. The evaluation may range from a simple visual examination of the
contents of a tube of grease or a drum of oil to laboratory analysis
using Viscosity, Fourier Transformed Infrared, Particle Counting or
a variety of methods. Once again, the depth of analysis needs to be
based on the risk to your operation.
Contamination Evaluation
Short Form Oil
Product Description: ______________________________
Date of Manufacture: ___________ Lot # ____________
Date Received: ________________
Characteristic: Method Specification Actual Accepted
Company Visual Label “ABC Oil Company” ________________
Y or N
Product Name Visual Label “ Premium R&O 32” ________________
Y or N
Packaging Visual 5gal Drum ________________ Y or N
Quantity Ordered Count 1 Each ________________ Y or N
Appearance Visual No Visible Debris ________________ Y or N
Color Visual Light Yellow ________________ Y or N
Clarity Visual Clear and Bright ________________ Y or N
Approved by:______________________ Date: ________
Not Approved by: __________________ Date: ________
Explanation if Not Approved:
Contamination Evaluation
Safety Related
Product Description: ______________________________
Date of Manufacture: ___________ Lot # ____________
Date Received: ________________
Characteristic: Method Specification Actual Accepted
Company Visual Label “ABC Oil Company” ________________
Y or N
Product Name Visual Label “ Premium R&O 32” ________________
Y or N
Packaging Visual 5gal Drum ________________ Y or N
Quantity Ordered Count 1 Each ________________ Y or N
Appearance Visual No Visible Debris ________________ Y or N
Color Visual Light Yellow ________________ Y or N
Clarity Visual Clear and Bright ________________ Y or N
Viscosity @ 40C cSt D-445 28.8 -35.2 ________________ Y or N
Zn, P, Ca, Ba, Mg D-4951 <1 PPM Each ________________ Y or N
Particle Count In-house ISO 16/13 ________________ Y or N
Important: Attach laboratory data/report sheets to back of this form.
Approved by:______________________ Date: ________
Not Approved by: __________________ Date: ________
Explanation if Not Approved:
Unsatisfactory Chemical / Physical Properties
There are many chemical and/or physical characteristics of a lubricant
that can affect lubricants. Often problems in physical or chemical
properties may not be seen using methods designed to measure contamination.
In these cases and when warranted, performance testing should used.
If the specific performance criteria are not met there, further investigation
may be carried out to determine the reason. Performance testing might
include Rust Preventative Characteristics, ASTM D-665, Water Separability
Characteristics, ASTM D-1401 or antioxidant performance as measured
by ASTM D-2272, Rotating Bomb Oxidation Test (RBOT). If these characteristics
are important to the success of your operation, they should be evaluated.
The forms previously used can be modified to include these analyses.
Conclusion
In today’s environment of quality management, some level of
lubricant evaluation and acceptance is mandatory in all modern plant
operations. The levels of evaluation and the acceptance criteria should
be tailored to your plants needs. Once accepted, lubricants should
be maintained and distributed in such a manner that their integrity
is not compromised. In the short term, the evaluation of new lubricants
will ensure you have the correct lubricant for each machine this minimizes
mechanical, safety and legal problems that would otherwise affect
your operations. In the long, term this process will streamline the
entire lubrication process and increase productivity if it is further
refined to include used-oil analysis. The use of used-oil analysis,
controlled receipt inspections and a lubricant management program
will optimize your predictive maintenance efforts and pay big dividends
to your companies bottom line.
For more information call 1-888-HERGUTH (437-4884)
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