Oil Analysis Blog-

Results for tag "acid-number"

Are Your Engines NESHAP Compliant?

KarrieWilliams

 

Click on the image to read the article

Click on the image to read the article

 

As part of an effort to reduce engine emissions, the U.S. Environmental Protection Agency (EPA) adopted new national emission standards for hazardous air pollutants (NESHAP) in 2010.  The new regulations apply to existing stationary compression ignition (CI) and spark ignition (SI) reciprocating internal combustion engines at area and major sources of hazardous air pollutants (HAPs).

This regulation, known as RICE NESHAP, NESHAP Subpart ZZZZ, Quad-Z, or RICE MACT, will require sources to achieve emission limits reflecting the application of the maximum achievable control technology (MACT), consistent with sections 112(d) of the Clean Air Act.

Under RICE NESHAP, facilities with stationary engines are required to meet stringent emissions standards, verify compliance, perform maintenance activities, and report their continued compliance to the EPA.  The process to achieving compliance will require the implementation of new processes, methods, and systems, each unique to the respective operator and unique operating conditions and locations.

With nearly 1.5 million stationary engines in the U.S. to be affected, there are lots of people searching for knowledge on the requirements of this new ruling.  However, as with any Federal regulations, the reading can be extensive, confusing and the process to achieving compliance quite intimidating.

To learn more about RICE NESHAP click on the magazine cover.

Understanding Oil Analysis: How It Can Improve Reliability of Wind Turbine Gearboxes

KarrieWilliams
Click on the image to read the article

Click on the image to read the article

 

Reliability has been defined as the ability to rely on equipment to produce what it is scheduled to produce, when it is scheduled to produce it, for as long as it is scheduled to produce it with no interruptions. In the wind power industry, achieving reliability is simple in theory yet difficult to achieve.

Historically, wind turbine gearbox failures have plagued the industry. In order to improve reliability three major challenges must be met. First, a thorough understanding of gearbox loads is needed. Second, gearbox components must be properly designed and specified. Finally, lubricating oil in the gearbox must be kept cool, clean and dry and routinely analyzed to provide valuable information on the condition of the oil and gearbox.

This article published by Gear Technology and co-authored by Michael Barrett, TestOil and Justin Stover, C.C. Jensen, focuses on this third aspect of reliability; understanding lubrication, oil analysis and the vital role it plays in the life of the wind turbine gearbox.

Click on the magazine cover to read more.

How To Monitor Your Turbine Oil’s Health

KarrieWilliams

Turbine oils, particularly those used in steam turbines, are expected to last 10 to 20 years. During this lifespan careful monitoring of both lube oil physical and chemical properties, together with common contaminants such as water and solid particles, is required and should be performed annually. This is true not just of in-service oils, but also for new oils, which must meet rigorous performance specifications prior to selection and use in a new application.

TestOil’s Annual Turbine Analysis Report is a comprehensive turbine test package that provides a detailed analysis of the health of your turbine oil and contains the following tests:

View a sample turbine report

View a sample turbine report

Understanding Your Test Results

Our Annual Turbine Analysis Report is a 9-page analysis summarizing each of the tests we perform and containing a detailed explanation of each test result. The report also contains a summary of finding, as well as recommended actions as identified by our analysts. Click on the report cover above to view a sample report.

To learn more about our Annual Turbine Oil Analysis Report, please contact:

Angela Ritchie
arivera-ritchie@testoil.com
Phone: 216.251.2510

Measuring Varnish Potential in Lube Oil

KarrieWilliams

Lubricating oil in gas turbines and hydraulic systems is unfortunately subject to the ravages of varnish. It is well-documented that varnish is an insoluble contaminant comprised of oil degradation by-products and sometimes depleted additive molecules. It is generally caused by some type of thermal (heat-related) stress placed on the oil. The debilitating effects of varnish include the loss of operating clearances within machinery and a loss of heat transfer due to thermal insulating. As more operators face the prospect of varnish in their lube oil systems, they are turning to oil analysis labs for answers.

Varnish: The Elusive Enigma

Whether tending to a gas turbine or a large hydraulic system, the mere mention of varnish can cause alarm and an immediate call to action.

“It’s very important that a gas turbine and the hydraulic system work every time you start up or make changes. The cost of not starting up when required, or causing shutdowns, can cost in the thousands,” says Raymond R. (Bob) Nichol, Predictive Specialist for a major US power company. “We check for varnish potential every six months and act on it if we start to see the varnish potential increase. The bottom line is by keeping the varnish potential under control, the equipment works when needed and keeps the lube oil from losing the additives, amine and phenolic antioxidants.”

A number of explanations for the increasing occurrence of lube oil varnish have been postulated. Tighter filtration requirements, higher lube oil flow rates, higher operating temperatures and the switch to Group II base stocks in oil formulations have been offered as potential culprits in the decimation of lube oil systems. Varnish can often lead to unplanned outages and costly downtime, therefore, understanding and responding to varnish with remedial filtration is critical. Unfortunately, the ability to accurately measure varnish potential has remained elusive in routine testing.

“We work with power plants all over the country and their number one concern is varnish, specifically, making sure we are performing the necessary tests to alert them of a potential varnish problem,” notes Michael Barrett, Vice President, Sales & Marketing, TestOil. “We are continually looking for ways to improve the methodologies and technologies used in our laboratory to help customers solve problems.”

Measuring Varnish Potential

A varnish potential analysis (VPA) is used to signal the development of lube oil varnish potential. This analysis combines multiple testing technologies to measure a lubricating oil’s propensity to create varnish deposits.

This analysis combines the results of the following individual tests to provide a complete picture of a lube oil’s varnishing potential.

  1. Membrane Patch Colorimetry (MPC): This is an excellent tool in determining the varnish potential of an oil. This is a laboratory method of extracting insoluble contaminants from a used oil sample, followed by spectral analysis of the separated material. The process of making a patch isolates and agglomerates insoluble by-products associated with varnish. The color of the membrane patch provides a guideline as to the extent of varnish potential. With MPC, a direct correlation is made between the color and intensity of the insoluble contaminants and oil degradation. The test is designed to identify soft contaminants directly associated with oil degradation. This test is considered to be highly sensitive and reliable for detecting subtle changes in insoluble levels. As part of the MPC the L, a, b color values are also documented. The L, a, b values provide additional information on the particular varnish degradation mode and offer clues about the effectiveness of filtration targeting specific varnish modes. The L value is a black to white scale. The higher the L value, the higher the concentration of black particles in the oil. Black color can be due to soot particles, which can point to micro-dieseling, spark discharge, or hot spots. The a value is a red to green scale. The higher the a value, the greater the danger of sludge-building corrosive particles or diminished extreme pressure (EP) additives. Lastly, the b value is a yellow to blue scale. The higher the b value, the more susceptible the oil is to sticky deposits.
  1. Particle Count: Particulate contamination is tested using two methods, optical and pore blockage. Optical particle count passes the oil through a beam of light. Anything in the oil that interrupts the beam is counted as a particle. This method will count soft (varnish) particles. Pore blockage particle count passes the oil through a calibrated mesh screen that captures only hard particulates. A significant difference in the two results may be due to the presence of water, soft contaminants, or insoluble contaminants.
  2. Ultra Centrifuge Test: A small amount of oil in a test tube is run for 30 minutes at 18,000 RPM in an ultra centrifuge. By subjecting the sample to significant G-forces, we are able to extract oil-degraded insoluble contaminants that are associated with varnish potential. Insoluble contaminants tend to have a higher density and will drop out during testing. The amount of the agglomerated material is compared to a rating scale to derive the UC value (1-8). This test is considered an excellent indicator of varnish potential.
  3. Remaining Useful Life Evaluation Routine (RULER®): The RULER test uses linear sweep voltammetry to measure hindered phenolic and aromatic amine antioxidant content. The RULER quantitatively analyzes the relative concentrations of antioxidants in new and used oils in order to monitor the depletion rates of the antioxidant protection package in the oil. Hindered phenols and aromatic amines are primary antioxidants used in many industrial oils and turbine oil applications. By measuring the depletion and available reactivity of these antioxidant compounds while conducting other routine performance tests, the service life of used lubricants can be effectively monitored.
  4. Acid Number: A significant increase in the acid number could be indicative of rising carboxylic acids associated with an oxidation condition. Monitoring the acid number alerts us to an increasing risk of oxidation. A rapidly rising acid number indicates antioxidant depletion.
  5. Karl Fischer Method: This water determination test quantifies the amount of water in the lubricant. A reagent is titrated into a measured amount of sample and reacts with the OH molecules present in the sample. Results are reported as either a water or ppm percentage (1% =10,000ppm). Increased water concentrations indicate possible condensation, coolant leaks, or process leaks around the seals.
  6. IR Spectroscopy: The FTIR turbine method (only in use for turbine oils for which we have a reference) covers the monitoring of base stock degradation, oxidation and additive depletion in machine lubricants, hydraulic fluids and other fluid types. This test is based on trending of different parameters in various oils and fluids. For the turbine oil method, thermal event acid and acid oxidation are indicators of lubricant degradation. Ester, aromatic additive and base oil aromatic provide formulation information and should correlate with new oil data. Amine antioxidants and phenolic antioxidants are oxidation inhibitors with data expressed in indexing numbers.

Fighting Back Against Varnish

Varnish potential analysis should be considered a mandatory tool for any lube system that is prone to varnish. By controlling factors that influence or promote lubricant degradation, machine reliability and availability increases. By monitoring the contaminants responsible for varnish, reliability managers and maintenance planners can implement appropriate corrective actions before costly damage occurs and unnecessary downtime is experienced.