Grease Analysis

MRG concentrates on delivering high-value grease analysis.MRG concentrates on delivering high-value grease analysis. By incorporating the Grease Thief© and the Grease Thief Analyzer into the testing procedure, we are able to deliver highly accurate and meaningful analysis with less than two grams of in-service grease.  Grease analysis is valuable not only for determining the condition of the lubricant, but also for discovering abnormal conditions in equipment that may otherwise lead to unexpected failures. Our advanced test slate includes tests that are designed to identify the specific modes that may be damaging the component. Each of our analysis reports comes with recommendations unique to the component to improve reliability.

Our analysis evaluates grease condition based on four categories:

We offer 3 tests for grease analysis:

Screening Test

FdM+ Ferrous Debris Analysis

Analex

Purpose

Ferrous Debris Monitoring (FdM+) is used to quantify the ferrous content of used grease samples. It is a primary indicator of wear levels.

 

Method

The FdM+ uses an electro-magnetic coil to measure iron content. The sensor detects the ferrous debris distributed throughout the entire sample as the Grease Thief is dropped into the instrument. This helps avoid inaccurate results due to aliquoting the sample or instrumental particle size limitations, which are the two major issues that can arise when using other methods to track wear levels. Results are reported in parts per million (ppm).

FT-IR Spectroscopy

FT-IR Spectroscopy

Purpose

Fourier Transform-Infrared Spectroscopy (FT-IR) is used to determine the chemical properties of a compound in a qualitative manner. Oxidation products can be detected using this spectroscopic technique. Contamination, including mixing with incompatible greases is easily detected using this method.

 

Method

A small quantity of grease is subjected to a spectrum of infrared radiation. Specific wavelengths of infrared radiation excite the chemical bonds that make up the grease and generate a unique spectral fingerprint. This fingerprint can be compared to baseline data to determine chemical changes in grease composition.

Colorimetry

Colorimetry

Purpose

Grease colorimetry testing is used to validate observed appearance changes in greases, trend darkening due to aging or overheating, characterize dye formulations of new greases, and may even approximate the concentration of certain particulate contaminants, such as coal dust or other solids accumulating in the grease.

 

Method

A thin film of the grease sample is loaded into a dark chamber and exposed to the spectrum of visible light (400-700 nm). The relative intensity of the light that is aborbed at each wavelength is measured and an absorption spectrum graph is generated. This visible spectrum is characteristic of grease color and can be used to indicate grease color changes that are not quantifiable by the human eye.

Basic Grease Analysis Slate

RDE Spectroscopy

RDE Spectroscopy

Purpose

Rotating Disc Electrode (RDE) Spectroscopy is an atomic emission spectroscopy method that quantifies the elements that are present in the lubricant. These elements include wear metals such as iron, copper and zinc, additive elements such as magnesium and phosphorus, and grease thickeners such as calcium and sodium. RDE spectroscopy therefore can be used to evaluate wear and contamination properties of a sample.

Method

In this atomic emission spectroscopic method, a small portion of the dissolved sample is ignited between two carbon electrodes. The various wavelength of light that are emitted by the sample as it burns are measured. The various wavelengths that are present and their relative intensity are used to quantify the individual elements that are present in the sample.

FdM+ Ferrous Debris Analysis

Analex

Purpose

Ferrous Debris Monitoring (FdM+) is used to quantify the ferrous content of used grease samples. It is a primary indicator of wear levels.

 

Method

The FdM+ uses an electro-magnetic coil to measure iron content. The sensor detects the ferrous debris distributed throughout the entire sample as the Grease Thief is dropped into the instrument. This helps avoid inaccurate results due to aliquoting the sample or instrumental particle size limitations, which are the two major issues that can arise when using other methods to track wear levels. Results are reported in parts per million (ppm).

FT-IR Spectroscopy

FT-IR Spectroscopy

Purpose

Fourier Transform-Infrared Spectroscopy (FT-IR) is used to determine the chemical properties of a compound in a qualitative manner. Oxidation products can be detected using this spectroscopic technique. Contamination, including mixing with incompatible greases is easily detected using this method.

 

Method

A small quantity of grease is subjected to a spectrum of infrared radiation. Specific wavelengths of infrared radiation excite the chemical bonds that make up the grease and generate a unique spectral fingerprint. This fingerprint can be compared to baseline data to determine chemical changes in grease composition.

Colorimetry

Colorimetry

Purpose

Grease colorimetry testing is used to validate observed appearance changes in greases, trend darkening due to aging or overheating, characterize dye formulations of new greases, and may even approximate the concentration of certain particulate contaminants, such as coal dust or other solids accumulating in the grease.

 

Method

A thin film of the grease sample is loaded into a dark chamber and exposed to the spectrum of visible light (400-700 nm). The relative intensity of the light that is aborbed at each wavelength is measured and an absorption spectrum graph is generated. This visible spectrum is characteristic of grease color and can be used to indicate grease color changes that are not quantifiable by the human eye.

Die Extrusion Testing

Die Extrusion

Purpose

Die Extrusion testing uses the innovative design of the Grease Thief© and the Grease Thief Analyzer to measure the consistency of a grease sample. The consistency of a used sample is compared to the consistency of the baseline to generate the dimensionless Grease Thief Index, describing how the consistency of the grease has changed.

Method

Grease is extruded from the full Grease Thief through a small die using the Grease Thief Analyzer. As the grease is extruded, a force probe measures the force required to extrude the grease through the small die channel. Extrusion occurs at three speeds in order to create a consistency profile. This method allows grease consistency to be measured with only a gram of grease, significantly reducing necessary sample volume for useful consistency testing.

Advanced Grease Analysis Slate

Analytical Ferrography

Analytical Ferrography

Purpose

Analytical ferrography involves the examination of ferrous debris from a lubricant sample by a qualified laboratory analyst. The analyst may determine wear modes that generated wear specific particles and diagnose abnormal component conditions based on this analysis.

Method

The lubricant is dissolved in organic solvent. It then slowly flows over a microscope slide that is subjected to magnetic field. Ferrous particles are trapped on the slide while non-ferrous particles wash away. These ferrous particles are then examined under high magnification by a laboratory analyst in order to assess generative wear modes.

Grease Rheometry

Rheometry

Purpose

Grease Rheometry is an advanced analysis technique that measures various physical properties of grease related to consistency. Oscillation stress, recoverable compliance and G1 values of the grease sample are measured to assess lubrication ability of grease.

Method

A small sample of grease is introduced to the rheometer and heated to operating temperature. Various forces are applied to the grease to simulate working conditions and response is quantified in order to measure grease consistency.

RULER Testing

RULER Testing

Purpose

Remaining Useful Life (RULER) testing measures the percent of anti-oxidant additive package that remains in the lubricant compared to the baseline. This test shows show if the lubricant is at elevated risk for oxidation.

Method

A portion of the lubricant is exposed to a solvent that extracts anti-oxidants from the lubricant. This extract is subjected to linear sweep voltammetry which measures the change in current as a conducting compound, such as an anti-oxidant, is subjected to linearly increasing potential. The current response of the sample is compared to a baseline to determine the percent of anti-oxidant protection that remains.

Grease Particle Counting