Method of detecting the extent of oil degradation

Patent metadata

Field	Value
Publication number	US-9804142-B2
Application number	US-201414323592-A
Country	US
Kind code	B2
Filing date	Jul 3, 2014
Priority date	Jul 3, 2014
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

A method of detecting the extent of degradation of an oil is provided. The method may comprise the steps of analyzing samples of the oil when fresh and when used; calculating electrochemical property data of the fresh and used engine oil; determining whether the electrochemical property data correlates with the degradation marker data; and using the electrochemical property to detect the extent of degradation of the oil of a used sample of the oil. The method may be used for any suitable oil, including mineral oil, synthetic oil and blends (a.k.a. semi-synthetic). The method can be used to maximize oil usage by monitoring used oil quality over time so that the oil is replaced when necessary and not before. The method can also identify trends in oil degradation.

First claim

The invention claimed is:

1. A method of detecting the extent of degradation of oil, the method comprising the steps of:
analyzing samples of a machine's oil supply when fresh and when used wherein the compounds within the oil supply are identified using a chemical compound measurement machine where compound changes are recorded as a function of time;
identifying at least one compound selected from the group consisting of alcohols that decrease by at least 1 area percent per 100 hours of machine operation, ethers that increase by at least 0.2 area percent per 100 hours of operation, and disulfides that increase by at least 0.5 area percent per 100 hours of operation as a degradation marker;
measuring a dielectric constant using an electrochemical property measurement machine where dielectric constant changes are recorded as a function of time;
selecting the dielectric constant as an oil degradation indicator when the dielectric constant correlates to the at least one degradation marker given at least a 0.02 dielectric constant increase per 100 hours of machine operation; and
communicating the extent of oil degradation based on the dielectric constant if the degradation markers correlate with the dielectric constant as a function of time.

2. The method of claim 1 wherein using the electrochemical property data of a used sample of the oil to detect the extent of degradation of the oil comprises the steps of:
taking an oil sample from a machine in the field;
analyzing the oil sample for those properties needed to measure the electrochemical property data;
measuring the electrochemical property data; and

using the electrochemical property data to decide whether to change the oil in the machine.

3. A method of detecting the extent of degradation of oil, the method comprising the steps of:
analyzing samples of a machine's oil supply when fresh and when used wherein the compounds within the oil supply are identified using a chemical compound measurement machine where compound changes are recorded as a function of time;
identifying at least one compound of a group consisting of alcohols that decrease by at least 1 area percent per 100 hours of machine operation, ethers that increase by at least 0.2 area percent per 100 hours of operation, and disulfides that increase by at least 0.5 area percent per 100 hours of operation as a degradation marker;
measuring a molar polarization using an electrochemical property measurement machine where molar polarization changes are recorded as a function of time;
selecting the molar polarization as an oil degradation indicator when the molar polarization correlates to the at least one degradation marker given at least a 1 cc mole −1 molar polarization increase per 100 hours of machine operation; communicating the extent of oil degradation based on the dielectric constant if the degradation markers correlate with the dielectric constant as a function of time.

4. The method of claim 3 wherein using the electrochemical property data of a used sample of the oil to detect the extent of degradation of the oil comprises the steps of:
taking an oil sample from a machine in the field;
analyzing the oil sample for those properties needed to measure the electrochemical property data;
measuring the electrochemical property data; and
using the electrochemical property data to decide whether to change the oil in the machine.

Assignees

• Caterpillar Inc

Inventors

• Basu Amiyo K
• Vinu R
• Tripathi Anand Kumar

Classifications

• G01N33/2888 Primary

  Lubricating oil characteristics, e.g. deterioration (lubricating properties G01N33/30) · CPC title

• G01N27/221

  by investigating the dielectric properties (using microwaves G01N22/00; measuring loss factors or dielectric constants per se G01R27/26) · CPC title

• G01N27/26

  by investigating electrochemical variables; by using electrolysis or electrophoresis · CPC title