ASTM D7624-22
Standard Test Method for Condition Monitoring of Nitration in In-Service Petroleum and Hydrocarbon-Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectrometry

Standard No.

ASTM D7624-22

Release Date

2022

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM D7624-22

Scope

1.1 This test method covers monitoring nitration in gasoline and natural gas engine oils as well as in other types of lubricants where nitration by-products may form due to the combustion process or other routes of formation of nitration compounds. 1.2 This test method uses FT-IR spectroscopy for monitoring build-up of nitration by-products in in-service petroleum and hydrocarbon-based lubricants as a result of normal machinery operation. Nitration levels in gasoline and natural gas engine oils rise as combustion by-products react with the oil as a result of exhaust gas recirculation or a blow-by. This test method is designed as a fast, simple spectroscopic check for monitoring of nitration in in-service petroleum and hydrocarbon-based lubricants with the objective of helping diagnose the operational condition of the machine based on measuring the level of nitration in the oil. 1.3 Acquisition of FT-IR spectral data for measuring nitration in in-service oil and lubricant samples is described in Practice D7418. In this test method, measurement and data interpretation parameters for nitration using both direct trend analysis and differential (spectral subtraction) trend analysis are presented. 1.4 This test method is based on trending of spectral changes associated with nitration in in-service petroleum and hydrocarbon-based lubricants. For direct trend analysis, values are recorded directly from absorption spectra and reported in units of 100*absorbance per 0.1 mm pathlength (or equivalently absorbance units per centimetre). For differential trend analysis, values are recorded from the differential spectra (spectrum obtained by subtraction of the spectrum of the reference oil from that of the in-service oil) and reported in units of 100*absorbance per 0.1 mm pathlength (or equivalently absorbance units per centimetre). Warnings or alarm limits can be set on the basis of a fixed maximum value for a single measurement or, alternatively, can be based on a rate of change of the response measured (1).2 In either case, such maintenance action limits should be determined through statistical analysis, history of the same or similar equipment, round robin tests or other methods in conjunction with the correlation of nitration changes to equipment performance. NOTE 1—It is not the intent of this test method to establish or recommend normal, cautionary, warning or alert limits for any machinery. Such limits should be established in conjunction with advice and guidance from the machinery manufacturer and maintenance group. 1.5 This test method is for petroleum and hydrocarbonbased lubricants and is not applicable for ester-based oils, including polyol esters or phosphate esters. 1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6.1 Exception—The unit for wave numbers is cm-1 . 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM D7624-22 Referenced Document

• ASTM D2896 Standard Test Method for Base Number of Petroleum Products by Potentiometric Perchloric Acid Titration
• ASTM D4175 Standard Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants*， 2023-07-01 Update
• ASTM D445 Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (the Calculation of Dynamic Viscosity)
• ASTM D5185 Standard Test Method for Determination of Additive Elements, Wear Metals, and Contaminants in Used Lubricating Oils and Determination of Selected Elements in Base Oils by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)
• ASTM D7412 Standard Test Method for Condition Monitoring of Phosphate Antiwear Additives in In-Service Petroleum and Hydrocarbon Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectr
• ASTM D7414 Standard Test Method for Condition Monitoring of Oxidation in In-Service Petroleum and Hydrocarbon Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectrometry
• ASTM D7415 Standard Test Method for Condition Monitoring of Sulfate By-Products in In-Service Petroleum and Hydrocarbon Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectrometry
• ASTM D7418 Standard Practice for Set-Up and Operation of Fourier Transform Infrared (FT-IR) Spectrometers for In-Service Oil Condition Monitoring*， 2023-05-15 Update
• ASTM E131 Standard Definitions of Terms and Symbols Relating to Molecular Spectroscopy
• ASTM E177 Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• ASTM E691 Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

ASTM D7624-22 history

• 2022 ASTM D7624-22 Standard Test Method for Condition Monitoring of Nitration in In-Service Petroleum and Hydrocarbon-Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectrometry
• 2021 ASTM D7624-21 Standard Test Method for Condition Monitoring of Nitration in In-Service Petroleum and Hydrocarbon-Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectrometry
• 2018 ASTM D7624-18 Standard Test Method for Condition Monitoring of Nitration in In-Service Petroleum and Hydrocarbon-Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectrometry
• 2010 ASTM D7624-10 Standard Test Method for Condition Monitoring of Nitration in In-Service Petroleum and Hydrocarbon-Based Lubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) Spectrometry