What is ISO 21018-4 - Hydraulic fluid power about?
ISO 21018 is a series on hydraulic fluid power. Hydraulic fluid power is the power derived from the energy of falling or fast running water. ISO 21018-4 specifies a method for the determination of the particulate contamination level using the light extinction technique (also known as light blockage or light obscuration) either online or offline in containers. ISO 21018-4 also defines procedures for calibrating the instruments and verifying their correct operation both in the laboratory and in service.
In general, the techniques described in ISO 21018-4 are suitable for monitoring:
- The general cleanliness level in hydraulic systems
- The progress in flushing operations
- Support equipment and test rigs
The use of this method is applicable to single-phase liquid systems only.
Who is ISO 21018-4 - Hydraulic fluid power for?
ISO 21018-4 on hydraulic fluid power is useful for:
- Hydraulic fluid power container manufacturers
- Hydraulic system component and equipment manufacturers
- Hydraulic fluid power plant
- Design engineers
- Quality control personnel
Why should you use ISO 21018-4 - Hydraulic fluid power?
Hydraulic fluid power is generally used for low-pressure, high volume flow applications. In hydraulic fluid power systems, power is transmitted through a liquid under pressure within a closed circuit. The liquid is both a lubricant and a power-transmitting medium. The presence of solid contaminant particles in the liquid interferes with the ability of the hydraulic liquid to lubricate and causes wear. The extent of contamination in the liquid has a direct bearing on the performance and reliability of the system and should be controlled to an appropriate level.
Quantitative determination of particulate contamination requires precision both in obtaining a representative sample of the liquid and the measurement of the contamination. The awareness of the benefits of cleanliness monitoring have led to the development of instruments that operate online (i.e., directly connected to a system) in an attempt to reduce measurement errors that are inherent with bottle samples. ISO 21018-4 introduces Particle contamination monitors (PCM) that have been developed for this purpose and are extensively used. Instruments using this technique have become widely used in the industry and an international standard is required in order to standardize operating procedures. ISO 21018-4 defines procedures for the use of light extinction instruments in evaluating the cleanliness level of a hydraulic liquid. ISO 21018-4 also includes procedures for calibrating and verifying that the instruments are operating correctly to ensure consistent results. Using ISO 21018-4 you can specify a method for the determination of the particulate contamination level using the light extinction technique.
What’s changed since the last update?
BS ISO 21018-4:2019 supersedes BS ISO 21018-4:2016. BS ISO 21018-4:2019 includes some technical changes with respect to BS ISO 21018-4:2016. These include:
- Simplification of calibration procedure in Clause 7
- Moving the equipment for the calibration and validation procedure from Clause 5 to Clause 7 after the Operating Procedures