What is ISO 2942 - Hydraulic fluid power about?

ISO 2942 discusses hydraulic fluid power. In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure within an enclosed circuit. ISO 2942 specifies a bubble-point test method applicable to filter elements used in hydraulic fluid power systems. ISO 2942 can be used both to verify the fabrication integrity of a filter element (by checking the absence of bubbles) and to permit the localization of the largest pore of the filter element by determining the first bubble point.

The first bubble point is established through the continuation of the fabrication integrity test. It is under no circumstances a functional characteristic of a filter element; in particular, it cannot be used to estimate filtration rating, efficiency or retention capacity and is intended to be used for information only. ISO 2942 specifies a method to normalise fabrication integrity and bubble point data to a standard value of surface tension when test fluids other than 2-propanol are used.

Who is ISO 2942 - Hydraulic fluid power for?

ISO 2942 on hydraulic fluid power is useful for:

Hydraulic fluid power machinery manufacturers
Cylinders manufacturers
Design engineers
Quality control personnel
Research and development facilities
Fabrication sector

Why should you use ISO 2942 - Hydraulic fluid power?

In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure within an enclosed circuit. Filters maintain fluid cleanliness by removing insoluble contaminants. The ability of a filter to achieve and maintain the required level of performance depends, among other parameters, upon its filtration rating and structural integrity. Any imperfections in the structure, either through poor manufacturing techniques or lack of strength, allow by-passing of unfiltered fluid.

The integrity of the element after manufacture can be evaluated using a non-destructive filter integrity test which is discussed in ISO 2942. This test determines whether flaws are present which would allow the fluid to bypass the filtering process and provide for quality control. The test is also used to evaluate whether damage has been sustained by the element during both service and laboratory tests.

ISO 2942 discusses the first bubble point test which is used for investigative product development or production process evaluation. The acceptability of filtration performance cannot be determined by the first bubble point test. Using ISO 2942 you can specify a bubble-point test method applicable to filter elements used in hydraulic fluid power systems.

What’s changed since the last update?

BS ISO 2942:2018 supersedes BS ISO 2942:2004. BS ISO 2942:2018 includes some technical changes with respect to BS ISO 2942:2004. These include:

In 4.2, acceptable test fluids for the determination of fabrication integrity are defined
In 5.2.1, a formula to calculate the minimum allowed fabrication integrity pressure for an element in the test liquid is provided
In 5.3.1, a formula is provided to calculate the pressure normalized to the surface tension of 2-propanol
In annexe a, the manufacturer’s minimum specified fabrication integrity is now listed, as well as the first bubble point in the test liquid and the normalized first bubble point
In annexe b, the theoretical underpinning for relating bubble point data obtained in one fluid to the bubble point that would be obtained using a different fluid is presented

BS ISO 2942:2018

Hydraulic fluid power. Filter elements. Verification of fabrication integrity and determination of the first bubble point

Current

Published:

31 Oct 2018