Pressure Pulsation Tests
The purpose this post to highlight some of the insights into the selection and capabilities of Bubble-Point Test Systems and is not intended to go into the testing physics, analysis of the test data, or the correlation / determination of element pore sizes behind the testing itself. An in-depth discussion for this expanded data can be found in standards such as the ARP901-B Aerospace Recommended Practice / Bubble-Point Test Method available from SAE International publications.
It is important when working with hydraulic equipment that you understand what fluid you are dealing with and what its characteristics are. Most fluids are incompatible with other fluids and would often require changes to seals or other system components to be able to switch between fluids. Also, each has its own health and safety considerations.
When beginning a project to create a data acquisition, control, or test system, the main two concerns are often “How can we keep costs low?” and “How quickly will it be up and running?” Unfortunately, that can lead to rushing through the most important first step: the creation of a detailed project requirements document.
The proper testing of each component during development is especially crucial for in-flight critical applications because a failure of even the smallest component can have catastrophic results. Additionally, applications in these types of industries often have complex hydraulic components, use exotic fluids, or need to have fail-safe functionality in high-pressure environments, which creates even more complicated test scenarios.
One of the greatest growth areas for Wineman Technology are our lines of pressure impulse and pressure pulsation test systems. During the quoting process, our customers usually ask several questions to see how our engineered system’s capacities compare with several of our competitors “off the shelf” product lines. The main and perhaps the most important question that they ask is “Why are you asking me all of these questions about what we are testing and how we are testing it?” This blog post will hopefully highlight some of the differences in the WTI engineered system’s approach, why we ask so many questions, and if what you are buying really measures up.
Each month we receive multiple requests for “pressure cycling test stands”. The first question we ask of our customers is: “Are you looking for an impulse test stand or a pressure pulsation test stand”? This question is generally followed by a long pause and their response: “What’s the difference”? This then leads us to the next question: “Is the test closed-ended or open-ended?” Here comes the second long pause. While not intended to be a white paper or in-depth discussion, the goal of this article is to simply outline our definitions and how we internally separate and market the two systems within the Wineman Technology line of servo hydraulics products. Future articles will go into greater depths of the test parameters and specifications of each these two product lines.
If you’re designing hydraulic systems, especially in the commercial and military aircraft industries, you’re under a lot of pressure to keep pace with innovation and new technology, get to market faster, and optimize both cost and man-hour resources.
There’s little room for error, and components need to work both individually as well as seamlessly with a complex system that includes numerous variables and external influences.
In our new white paper, called “Validating Aircraft Hydraulics with a Full-Scale Test Cell,” we discuss the challenges faced by hydraulic system designers and walk through an example of how we helped a customer use off-the-shelf, modular hardware, a flexible software interface, and actual system components to create a highly efficient test stand for testing aerospace hydraulic components under a variety of possible real-world scenarios.