Formation of bubbles, embrittlement and, in extreme cases, ruptures in the pipework: When working with hydrogen (H2), you need a few technological tricks up your sleeve. “Its chemical properties make hydrogen difficult to handle. For example, it can diffuse into metals that it comes in contact with,” says Gerhard Gruber, Application Engineer at KLINGER Fluid Control. Based in the Austrian Gumpoldskirchen, the company has already gained plenty of experience in handling the tricky medium and, as a result, made significant advances regarding its products’ leakage rate and service life.
Contacts mentioned in the article:
Gerhard Gruber, Application Engineer at KLINGER Fluid Control
Durable design for hydrogen
The current state of the art is embodied in the Ballostar KHSVI, which has a number of key benefits that make this ball valve the obvious choice for hydrogen applications.
“The valve body is made of two parts. These are joined together with a single weld seam that runs parallel to the direction of flow. Both parts are castings, which allows a very robust design,”
Gerhard Gruber is Application Engineer at KLINGER Fluid Control.
Just how robust can be seen in computer simulations: Only low forces act on the valve’s components inside its stress-optimized body, which extends its service life.
PTFE sealing material proven for use with hydrogen
The sealing system, too, is designed for resistance and durability. It is elastically rather than spring mounted, making it insensitive to fluctuations in temperature and pipe pressure. “What’s also important is that the sealing ring is fixed from three sides to prevent the sealing material from breaking away,” says Gruber. The go-to sealing material at KLINGER Fluid Control is PTFE, which is tried and tested in hydrogen applications.
Austenitic steels
The same applies to the valve material: Austenitic steel is the material of choice here, as hydrogen cannot diffuse into it and cause embrittlement. The valve’s internal geometry has been carefully designed to avoid sharp edges or corners where the hydrogen atoms would be able to penetrate the metal. In designing the chrome-plated ball, impediments to the flow of the medium were avoided wherever possible: A full, linear media flow was the top design priority.
Compliant with TA-Luft: ball valve for H2
With a volatile gas, such as hydrogen, the tightness of valves is also of prime importance. To this end, the Ballostar KHSVI features a quadruple stem seal with O-rings, which also means that it meets the emission requirements for hydrogen use, such as those specified in the German TA Luft air pollution control regulation. For practical use in hydrogen applications, the ball valve is particularly suitable for hydrogen handling and production systems that work at low pressure of up to 40 bars.
Fact box
Did you know …
- … that the stem of the Ballostar KHSVI ball valve is made entirely of stainless steel? A quadruple stem seal with O-rings guarantees leakage rate A. The O-rings can be replaced and meet the requirements of TA Luft and the VDI 2440 standard.
- … that KLINGER Fluid Control can perform an additional dye penetration test on the weld seam in the body of the Ballostar KHSVI? This ensures that the seam allows as little hydrogen as possible to pass through.
- … that the KLINGER Fluid Control Ballostar KHA ball valves are also ideal for hydrogen electrolysis and hydrogen infrastructure? With sizes ranging from DN15 to DN125, they can be used in common hydrogen applications and allow a bidirectional flow.
