Hydrogen, with its unique chemical and physical properties, presents significant challenges in industrial applications, particularly sealing and containment. Choosing the right gasket for hydrogen service is crucial to ensuring safety, preventing leaks, and maintaining system integrity. Below, we’ll explore key considerations when selecting a gasket for hydrogen applications and highlight some effective solutions from KLINGER.
1. Understanding Hydrogen’s Properties
Hydrogen is the smallest and lightest element, which makes it particularly challenging to seal. Due to its small molecular size, hydrogen can permeate through many materials that are typically suitable for other gases. Additionally, hydrogen embrittlement – the degradation of materials upon exposure to hydrogen – can severely impact metals, making material selection a critical step.
2. Material Compatibility
The gasket material must be compatible with hydrogen to avoid degradation and leakage over time. When choosing the right gasket, consider:
Metal Gaskets
These are often preferred for high-pressure hydrogen applications due to their durability and resistance to permeation. Common materials include stainless steel or nickel alloys that resist hydrogen embrittlement.
Non-metallic Gaskets:
PSM Graphite-based gaskets or KLINGER TopChem PTFE are often chosen for lower-pressure applications due to their flexibility and chemical resistance. These materials effectively handle the cold temperatures that can occur with hydrogen systems. The KLINGERSil range of materials have been used for many years in Hydrogen applications.
3. Pressure and Temperature Requirements
Hydrogen systems can operate under extreme conditions, including high pressures and a wide range of temperatures. Gaskets must be selected based on their ability to maintain their sealing properties under these conditions. For example, metal gaskets like spiral wound or ring joint gaskets are commonly used in high-pressure environments, as they can handle both mechanical stress and temperature fluctuations.
Materials with good low-temperature flexibility, such as PTFE or specialized graphite, should be considered for cryogenic applications. PTFE, in particular, maintains performance at low temperatures and offers excellent sealability. KLINGER has a long history of using gaskets in hydrogen applications and in many cases KLINGERSil materials offer good sealing performance and reliability.
4. Gasket Design and Structure
The structure of the gasket is just as important as its material. For hydrogen applications, spiral wound gaskets with flexible graphite filler or metal-core gaskets offer both strength and a reliable seal, especially in high-pressure systems. The resilience of these gaskets allows them to maintain an effective seal even under fluctuating conditions.
5. Gaskets for Hydrogen Service designed by KLINGER
The subsidiaries of KLINGER Group offer a range of gaskets designed for demanding applications, including those involving hydrogen. Their metal gaskets, such as the KLINGER Spiral Wound Gaskets and KLINGER PSM Graphite Laminate Gaskets, are engineered to withstand high pressure and aggressive media like hydrogen. For cryogenic services, KLINGER’s TopChem PTFE-based products offer the flexibility and gas tightness needed for effective sealing in hydrogen applications.
