• COVER STORY: VELAN •
Redefining Thermal Protection
How advanced materials and technology in additive manufacturing, maintenance strategies, and engineering design can solve long-standing challenges in extreme conditions.
• By Fadila Khelfaoui, Corporate Engineer – Velan; Luc Vernhes, Mechanical Engineer – Velan
In the world of severe service valves, reliability under extreme conditions is non-negotiable. For applications such as ebullated bed hydrocracking, where oil exits the reactor at temperatures approaching 850 ° F and pressures above 3,000 psi, the sudden thermal shocks imposed on valves can lead to cracking, leakage, and costly downtime.
Velan recently introduced a solution to this challenge: an additive manufactured( AM) thermal sleeve, branded Hexa-Shield™, designed to protect valves from the most punishing thermal cycling conditions. By harnessing advanced lattice geometries inside a double-walled Inconel sleeve, this technology has redefined how valves can be protected from rapid temperature fluctuations, improving durability while simplifying manufacturing compared to traditional thermal barrier coatings( TBCs).
Hexa-Shield™ AM sleeves prepared for commercial supply, showcasing scalable production.
It clearly exemplifies how advances in materials engineering, maintenance strategies, and manufacturing technologies are converging to solve long-standing challenges in the oil and gas sector.
Severe Service Valve Challenges and Advanced Thermal Protection
Ebullated bed hydrocracking is a refining process used to upgrade heavy oils into lighter, more valuable products. In this process, reactors operate at elevated temperatures up to 850 ° F and pressures as high as 3,500 psi with bubbling providing continuous mixing of reactants and catalysts.
Fresh catalyst is injected through designated valves( refer to location # 5 in Figure 1), while spent catalyst is withdrawn through others( location # 6 in Figure 1). These valves cycle daily to sustain uninterrupted operation.
This routine exposes valves to extreme thermal cycling, which is one of the most severe environments for valve operation. Differential temperatures within the catalyst flow can induce thermal stress, deformation, and premature fatigue cracking in the valve body.
End users have reported instances of thermal fatigue cracking, as confirmed through cross-sectional inspections, highlighting the challenges of maintaining reliable valves in this service.
6 Valve World Americas | October 2025 | www. valve-world-americas. com