Staff Mechanical Engineer, Sealing Systems
Confirmed on the employer's own hiring board on Sep 23, 2026. First seen by Alion on Sep 18, 2026. Mainspring Energy scores A on the Alion truth index.
Job Overview
The Rings team owns one of the hardest technical problems in the Linear Generator: a piston and ring system that seals without liquid lubricant. Getting this right is foundational to the product’s low emissions and maintenance business model. The design space is demanding, with complex sealing geometry, demanding thermal and pressure conditions, and material performance and system behavior that all need to be considered simultaneously. Progressing the ring service interval is one of the most important development programs at Mainspring. As a Staff Mechanical Engineer on this team, you will take ownership of a significant piece of that challenge.
What You’ll Do
Lead ring and piston development projects, including setting requirements and scope, developing novel designs, reviewing colleagues' designs and analyses in detail, and building production introduction plans
Design complex moving parts in the piston and ring system, from originating ideas through detailed design, build, test, and evaluation of performance
Assess and root cause failures that involve coupled thermal, structural, materials, and fluid interactions, balancing analysis with hands-on physical intuition
Design and run effective test campaigns, using both benchtop rigs and in-generator experiments, to validate designs and accelerate learning
Discover and define requirements on surrounding subsystems to improve ring and piston performance
Collaborate closely with a talented engineering team in a fast-paced, iterative environment to find the best solutions
What We’re Looking For
Master's degree in Mechanical Engineering or equivalent with at least eight years of experience, or a Ph.D. with at least five years of experience
A proactive and collaborative work style suited for a dynamic R&D environment where priorities can evolve as you learn, including comfort with problems that cross team boundaries and engineering disciplines
Experience designing high-performance, precision parts from R&D through to production release
Fluency in SolidWorks or a comparable CAD package. Comfortable using structural and thermal FEA as a design tool (Ansys is a plus)
Ability to generate 2D drawings for manufacturing, including comfort with GD&T
Excellent physical understanding and intuition in structural mechanics and heat transfer; strength in tribology, fluid mechanics, or thermodynamics is a plus
A systems approach to problem solving: Prefers to look at the whole system to identify negative interactions and opportunities for improvement
Nice to Have
Excellent understanding of thermodynamics, experience interacting with a complex thermodynamic system. Power generation, energy storage, and aerospace (especially turbomachinery or propulsion) are all extremely relevant
Experience designing for high-cycle fatigue and high-pressure, high-temperature environments. Experience with super alloys is a plus
Fluency in Python programming for data analysis, and experience developing and validating simplified models of systems and subsystems to inform failure analysis and design