Senior Mechanical Design Engineer — ASME Section III

Aalo Atomics•Austin, TX

24d•Onsite

About The Position

Aalo Atomics is seeking a Senior Mechanical Design Engineer with expert knowledge of ASME BPVC Section III to lead design of reactor vessels and pressure-boundary systems for a sodium-cooled, graphite-moderated reactor. This hands-on role is for an independent engineer who can contribute immediately in a fast-paced startup environment. The engineer will develop code-compliant designs, supporting analyses, and technical documentation while partnering with manufacturing, materials, quality, and licensing teams. The engineer will also play a central role in Aalo’s ASME certification efforts, supporting demonstration projects for N, G, and GC stamps and establishing the Section III design and compliance framework required for fabrication. The role owns designs from concept through release, fabrication support, testing, and verification, and includes creating CAD models, drawings, specifications, and calculation packages. The position requires working on-site in Austin, Texas, or Idaho Falls, Idaho. Applicants must be U.S. Citizens or U.S. Persons in compliance with 10 CFR Part 810 and may not hold non-compliant foreign citizenships.

Requirements

Bachelor’s degree in Mechanical Engineering or a related discipline.
At least 7 years of relevant mechanical design experience with pressure vessels, pressure-retaining equipment, or nuclear mechanical systems.
Expert knowledge of ASME BPVC Section III and its application to pressure-boundary design, including familiarity with Subsections NCA, NB, NC, ND, and NF.
Demonstrated experience with Section III design classification, including safety class, seismic category, and quality group, and applying code rules to establish design requirements.
Experience performing or reviewing Section III code calculations, including stress analysis, fatigue evaluation, and load-combination assessments.
Experience designing vessels, shells, heads, nozzles, penetrations, flanges, or similar structures.
Strong understanding of pressure-vessel mechanics, fatigue, buckling, thermal stress, and load combinations.
Ability to independently drive ambiguous technical work to documented engineering decisions.
Proficiency with 3D CAD and FEA or structural-analysis tools.
Based in the United States and willing to work on-site in Austin, Texas, or Idaho Falls, Idaho.
Applicants must be U.S. Citizens or U.S. Persons in compliance with 10 CFR Part 810 and may not hold non-compliant foreign citizenships.

Nice To Haves

Experience supporting ASME stamp certification (N, G, GC, NPT, or NA), including demonstration project planning, ANI coordination, and Design Report preparation.
Experience designing nuclear components in accordance with ASME BPVC Section III.
Experience with sodium-cooled, liquid-metal, high-temperature, or other advanced reactor systems.
Familiarity with elevated-temperature design, creep-fatigue, thermal transients, and high-temperature alloys, including ASME Section III Division 5 or Code Case N-47/N-861.
Experience developing Design Specifications, Design Reports, and Overpressure Protection Reports per Section III.
Experience with stainless steels, nickel-based alloys, weldments, and high-temperature fabrication.
Familiarity with ASME BPVC Sections II, V, IX, and XI.
Experience supporting fabrication, welding, inspection, pressure testing, or nonconformance resolution.
PE license.

Responsibilities

Lead mechanical design and ASME BPVC Section III compliance for reactor vessels, pressure-boundary components, supports, and penetrations.
Perform and own Section III code calculations for pressure, thermal, fatigue, buckling, seismic, and other design-basis and service-level loads.
Classify components and systems under NCA/NB/NC/ND requirements and establish the design classification framework for reactor pressure-boundary and safety-related equipment.
Apply Section III rules, including Subsections NB, NC, ND, NF, and NE as applicable, to pressure vessels, piping, supports, and containment structures; ensure correct load combinations, stress limits, and service-level criteria.
Develop Design Specifications, Design Reports, and Overpressure Protection Reports in accordance with Section III requirements.
Evaluate elevated-temperature design considerations, including creep, creep-fatigue, and thermal ratcheting where applicable.
Support demonstration projects for ASME N-stamp, G-stamp, and GC-stamp certification.
Develop technical deliverables, procedures, and documentation required for stamp certification, including Quality Assurance program support and Design Reports, and coordinate with the Authorized Nuclear Inspector (ANI).
Work with quality and manufacturing teams to establish compliant fabrication, examination, and testing processes that satisfy stamp requirements.
Own designs from concept through release, fabrication support, testing, and verification.
Create CAD models, drawings, specifications, and calculation packages.
Partner with manufacturing, materials, quality, and licensing teams to resolve design, fabrication, and compliance challenges.
Lead design reviews and communicate technical assumptions, risks, and trade-offs.
Support prototype builds, supplier engagement, fabrication issues, and testing.