Senior Mechanical Engineer

Thanks for your interest in Oklo! We are searching for a Sr. Mechanical Engineer to join our fuel recycling engineering team within Oklo's Recycling Division. Position Description You will serve as Oklo's technical expert for high-temperature process piping, pressure vessels, and pressure-retaining components supporting the Oak Ridge Fuel Recycling Facility (OFRF). You will own the mechanical design basis, analysis, code compliance, and technical interfaces for these systems from early design through fabrication, testing, installation, commissioning, and operational support. The work includes demanding hot-cell, molten-salt, inert-atmosphere, vacuum, and thermal-cycling service conditions. This role is for a technically rigorous mechanical engineer who is comfortable working from first principles, developing and reviewing detailed analytical models, and owning mechanical equipment designs from early concepts through fabrication, testing, hot-cell installation, and operation. Success requires strong engineering judgment, hands-on design capability, clear communication, and the ability to balance technical performance, safety, remote maintainability, manufacturability, schedule, and cost in a fast-moving environment. Specific responsibilities may include: - Serve as Oklo's technical expert for high-temperature piping, pressure vessels, pressure boundaries, and their supporting components within the OFRF. - Translate process temperatures, pressures, chemistry, flow conditions, vacuum and inert-gas requirements, operating cycles, and upset conditions into the piping and vessel design basis, applicable codes, load combinations, service life, and acceptance criteria. - Perform and review piping stress and flexibility analyses for sustained, thermal, pressure, seismic, displacement, and other applicable loads, including equipment nozzle loads and support reactions.

- Perform and review pressure vessel analyses for internal and external pressure, local loads, nozzle loads, thermal gradients, buckling, fatigue, creep, and cyclic service, including design-by-analysis when appropriate. - Perform and review steady-state and transient thermal analyses addressing heat loss, insulation, heat tracing, temperature gradients, heat-up, cooldown, and abnormal thermal conditions. - Select and qualify materials for high-temperature and corrosive service, considering molten-salt compatibility, oxidation, thermal aging, creep, fatigue, radiation exposure where applicable, weldability, and fabrication constraints. - Design and review vessels, piping, nozzles, flanges, closures, transitions, supports, anchors, restraints, expansion joints, bellows, penetrations, and other pressure-boundary components. - Define piping layout, support, restraint, slope, drainability, isolation, inspection, and access requirements needed to manage thermal expansion and support safe operation and maintenance. - Coordinate piping and vessel interfaces with process equipment, hot-cell penetrations, confinement boundaries, structures, utilities, and instrumentation; incorporate remote connection, inspection, isolation, removal, and replacement provisions where personnel access will be limited. - Develop and review calculations, specifications, piping material classes, line lists, vessel data sheets, drawings, fabrication details, and technical requirements. - Review supplier and subcontractor calculations, models, drawings, material selections, weld details, fabrication procedures, and inspection plans; provide technical direction and resolve piping and vessel design issues. - Establish fabrication and quality requirements, including material traceability, welding, heat treatment, dimensional control, nondestructive examination, pressure testing, leak testing, and final acceptance. - Develop procurement specifications, statements of work, technical bid evaluations, and supplier acceptance criteria for piping and vessel packages.