Mechanical Design Engineer Role Title: Mechanical Design Engineer (Level III / Equivalent) Location: Rockville, Maryland Working Pattern: 4-5 days onsite Travel: Up to 10% About the Role We're partnered with a pioneering advanced nuclear energy company at the forefront of developing the next generation of clean, reliable power. As the energy landscape evolves, this organization is helping deliver dependable, always-on carbon-free electricity that supports economic growth while driving the transition to a more sustainable future. We are seeking a seasoned, hands-on Mechanical Design Engineer to spearhead the development of heavy, complex physical hardware and integrated systems. This is not a purely analytical or desk-bound role. We are looking for an execution-focused engineer who takes pride in physical delivery. You will guide projects through their entire lifecycle-from initial conceptual sketches and detailed engineering through to manufacturing, shop-floor assembly, rigorous testing, and final field commissioning. The ideal candidate has a proven track record of bringing tangible hardware from blueprint to reality, collaborating directly with fabrication shops, and solving real-world mechanical integration challenges in code-governed industries. Key Responsibilities Concept to Completion: Develop innovative mechanical concepts, robust layouts, and detailed engineering solutions for large-scale systems, complex structures, and heavy mechanical assemblies. Full-Lifecycle Ownership: Take uncompromising personal ownership of mechanical hardware, driving accountability from preliminary design all the way through fabrication, assembly, and testing. Documentation & Modeling: Produce accurate 3D CAD models, detailed fabrication drawings, geometric dimensioning and tolerancing (GD&T), and comprehensive engineering documentation compliant with industry codes. Engineering Analysis: Perform rigorous hand calculations and finite element analyses (FEA) to validate structural integrity, pressure containment, kinematics, and thermal performance to support critical design decisions. Supply Chain Collaboration: Partner closely with external suppliers, machine shops, and internal manufacturing teams to ensure designs are optimized for manufacturability, cost-efficiency, and seamless assembly under strict quality standards. Testing & Troubleshooting: Support prototype assembly, factory acceptance testing (FAT), site acceptance testing (SAT), qualification milestones, and rapid resolution of shop-floor or field design issues. Multidisciplinary Integration: Lead and participate in formal design reviews (PDR/CDR), verification activities, and cross-functional coordination to manage complex mechanical interfaces. What We're Looking For Education: Bachelor's degree in Mechanical Engineering, Aerospace Engineering, or a closely related technical discipline. Experience: Typically 5+ years of progressive mechanical design engineering experience in a fast-paced, hardware-focused environment. Code & Regulatory Expertise: Strong working knowledge and practical application of ASME codes and standards (such as ASME BPVC Section III or Section VIII, and ASME B31.1 or B31.3 piping codes) for design, analysis, and manufacturing. Hardware Provenance: Demonstrable portfolio or work history showing personal ownership of physical hardware taken successfully through the manufacturing and test phases. CAD Proficiency: Advanced proficiency in industry-standard 3D CAD platforms (e.g., Siemens NX, SolidWorks, Creo/Pro-E, CATIA, or Autodesk Inventor). Technical Acumen: Strong command of core mechanical engineering principles, mechanics of materials, machine design, and engineering mathematics. Communication: Exceptional verbal and written communication skills with the ability to bridge the gap between high-level project management, shop-floor technicians, and executive stakeholders. Preferred Experience & Background Experience in one or more of the following complex, high-stakes environments will make your application stand out: Heavy industrial or large-scale engineered capital equipment Power generation, thermal systems, and advanced energy infrastructure Regulated sectors such as nuclear engineering, defense, or aerospace Pressure vessels, high-pressure piping, pumps, valves, and fluid process equipment Large metallic structures, weldments, and heavy mechanical handling systems Turbomachinery, compressors, or high-speed rotating equipment Marine, offshore, or subsea engineering applications