Mechanical Equipment Engineer - Energy

ALTEN UK is seeking a Mechanical Equipment Engineer to join our engineering team s role will support the detailed design, commissioning and testing of mechanical equipment for active nuclear facilities, ensuring safety, compliance and operational excellence. This is a unique opportunity to work on complex, safety‑critical systems including pumps, valves, HVAC systems, pipework and ancillary plant equipment, supporting post‑operational testing and cleanout activities.

• Take responsibility for the design, installation, and testing of mechanical plant systems, working collaboratively with multidisciplinary engineering teams.
• Lead detailed mechanical design activities, producing high‑quality drawings, calculations and specifications.
• Support works testing, commissioning and verification of installed equipment performance.
• Troubleshoot and resolve mechanical system issues as they arise.
• Interface with electrical, instrumentation, process and civil engineering teams.
• Ensure compliance with nuclear regulations, safety standards and quality assurance requirements.
• Support post‑operational activities, including plant cleanout and preparation for maintenance or decommissioning operations.
• Contribute to risk assessments, method statements and safety documentation.
• Mentor junior engineers and support team development.

• Degree in Mechanical Engineering or equivalent professional qualification.
• 5+ years’ experience in detailed mechanical design, ideally in nuclear, defence or other regulated safety‑critical industries.
• Hands‑on experience with mechanical plant equipment, including pumps, valves, HVAC systems, pipework and ancillary plant.
• Familiarity with works testing, commissioning and post‑operational cleanout procedures.
• Strong understanding of mechanical design standards and industry regulations (ASME, BS, EN).
• Proficiency in CAD/design software (AutoCAD, Inventor, Solid Works or equivalent).
• Excellent communication skills and experience producing technical documentation.
• Ability to work both independently and collaboratively in multidisciplinary teams.

• Previous experience in nuclear or regulated environments.
• Knowledge of plant maintenance, lifecycle management or decommissioning.
• Experience delivering projects in a hybrid working environment.

• A personalised career path and a rewarding management style.
• A chance to work on the most exciting engineering projects and technologies with premium customers.
• Diverse range of engineering projects and industries.
• Competitive salary.
• Private medical and travel insurance.
• Pension scheme.
• Cycle‑to‑work scheme and other benefits.
• Social atmosphere, regular gatherings and team building.

Security Clearance:
This role requires you to have or be willing to go through Security Clearance. Candidates will be asked to complete a Baseline Personnel Security Standard. If you are unable to meet this or the associated criteria, your employment may be delayed or rejected.

Seniority Level: Associate |

Employment Type:

Full‑time | Job Function:
Consulting.