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HomeCareer Senior Mechanical Designer

Our Vacancy

Senior Mechanical Designer

  • Nuclear
  • Permanent /
  • Warrington
  • United Kingdom
  • 10/05/25
  • On site

Assystem is an international company with one mission: accelerate the energy transition around the world.


Every day, our 7,750 switchers located in 12 countries (Europe, Middle East, Pacific Asia & Africa) connect their six thousand billion neurons to tackle the task of the century: switching to low-carbon energy.


We are a collective committed to the actors who are making the energy switch. Sharing our knowledge, expertise and values allows us to innovate and think differently about the energy transition.


Drawing on more than 55 years’ experience in highly regulated sectors subject to strict security and safety requirements, we provide our customers with engineering and project management services, as well as digital services and solutions to optimize the performance of complex infrastructure projects throughout their life cycle. The Group is currently ranked second in the world for nuclear engineering.


To ensure a viable, efficient, and reliable energy future for all.


Job Description

Senior Mechanical Designer

Warrington

Permanent / Contract

Delivery of Mechanical asset care scope across a portfolio of Projects, initially focussing on the THORP Cooling Towers Dosing System Project which will involve the specification of a new COTS dosing skid, and the design of a Piping system to integrate the skid into the existing Cooling Tower infrastructure.

To produce engineering design work packages (specification, drawings, analysis, verification or assessment of engineering) that satisfy the legal and functional requirements along with the associated performance conditions to the agreed time, cost and quality.

My profile

🎓 Degree in Mechanical Engineering with a minimum of 2 years’ design delivery experience
OR
📘 Other qualification such as HNC/HND with 5+ years’ design delivery experience

⚙️ Experience in highly regulated industries, preferably the nuclear industry

✅ Proven track record of delivering safe, fit-for-purpose, fully integrated and operable design solutions that meet product requirements

💻 Qualified and experienced user of:

  • AutoCAD

  • Autodesk Inventor

  • Autodesk Vault

📄 Experience producing key design deliverables, including:

  • Product Requirements Specifications

  • Technical Reports

  • Calculations

  • Technical Drawings & Layouts

  • Installation Method Statements

  • Risk Assessments

  • Design Substantiation

🧪 Mechanical piping design experience, with knowledge of relevant standards and legislation (e.g., ASME B31.3, PER, PSSR)

🛠️ Familiarity with machine design and mechanical handling, including legislation such as:

  • The Supply of Machinery (Safety) Regulations

  • LOLER

  • PUWER

📏 Knowledge of British and ISO Standards

🤝 Strong ability to liaise with stakeholders across technical and non-technical backgrounds

👥 Experience in multi-disciplinary, integrated design delivery teams

🔍 Skilled in peer reviewing/checking:

  • Reports

  • Proposal & detail drawings

  • Supporting calculations

Security clearance:

Due to the nature of work to be undertaken applicants will be required to meet certain residency criteria in order to attain a minimum level of UK security clearance if not already security cleared to a minimum SC level.

We are committed to equal treatment of candidates and promote, as well as foster all forms of diversity within our company. We believe that bringing together people with different backgrounds and perspectives is essential for creating innovative and impactful solutions. Skills, talent, and our people’s ability to dare are the only things that matter !. Bring your unique contributions and help us shape the future.

Are you a prospective or recent graduate?

Assystem offers you the opportunity to join our Switch to Grow UK Graduate Scheme, where you’ll gain hands on experience in engineering, digital services, and project management by working on some of the world’s most critical energy projects.

Be part of the challenge of the century; accelerating the switch to low carbon energy!

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