Job title: Principal Mechanical Engineer Job Type: Contract IR35 Status: Inside IR35 Start date: As soon as possible subject to security clearance Duration: 12 months Salary/ Pay rate/ Benefits: £60-£69 per hr *Umb Location: Warrington / Hybrid - 2 or 3 days per week working from the office. Hours of work: 37-40 hours per week Mon-Fri About the Role: 6‑month design development phase, with continued involvement during procurement We are seeking an experienced Principal Mechanical Engineer to lead the mechanical engineering discipline across a major project, with responsibility for delivering high‑quality design outputs, managing technical interfaces, and guiding a team of engineers. You will act as the primary authority for mechanical engineering within the project and work closely with multidisciplinary teams, clients, and stakeholders to ensure successful delivery of all mechanical design requirements This role involves taking a lead position in the development of key design deliverables during an intensive design phase, followed by support during subcontractor procurement and oversight of equipment manufacture. Experience with glovebox design is highly desirable. Key Responsibilities: Act as the lead authority for all mechanical engineering activities on the project Lead and coordinate single‑ or multi‑discipline engineering teams. Produce and review core design deliverables, including drawings, flow diagrams, and calculations. Ensure designs meet applicable standards, regulations, and customer requirements Manage technical interfaces, resolve engineering issues, and oversee change control. Prepare high‑quality technical documentation, safety reports, and quality plans Present designs at reviews, client meet Support bids with estimates, scope definition, and programme logic Support bids with estimates, scope definition, and programme logic Mentor junior engineers and maintain strong working relationships with client teams The candidate must have the following skills, experience & qualifications: Minimum 8 years' experience in the nuclear industry. At least 3 years at Senior Engineer level. Degree in Mechanical Engineering Strong knowledge of mechanical design standards, regulations, and codes Proven experience producing design deliverables and Technical Files Please note the successful candidate would be required to undergo BPSS security clearance prior to starting. Interested in this position? please click "apply now" We try to respond to all applicants, but sometimes this is not possible due to high volumes of applications; if you have not heard from us within 14 days, regrettably it means you have been unsuccessful on this occasion. Since 1978, Rullion has been securing exceptional candidates for a range of clients; from large well-known brands, to SMEs and start-ups. As a family-owned business, Rullion's approach is credible and honest, focused on building long-lasting relationships with both clients and candidates. Rullion is a forward-thinking recruitment company that specialises in providing a wide range of talent consultancy services to a diverse client base; from small start-ups to large household names. We celebrate and support diversity and are committed to ensuring equal opportunities for both employees and applicants. Rullion celebrates and supports diversity and is committed to ensuring equal opportunities for both employees and applicants