Costain Group
Principal Mechanical Engineer (Nuclear Mechanical Handling)

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Following a number of project and long term framework wins in the Nuclear industry, including Urenco, we are seeking a Principal Mechanical Engineer to support and deliver key elements of design work on projects, primarily through the management of technical resources to deliver on company and client promises.
Costain’s multi-disciplinary engineering and design team delivers comprehensive design solutions across a range of UK Infrastructure sectors - Energy, Defence & Nuclear, Water, Rail, Roads and Integrated Transport. The team covers the full project lifecycle from feasibility and concept through to detailed design and construction support. We focus on the delivery of sustainable, future ready and safe-by-design outputs with a strong constructability ethos.
Typical deliverables and activities for the Mechanical Engineering team include:
- Specifications and Datasheets for Mechanical Equipment
- Enquiry and Purchase Requisitions for Mechanical Equipment Packages.
- Technical Bid Evaluations for Mechanical Equipment Packages.
- Vendor documentation review and FAT attendance for Mechanical Equipment Packages.
- Mechanical Handling and Lifting equipment Specification and design
- HVAC & Building Services design
- Plant and Mechanical Equipment Layout
- Pumping system calculations
- Pressure Equipment design calculations and Mechanical Equipment stress analysis
As a Principal Mechanical Engineer, you will be responsible for delivering key elements of design work on projects, primarily through the management of technical resources to deliver on company and client promises.
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This role requires significant technical interface management between delivery teams, driving progress, ensuring compliance and quality, and resolving complex challenges. You may act as the single point of contact for the project discipline team, hold budget and resource responsibility, and maintain line management duties while executing hands-on design production, checking, and approval.
This role will make a key contribution to development of Costain’s capability in the specialist area of Nuclear Mechanical Handling to support exciting projects for a number of clients based in North and North West England.
Hybrid role typically involves working three days a week in the Manchester or in our clients office in Cheshire with a flexible approach to home working to promote wellbeing.
Costain helps to improve people’s lives with integrated, leading edge, smart infrastructure solutions across the UK’s energy, water, transportation and defence markets. We help our clients improve their business performance by increasing capacity, improving customer service, safeguarding security, enhancing resilience, decarbonising and delivering increased efficiency. Our vision is to be the UK’s leading smart infrastructure solutions company. We will achieve this by focusing on blue chip clients whose major spending plans are underpinned by strategic national needs, regulatory commitments, legislation or essential performance requirements. Our offer our clients leading edge solutions that are digitally optimised through the following five services which cover the whole lifecycle of their assets: future-shaping strategic consultancy; consultancy and advisory; digital technology solutions; asset optimisation and complex programme delivery. Our culture and values underpin everything we do.


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Costain appreciate the time and effort taken when applying for one of our positions but, due to the high volume of responses, we are unable to provide individual feedback on candidates at application phase.
We do share individual feedback following an interview.
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