Senior Mechanical Design Engineer (Fluid Systems)

Company: Assystem
Apply for the Senior Mechanical Design Engineer (Fluid Systems)
Location: Sunderland
Job Description:

Overview

As a Senior Mechanical Design Engineer, you will develop fluid systems within a nuclear-focused engineering context. You will collaborate with multi-disciplinary teams to deliver safe, compliant designs and maintain CAD/BIM documentation. The role offers opportunities to influence layout, modelling, and design reviews across the project lifecycle. You will work in a safety-conscious environment with a strong emphasis on quality, timeliness, and collaborative problem solving. This position combines technical leadership, hands-on design work, and close coordination with stakeholders to shape complex infrastructure.

Pay / Benefits

  • hybrid work: 1-2 days remote per week
  • attractive social benefits including holiday bonuses
  • ongoing training and numerous career opportunities
  • internal promotion culture (70% managers promoted internally)
  • employee committee engagement
  • diversity and equal opportunity commitment

Responsibilities

  • Develop 2D CAD drawings, including PFDs and P&IDs
  • Prepare 3D CAD/BIM models, plant layouts, piping design, isometrics, MTO, GA drawings and sketches
  • Perform layout optimisation across design phases
  • Participate in 3D model reviews, layout reviews, design reviews and technical meetings
  • Ensure compliance with design safety factors, tolerances, standards, codes and legislation
  • Collaborate with multi-disciplinary teams to ensure coordinated design
  • Maintain design process records and CAD/BIM documentation databases
  • Report status to management and meet targets regarding quality, time and budget
  • Support and mediate solutions with all stakeholders aligned
  • Ensure adherence to H&S policies and project Quality requirements

Key requirements

  • Previous experience as Mechanical Design Engineer or similar
  • Ability to work within engineering team to realise designs
  • Familiarity with 2D CAD systems (AutoCAD) for drawing creation
  • Familiarity with 3D CAD/BIM systems (Revit, Inventor, Solidworks, Solid Edge, Siemens NX, PDMS, AutoCAD Plant 3D) for model and drawing creation
  • Professional qualification in an engineering related field
  • SC Clearance or capable of achieving it
  • Good communication skills, written and oral
  • Focus on delivering quality output to time and budget
  • Integrity and ability to instil it in others
  • 2D CAD (AutoCAD)
  • 3D CAD/BIM (Revit, Inventor, SolidWorks, Solid Edge, Siemens NX, PDMS, AutoCAD Plant 3D)
  • PFD and P&ID development

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Posted: October 10th, 2026