Detailed Engineering Design (DED) is an engineering stage that produces complete and detailed technical documents so that a facility, factory, building, or infrastructure can be constructed, manufactured, installed, tested, and operated in accordance with the project's technical, safety, quality, cost, and schedule requirements.
At this stage, all concepts and basic designs (Conceptual Design and FEED) are translated into working drawings (Issued for Construction/IFC), technical specifications, engineering calculations, bill of materials, and procurement documents ready for use by contractors and vendors.
Purpose of Detailed Engineering Design
The main objectives of DED include:
* Producing a constructible design.
* Reducing the risk of design changes during construction.
* Ensuring compliance with codes, standards, and regulations.
* Serving as a basis for material and equipment procurement.
* Supporting more accurate cost estimates.
* Simplifying the construction, commissioning, and operation processes.
Scope of Detailed Engineering Design
The DED involves all engineering disciplines working in an integrated manner.
1. Process Engineering
Outputs include:
* Process Flow Diagram (PFD)
* Piping & Instrumentation Diagram (P&ID)
* Heat and Material Balance
* Equipment Data Sheet
* Process Calculation
* Utility Consumption
* Process Description
* Cause and Effect Diagram
2. Mechanical Engineering
The scope of work includes:
* Equipment Specification
* Vessel Design Review
* Pump Selection
* Compressor Selection
* Heat Exchanger Specification
* Tank Design
* Mechanical Data Sheet
* Rotating Equipment Specification
* Static Equipment Specification
Outputs:
* Mechanical Drawings
* General Arrangement
* Equipment Layout
3. Piping Engineering
This is one of the largest tasks in the DED stage.
Deliverables:
* Plot Plan
* Equipment Layout
* 3D Models
* Piping Layout
* Isometric Drawing
* Pipe Support Drawing
* Material Take-Off (MTO)
* Line List
* Valve List
* Tie-in List
* Pipe Stress Analysis
* Pipe Support Calculation
4. Civil Engineering
Includes:
* Site Development
* Earthworks
* Drainage
* Road Design
* Foundation Design
* Retaining Walls
* Underground Utilities
* Concrete Drawing
Deliverables:
* Civil General Arrangements
* Foundation Drawing
* Grading Plan
*Drainage Drawing
5. Structural Engineering
Main output:
* Steel Structure Design
* Structural Calculation
* Pipe Rack Design
* Building Structure
* Connection Details
* Anchor Bolt Design
* Fabrication Drawing
* Erection Drawing
6. Electrical Engineering
Scope of work:
* Single Line Diagrams
* Load Flow Study
* Short Circuit Study
* Cable Sizing
* Cable Routing
* Grounding System
* Lighting Design
* UPS System
* Transformer Selection
* Motor Control Center (MCC)
* Schedule panel
Deliverables:
* Electrical Layout
* Cable Schedule
* Lighting Layout
* Grounding Layout
7. Instrumentation & Control Engineering
Includes:
* Instrument Index
* Instrument Datasheet
* Loop Diagrams
* Hook-up Drawing
* Junction Box Layout
* Cable Schedule
* I/O List
* PLC/DCS Architecture
* Control Philosophy
* Alarm Philosophy
* Cause & Effect Matrix
8. Safety Engineering
Work:
* Fire Fighting System
* Fire Water Network
* Fire Alarm System
* Gas Detection
* Hazardous Area Classification
* HAZOP Close-out
* SIL Verification
* Escape Routes
* Passive Fire Protection
9. Telecom & ICT Engineering
If needed:
* CCTV
* Public Address System
* Telephone System
* LAN System
* Fiber Optic
* Access Control
* Data Network
DED Main Deliverables
The resulting documents usually include:
Engineering Documents
* Base Design
* Engineering Calculations
* Technical Specifications
* Design Reports
* Material Specifications
Engineering Drawings
* General Arrangement (GA)
* Plot Plan
* Equipment Layout
* Foundation Drawing
* Structural Drawing
* Piping Layout
* Isometric Piping
* Electrical Layout
* Instrument Layout
* Hook-up Drawing
* Cable Routing
* Underground Drawing
Procurement Documents
* Material Requisition (MR)
* Technical Bid Evaluation (TBE)
* Vendor Data Requirements
* Material Take-Off (MTO)
* Bill of Quantities (BOQ)
Vendor Documents
* Vendor Drawing Review
* Vendor Data Review
* Vendor Print Approval
Construction Documents
* Issued for Construction (IFC) Drawings
* Construction Work Package
* Installation Detail
* Erection Procedure
* Construction Specification
DED Implementation Stages
1. Review of Conceptual Design and FEED documents.
2. Collect field and technical data.
3. Prepare the design basis.
4. Engineering calculations for each discipline.
5. Develop a 3D model.
6. Create detailed drawings.
7. Interdisciplinary Check.
8. Design review and verification.
9. Client approval.