Project Completion: DHT & H2 Refinery Design & Fabrication

From Unbuilt Design to Fully Engineered Reality

3D Engineering Surveys Ltd (3DES) has successfully delivered a landmark engineering project in Bangladesh — transforming incomplete pre-design documentation into a fully coordinated, build-ready refinery design package for two critical process units: a Diesel Hydrotreater (DHT) and a Hydrogen (H2) unit.

The Challenge: Engineering from Incomplete Legacy Documentation

When 3DES was first commissioned on this project, the client had already procured equipment for both refinery process units — but construction had never commenced. What existed was a set of pre-design documents: enough to confirm what had been purchased, but far from sufficient to build from.

The challenge was clear — and significant. Without a complete, intelligent 3D model and a robust engineering design behind it, construction could not proceed safely or efficiently. The risk of costly clashes, rework, and site-level complications loomed large.

3DES accepted the commission not merely as a modelling exercise, but as a full end-to-end engineering engagement.

The Approach: Intelligent 3D Modelling as the Foundation

The project began with the development of a comprehensive intelligent 3D model using AVEVA E3D, one of the industry's leading plant design platforms. Every element of both process units was modelled in full — equipment, structures, pipe racks, cable trays, piping systems, supports, and all associated infrastructure. Deliverables were issued in both AVEVA E3D and Navisworks formats to ensure seamless integration with the client's own systems and workflows.

This digital-first approach proved decisive. With a high-fidelity model in place, the 3DES team was able to carry out thorough clash detection and constructability reviews — identifying a series of critical design conflicts and layout issues before a single component was installed on site.

The value of this work cannot be understated. Catching design conflicts at the modelling stage is exponentially less costly than discovering them during construction. By surfacing these issues early, 3DES significantly reduced the client's exposure to rework, delays, and cost escalation — protecting both schedule and budget.

Detailed Engineering Design

With constructability confirmed, 3DES proceeded to deliver the complete detailed engineering design for both units. This encompassed:

Piping Systems Full pipe routing was designed and documented, establishing safe, efficient, and code-compliant flow paths throughout both process units.

Pipe Racks and Structural Steelwork Structural design for pipe racks and supporting steelwork was developed to accommodate the routed piping systems, ensuring structural integrity and maintainability.

Piping Support Design A comprehensive piping support package was produced, addressing load transfer, thermal movement, and equipment nozzle loads across the full extent of both units.

Piping and Structural Stress Analysis Detailed stress analysis was carried out across all critical piping systems and structural members. All work was verified for compliance against applicable international codes and client-specific engineering specifications, with formal analysis reports issued as part of the deliverable package.

2D Drawing Production

In parallel with the engineering design, the team produced a full suite of construction-ready 2D drawings, including:

• Intelligent isometric drawings for all piping systems

• Structural General Arrangement (GA) drawings

• Pipe support fabrication drawings

All drawings were produced to the standards required for direct use in fabrication and construction, minimising the need for further interpretation or revision on site.

Bill of Quantities (BOQ)

A comprehensive Bill of Quantities was prepared covering the full material scope of both units, including:

• Pipes, fittings, and valves

• Pipe rack and equipment structures

• Supports and cable tray systems

• Gaskets, bolts, nuts, and all associated bulk materials

This BOQ provides the client with a reliable foundation for procurement, cost estimation, and construction planning.

Project Impact

The DHT & H2 Refinery project stands as a strong example of what modern digital engineering can achieve when applied rigorously from the outset. By building an intelligent 3D model before committing to construction, and by integrating clash detection, detailed design, stress analysis, and documentation into a single coordinated workflow, 3DES delivered something more than drawings and models — it delivered confidence.

The client received a fully engineered, fully validated, build-ready design package for two complex refinery process units, developed from documentation that was never intended to support construction on its own.

This project reflects the core capability that defines 3DES: the ability to take on technically demanding, high-stakes engineering challenges and deliver outcomes that are precise, compliant, and construction-ready.

For more information about 3DES capabilities in intelligent 3D modelling, detailed engineering design, and constructability analysis, please contact our team.

For inquiries, please contact sales@3dengineeringsurveys.com

3D Engineering Surveys Ltd

1 The Court Yard, New North Road, Exeter EX4 4EP

sales@3dengineeringsurveys.com

www.3dengineeringsurveys.com