EPC can mean many things to many people; to some Europeans it could be: European Payments Council, European Policy Centre, or even European Patent Convention, but to us Engineers, EPC stands for Engineering, Procurement, and Construction; three main activities necessary for the execution of any industrial project.
For starts, the engineering phase usually involves preparing designs and equipment datasheets, dealing with specifications, and preparing “lists”. Lists which contain all the materials and equipment needed for the project and are later used by the procurement department. The procurement department then, purchases everything according to the lists and specifications agreed upon by the contractor (the engineering company) and the client (the owner of the industrial facility). Finally, construction work begins using all the materials and equipment purchased and according to the designs prepared by the engineering department.
But before all that could happen, several steps need to be taken. The first step is the Business Planning Phase, which is done by the client; it involves defining the business opportunity, conducting a technical assessment, and undergoing an economic evaluation, to name a few. The other steps which are done by the engineering company include:
1. BED – BASIC ENGINEERING DESIGN
BED, also known as pre-feed is basically a conceptual design done to confirm the feasibility of a project, select technology, refine cost estimate with +/-30% accuracy, and develop process design among others. It typically has a process engineering focus with major equipment identified from an electrical, mechanical, and instrument perspective. Different engineering companies, cover different steps; for instance, Technip’s BED includes:
- Conceptual process studies (material balances, process flowsheets,…) and preliminary plot plan.
- Preliminary Piping and Instrument Diagrams.
- Definition and sizing of main equipment resulting in process specifications.
- Specification of effluents.
- Definition of control and safety devices.
- And, generally speaking, all the basic studies required to support a Basic Engineering Design Package (BEDP) containing all data needed by a competent contractor to perform the Detail Engineering.
2. FEED – FRONT END ENGINEERING DESIGN
The economic viability of a project is assessed during the BED and FEED stages; both of which are conducted prior to taking any investment decisions. However, unlike BED, FEED provides a more accurate cost estimate with a margin of +/-10%. To obtain that accuracy though, the Bill of Quantities (BOQs) of materials need to be taken into account. And that can only be determined from design drawings and material-take-off. An example of FEED can be seen below:
- Cost & weight estimation
- Safety and control system philosophies
- Equipment sizing and specifications for utilities
- Material Take-Off lists (MTO’s) and specifications of long lead items
- Installation procedures
- Preparation of EPC tender material
- Design verification
[SOURCE: Ramboll’s FEED]
In simple words, at this stage, a conceptual choice is being transformed from an idea to viable solution that can eventually be constructed. Hence, the objective of FEED, aside from a refined cost estimate is to provide all the technical requirements needed for detail design so that the EPC work can commence. Technical requirements include: specifications, scope of work, and drawings. According to Chiyoda Corporation, the duration of the FEED phase is roughly 1 year in the case of large projects such as the development of an LNG plant.
3. DETAIL DESIGN
Detail design is the first step in the EPC phase also known as the execution phase of a project. The FEED developed earlier acts as a basis for this stage. Unlike FEED, during detail design, equipment is purchased from vendors, allowing equipment data (for ex: dimensions) to be retrieved and integrated into the plant design. Usually at the FEED stage, plant design is merely based on dimension and power consumption estimates of equipment. Lastly, this stage also includes specifying all plant equipment and preparing construction drawings. Check out Technip’s DETAIL DESIGN as an example:
- Purchasing of equipment, main and bulk.
- Thermal rating of heat exchangers.
- Development of Piping and Instrument Diagrams released for construction.
- Development of detailed piping drawings, including isometrics and stress calculations.
- Development of detailed drawings related to instrumentation, electrical facilities and civil works.
- Management of vendor drawings.
- Cost and schedule control.
- Start-up procedures.
- And, generally speaking, all the studies to be performed before construction of the plant.
It is important to note that engineering work is not a linear process but an iterative one. As more data are made available or changed, the design may be revised. For example, a plant layout may be revised when equipment design data by vendors are made available.
In this post, the engineering services offered by Technip and Ramboll have been featured; however, there are similar engineering services offered by other EPC companies, such as: Samsung Engineering, Petrofac, JGC Corporation, McDermott, and Fluor Corporation, among others.
About the blogger: Yasmin Pascual Khalil is a chemical engineer with an undergraduate degree from Curtin University and soon a master’s degree from Ecole Nationale Supérieure Du Pétrole Et Des Moteurs (IFP School) with a specialization in polymers and refining and petrochemical processes. Currently, she is a contributing editor at IEEE Engineering360 and a process engineering intern at Technip, France. In case of inquiries, feel free to contact her via email at firstname.lastname@example.org.