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Long lead item


Long lead item refers to the equipment, product or system that is identified at the earliest stage of a project to have a delivery time long enough to affect directly the overall lead time of the project.


The long lead items are common in the oil & gas and petrochemical industry because of the complexity of the supply chain used by the end users to design and execute their projects.

In the oil & gas and petrochemical sector, the end user outsource the procurement of the equipment, product and system to the engineering, procurement and construction (EPC) contractors.

These EPC contractors have been involved in the project at the last stage for execution, after the project conceptual study, feasibility study and the front end engineering and design (FEED).

When the end user goes to execution it expects the awarded EPC contractors to execute the construction of the project as fast as possible.

That is where the conflict comes with the long lead items.

Some equipment, product or system have a normal delivery time which is too long to be outsourced through the EPC contractors.

Typically large compressors, turbines, generators, control systems may have 12 to 24 months delivery times for a project to be executed in 36 months.

Even if the delivery time of these equipment may be shorter than the whole project, it must be considered the additional time for the EPC to organize the tenders and selection of the vendors which may take 6 to 12 months, plus the time to install these equipment when delivered on site.

In the best case if these equipment would be bought by the EPC contractors they should add at least 12 months to the overall project schedule.

To avoid this delay, these equipment are treated as long lead items meaning that they will not follow the same supply chain as the other equipment.

These long lead items shall be defined at the detailed design stage, or FEED, and the end user will conduct the bidding process in parallel of the EPC contracts tenders.

The engineering company in charge of the FEED or the Project Management Consultant (PMC) is normally supporting the end user in this process.

The goal is to synchronize the final decision to select the vendors of the long lead items previously the choice of the EPC contractors.

To do so the end user places a letter of intent (LOI) to selected vendor of the long lead item and inform the leading EPC contractor that in case of being awarded it will have to endorse this LOI and convert it into a formal order.

The benefit is for the end user and its long lead item vendor to work in parallel of the EPC contractors, so that the long lead item shall be delivered and installed in line with the EPC overall schedule.

For more information and data about oil and gas and petrochemical projects go to Project Smart Explorer

11 thoughts on “Long lead item”

  1. secure at our expense the right for the buyer to continue using the delivery items, or, we will modify the delivery items in a manner which is reasonable for the buyer and which eliminates the breach of property rights.

  2. In an EPCM contract, the FEED (Basic Engineering) has been done already. When the owner/customer finally decides on the contractor, when should the contractor start ANY activity for the LLIs, even before the detailed engineering starts? This can be done in cooperation with the owner, because as you know in EPCM the contractor is doing this work on-behalf of the owner.

    Thanks in advance for your help.

    1. Dear Bradley,
      Thank you for your comment.
      Usually the basic design done at FEED stage is enough to size the different components under Long Lead Items procurement.
      In fact, by nature, Long Lead Items have to be in the pipe before the detailed engineering starts, meaning before the main contractor being awarded the EPC contract. Thus, LLIs are directly handled by the owner/operator of the futur facility and LLIs specifications have to be integrated by the engineering companies bidding on the EPCM contract for their design.
      I hope it helps

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