Long Lead Items: Identify, Prioritise and Order Them Early

Long lead items are equipment that takes longer to engineer, build, test and deliver than your schedule allows if you order it at the usual point. Find them early by putting a realistic lead time and a need date against every line of the equipment list, then rank them by float, criticality and how many suppliers could make them. Order the critical few ahead of the rest, by reserving a slot, issuing a limited notice to proceed, buying material in advance or ordering with engineering holds.

Why this matters now

Electrical equipment shows the problem most clearly. In the US, a large power transformer (100 MVA or more) could be ordered with a lead time of under a year before the pandemic; in 2024 the Department of Energy reported 36 months as commonly quoted, and up to 60 months [1]. The IEA puts large power transformers at up to four years, with average lead times almost doubled since 2021 [2]. Wood Mackenzie had US power transformers averaging 128 weeks and switchgear 44 weeks in the second quarter of 2025 [3], and transmission owners in Great Britain report up to 36 months for gas insulated switchgear [4].

A plant that needs a new grid connection or substation buys the same kinds of equipment, usually smaller. And the decisions come early: as our review of UK and Ireland process plant projects noted, vendor lists for long lead equipment are usually shaped during front end design. Find long lead items late, and a factory queue sets your start up date.

What makes an item long lead

A supplier's quoted weeks are only part of the clock. The real lead time runs from your first enquiry to the item on its foundation: enquiry and approval, supplier engineering and drawing review, materials, a factory slot, manufacture, testing and shipping. The US Department of Energy describes much the same chain for large transformers, with extra delay when the order queue is backed up or a key input such as electrical steel is scarce [1]. An item is long lead when the whole chain is longer than the gap between your normal ordering point and the date it is needed.

Usual candidates on process plants:

• Power transformers and high voltage switchgear, as above.
• Large compressors and rotating machines. Burckhardt Compression, a reciprocating compressor maker, shows 10 to 22 months to engineer and manufacture a compressor system on a typical project [5].
• Large vessels and columns in special alloys, which often wait on plate and forgings from the mill.
• Large valves and forgings, where the foundry or forge queue can set the date.
• Control systems, where configuration and testing often wait for frozen design data.

How to identify long lead items

Start from the equipment list as soon as one exists, not from the purchasing plan.

1. Put a lead time on every line. Ask for it in budgetary enquiries, with its basis: ex works or delivered, what drives it, and whether it runs from order or from drawing approval, which our guide to budgetary and firm quotes shows are different clocks.
2. Set a need date. On a skid based plant, skid mounted items are needed at the skid builder's shop, often months before site.
3. Work back. The need date minus the full lead time gives the latest order date, and your own enquiry and approval time comes off that again. Anything that must be ordered before design freeze or sanction is long lead.
4. Refresh at each stage. Lead times move: Wood Mackenzie saw the US average for power transformers fall 10 weeks in one quarter [3].

How to prioritise them

Not every long lead item justifies early spending. Ask three questions:

• How much float is left? The weeks between the earliest date you could order and the latest order date. Negative float means it is already late.
• Is it on the critical path? A transformer that holds up energisation matters more than a spare pump.
• How many suppliers could make it in time? A single qualified source moves an item up the list.

That gives four groups: act now (long lead, critical, few sources), secure and watch (long lead, with float or several sources), expedite (short lead but critical) and normal procurement. Our guide to CAPEX procurement strategy shows where this fits in your wider package strategy.

Ways to order long lead items early, and the risks

Four routes, from lightest commitment to heaviest:

• Reserve a manufacturing slot. Pay a fee or deposit to hold factory capacity before the specification is complete. In Great Britain, Ofgem's Advanced Procurement Mechanism lets transmission owners book supply chain capacity before projects are assessed and funded; in October 2026 Ofgem approved about £835m (2023/24 prices) under it, about 20% of the expected contract costs [4].
• Issue a limited notice to proceed. A short instruction, sometimes a letter of intent, authorising named work such as engineering, up to a capped sum, before the full contract. Give it a scope, a cap and an expiry date.
• Buy the raw material in advance. Where plate, forgings or castings set the date, fund them early, and agree who owns and stores them.
• Order with engineering holds. Order on what is firm, such as duty, size and materials, and stop work at agreed points until you release final data such as nozzle orientations.

The risks to manage:

• Design changes after order are priced by the supplier and can cost you the slot. Freeze what drives manufacture first.
• Cancellation charges should be agreed up front, rising stage by stage as work is done.
• Storage and preservation take more than a dry shed. WEG's motor guide, for example, recommends turning the shaft by hand at least monthly and keeping any heater on while a motor waits to be installed [6]. Agree who stores, preserves and insures the item, and when ownership and risk pass.

This is general information, not legal advice.

Practical example

A chemicals site is adding a skid based unit with a gas compressor and a new 33/11 kV supply. Front end design starts today, week 0, with sanction planned for week 26 and design freeze for week 40. All figures are illustrative. Lead times are all in, including drawing approval and shipping.

The transformer and compressor must be ordered before sanction. Ordered at design freeze, the normal point, they would arrive 32 and 30 weeks late. With eight weeks allowed to enquire, evaluate and approve, the transformer enquiry must start now. Management approves a slot reservation and a capped notice to proceed for compressor engineering: a known sum at risk, against about seven months of delay.

The column is ordered at sanction, four weeks before its latest date, with an engineering hold on nozzle orientations, and the fabricator buys the duplex plate at once.

The switchgear is not long lead on this plan, but with only four weeks of float after design freeze it goes on the watch list. The pumps follow normal procurement.

Build your options before you need them

A long lead list helps most when it is early and critical items have more than one credible supplier.

ChemCapital's Supplier Discovery searches the web for suppliers whose products match your duty point, so you can line up qualified alternates for critical items early. Send a structured RFQ early: every supplier gets the same request at once, quotes arrive in a consistent format for side by side comparison, lead times included, and after the order suppliers post milestone updates.

Ready to find your long lead items while there is still time to act? Start a free 14 day ChemCapital trial, with no credit card needed.