In some projects, particularly those that are fast-tracked, the equipment procurement process are likewise expedited. Long-lead equipment procurement are normally initiated during the early phase of the project where there are still so many unkown parameters. This scenario is the most likeable to equipment vendors. Why?
As there are still to many unknowns, some details of designs were actually relied upon the vendors standard practices. Specifications are very generic. Datasheets got so many blanks or vendor to advise (VTA) items.
Vendors will offer whatever is required by the procurement documents but the offer will contain lots of exclusions leading a very basic and unusable equipment. If the engineer is not keen enough to spot these exlcusions and buy the equipment from the vendor, at the end of the day, the equipment cost will skyrocket much more than its cost if it will be bought without change orders.
If the engineer decides to make do of what if offered by the vendor, then the equipment may not be suitable for the desired application.
This dirty tactic is very common for vendors, the engineer is therefore advised that despite the urgency of their project, thorough technical evaluation of bids is necessary. If in doubt, ask! Send out a technical query to the vendor concern.