This article on Inspection Scope will provide you information about the scope of work for third party inspection, shop inspection and pre-shipment inspection.
A more stringent scope of work will cause higher inspection costs and higher assurance for quality products and a less stringent scope of work will cause less cost and higher risk of producing non-conforming products.
So you need to optimize your inspection level. You may consider 6 man days for your centrifugal pump construction or 1 day; it is up to you. The scope of inspection is determined by the purchaser through inspection and test plan.
For more information on this, please review the Inspection and Test Plan article. To completely comprehend this article, download one of the equipment inspection and test plans and review it alongside the rest of this article.
The inspection and test plan is in a tabulated format and in the responsibility section there are three columns: one for manufacturer, one for the third party inspector and one for the client.
So you as a client or purchaser can modify the Third party inspection (TPI) column by changing the hold and witness points to review points and decreasing your inspection level or create a less stringent inspection scope which decreases your inspection cost, and at the same time increases the risk for production of non-conforming products.
Conversely, you may change the review points to witness and hold points and increase your inspection level or create a more stringent inspection scope, which increases your inspection cost, and at the same time decreases the risk for production of a non-conforming product.
When you determine the inspection level, you must take this point in to account: inspection never decreases or eliminates the manufacturer's responsibility.
So even though, you may designate a resident inspector to a manufacturer's factory to supervise entire quality control activities, but if you receive your equipment on your premises, and you see non-conformity, the manufacturer is still responsible.
You may ask why we hire an inspection agency when the manufacturer is responsible for delivering a quality product.
For two reasons: the first reason because we are taking preventive measures and making sure that goods received on our premises are the same specification as stated in the Proforma Invoice(PI) and in the Purchase Order(PO) and to avoid any probable dispute between the purchaser and manufacturer.
The second reason is because of the LC (Letter of Credit) requirement. For equipment for which an LC is opened at the buyer's bank, an inspection certificate issued by third party inspection agency might be required to be delivered to the seller's bank for payment.
In this case, inspection is done because of bank requirement. Please note: in some countries this is a mandatory rule for designating an inspection agency for equipment with an LC transaction and in some others it is optional and normally agreed on between the buyer and the seller.
We have placed many inspection and test plans for different equipment in this website, and we placed a logical inspection level or scope for an inspection agency. So you may use these inspection and test plans as a draft for your project.