In refinery and petrochemical projects the material selection follows the piping class list. Each class defines pipe material, wall thickness, flange class, gasket type, fastener and valve body together. We quote item by item against that list, and where we propose an equivalent outside the specification, we say so explicitly.
A line in a piping class defines a whole set, not a single item:
Where the class changes, the item changes too. Catching those transitions correctly in the quotation prevents incompatible material appearing on site.
Fluids containing H2S carry a risk of sulphide stress cracking. NACE MR0175 / ISO 15156 defines hardness limits and production conditions for these services. In practice we watch:
In process units the documents are part of the delivery. Depending on the scope we provide EN 10204 3.1 or 3.2 inspection certificates, heat number traceability, PMI reports, dimensional and visual inspection records and, where required, non destructive testing records.
Because the certificate level directly affects lead time, we recommend stating the required certificate with the enquiry.
Can you quote without a piping class list?
Yes, provided material grade, pressure class and service conditions are stated. Without them, a price carries the risk of incompatible material on site.
Do you supply NACE MR0175 compliant material?
Yes. Flanges, fittings and fasteners for sour service are supplied with NACE MR0175 / ISO 15156 compliance reported on the certificate.
Does a 3.2 certificate extend lead time?
Usually yes. A 3.2 document requires approval by an independent inspection body or the customer representative, which adds time to production and shipment.
Share your item list, isometrics or MTO file for your petrochemical requirement; we reply with price and lead time the same day.