Valve datasheets in tenders: what EPC buyers check line by line

What does a valve datasheet ask for, line by line?

Our general guide to technical datasheets in tenders covers the legend, who fills which column and the meets-or-exceeds rule. This post stays with the valve lines themselves, because that is where most valve offers pick up their technical queries.

An EPC valve datasheet usually runs to 30 or 40 rows per tag. They fall into six groups, and the evaluator on the buyer's side checks each group against a different document.

Read the rows in that order. A wrong material is expensive to fix after the order, but a certificate that does not cover the tag can knock out the whole technical offer.

Pressure class, design conditions and end connections

Class 600 does not mean 600 psi. Under ASME B16.34, the allowable pressure for a class depends on the material group and falls as temperature rises. So a carbon steel body and a chrome-moly body in the same class carry different pressures at 400 degrees C. The evaluator reads your offered body material, looks up its rating at the design temperature on the datasheet and checks it still covers the design pressure.

This is where substitutions bite. Offer a forged body in place of a casting, or a stainless grade in place of carbon steel, and the rating table changes even though the class does not. Show the rating check for any tag where you changed the material.

• Flanged ends: confirm the facing per tag. RF, FF and RTJ are not interchangeable, and the piping class decides, not your standard build.
• Butt-weld ends: the bevel and the bore must match the pipe schedule. If the datasheet gives no schedule, ask for it before you quote.
• Socket-weld and threaded ends: check the size limit in the specification. Many piping classes allow them only at 1.5 or 2 inch and below.
• Face-to-face: state the dimension standard and pattern (short or long). A pipeline ball valve and a process ball valve of the same size can differ here.

Body, trim and bolting materials: where valve offers slip

Evaluators want a grade per part. "Body: carbon steel, trim: SS" will draw a query on every tag. Write the full specification and grade, such as ASTM A216 WCB or A105 for the body, and the actual stem, seat and closure member materials.

Gate, globe and check valves to API 600 or API 602 often specify a trim number rather than single materials. A trim number bundles the stem, seat surfaces and wedge or disc materials into one set. If you offer a different trim number, that is a change to three parts at once, and it goes on the deviation sheet as one item with all three listed.

• Low temperature service: carbon steel castings and forgings change grade (for example LCB or LCC castings, A350 LF2 forgings) and need impact tests at the stated temperature. Check the minimum design temperature row on every tag.
• Bolting: the bolting row is often far from the body row. Sour service and low temperature both change bolting grades.
• Seats and seals: a soft seat material has a temperature limit. If the design temperature is above it, the soft seat is a deviation even if the body is fine.
• Coatings and overlays: an ENP coating, hardfacing or weld overlay is a material commitment. Name the process and thickness if the datasheet asks.

NACE and sour service on a valve datasheet: what you commit to

A row that says "NACE MR0175" or "sour service" means materials in contact with the process fluid must meet the hardness and heat treatment limits of NACE MR0175 / ISO 15156 (oil and gas production) or NACE MR0103 (refining), depending on which the buyer names. The evaluator expects the material certificates to state compliance and, for many grades, hardness values.

The trouble is scope. The datasheet rarely says which parts the requirement covers: wetted parts only, all pressure-containing parts, or bolting too. Bolting matters because it may be buried under insulation or in a closed space, and some specifications then treat it as exposed.

Fire-safe and fugitive emission rows: does your certificate cover the tag?

Fire-safe and emission requirements are proven by type tests, not by production tests. You test one valve of a design, and the certificate then qualifies a range of sizes and classes. That range is what the evaluator checks against each tag.

API 607 is the usual fire test for quarter-turn valves and valves with nonmetallic seats; specifications for pipeline valves often cite API 6FA, and European ones ISO 10497. A practitioner guide puts the risk plainly: a fire test on a 6 inch Class 150 ball valve does not automatically qualify a 12 inch Class 600 valve of the same design (Project Materials (opens in a new tab)).

Fugitive emission is similar. ISO 15848-1 is a type test that gives a valve design a performance class built from three parts: a tightness class (AH, BH or CH with helium), an endurance class and a temperature class. For on-off valves, endurance class CO1 means 205 full mechanical cycles and two thermal cycles (Valve World Americas (opens in a new tab)). ISO 15848-2 is the production test done on supplied valves, and it does not replace the type test.

• Match the certificate's valve type, bore and seat design to the tag.
• Check its size and class range covers the tag's size and class.
• For emission, check the tightness class, endurance class and temperature class each meet or beat the datasheet row.
• Name the certificate number and test laboratory on the datasheet, and enclose the certificate.

Valve leakage class and pressure tests: API 598, ISO 5208 and "as per standard"

The test rows are short, and that is the problem. "Hydrotest: as per standard" leaves the test standard, the leakage rate and the low-pressure gas test to interpretation.

API 598 and ISO 5208 both test the shell at 1.5 times the rated pressure and the seat at 1.1 times, with a low-pressure air or gas seat test. Rate A means no visible leakage in both. For metal-seated valves, though, the allowed leakage differs between the two standards, and ISO 5208 adds looser rates E to G (Project Materials (opens in a new tab)).

• State the test standard and rate per tag, for example "Seat test to API 598" or "ISO 5208 Rate B".
• If the datasheet asks Rate A on a metal-seated valve, check whether your design meets it. If not, query it or list it as a deviation.
• For double block and bleed or double isolation and bleed ball valves, confirm the cavity test and cavity relief arrangement asked for.
• Note which tests are witnessed by the buyer or a third-party inspector, because that sets your test schedule and cost.

Illustrative example: twelve valve tags for a refinery revamp near Vadodara

A forged and cast valve maker in Rajkot receives an EPC enquiry for twelve tags on a hydrotreater revamp: forged gate and globe valves at 2 inch and below, cast gate valves from 4 to 10 inch, and two metal-seated ball valves. The engineer runs each tag through the six line groups before anyone prices it. The tags and values below are invented for the example.

Twelve tags produced two pre-bid queries and two deviations. Without the line-by-line check, at least one of those would have surfaced as a technical query after bid opening, when there is far less room to fix it.

AI on valve datasheets: what it reads and what your engineer signs

Most of the reading above is finding the same kinds of rows across dozens of tags. TenderGenie's Keywords Extraction pulls out product types and standards such as API 607, ISO 15848-1 and NACE from the tender, so you see early which tags carry which requirements. Its Enquiry Checklist sorts requirements into what you supply, what you already meet and what is missing, like a fire test you do not hold for a size.

In TenderGenie, Datasheet Extraction and Filled-in Datasheet then take values from your catalogs and fill the buyer's datasheet format for review. See the valve manufacturers page for a worked enquiry.

What stays with your engineer: the rating check after a material change, whether a certificate range really covers a tag, how to answer an open NACE scope, and every deviation. Those are judgments with your name on them, and software should show its sources so you can check them. Once the deviations are decided, our guide to the technical deviation sheet covers how evaluators read them.

Questions and answers