API 600 Gate Valves — Bolted-Bonnet, OS&Y, 150# – 2500#

API 600 covers bolted-bonnet steel gate valves commonly used for in-plant isolation in refinery, petrochemical and process-piping systems. The standard defines construction, body-wall, trim, stem and test requirements across its stated size and pressure-class scope. RP Sales coordinates Kanpur enquiries by matching body material, trim, ends, test scope and approved-manufacturer requirements to the buyer's valve datasheet before seeking a commercial offer.

Plant contractors, sugar mills and process-skid builders in Kanpur, Panki, Unnao and Dada Nagar can use RP Sales as the commercial and documentation point for these valves. The quotation identifies the proposed manufacturer, applicable API licence evidence, GST treatment, inspection scope and delivery basis. Because production slots and inspection dates change by order, shutdown planners should share tag lists and the required-on-site date before accepting a schedule.

What API 600 covers

API 600 is the API Standard 600 (current edition 14th, 2021) for steel gate valves in flanged or buttweld ends. It mandates a bolted bonnet (not welded), an OS&Y stem as standard, and lays out body wall thickness for each pressure class as a function of bore size. The standard cross-references API 598 (the valve inspection and testing standard for the production hydrostatic and seat tests) and the trim selection from a numbered table. Compliance is enforced through the API monogram licensing program — only API 600-licensed manufacturers can stamp the valve with the API monogram.

The spec starts at NPS 2" — small-bore gate valves below 2" NPS fall under the related API 602 standard for forged-body gates. Above NPS 24", fabricated-body valves to ASME B16.34 or the buyer's plant spec are typically used because the cast-body weight becomes impractical. The pressure-class range is the same B16.34 / B16.5 family — 150, 300, 600, 900, 1500, 2500 — and the pressure-temperature ratings come from B16.34 by material group.

Sizes & pressure classes

Body materials we coordinate

• WCB (ASTM A216) — carbon-steel casting grade; use only where the approved valve datasheet and materials review specify it.
• LCC (ASTM A352) — low-temperature carbon-steel casting grade; verify the exact grade, impact-test temperature and acceptance criteria from the project documents.
• WC6 (1.25Cr-0.5Mo) — elevated-temperature alloy for steam, hot oil, hydrogen service to ~540 °C.
• WC9 (2.25Cr-1Mo) — higher-temperature alloy for boiler feed, reactor effluent service.
• CF8 (304) / CF8M (316) — austenitic stainless for corrosive process service.

Trim selection per the API 600 trim chart

Trim is the combination of seat ring, disc / gate face, stem, and back-seat materials. The most-ordered trims:

• Trim 1 (13Cr) — economy refinery trim for low-erosion service.
• Trim 5 (Stellite hardfaced) — abrasive / high-temperature service, longest wear life.
• Trim 8 — one defined trim arrangement; specify it only when the approved datasheet and current API 600 edition support that selection.
• Trim 12 (316/316L) — corrosive process service, matched to CF8M body.

Honest framing — how we work

RP Sales is a wholesale distributor of steel pipes, tubes, fittings and valves, not an API 600 valve manufacturer. We coordinate API 600 gate-valve supply from Indian or imported manufacturers that match the buyer's approved-vendor and origin requirements. The order should name the manufacturer, required licence evidence, test scope and inspection agency; those items are confirmed in the quotation rather than assumed for every enquiry.

Buying API 600 gate valves from Kanpur

The Kanpur route is primarily about specification control: body grade, trim, end connection, pressure class, test scope and approved manufacturer must agree before an order is placed. RP Sales asks the proposed shop for its current production window and licence evidence, then aligns any TPI hold points with the buyer's inspection plan. The resulting quotation records the order-specific schedule instead of treating a broad size or alloy category as a guaranteed lead-time band.

Delivery is quoted against the consignee PIN code, packing needs, shipment weight and the carrier service available when the goods are ready. An imported-origin request is priced only after the maker confirms availability and the logistics basis. Quote validity, GST, freight responsibility and any inspection-release condition appear on the individual offer, so buyers can compare like-for-like commercial terms without relying on a generic transit promise.

Start with the Kanpur steel market guide and the steel pipes Kanpur page, then send the datasheet or tag list through the RFQ form.

Who should use API 600 gates and who should not

API 600 gate valves are used for in-plant isolation duties when the approved valve specification selects that standard and design. Size, class, body, bonnet, trim, stem arrangement, ends, testing and fire qualification must follow the tag datasheet. A service label such as refinery, fire protection, LPG or corrosive process does not by itself select OS&Y, LCC, CF8M or a trim number.

Check a piggable transmission-line valve against the project's API 6D or other pipeline-valve requirement rather than assuming API 600. Gate valves are generally specified for isolation, but the approved operating philosophy and manufacturer data decide whether another valve type is required for control duty. For smaller sizes or a different bonnet construction, use the valve standard named on the datasheet. Where position indication is required, write the accepted stem arrangement into the tag specification.

Pressure-class selection by service

Service mapping per the body and trim lists on this page, reviewed 24 May 2026. Confirm ratings against B16.34 tables for the exact material group.

RFQ checklist for API 600 gate valves

A complete valve line reads: NPS and class (for example 4 inch 150#), ends (flanged or buttweld), body grade (WCB), trim number (Trim 8), stem (OS and Y or NRS), and quantity against tag numbers. The tag list or datasheet carries the design pressure and temperature so the class choice can be checked.

• Size, class, ends, body, trim. State NPS, 150# to 2500# class, flanged or buttweld ends, body grade and the API 600 trim number explicitly.
• Stem, bonnet, fire rating. State the approved stem and bonnet construction plus the exact fire-test standard and qualification scope where the project requires it.
• Testing and inspection. Production hydro and seat tests follow API 598; state the required material certificate and third-party inspection scope in the order so the manufacturer can include them in its inspection plan.
• Origin and delivery. State Indian API 600-licensed or imported origin, tag-wise quantities, delivery PIN code and ex-works Kanpur or delivered basis.

Worked example: valve count for a 20-point utility header

Take an approved utility-header tag list with 20 isolation points: 12 on 4 inch lines and 8 on 6 inch lines. Base count is 12 plus 8, which is 20 valves. Copy class, ends, body, trim and stem arrangement from each tag rather than assigning WCB, Trim 8 or OS&Y as planning defaults. Count matching gasket and bolting sets from the actual joint arrangement.

Add 10 percent spares for shutdown cover, rounding each size up: 12 × 1.1 is 13.2, which rounds up to 14 of the 4 inch valves, and 8 × 1.1 is 8.8, which rounds up to 9 of the 6 inch valves. The final order is 23 valves plus 20 gasket and bolting sets for the 20 installed joints. Send this shape of tag list with design conditions and the class gets verified before booking.

Common mistakes and inspection points

In practice, valve orders fail on five points. First, trim materials are missing from the PO and the shop interprets an incomplete datasheet. Second, API 600 is specified where the project requires a different valve standard. Third, stem position indication does not match the approved fire or operating philosophy. Fourth, production and inspection timing is checked only after the shutdown date is fixed. Fifth, the required manufacturer approval or licence scope is never verified for the offered model and site.

At receipt, match body markings and heat numbers to the MTC, verify the trim stamp against the PO, witness or review the API 598 hydro and seat test records, and confirm flange drilling matches the mating B16.5 flanges before the valves leave for site. For WC6 and WC9 bodies, check post-weld heat treatment records in the dossier.

Standards and compliance

API 600 (14th edition, 2021) governs the bolted-bonnet gate valve envelope, body wall thickness, trim chart and OS and Y stem. Production inspection and testing follow API 598, and fire qualification follows API 607, API 6FA or ISO 10497 where specified. Pressure-temperature ratings come from ASME B16.34 by material group, with flange drilling per ASME B16.5. Body grades follow ASTM A216 (WCB, WCC), ASTM A352 (LCC), WC6 / WC9 / C5 alloy and CF8 / CF8M stainless practice.

Sour-service trims follow NACE MR0175 / ISO 15156 hardness practice. Where the valve is legally treated as a boiler mounting or fitting, the applicable IBR certificate is Form III-C; that form should not be assigned merely because a valve sits near a steam line. IBR steam pipes use Form III-A and boiler tubes use Form III-B. Matching pipe grades sit on ASTM A106 and ASTM A335.

Key points

• API 600 covers 2 inch to 24 inch bolted-bonnet gates in classes 150 to 2500.
• No trim is a refinery default; copy the approved gate, seat, stem and hardfacing materials from the valve datasheet.
• Gates are for isolation only; throttling and pigging need different valve types.
• Production and delivery timing must be confirmed against the selected manufacturer, inspection scope and destination.
• Ask for the monogram licence number and the API 598 test records on every order.

Sources and references

• API 600, Bolted Bonnet Steel Gate Valves, 14th edition (2021): scope, walls, trim chart, OS and Y stem (cited by code, edition and clause; no catalogue URL).
• API 598, Valve Inspection and Testing: production hydro and seat tests (cited by code; no catalogue URL).
• API 607 / API 6FA / ISO 10497, Fire-type testing of valves (cited by code; no catalogue URL).
• ASME B16.34 / B16.5, pressure-temperature ratings and flange drilling: see the ASME B16.5 reference.
• Sour-service and boiler documentation: see NACE MR0175 and IBR.

Related catalogue and reference pages: weld neck flanges 150#, forged fittings B16.11, seamless pipes, ASTM A106, ASTM A335, MTC & TPI, Kanpur steel market, steel pipes Kanpur, steel pipes Lucknow, request a quote.

FAQ — API 600 gate valve selection