Technical Guides
7 min read

API 6D vs API 600 vs API 602 Gate Valve — Key Differences Explained

API 6D, API 600, and API 602 all cover steel gate valves but for very different applications — pipeline, process plant, and compact forged respectively. This guide explains which to specify.

API 6DAPI 600API 602Gate ValvesStandards

In This Article

  1. 1.API 6D — Pipeline Ball, Gate, and Check Valves
  2. 2.API 600 — Process Gate, Globe, and Check Valves
  3. 3.API 602 — Compact Forged Steel Gate Valves
  4. 4.Comparison Table

Three API standards cover steel gate valves: API 6D (pipeline valves), API 600 (steel gate, globe, and check valves for general process service), and API 602 (compact design forged steel gate valves for small-bore instrument service). While all three produce gate valves, the design intent, testing requirements, and application environments are fundamentally different.

API 6D — Pipeline Ball, Gate, and Check Valves

API 6D covers valves used in liquid and gas pipeline service. Key features: full-bore (piggable) design mandatory; bi-directional seating; fire-safe design per API 6FA; anti-static device; sealant injection fitting for emergency seat sealing; bleed/vent provisions. API 6D includes both ball valves (primary scope) and through-conduit slab gate valves for crude oil and gas pipeline service. It is NOT intended for refinery process service — API 600 applies there.

API 600 — Process Gate, Globe, and Check Valves

API 600 covers flanged and butt-welding end steel gate valves DN50 (2") and larger for general process service in oil refineries, petrochemical plants, and process industries. Key features: bolted or pressure-seal bonnet (pressure-seal for Class 900+); OS&Y (outside screw and yoke) stem; solid wedge, flexible wedge, or split wedge gate; Class 150 through 2500. API 600 does NOT require fire-safe or full-bore designs — these are selected by the user if needed.

API 602 — Compact Forged Steel Gate Valves

API 602 covers small-bore (DN8 to DN50, ½" to 2") compact forged steel gate valves for instrument and process service. Key features: integrally forged bonnet (not bolted); socket weld (SW), butt weld (BW), or screwed (NPT) end connections; Class 800/1500/2500. API 602 valves are the standard for instrument root valves, gauge isolation, and small-bore process taps.

Comparison Table

FeatureAPI 6DAPI 600API 602
ApplicationPipeline isolationProcess plant general serviceSmall-bore instrument/process
Size rangeDN50–DN1200DN50 and largerDN8–DN50 (½"–2")
BoreFull-bore (piggable) requiredReduced or full-bore, user specifiesReduced bore standard
Bi-directionalRequiredNot requiredNot required
Fire-safeRequired (API 6FA)Optional (user spec)Optional
End connectionsFlanged, BWFlanged, BWSW, BW, NPT, flanged
Body constructionCast or forgedCast (bolted/PS bonnet)Integrally forged
Pressure classes150–2500150–2500800/1500/2500
Testing standardAPI 6D Section 9API 598API 598

Request Gate Valve Quote

API 6D certified. Ships worldwide. 24-hour quote response.

Request Quote →
Published: Last updated:

Need industrial valves for your project?

API 6D, ASME B16.34 certified. 120+ cities served. 24-hour quote response.

Vajra Industrial Solutions — Where We Supply

We supply certified industrial valves to 120+ cities worldwide