API 6A Annex F "718" Trim Forgings — Age-Hardened Nickel Alloy Stems, Gates & Seats for Sour, High-Pressure/High-Temperature Wellhead Service
Shivam Forge manufactures forged stem, gate, seat, and other internal trim components in age-hardened nickel alloy (Alloy 718 type, UNS N07718) meeting the API 6A Annex F "718" trim material designation — the NACE MR0175-compliant, high-strength trim specification called for on the most demanding sour and HPHT wellhead and Christmas tree components. Rajkot, India. Call +91-9265772827.
API 6A's Annex F material designation system defines approved combinations of pressure-containing body material and internal trim material for wellhead and Christmas tree equipment, recognizing that the body (the pressure boundary itself) and the trim (the internal functional parts — stems, gates, seats, and other components subject to direct flow contact, sliding wear, and sealing duty) face genuinely different service demands and can reasonably be specified in different materials within the same component. The "718" trim designation within this framework calls out age-hardened nickel alloy, typically Alloy 718 type chemistry (UNS N07718), specifically for the trim components of the most demanding wellhead applications — high-pressure, high-temperature (HPHT) sour gas wells in particular — where standard 17-4PH or other precipitation-hardening stainless trim doesn't deliver an adequate combination of strength, galling resistance, and NACE MR0175-compliant sulfide stress cracking resistance simultaneously. This page sits specifically underneath the site's broader API 6A wellhead equipment coverage and its NACE MR0175 sour service material coverage: API 6A defines the overall wellhead component specification framework (PSL testing tiers, PR design validation levels), NACE MR0175 defines the sulfide stress cracking resistance requirements sour service imposes across material selection generally, and the "718" trim callout is the specific material answer API 6A Annex F provides when a component's trim needs to satisfy both frameworks simultaneously at the top of the pressure, temperature, and sourness range those specifications cover. Getting a 718 trim component right means controlling both the nickel alloy's inherent high-temperature strength and galling resistance and its hardness within the sour-service limit NACE MR0175 defines — two requirements that pull in the same general direction for this alloy but still both demand explicit process verification.
Forged valve stem blanks in Alloy 718 type nickel alloy for Christmas tree and wellhead valve applications requiring the strength and galling resistance this trim material delivers under repeated actuation in sour HPHT service.
Forged gate and seat component blanks in 718 trim material, engineered for the sliding and sealing contact wear these components experience while maintaining NACE MR0175-compliant hardness for sour service qualification.
Forged internal trim components for choke and flow control equipment handling high-velocity, potentially erosive sour production fluid, where 718 trim's strength and corrosion resistance combination is specified for demanding HPHT wells.
Forged body components in the appropriate API 6A-approved base material paired with 718 trim internals, supplied together or separately to match your Annex F material designation requirement for the complete wellhead assembly.
Solution treatment and controlled precipitation age-hardening heat treatment developing the specific high-temperature strength and galling resistance the 718 trim designation requires for wellhead internal components.
Documented hardness testing confirming 718 trim components meet NACE MR0175 / ISO 15156's sulfide stress cracking hardness limit alongside the alloy's mechanical strength requirement, since both properties must be satisfied together for sour service qualification.
Material and documentation support confirming the specific body-and-trim material combination your wellhead component order specifies aligns correctly with API 6A Annex F's approved designation table.
Complete chemical composition and mechanical property certification per EN 10204 3.1, with 3.2 third-party witnessed certification available for wellhead equipment manufacturer and operator project documentation requirements.
Wellhead and Christmas tree equipment specification recognizes something that a single uniform material callout would miss: the pressure-containing body of a valve or wellhead component and its internal trim — the parts that actually contact flowing production fluid, slide against each other during actuation, and seal against pressure — face genuinely different service demands, and a material well suited to one role isn't necessarily the right choice for the other. API 6A's Annex F designation system formalizes this distinction by defining approved body-and-trim material combinations rather than a single grade per component, and the "718" trim designation sits at the demanding end of that table, called out specifically when a component's internal trim needs to survive the combined stresses of high pressure, high temperature, and sour (H2S-containing) production fluid simultaneously.
Alloy 718 type nickel alloy earns this position because it delivers a combination of properties that standard precipitation-hardening stainless trim grades, adequate across a broad middle range of wellhead applications, don't consistently match at the top of the demand curve: meaningfully higher strength retention at elevated temperature, strong resistance to galling under the repeated sliding and actuation contact valve trim experiences over thousands of open-close cycles, and — with appropriate hardness control — compliance with NACE MR0175's sulfide stress cracking resistance requirements for sour service. This combination is exactly what high-pressure, high-temperature sour gas wells demand from their wellhead and Christmas tree internals, applications where a trim failure isn't a minor maintenance event but a direct threat to well control.
Manufacturing 718 trim components correctly requires holding both halves of this requirement simultaneously rather than optimizing for one at the expense of the other: the age-hardening heat treatment sequence needs to develop the alloy's full strength and galling resistance, while hardness across the finished component needs to stay within NACE MR0175's specified limit for the applicable material category, since even a nickel alloy specifically selected for sour service can become more susceptible to sulfide stress cracking if processed to excessive hardness. This is a documented, testable requirement, not a matter of alloy selection alone — which is why hardness verification, not just material certification, is central to genuine 718 trim quality assurance.
For wellhead equipment manufacturers and oil and gas operators sourcing forged 718 trim components for HPHT sour service Christmas tree and wellhead equipment, Shivam Forge manufactures stems, gates, seats, and related trim internals with controlled age-hardening heat treatment and documented NACE MR0175 hardness verification. Contact our engineering team at +91-9265772827 or sales@shivamforge.com with your API 6A Annex F material designation and service conditions for a manufacturability review and quotation.
It specifies the internal trim components — stems, gates, seats, and similar functional parts subject to flow contact and sealing duty — be manufactured in age-hardened nickel alloy, typically Alloy 718 type chemistry (UNS N07718), rather than standard precipitation-hardening stainless trim. It applies to the trim specifically, not necessarily the pressure-containing body, which is why API 6A Annex F treats body and trim material as a combination rather than a single material callout.
The API 6A wellhead page covers the overall specification framework governing wellhead and Christmas tree equipment — PSL testing tiers and PR design validation levels. The NACE MR0175 page covers sour service material requirements generally, across many component types. This page covers the specific 718 trim material sub-requirement API 6A Annex F calls out when a wellhead component's trim needs to satisfy both frameworks together at the demanding end of the pressure, temperature, and sourness range those specifications address.
17-4PH and similar precipitation-hardening stainless trim grades perform well across a broad range of wellhead service conditions, but at the combined extremes of high pressure, high temperature, and sour (H2S) service, they can fall short on the specific combination of high-temperature strength, galling resistance under repeated actuation, and sulfide stress cracking resistance the application demands simultaneously — which is why API 6A Annex F specifies the higher-performing 718 trim material for these more demanding designations.
Yes. Even though Alloy 718 type nickel alloy is inherently well suited to sour service, hardness still needs to be controlled and documented within NACE MR0175 / ISO 15156's specified limit for the material category, since hardness — not alloy family alone — is the direct driver of sulfide stress cracking susceptibility.
Yes. We can forge the pressure-containing body in the appropriate API 6A-approved base material alongside the 718 trim internal components, supplied together or separately depending on how your wellhead equipment manufacturer's assembly and qualification process is structured.
Why Choose Shivam Forge
Shivam Forge delivers precision hot-forged components from our integrated Shapar, Rajkot facility — covering forging, CNC machining, heat treatment, and quality inspection under one roof.
