1.7375 (12CrMo9-10) Forged Forging Parts | China Professional Open Die Forging Manufacturer

1.7375 (12CrMo9-10) Alloy Steel Forging Overview

Jiangsu Liangyi Co.,Limited is a professional ISO 9001:2015 certified open die forging manufacturer based in Jiangyin City, Jiangsu Province, China. Since our founding in 1997, we have focused exclusively on heavy alloy steel forgings for the global pressure equipment market. Today, our 80,000㎡ manufacturing campus houses the full vertical supply chain — from in-house electric arc furnace smelting and vacuum degassing, through heavy hydraulic press forging, controlled atmosphere heat treatment, precision CNC machining, and full-set non-destructive testing — all under one roof. Our annual forging capacity reaches 120,000 metric tons, and we have built a verified export track record serving customers in more than 50 countries across Europe, North America, the Middle East, East Asia, and Australia.

Among our main alloy grades, 1.7375 (12CrMo9-10) — also designated 12CrMo910 or 12CrMo9.10 — represents one of the most technically demanding materials in the European pressure equipment steel family. Governed by EN 10028-2:2009, this chromium-molybdenum alloy steel is engineered specifically for parts that must retain structural integrity under sustained high temperature and pressure, where conventional carbon steels would suffer accelerating creep deformation and premature failure. The 2.00–2.50% chromium content builds a stable oxide film that resists steam and flue-gas corrosion, while the 0.90–1.10% molybdenum disperses as fine carbide precipitates within the ferrite matrix, dramatically retarding the dislocation movement that causes creep. The combination gives 12CrMo9-10 a certified maximum operating temperature approximately 75–100°C higher than the lower-alloyed 1.7335 (13CrMo4-5) grade, so that it is the best choice material for super important boilers, high-pressure heat exchangers, nuclear reactor coolant systems, and API 6A pressure boundary parts where wall temperatures exceed 480°C.

All our 1.7375 forged parts are produced with flexible custom MOQ starting from 1 piece, standard 15–30 day lead time, and full EN 10204 3.1 material test certification — with EN 10204 3.2 third-party inspection available on request. Contact our technical team to discuss your specific pressure, temperature, dimensional, and standard requirements.

1.7375 (12CrMo9-10) Forged Steel Product Forms & Custom Capabilities

Jiangsu Liangyi provides a full range of service for 1.7375 (12CrMo9-10) forged steel products, from initial billet melting and forging stock preparation through open die press forging, seamless ring rolling, controlled atmosphere normalizing and tempering heat treatment, CNC machining, surface treatment to full-set NDT. And all parts are delivered with EN 10204 3.1 or 3.2 test certification. Below are the specific product forms we manufacture and their principal engineering parameters:

Forged Bars & Billets

We produce 1.7375 forged round bars in diameters from 50mm to 1,500mm, square bars from 50mm to 800mm, flat bars in thicknesses from 30mm to 600mm, and rectangular billets for downstream machining. All bars are forged with minimum 3:1 forging ratio to break down the cast structure and guarantee fine, equiaxed grain throughout the cross-section. Typical delivery condition: normalized and tempered (+NT) to Brinell hardness 160–220 HB. We can supply rough-turned stock, saw-cut billets, or precision-machined rods per your CAD drawing.

Seamless Rolled Rings & Flanges

Using our CNC radial-axial ring rolling mills, we produce 12CrMo9-10 seamless rolled rings with outside diameter from 200mm to 6,500mm, heights from 50mm to 1,800mm, and wall thicknesses from 30mm upwards. Ring products include forged weld neck flanges, slip-on flanges, blind flanges, orifice flanges, spectacle blinds, swivel ring flanges, retaining rings, and custom profiled rings. Dimensional accuracy typically achieves OD tolerance within ±2mm and height within ±1mm before machining. We manufacture parts based on ASME B16.5, ASME B16.47, EN 1092-1, DIN 2631–2638, and custom drawings.

Hollow Forgings: Shells, Sleeves, Hubs & Casings

We use professional mandrel adjusting tools and high-tonnage hydraulic presses to forge our 1.7375 hollow parts. This method makes sure that the wall thickness is always the same. This is great for pump casings, valve bodies, turbine housings, and gear ring blanks. We also make hollow bars and thick-wall pipes by hollow forging them and then boring them to the right size. For finished forged parts, we keep ovality within ≤0.3% of the outer diameter.

Forged Discs, Disks & Flat Blocks

We forge 12CrMo9-10 discs and blocks in diameters up to 4,500mm and thicknesses up to 1,200mm, with weights from 30kg to 30,000kg per piece. These products serve as turbine disc blanks, tube sheet stock for heat exchangers and condensers, pressure vessel heads, flange blanks, and structural blocks for pressure boundary assemblies. Forging is performed with minimum 3:1 upset ratio and 90° cross-forging to achieve isotropic mechanical properties in both longitudinal and transverse directions.

Pressure Piping Parts: Pipes, Nozzles & Tube Sheets

Our 1.7375 forged seamless pipes and nozzles are produced by hollow forging and mandrel elongation, achieving outside diameters from 76mm to 600mm and wall thicknesses well beyond the capability of rolled and welded construction. Tube sheets for shell-and-tube heat exchangers are forged in diameters up to 3,800mm and face-machined to flatness within 0.1mm per meter. Forged nozzles, channel flanges, and reducer fittings are machined complete from forged blanks per ASME VIII, EN 13445, or project-specific engineering drawings.

Precision-Machined Parts: Shafts, Valve Bodies, Impellers & BOP Components

For customers needing finished or semi-finished machined parts, we provide complete CNC machining services on our 5-axis machining centers and CNC lathes with 6-meter swing capacity. Product examples include: large pump shafts (diameter 100–600mm, length up to 8,000mm); centrifugal pump impellers (diameter 200–1,800mm); gate valve and globe valve bodies (pressure class ANSI 150–2500); blowout preventer bodies and bonnets; transition cones; wye pieces and swept branches. Machining accuracy: bore tolerance H7, shaft tolerance h6, surface finish Ra 0.8–3.2μm as standard.

Industry Applications & Verified Field Cases of 1.7375 (12CrMo9-10) Forgings

The selection of 1.7375 (12CrMo9-10) for a given pressure equipment application is driven by three fundamental engineering requirements that no lower-alloyed steel can satisfactorily meet simultaneously: long-term creep rupture strength at temperatures above 480°C, resistance to steam oxidation and hydrogen attack in high-temperature process environments, and adequate low-temperature impact toughness for safe cold-condition pressure testing and start-up cycling. In more than 25 years of producing 12CrMo9-10 forgings, our engineering team has developed deep application-specific expertise across the following industries:

Supercritical & Ultra-Supercritical Boilers, Heat Exchangers & Pressure Vessels

In modern supercritical (SC) power boilers operating at steam temperatures of 540–570°C and pressures of 24–30 MPa, and ultra-supercritical (USC) boilers pushing to 600°C and 30+ MPa, 12CrMo9-10 is the standard material for intermediate-temperature pressure-boundary forgings where the wall temperature falls between approximately 480°C and 560°C. Typical forged components include: superheater and reheater header end caps, steam drum shell rings and nozzles, thick-wall transition pieces between ferritic and austenitic stainless piping, tube-to-header attachment forgings, and boiler drum manhole nozzles. Our 1.7375 forgings are also widely used in HRSG (heat recovery steam generator) systems in combined-cycle gas turbine plants, where thermal cycling resistance is critical. For shell-and-tube heat exchangers in petrochemical applications — hydrogen reformers, hydrogen desulfurizers, crude pre-heaters — our 1.7375 tube sheets and channel flanges are routinely supplied to ASME VIII Div.1 and EN 13445 requirements, with tube hole drilling and bore tolerances held to H8 as standard. Pressure vessel shells and hemispherical or ellipsoidal head blanks for high-temperature service reactors complete our range of boiler and pressure vessel forgings.

Industrial High-Pressure Valves & Centrifugal Pumps

The valve and pump industries demand 1.7375 forgings that combine dimensional precision with consistent mechanical properties across the entire cross-section — because a valve body with a soft core or a pump shaft with variable hardness will produce erratic seating performance or premature fatigue failure in service. Our 12CrMo9-10 valve forgings are produced to final near-net shape with machining allowances of 3–8mm per face, dramatically reducing downstream machining cycle time compared to oversized rough forgings. Core valve forging products include: globe valve bodies (ASME class 600–2500, DN25–DN600), gate valve bonnets and stuffing box flanges, ball valve ball forgings (bore diameter 15–600mm), check valve discs and seats, and pressure relief valve bodies. For pump applications, our 1.7375 pump shaft forgings get straightness within 0.05mm per meter and are supplied for final turned and ground condition. Pump casing halves, diffuser rings, and impeller blanks are CNC-machined complete from hollow forgings. All forged valve and pump parts get dimensional accuracy to ±0.02mm after machining, with consistent Brinell hardness uniformity of ±10HB across the cross-section.

Nuclear Power: High-Purity Forgings for Reactor System Components

Our premium melting capability — particularly the VIM+PESR route — positions us to supply 12CrMo9-10 forgings for nuclear power projects where the highest cleanliness and traceability requirements are specified by the customer and their applicable nuclear quality assurance framework. The technical differentiators for nuclear-application 12CrMo9-10 forgings include: selection of the VIM+PESR melting route to minimize macro-segregation and achieve low inclusion content; tighter chemistry control on S, P, and tramp residual elements (As, Sn, Sb, Pb) below customer-specified limits; full-volume UT and surface MT at elevated acceptance levels per EN 10228-3 and EN 10228-1; and comprehensive heat number traceability through every manufacturing step. The specific qualification scope — including applicable nuclear regulatory standards, third-party inspection body, and documentation requirements — is defined and agreed with each customer on a project-by-project basis prior to order placement. We do not unilaterally claim any specific nuclear regulatory certification; qualification is established through customer-led acceptance processes.

Onshore & Offshore Oil & Gas: API 6A Pressure Boundary Components

In oil and gas wellhead and Christmas tree equipment built to API 6A (ANSI/API Spec 6A, 21st Edition), 12CrMo9-10 forgings for working pressures of 5,000–20,000 psi must simultaneously satisfy tensile, impact, and hardness requirements while passing sour service qualification per NACE MR0175/ISO 15156. The main metallurgical challenge in sour service 1.7375 forgings is controlling hardness to a maximum of 22 HRC (237 HB) per NACE MR0175, which needs careful tempering temperature optimization (typically 695–720°C for this alloy) combined with slow controlled cooling to prevent re-hardening. Our API 6A product range includes: tubing head spools, casing head forgings, gate valve bodies (WP with ratings to 20,000 psi), choke body forgings, BOP (blowout preventer) body and bonnet forgings, ram block forgings, and flowline block valve bodies. For subsea Christmas tree applications, we also manufacture large-diameter (OD up to 1,500mm) profiled ring forgings to subsea equipment manufacturer drawings. All sour-service 12CrMo9-10 API 6A forgings are supplied with NACE MR0175 compliance documentation and maximum hardness certification.

Petrochemical & Hydrogen Processing Equipment

High-temperature hydrogen service (HTHA — high-temperature hydrogen attack) is an important degradation mechanism in refinery and hydrogen plant equipment above 230°C. API RP 941 (Nelson curves) defines the allowable temperature-pressure envelope for different steel grades, and 12CrMo9-10 with its 2.25Cr-1Mo nominal composition sits on the 2.25Cr-1Mo Nelson curve, which permits significantly higher service temperatures than carbon steel or 1Cr-0.5Mo grades at any given hydrogen partial pressure. Our 1.7375 forgings for petrochemical hydrogen service include: hydrotreater reactor inlet/outlet nozzles and manways, catalytic reformer charge heater fittings, hydrogen compressor valve blocks, high-pressure separator head forgings, and thick-wall piping fittings (wyes, tees, elbows) for hydrogen-rich streams. We have supplied 12CrMo9-10 reactor nozzle forgings to Saudi Arabia, UAE, South Korea, and Germany for grassroots refinery projects, with all forgings passing PWHT simulation tests and step-cooling embrittlement assessment per ASTM A387 recommendations. View our full project reference list on our Reference page.

Our Certification, Standard Compliance & Material Documentation

Jiangsu Liangyi's quality qualifications fall into three clear groups: the in-house quality management certification our company owns, the production standards followed to make our forgings, and the material report types we can provide. We clearly separate these three groups on purpose, since many suppliers mix them up, which may make buyers mistakenly believe a forging factory has certifications that actually belong to equipment assembly part makers or end customers. The following content clearly states all qualifications we own and all services we can provide.

Our 1.7375 (12CrMo9-10) Custom Forging Process: From Drawing to Delivery

Jiangsu Liangyi's one-stop custom 12CrMo9-10 forging process is designed to minimize lead time while keeping absolute quality control at every step. Unlike forging jobbers who subcontract melting, heat treatment, or machining to third parties, we own and operate every stage of the manufacturing chain in-house — giving us direct control over quality and schedule. Following are the detailed steps from the moment we receive your inquiry to the moment your forging is ready for shipment:

Production Standards & Melting Processes for 12CrMo9-10 Steel

Governing Production Standard: EN 10028-2:2009

 Our 1.7375 (12CrMo9-10) forgings are made according to EN 10028-2:2009. This European standard applies to flat steel parts for pressure use, including plain steel and alloy steel with set high-temperature performance values. In actual production, EN 10028-2 sets clear limits for chemical makeup and room-temperature mechanical performance of 1.7375. It also fixes the required delivery state as +NT, which means normalized and tempered, and defines the minimum spots for test samples, impact test temperature and energy rules, as well as allowed size differences. This standard also meets the unified rules of EU PED 2014/68/EU. It guarantees all forgings made to this rule meet basic safety rules for pressure units sold in Europe, with no extra material approval needed. For projects outside Europe, we can adjust production to match ASME SA-182 as the equal grade of F22, ASTM A182, API 6A with PSL 1 to 4 grades, DIN 17175 and custom material rules for special projects. We supply all needed standard papers together with each delivery batch.

Selecting the Right Melting Process for Your Application

The choice of melting route directly determines the cleanliness, hydrogen content, segregation level, and ultrasonic inspectability of the 12CrMo9-10 forging. Jiangsu Liangyi operates five distinct melting routes, and our technical team selects the appropriate route based on component thickness, NDT acceptance level, end-use environment, and customer specification. Understanding the practical differences helps customers make better procurement decisions:

1. EAF (Electric Arc Furnace) only — Suitable for general-purpose 12CrMo9-10 forgings in non-important service, section thickness up to 150mm, UT acceptance level S1E2 or below per EN 10228-3. Cost-effective for large volume orders with standard commercial requirements.
2. EAF + LF + VD (Ladle Furnace + Vacuum Degassing) — Our standard route for most pressure equipment forgings. Vacuum degassing removes dissolved hydrogen to below 1.5ppm and reduces nitrogen to below 60ppm, dramatically improving ultrasonic inspectability. Suitable for section thicknesses up to 400mm and UT level S2E3. This route covers the majority of boiler, heat exchanger, and valve applications under EN 10028-2, EN 13445, and ASME VIII.
3. EAF + ESR (Electro Slag Remelting) — ESR provides a secondary refining pass that further reduces macro-segregation, shrinkage porosity, and oxide inclusions below the capability of vacuum degassing alone. The controlled solidification in the water-cooled ESR mould produces a fine, oriented dendritic structure that yields superior and more consistent through-thickness properties. Recommended for heavy-section forgings (thickness 300–800mm), UT level S2E4 or S3E3, and applications where longitudinal/transverse property anisotropy must be minimized, such as large tube sheets and pressure vessel heads.
4. EAF + PESR (Protective-Atmosphere Electro Slag Remelting) — PESR is performed under an inert gas atmosphere (typically argon), which prevents re-oxidation of reactive alloying elements during remelting and deletes the titanium and aluminum pick-up that can occur in conventional ESR. PESR is the best choice route for 12CrMo9-10 forgings requiring the highest cleanliness levels for nuclear power secondary circuits, ultra-supercritical boiler important parts, and special applications where oxide inclusion size must be strictly controlled.
5. VIM + PESR (Vacuum Induction Melting + Protective-Atmosphere ESR) — The premium dual-vacuum route, mandated for nuclear Class 1 primary circuit parts, advanced aerospace alloys, and any application needing guaranteed hydrogen below 1.0ppm, K-series cleanliness K1 ≤ 0.5, and macro-segregation-free ingot quality. VIM deletes all dissolved gases in the primary melt; PESR then remelts the VIM electrode under protective atmosphere to achieve the finest possible inclusion morphology and solidification structure. Our in-house VIM+PESR capability is what enables us to qualify for nuclear-grade RCP forgings and the most demanding oil & gas and petrochemical important-service applications.

1.7375 (12CrMo9-10) Steel Chemical Composition — Elements & Their Metallurgical Roles

Knowing the role of each alloy element in 1.7375 (12CrMo9-10) steel and how these elements work inside the material structure helps engineers choose this steel for high-temperature pressure working conditions. The below content shows the chemical content limits from EN 10028-2:2009 for products with a standard thickness no more than 250 mm, and explains the specific metal working effect of every element in this steel. Most steel suppliers do not share such clear and detailed information. Jiangsu Liangyi keeps this open to help customers make professional and reasonable purchase choices based on solid technical facts.

Note: The above composition ranges are for heat analysis per EN 10028-2:2009, applicable to nominal thickness ≤250mm. For thicknesses 250mm–400mm and above, slightly wider tolerance bands apply to some elements. Our technical team will provide the applicable product analysis tolerance for your specific section upon request.

12CrMo9-10 (1.7375) Steel Mechanical Properties — Room Temperature & Elevated Temperature

The mechanical properties of 1.7375 (12CrMo9-10) forged steel must be considered both at room temperature (for pressure testing, handling, and cold-condition operation) and at the actual service temperature (for design stress calculation and creep life assessment). The following tables present the EN 10028-2:2009 guaranteed room-temperature properties and the corresponding elevated-temperature 0.2% proof stress values that engineers use for pressure part wall thickness calculations in accordance with EN 13480, ASME II Part D, and similar codes.

Room-Temperature Mechanical Properties (Nominal Thickness ≤ 250mm, +NT Condition)

Elevated-Temperature 0.2% Proof Stress — Rp0.2 (MPa) for Design Calculations

The following elevated-temperature proof stress values represent typical guaranteed minimum values for 1.7375 (12CrMo9-10) in +NT condition per EN 10028-2 and EN 13480-2 Annex B. These are the values used by pressure vessel and piping designers to calculate required wall thicknesses at operating temperature:

Important note: The values above are minimum guaranteed values for design purposes. Actual mean values achieved by our EAF+LF+VD production typically run 10–15% above these minima, as verified by our routine elevated-temperature tensile testing per ASTM E21 / EN ISO 6892-2. Contact our technical team for certified test report examples.

Weldability, Pre-Heat Requirements & Post-Weld Heat Treatment (PWHT) for 1.7375 (12CrMo9-10)

For fabricators and end-users, one of the most useful but least written-about things regarding 12CrMo9-10 is weldability. Specifically, this means the preheat, interpass temperature, and required post-weld heat treatment parameters needed to make strong, creep-resistant weld joints—without hydrogen cold cracking or post-weld stress relief cracking. Jiangsu Liangyi's technical team has worked with several international welding engineering companies on 12CrMo9-10 fabrication qualifications, and we summarize the key parameters below:

Carbon Equivalent & Cold Cracking Susceptibility

The International Institute of Welding (IIW) carbon equivalent formula for 1.7375 (12CrMo9-10) — CE = C + Mn/6 + (Cr+Mo+V)/5 + (Cu+Ni)/15 — usually gives a CE value of about 0.68–0.78 for this alloy. This shows that you must pre-heat the steel before any welding, no matter how thick the section is. The Pcm (Ito-Bessyo) parameter, which works better for low-carbon alloys, usually gives 0.22–0.28 for 12CrMo9-10. This means if you don’t pre-heat, there’s a high chance of cold cracking.

Recommended Welding Parameters

• Minimum preheat temperature: 200°C for section thickness ≥ 12mm; 150°C for thickness < 12mm (measured within 75mm of the weld joint, both sides)
• Maximum interpass temperature: 300°C to prevent austenite grain coarsening and delta-ferrite formation in the weld metal
• Post-weld slow cool: After welding, wrap joint in insulating blankets and cool slowly to 100°C before PWHT; do NOT allow rapid cooling to room temperature before PWHT
• PWHT temperature range: 680–720°C; hold time minimum 1 hour per 25mm thickness (minimum 2 hours); heating and cooling rates ≤ 55°C/hour above 300°C for section thickness > 50mm
• PWHT purpose: (1) Temper martensite formed in the heat-affected zone (HAZ); (2) Reduce residual welding stresses that promote stress-relief cracking; (3) Allow hydrogen to diffuse out and prevent delayed HAZ cracking; (4) Restore creep rupture properties in the HAZ to near-parent-metal level
• Filler metal recommendation: AWS ER90S-B3 (GMAW/GTAW) or AWS E9015-B3 / EN ISO 3580-A: E CrMo2 B (SMAW); matching composition filler is essential to keep creep strength continuity across the weld joint

Our forged 12CrMo9-10 parts are supplied in the +NT condition (normalized and tempered at the factory), which provides the correct base microstructure and residual stress state for fabrication. If your fabrication sequence requires PWHT simulation or step-cooling testing of our forged material prior to order placement, we can arrange coupon testing from production heats — contact our technical team to discuss requirements.

12CrMo9-10 (1.7375) vs. Related Grades: How to Choose the Right Alloy

Engineers who choose a Cr-Mo alloy steel for pressure equipment applications often evaluate 12CrMo9-10 alongside related grades. The following comparison highlights the main differentiators that should guide material choice decisions based on Jiangsu Liangyi's manufacturing and application experience:

Selection rule of thumb: If your application requires continuous operation above 480°C or involves hydrogen partial pressure above the 1Cr-0.5Mo Nelson curve limit, 1.7375 (12CrMo9-10) is the preferred ferritic Cr-Mo grade. If wall temperatures stay below 480°C and hydrogen service is at low partial pressure, 1.7335 (13CrMo4-5) may offer a cost-effective alternative. For service above 560°C, P91 (X10CrMoVNb9-1) or P92 grades with vanadium and niobium additions should be evaluated. Our technical team can assist with alloy selection for your specific design conditions — contact us at sales@jnmtforgedparts.com.

Inspection Standards, NDT Levels & Full Testing Capabilities for 1.7375 Forged Parts

Why NDT Level Selection Matters for 12CrMo9-10 Forgings

The NDT acceptance standard for 12CrMo9-10 forgings is not a random rule. It directly decides whether hidden inner flaws such as shrinkage holes, hydrogen cracks, layered defects and uneven material lines can be found and removed early. These flaws may lead to early fatigue damage or creep cracks after the part is put into use. EN 10228-3 for ultrasonic testing and EN 10228-1 for magnetic particle testing set four evaluation grades. The ultrasonic testing grades range from S1E1 to S4E4, and magnetic particle testing covers E1 to E4. Among these grades, S4E4 is the strictest one. It needs full checks for all small flaws larger than 1mm flat-bottom hole size, and allows no unqualified defects. For most 12CrMo9-10 forgings used in pressure equipment, Jiangsu Liangyi uses UT S2E3 and MT E3 as regular standards. We can also meet the higher S3E4 and E4 grades for nuclear power and key oil and gas projects. The following content introduces our full inspection capacity.

Ultrasonic Testing (UT) Capabilities

• Standard UT (conventional, immersion or contact): EN 10228-3 levels S1E1 through S3E4; ASTM A388 standard practice; calibrated reference blocks per EN 12223 and ASTM E428. Probe frequencies 1–5 MHz selected by forging section thickness and material attenuation. Straight-beam (L-wave) for volumetric inspection; angle-beam (S-wave) for surface and sub-surface zone inspection on flanges and rings.
• Phased Array UT (PAUT): Available for complex geometry forgings, large-diameter rings, and applications where conventional manual scanning cannot achieve required coverage. PAUT with 64-element linear arrays provides electronic steering and focusing, producing full-volume C-scan maps with digital record. Qualified per ASME BPVC Section V Article 4 and NF EN ISO 13588. Customers can request PAUT data files (.e-scan or similar) as part of the documentation package.
• Time-of-Flight Diffraction (TOFD): Available for specific applications requiring through-thickness flaw sizing accuracy (sizing error ≤ 1mm). TOFD is particularly valuable for heavy-section tube sheet forgings and pressure vessel nozzle forgings where weld overlays or cladding are applied after supply.
• UT qualification level: Our UT operators are qualified and trained in accordance with EN ISO 9712 requirements; specific operator certification levels are confirmed upon request for projects needing documented operator qualification.

Magnetic Particle Testing (MT)

• We carry out wet fluorescent magnetic particle testing following EN 10228-1 and ASTM A275, with acceptance grades from E1 to E4. We use the wet fluorescent testing method as our standard for all E3 and E4 checks under EN 10228-1. This method offers higher detection sensitivity than dry powder or ordinary wet testing ways. We use two magnetization types in order: circular magnetization through a conductor bar and coil-based longitudinal magnetization, to fully check all surface directions of each part.
• For ring forgings, special fixture current conductors are used to get circular magnetization through the ring bore, detecting axially oriented linear indications that longitudinal magnetization cannot reveal.

Mechanical & Chemical Testing

• Tensile testing at room temperature: EN ISO 6892-1 / ASTM E8, full-section reduced-area specimens; reports Rm, ReH (or Rp0.2), A, and Z for each heat lot
• Tensile testing at elevated temperature: EN ISO 6892-2 / ASTM E21, temperatures 100–550°C; reports Rp0.2 and Rm at each test temperature for design verification
• Charpy V-notch impact testing: EN ISO 148-1 / ASTM E23, test temperatures from -60°C to +100°C; average and individual minimum values reported per EN 10028-2 requirements
• Brinell hardness testing: EN ISO 6506-1 / ASTM E10, on every forging lot; HBW 10/3000 standard test load; hardness mapping across cross-section available for heavy-section forgings
• Chemical composition analysis: Optical emission spectrometry (OES) per EN ISO 15350; full 11-element analysis (C, Si, Mn, P, S, Cr, Mo, Ni, N, Al, Cu) plus trace elements (As, Sn, Sb, Pb, V, Nb, Ti, B) for special applications
• Metallographic analysis: Grain size determination per ASTM E112 (Heyn intercept method); inclusion content rating per DIN 50602 / ASTM E45 Method A; microstructure phase identification by optical and scanning electron microscopy (SEM)
• Creep rupture testing: ASTM E139, test temperatures 450–550°C, stress levels selected per customer specification; minimum rupture life testing for design life validation on critical pressure boundary parts
• Hydrogen analysis: Vacuum hot extraction method; quantifies dissolved H₂ in ppm weight for VD and ESR/PESR/VIM melted materials; essential for heavy-section forgings where hydrogen flaking is a risk
• NACE SSC testing: NACE TM0177 Method A (constant load tensile test in H₂S-saturated brine) for sour-service API 6A qualification

Dimensional & Visual Inspection

• 3D coordinate measuring machine (CMM) with 5-meter measurement volume for complex machined forgings
• Laser tracker measurement for large-diameter rings and tube sheets (OD up to 6,500mm)
• Digital height gauges, bore gauges, and surface roughness testers (Ra) for machined surfaces
• 100% visual inspection per EN 10228-3 Clause 5 on all delivery surfaces; forging laps, seams, cold shuts, and cracks are mandatory rejection criteria regardless of NDT acceptance level

Documentation & Traceability

Every 1.7375 forged part from Jiangsu Liangyi comes with a full set of technical papers. These papers include EN 10204 3.1 factory test reports, or 3.1 documents with third-party signing as 3.2 versions, heat treatment time and temperature curve records, NDT test files such as ultrasonic scan reports, magnetic test records and size check reports. Every single piece is marked with a heat number to ensure full material traceability. For nuclear power and special working conditions, we also provide complete quality files that record all production control steps from raw billet incoming to final packing. We keep all test and inspection records for at least 10 years after shipment.

Related Alloy Steel Grades for Pressure Equipment Forgings

Beyond 1.7375 (12CrMo9-10), Jiangsu Liangyi manufactures custom forged parts in a full range of pressure equipment alloy steels. If your project needs a different grade, explore our complete forging material grades, including commonly specified grades such as:

• 1.7380 (10CrMo9-10 / 10CrMo910) — Lower carbon Cr-Mo steel, EN 10028-2, widely used in boiler and pressure vessel applications
• 1.7335 (13CrMo4-5 / 13CrMo45) — Classic Cr-Mo alloy for boiler drums, steam pipes and heat exchangers
• 1.4922 (X20CrMoV12-1) — High-temperature martensitic stainless for power plant turbines and steam headers
• P91 / P92 (9Cr-1Mo-V) — Advanced creep-resistant steels for supercritical and ultra-supercritical boilers
• ASTM A182 F22 (2.25Cr-1Mo) — ASME pressure boundary alloy for valves, flanges and fittings

Contact our technical team at sales@jnmtforgedparts.com to discuss the optimal alloy grade for your specific pressure and temperature requirements.

Frequently Asked Questions About 1.7375 (12CrMo9-10) Forged Parts

Contact Jiangsu Liangyi for Custom 1.7375 (12CrMo9-10) Forging Solutions

Our technical sales team — staffed by engineers with direct forging process expertise — responds to all technical inquiries within 24 hours. When you contact us, please include: (1) part drawing or sketch with main dimensions; (2) applicable standard (EN 10028-2, ASTM A182 F22, API 6A, or project spec); (3) required NDT level and certificate type; (4) quantity and target delivery date. The more detail you provide, the faster and more accurately we can quote. For urgent projects, please call our direct WhatsApp line for immediate response.