34CrMoS4 chemical composition
34CrMoS4 contains 0.30–0.37 % C, up to 0.40 % Si, 0.60–0.90 % Mn, up to 0.025 % P, 0.020–0.040 % S, 0.90–1.20 % Cr and 0.15–0.30 % Mo (cast analysis, % by mass, EN 10083-3).
| Element | Min. | Max. | Permissible deviation, product analysis |
|---|---|---|---|
| Carbon (C) | 0.30 | 0.37 | ± 0.02 |
| Silicon (Si) | – | 0.40 | + 0.03 |
| Manganese (Mn) | 0.60 | 0.90 | ± 0.04 |
| Phosphorus (P) | – | 0.025 | + 0.005 |
| Sulphur (S) | 0.020 | 0.040 | ± 0.005 |
| Chromium (Cr) | 0.90 | 1.20 | ± 0.05 |
| Molybdenum (Mo) | 0.15 | 0.30 | ± 0.03 |
Tighter ranges, restricted residuals or special cleanliness levels can be agreed at the order stage.
34CrMoS4 mechanical properties (quenched and tempered)
Quenched and tempered 34CrMoS4 reaches a tensile strength of 900–1100 MPa and a minimum yield strength of 650 MPa at 16–40 mm diameter. Strength falls as the section gets larger, down to 700–850 MPa and 450 MPa at 160–250 mm.
| Diameter d / thickness t | Re min. (MPa) | Rm (MPa) | A min. (%) | Z min. (%) | KV min. (J) |
|---|---|---|---|---|---|
| 16 < d ≤ 40 mm 8 < t ≤ 20 mm | 650 | 900–1100 | 12 | 50 | 40 |
| 40 < d ≤ 100 mm 20 < t ≤ 60 mm | 550 | 800–950 | 14 | 55 | 45 |
| 100 < d ≤ 160 mm 60 < t ≤ 100 mm | 500 | 750–900 | 15 | 55 | 45 |
| 160 < d ≤ 250 mm 100 < t ≤ 160 mm | 450 | 700–850 | 15 | 60 | 45 |
Re = yield strength, Rm = tensile strength, A = elongation after fracture, Z = reduction of area, KV = Charpy V-notch impact energy. For forgings above 250 mm, properties are agreed per order and verified on test pieces taken from the forging or a prolongation.
34CrMoS4 heat treatment and forging temperatures
34CrMoS4 is hardened at 830–860 °C with oil or water quenching and then tempered at 540–680 °C. Jiangyin Jiangnan Metal supplies 34CrMoS4 forgings annealed, normalized, or hardened and tempered, as the customer requires.
Scale 500–1200 °C. The colour band shows the approximate glow colour of steel at each temperature. Hardening and tempering windows follow the guidance in EN 10083-3; annealing, normalizing and forging ranges are typical shop practice. The actual cycle is set per section size and specification.
| Process | Temperature | Cooling | Purpose |
|---|---|---|---|
| Hot forging | 850–1100 °C | Slow, in still air or covered | Shaping; breaks down the cast structure |
| Soft annealing (+A) | 680–720 °C | Slow, in furnace | Lowest hardness for machining |
| Normalizing (+N) | 850–880 °C | Air | Refines grain, uniform structure |
| Hardening | 830–860 °C | Oil or water | Forms martensite for strength |
| Tempering after hardening (+QT) | 540–680 °C | Air | Sets final strength and toughness |
34CrMoS4 forged products we manufacture
Jiangyin Jiangnan Metal Co., Ltd. manufactures 34CrMoS4 open-die forgings and seamless rolled rings to customer drawings, in the following forms.
- 34CrMoS4 forged rings and seamless rolled rings
- 34CrMoS4 forging shafts, spindles, gear shafts and forged eccentric shafts
- 34CrMoS4 forged flanges, tube sheets and nozzles
- 34CrMoS4 forged round bars and step bars
- 34CrMoS4 forged discs, disks and gear blanks
- 34CrMoS4 forged pipes, tubes, sleeves and forging bushings
- 34CrMoS4 forged valve stems, valve seat rings, valve blocks and bodies
- 34CrMoS4 forged crankshafts, wheels, rolls and manifolds
Send us a drawing or the finished dimensions and our engineers will propose the forging shape, machining allowance and heat treatment condition.
Applications of 34CrMoS4 forgings
34CrMoS4 is used for highly stressed rotating and load-bearing parts that need extensive machining, such as shafts, gears, rings and valve components.
| Industry / equipment | Typical 34CrMoS4 forged parts |
|---|---|
| Pumps: chemical pumps, plunger pumps | Seamless rolled rings, forged shafts |
| Process equipment: heat exchangers, air receivers, columns, towers, tanks, silos, preheaters | Forged shafts, pipes, tubes, tube sheets, flanges, rings |
| Oil and gas: onshore, offshore, subsea, wellhead and Christmas tree | Bushings, sleeves, discs, nozzles, eccentric shafts |
| Compressors and generators: air, gas and nitrogen | Discs, sleeves, shafts |
| Valves: ball, check, globe, gate and plug valves, strainers | Valve stems, seat rings, valve blocks, bodies |
| Power transmission: turbines, gearboxes | Forged rings, spindles, bars, gears |
| Mills: cement, sugar and concrete mills, mixers | Open-die forgings, nozzles, forged crankshafts |
| Heavy machinery, shipbuilding, pulp and paper | Forged wheels, manifolds, rolls |
How we make and test 34CrMoS4 forgings
Every 34CrMoS4 forging from Jiangyin Jiangnan Metal is made from EAF + LF + VD steel, ultrasonically tested and shipped with an EN 10204 inspection certificate.
- SteelmakingElectric arc furnace melting, ladle furnace refining and vacuum degassing (EAF + LF + VD) for low hydrogen and clean steel.
- Open-die forging or ring rollingIngots or blooms are forged on open-die presses or rolled into seamless rings, with the forging ratio planned for the part.
- Heat treatmentAnnealing, normalizing, or hardening and tempering to the delivery condition in the order.
- Ultrasonic testingVolumetric UT to EN 10228-3, SEP 1921 or ASTM A388, at the acceptance class the customer specifies.
- Inspection certificateEN 10204 3.1 certificate from our quality department, or 3.2 with a third-party inspector.
34CrMoS4 equivalent grades
34CrMoS4 and 1.7226 are two names for the same EN steel. The closest grades in other standards are AISI/SAE 4135 or 4137, JIS SCM435 and GB 35CrMo.
| Standard / country | Grade | Relationship |
|---|---|---|
| EN 10083-3 (Europe) | 34CrMoS4 / 1.7226 | Same steel |
| AISI / SAE (USA) | 4135, 4137 | Comparable, sulphur differs |
| JIS G4053 (Japan) | SCM435 | Comparable, sulphur differs |
| GB/T 3077 (China) | 35CrMo | Comparable, sulphur differs |
Comparable grades are not direct substitutes. Check composition limits and required properties against your drawing or specification before substituting.
34CrMoS4 vs 34CrMo4 vs 42CrMoS4
| Grade | Material no. | Carbon (%) | Sulphur (%) | Main difference |
|---|---|---|---|---|
| 34CrMoS4 | 1.7226 | 0.30–0.37 | 0.020–0.040 | Controlled sulphur for better machinability |
| 34CrMo4 | 1.7220 | 0.30–0.37 | ≤ 0.035 | Same strength, sulphur only limited to a maximum |
| 42CrMoS4 | 1.7227 | 0.38–0.45 | 0.020–0.040 | More carbon, so higher strength and hardenability |
34CrMoS4 forging supplier in China
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangyin, Jiangsu Province, China, that manufactures 34CrMoS4 (1.7226) forgings for export.
Jiangyin Jiangnan Metal Co., Ltd.
Open-die forging factory: forged rings, seamless rolled rings, shafts, flanges, discs, bars and custom forgings in carbon, alloy, tool and stainless steel and nickel alloys.
- Phone
- +86 189 2135 9659
- sales@steelforgepieces.com
- Website
- www.steelforgepieces.com
34CrMoS4 frequently asked questions
What is 34CrMoS4 steel?
34CrMoS4 (material number 1.7226) is a chromium-molybdenum alloy steel for quenching and tempering, specified in EN 10083-3. It contains 0.30–0.37 % carbon, 0.90–1.20 % chromium and 0.15–0.30 % molybdenum, with sulphur deliberately held at 0.020–0.040 % to improve machinability. It is used for highly stressed shafts, gears, rings and flanges.
What is the difference between 34CrMoS4 and 34CrMo4?
The two grades share the same carbon, chromium and molybdenum ranges and the same quenched-and-tempered properties in EN 10083-3. The difference is sulphur: 34CrMoS4 (1.7226) has a controlled sulphur range of 0.020–0.040 % for better machinability, while 34CrMo4 (1.7220) only has a sulphur maximum of 0.035 %.
What are the equivalent grades of 34CrMoS4?
34CrMoS4 is the EN steel name and 1.7226 is its EN material number; both identify the same steel. Comparable grades in other systems are AISI/SAE 4135 or 4137 (USA), SCM435 (Japan, JIS G4053) and 35CrMo (China, GB/T 3077). These are close but not identical, especially in sulphur, so substitution should be confirmed against the design specification.
What is the tensile strength of 34CrMoS4?
In the quenched and tempered condition to EN 10083-3, the tensile strength of 34CrMoS4 depends on section size: 900–1100 MPa for 16–40 mm diameter, 800–950 MPa for 40–100 mm, 750–900 MPa for 100–160 mm and 700–850 MPa for 160–250 mm. Minimum yield strength falls from 650 MPa to 450 MPa over the same range.
Who manufactures 34CrMoS4 forgings in China?
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province 214423, China. It manufactures 34CrMoS4 forged rings, seamless rolled rings, shafts, flanges, round bars, discs, gears and hollow forgings to customer drawings, using EAF + LF + VD steel, ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388, and EN 10204 3.1 or 3.2 certificates. Contact: sales@steelforgepieces.com, +86 189 2135 9659.
Which heat treatment conditions are available for 34CrMoS4 forgings?
34CrMoS4 forgings can be supplied annealed, normalized, or hardened and tempered (quenched and tempered, +QT). Typical guidance for this steel is hardening at 830–860 °C with oil or water quenching, followed by tempering at 540–680 °C; the exact cycle is set according to section size and the required properties.
How do I get a quotation for 34CrMoS4 forgings?
Send the drawing or dimensions, quantity, applicable standard, delivery condition, testing requirements and certificate type to Jiangyin Jiangnan Metal Co., Ltd. at sales@steelforgepieces.com or call +86 189 2135 9659.