Tubewell Steel & Engg. Co. is a leading manufacturer and stockist specializing in Alloy Steel Pipes, Tubes, Fittings and Flanges for critical industrial applications.
Chrome-moly and nickel-chrome-moly round bars in AISI 4140, 4130, EN19, EN24 and ASTM A182 F11 / F22 for shafts, forgings and high-strength machined components.
Tubewell Steel & Engg. Co. is a stockist and supplier of alloy steel round bars in Mumbai, India. We carry AISI 4140 and 4130 chrome-moly bars, EN19 and EN24 engineering steels, and ASTM A182 F11 / F22 forged bars for flange and fitting blanks – supplied annealed, normalized or hardened and tempered, cut to your length.
High-strength, hardenable alloy bars for engineering and pressure parts
Alloy steel round bars contain controlled additions of chromium, molybdenum and, in some grades, nickel. These elements dramatically improve hardenability, so the bars can be quenched and tempered to high strength and toughness through large sections. AISI 4140 and its British equivalent EN19 are the workhorse medium-carbon chrome-moly steels for shafts, gears and bolting; AISI 4130 offers a lower carbon level for better weldability; and EN24 (≈ AISI 4340) adds 1.5% nickel for the highest strength and toughness in heavy sections.
For pressure-retaining components, we also supply ASTM A182 F11 and F22 forged bars, which are machined into flanges, forged fittings, valve bodies and tube-sheets for high-temperature service. All bars are sourced from approved mills, identified by heat number, ultrasonically tested on request and supplied with EN 10204 3.1 mill test certificates. Saw cutting, peeling, turning and heat treatment to your required hardness are available from our Mumbai facility.
Standard supply range for alloy steel round bars
| Parameter | Details |
|---|---|
| Standards | ASTM A29 / A29M, ASTM A322, ASTM A331, ASTM A434, ASTM A182 (forged bars), SAE J404, BS 970, EN 10083-3 |
| Grades | AISI 4130, AISI 4140, EN19 (709M40), EN24 (817M40), ASTM A182 F11, F22 |
| Diameter | 10 mm to 300 mm (larger forged sizes on request) |
| Forms | Round Bar, Square Bar, Hex Bar, Flat Bar, Forged Blocks, Rings, Shafts |
| Production | Hot Rolled, Forged, Cold Drawn |
| Length | 3 m to 6 m random, or saw cut to required length |
| Supply Condition | Annealed, Normalized, Normalized & Tempered, Hardened & Tempered (Q&T) |
| Surface Finish | Black, Peeled, Rough Turned, Bright, Centreless Ground, Polished |
| Tolerance | As per ASTM A29; h9 / h10 / h11 for bright bars |
| Straightness | Max. 1 mm per metre (closer on request) |
| Ultrasonic Testing | SEP 1921, ASTM A388, EN 10228-3 |
| Testing | Chemical, Tensile, Hardness, Impact, Grain Size, Inclusion Rating, Macro Etch, PMI |
| Certificates | EN 10204 3.1 / 3.2, TPI Reports |
Nearest international equivalents of our round bar grades
| Grade | AISI / ASTM | UNS | EN | W.Nr. | JIS | BS 970 |
|---|---|---|---|---|---|---|
| 4130 | AISI 4130 | G41300 | 25CrMo4 | 1.7218 | SCM430 | – |
| 4140 | AISI 4140 | G41400 | 42CrMo4 | 1.7225 | SCM440 | 708M40 |
| EN19 | ≈ AISI 4140 | – | 42CrMo4 | 1.7225 | SCM440 | 709M40 |
| EN24 | ≈ AISI 4340 | G43400 | 34CrNiMo6 | 1.6582 | SNCM439 | 817M40 |
| F11 Bar | ASTM A182 F11 | K11572 | 13CrMo4-5 | 1.7335 | – | – |
| F22 Bar | ASTM A182 F22 | K21590 | 11CrMo9-10 | 1.7383 | – | – |
Weight %, as per ASTM A29 / BS 970 / ASTM A182 (chips show AISI 4140)
| Grade | C | Mn | P | S | Si | Cr | Mo | Ni |
|---|---|---|---|---|---|---|---|---|
| AISI 4130 | 0.28 – 0.33 | 0.40 – 0.60 | 0.035 max | 0.040 max | 0.15 – 0.35 | 0.80 – 1.10 | 0.15 – 0.25 | – |
| AISI 4140 | 0.38 – 0.43 | 0.75 – 1.00 | 0.035 max | 0.040 max | 0.15 – 0.35 | 0.80 – 1.10 | 0.15 – 0.25 | – |
| EN19 (709M40) | 0.36 – 0.44 | 0.70 – 1.00 | 0.035 max | 0.040 max | 0.10 – 0.40 | 0.90 – 1.20 | 0.25 – 0.35 | – |
| EN24 (817M40) | 0.36 – 0.44 | 0.45 – 0.70 | 0.035 max | 0.040 max | 0.10 – 0.40 | 1.00 – 1.40 | 0.20 – 0.35 | 1.30 – 1.70 |
| A182 F11 Cl.2 | 0.10 – 0.20 | 0.30 – 0.80 | 0.040 max | 0.040 max | 0.50 – 1.00 | 1.00 – 1.50 | 0.44 – 0.65 | – |
| A182 F22 Cl.3 | 0.05 – 0.15 | 0.30 – 0.60 | 0.040 max | 0.040 max | 0.50 max | 2.00 – 2.50 | 0.87 – 1.13 | – |
Typical values by condition (F11 / F22 are A182 minimums)
| Grade & Condition | Tensile Strength | Yield Strength (0.2%) | Elongation | Hardness (HB) |
|---|---|---|---|---|
| 4130 Annealed | 560 MPa | 460 MPa | 21.5% | ≤ 217 |
| 4130 Normalized | 670 MPa | 435 MPa | 25.5% | 197 |
| 4140 Annealed | 655 MPa | 415 MPa | 25.7% | 197 |
| 4140 Q&T (28–32 HRC) | 930 – 1080 MPa | 750 MPa min | 12% min | 271 – 301 |
| EN19 Q&T (T condition) | 850 – 1000 MPa | 680 MPa min | 13% min | 248 – 302 |
| EN24 Q&T (T condition) | 850 – 1000 MPa | 650 MPa min | 13% min | 248 – 302 |
| A182 F11 Cl.2 | 485 MPa min | 275 MPa min | 20% min | 143 – 207 |
| A182 F22 Cl.3 | 515 MPa min | 310 MPa min | 20% min | 156 – 207 |
Typical values for 4130 / 4140 chrome-moly bars (for reference)
| Property | Metric | Imperial |
|---|---|---|
| Density | 7.85 g/cm³ | 0.284 lb/in³ |
| Melting Point (approx.) | 1416 – 1432 °C | 2580 – 2610 °F |
| Modulus of Elasticity | 205 GPa | 29.7 × 10³ ksi |
| Shear Modulus | 80 GPa | 11.6 × 10³ ksi |
| Poisson's Ratio | 0.29 | 0.29 |
| Thermal Conductivity | 42.6 W/m·K | 24.6 BTU/h·ft·°F |
| Mean Thermal Expansion (0–100°C) | 12.2 µm/m·°C | 6.8 µin/in·°F |
| Specific Heat | 0.47 J/g·°C | 0.11 BTU/lb·°F |
Theoretical weight of alloy steel round bars – weight (kg/m) = D² × 0.006165
| Diameter (mm) | Diameter (inch, approx.) | Weight (kg/m) | Weight per 6 m Bar (kg) |
|---|---|---|---|
| 10 | 0.39 | 0.62 | 3.70 |
| 12 | 0.47 | 0.89 | 5.33 |
| 16 | 0.63 | 1.58 | 9.47 |
| 20 | 0.79 | 2.47 | 14.80 |
| 25 | 0.98 | 3.85 | 23.12 |
| 30 | 1.18 | 5.55 | 33.29 |
| 32 | 1.26 | 6.31 | 37.88 |
| 36 | 1.42 | 7.99 | 47.94 |
| 40 | 1.57 | 9.86 | 59.18 |
| 45 | 1.77 | 12.48 | 74.90 |
| 50 | 1.97 | 15.41 | 92.48 |
| 55 | 2.17 | 18.65 | 111.89 |
| 60 | 2.36 | 22.19 | 133.16 |
| 65 | 2.56 | 26.05 | 156.28 |
| 70 | 2.76 | 30.21 | 181.25 |
| 75 | 2.95 | 34.68 | 208.07 |
| 80 | 3.15 | 39.46 | 236.74 |
| 90 | 3.54 | 49.94 | 299.62 |
| 100 | 3.94 | 61.65 | 369.90 |
| 110 | 4.33 | 74.60 | 447.58 |
| 120 | 4.72 | 88.78 | 532.66 |
| 130 | 5.12 | 104.19 | 625.13 |
| 140 | 5.51 | 120.83 | 725.00 |
| 150 | 5.91 | 138.71 | 832.28 |
| 160 | 6.30 | 157.82 | 946.94 |
| 180 | 7.09 | 199.75 | 1198.48 |
| 200 | 7.87 | 246.60 | 1479.60 |
| 220 | 8.66 | 298.39 | 1790.32 |
| 250 | 9.84 | 385.31 | 2311.88 |
| 280 | 11.02 | 483.34 | 2900.02 |
| 300 | 11.81 | 554.85 | 3329.10 |
Weights are theoretical, based on a density of 7.85 g/cm³ (D in mm). Actual weights may vary within mill tolerances and with surface finish.
Where alloy steel round bars are used
Drill collars, tool joints, subs, valve stems and wellhead parts.
Axles, crankshafts, steering knuckles and transmission gears.
Shafts, spindles, couplings, pinions and machine components.
High-tensile studs, bolts and nuts for pressure flanges.
F11 / F22 bar for flanges, forged fittings and valve bodies.
4130 structural parts, landing gear and ordnance components.
Quality you can verify on every heat
Large inventory for fast dispatch
MTC EN 10204 3.1 / 3.2
Positive material identification
Pan-India & export shipping
Quick answers about alloy steel round bars
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