Durable Alloy Steel Circles & Rings – Supplied in Grades ASTM A387 Gr 5, 9, 11, 12, 22, 91 – Types include Forged Rings, Rolled Rings, and Precision Machined Circles – Finishes: Polished, Black, and Shot Blasted – Suitable for Pressure Vessels, Gear Blanks, and Structural Components.
These circles and rings find broad application in the manufacture of flanges, valves, heavy equipment parts, and structural components across key industries including oil & gas, petrochemicals, power plants, and automotive sectors. Their superior mechanical properties — such as high tensile strength, fatigue endurance, and weldability — make them ideal for use in extreme pressure and temperature conditions, ensuring long-lasting performance and safety.
We specialize in manufacturing and supplying premium Alloy Steel Circles and Rings, designed to fulfill the rigorous demands of heavy industrial applications. Utilizing state-of-the-art forging, cutting, and heat treatment techniques, our products deliver exceptional strength, durability, and precise dimensions. Produced according to globally recognized standards like ASTM A387 and EN 10083, these alloy steel components are trusted for their reliability in challenging operational environments.
We cater primarily to markets in Europe, Russia, Saudi Arabia, Oman, Qatar, and the USA, where there is robust demand for durable alloy steel circles and rings. Our services include tailored manufacturing, competitive pricing, and reliable delivery schedules to meet diverse project needs. Committed to quality and customer satisfaction, we are your dependable partner for alloy steel components built to international standards.
Our Alloy Steel Circles and Rings are available in a wide size range, featuring thicknesses from 5 mm up to 80 mm and diameters spanning 100 mm to 2500 mm. We provide various popular alloy grades such as ASTM A387 Grade 1, 5, 9, 11, 22, 91, and EN 10083-3 Grade 42CrMo4, known for their excellent resistance to corrosion, high temperature, and wear. Each batch is supplied with detailed mill test certificates (MTC) to ensure traceability and compliance with quality benchmarks.
Alloy Steel Circles & Rings – Supplied as Forged Rings, Machined Circles, Spacer Rings, and Flange Blanks – Available in OD sizes from 10mm to 600mm, Thickness 5mm to 100mm – Manufactured to ASTM A387 Chrome Moly and DIN Standards.
Alloy Steel Circles & Rings Specifications
| Product | Alloy Steel Circles & Rings |
| Grades | A387 Gr 5 / 9 / 11 / 12 / 22 / 91 Class 1 & 2, EN 10028-2 P235GH / P265GH / 16Mo3 |
| Standards | ASTM A204, ASTM A387 EN 10028, IS 2041, ASME, DIN, EN Series |
| Size Range | Diameter: 10mm to 500mm (0.4” to 20”) Thickness: 5mm to 100mm |
| Form | Solid Circles, Forged Rings, Rolled Rings, Machined Rings |
| Types | Hot Rolled, Cold Rolled, Forged, Precision Machined, Heat Treated |
| Surface Finish | Black, Bright, Polished, Shot Blasted, Rough Machined |
| Manufacturing Methods | Forging, Rolling, Heat Treatment, CNC Machining |
| Applications | Automotive, Aerospace, Heavy Engineering, Oil & Gas, Machinery Parts |
| Properties | High Strength, Toughness, Corrosion Resistance, Weldability, Fatigue Resistance |
| Certifications | ISO 9001:2015, EN 10204 3.1, NACE MR0175, PED 2014/68/EU |
Types of Alloy Steel Circles & Rings
Blank Circles / Discs
Supplied in custom diameters and thicknesses as per client specifications.
Flange Rings
Rings used as components for flanges in piping systems, pressure vessels, etc.
Gasket Rings
Gasket Rings are Available in standard and custom sizes as per ASME or DIN specifications.
Spacer Rings
Rings used to maintain space between mechanical parts commonly used in equipment.
Washer Rings
Smaller rings used as washers for load distribution under bolts and nuts.
Split Rings
C-shaped or snap-fit rings used to hold assemblies in grooves or shafts.
Profile Cut Rings
Custom-shaped rings cut from plates using CNC, laser, or waterjet, for specific machinery.
Forged Rings
Heavy-duty rings forged for strength, used in aerospace, marine industry or heavy machinery.
Equivalent of Chrome Moly Circles
| ASTM | EN / DIN | JIS | BS | IS (Indian Standard) |
|---|---|---|---|---|
| A387 Gr 11 Cl 1/2 | 13CrMo4-5 | SCMV3 | 621B | 15CrMo5 |
| A387 Gr 12 Cl 1/2 | 10CrMo9-10 | SCMV4 | 621C | 12CrMo9 |
| A387 Gr 22 Cl 1/2 | 10CrMo910 | SCM415 | 621D | 13CrMo910 |
| A387 Gr 5 Cl 1/2 | 5CrMo | SCM2 | 621A | 5CrMo |
| A387 Gr 9 Cl 1/2 | 9CrMo | SCM3 | 621AA | 9CrMo |
| A204 Gr A/B | 16Mo3 | SPV315 | 621 | 16Mo3 |
Chemical Composition of Alloy Steel Rings
| C | Mn | P | S | SI | Cr | Mo | |
| Grade 5 | 0.15 max | 0.3 – 0.6 | 0.035 | 0.03 | 0.5 max | 4.00 – 6.00 | 0.45 – 0.65 |
| Grade 9 | 0.15 max | 0.30 – 0.6 | 0.03 | 0.03 | 1.0 max | 8.0 – 10.0 | 0.9 – 1.1 |
| Grade 11 | 0.05 – 0.17 | 0.4 – 0.65 | 0.035 | 0.035 | 0.5 – 0.80 | 1.0 – 1.5 | 0.45 – 0.65 |
| Grade 12 | 0.05 – 0.17 | 0.4 – 0.65 | 0.035 | 0.035 | 0.15 – 0.4 | 0.8 – 1.15 | 0.45 – 0.6 |
| Grade 22 | 0.05 – 0.15 | 0.3 – 0.6 | 0.035 | 0.035 | 0.5 max | 2.0 – 2.5 | 0.9 – 1.1 |
Mechanical Properties of Alloy Steel Circles & Rings
| Tensile Strength
(ksi) |
Tensile Strength
(MPa) |
Yield Strength
(ksi) |
Yield Strength (MPa) | Elongation
in 2 inches (%) |
||
| A 387 Grade 5 | Class 1 | 60-85 | 415-585 | 30 | 205 | 18 |
| Class 2 | 75-100 | 515-690 | 45 | 310 | 18 | |
| A 387 Grade 9 | Class 1 | 60-85 | 415-585 | 30 | 205 | 18 |
| Class 2 | 75-100 | 515-690 | 45 | 310 | 18 | |
| A 387 Grade 11 | Class 1 | 60-85 | 415-585 | 35 | 240 | 22 |
| Class 2 | 70-90 | 485-620 | 45 | 310 | 22 | |
| A 387 Grade 12 | Class 1 | 50-80 | 380-550 | 33 | 230 | 22 |
| Class 2 | 65-85 | 450-585 | 40 | 275 | 22 | |
| A 387 Grade 22 | Class 1 | 60-85 | 415-585 | 30 | 205 | 18 |
| Class 2 | 75-100 | 515-690 | 45 | 310 | 18 | |
Dimension Chart of Chrome Moly Circles
| Diameter (mm) | Diameter (inches) | Thickness (mm) | Thickness (inches) |
|---|---|---|---|
| 10 | 0.4″ | 5 | 0.2″ |
| 50 | 2″ | 10 | 0.4″ |
| 100 | 4″ | 20 | 0.8″ |
| 200 | 8″ | 30 | 1.2″ |
| 300 | 12″ | 50 | 2″ |
| 400 | 16″ | 75 | 3″ |
| 500 | 20″ | 100 | 4″ |
| 600 | 24″ | 125 | 5″ |
| 800 | 32″ | 150 | 6″ |
| 1000 | 40″ | 150 | 6″ |
| 1200 | 48″ | 150 | 6″ |
| 1500 | 60″ | 150 | 6″ |
| 1800 | 72″ | 150 | 6″ |
| 2000 | 80″ | 150 | 6″ |
Alloy Steel Rings Weight Chart
| Diameter (mm) | Thickness (mm) | Approx. Weight (kg) |
|---|---|---|
| 100 | 10 | 6.16 |
| 200 | 20 | 49.26 |
| 300 | 30 | 139.63 |
| 400 | 50 | 308.43 |
| 500 | 75 | 573.56 |
| 600 | 100 | 942.48 |
| 800 | 125 | 1,963.50 |
| 1000 | 150 | 3,540.00 |
| 1500 | 150 | 7,965.00 |
| 2000 | 150 | 14,132.00 |
Worldwide Supply of Alloy Steel Circles & Rings
Russia, Bahrain, Cyprus, Egypt, Iran, Iraq, Israel, Jordan, Kuwait, Lebanon, Oman, Palestine, Qatar, Saudi Arabia, Syria, Turkey, United Arab Emirates (UAE), Yemen, United States of America (USA), Albania, Andorra, Austria, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Moldova, Monaco, Montenegro, Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Ukraine, United Kingdom, Vatican City.
