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SS 440C
SS 440C: Specifications | Grades & Standards | Product Types | Equivalent | Chemical | Mechanical | BW Fittings | Forged Fittings | Flanges | FAQ
Manufacturers & Exporters of 440C pipe fittings, SS 440C flanges, stainless steel 440C fittings, forged 440C fittings, buttweld 440C fittings, UNS S44004, ASTM A182 440C. Delivering High-Strength, Corrosion-Resistant, and Heat-Tolerant Piping Solutions Exported to Japan, South Korea, Singapore, Thailand, and Malaysia.
Best Export Prices: sales@midlandforgefittings.com
Midland Forge and Fittings Pvt. Ltd is a leading manufacturer, supplier, and exporter of high-quality stainless steel 440C pipe fittings, flanges. Our company specializes in engineered piping solutions that meet international standards, including ASTM, ASME, and UNS, ensuring corrosion resistance, heat tolerance, and mechanical strength for demanding industrial applications.
Our company operates with a precision-focused production process, using advanced forging, machining, and fabrication technologies. Each product undergoes strict quality control at every stage, including material inspection, dimensional checks, and certification compliance, to guarantee consistent performance and reliability.
Stainless Steel 440C is a high-carbon, high-chromium martensitic stainless steel known for its exceptional hardness, wear resistance, and moderate corrosion resistance. With chromium content around 16–18% and carbon content between 0.95–1.20%, it can be hardened through heat treatment to achieve superior strength and durability.
440C is commonly used in pipe fittings, flanges, valves, bearings, and industrial components where precision, durability, and resistance to abrasion are critical. It meets international standards such as ASTM A182, ASTM A276, and UNS S44004, ensuring dimensional accuracy, high strength, and heat tolerance. While its corrosion resistance is slightly lower than austenitic grades like SS 304 or 316, its hardness and mechanical stability make it suitable for industrial, petrochemical, and high-wear applications where long-term performance under stress is required.
For packaging and shipping, we use robust protective packaging to prevent damage during transit, including wooden crates, pallets, and secure wrapping. Products are shipped worldwide using reliable logistics partners, ensuring timely delivery to clients across various industries, including oil & gas, petrochemical, power generation, and marine sectors.
With a customer-centric approach, the company provides technical guidance, custom solutions, and after-sales support, making it a trusted partner for industrial buyers and contractors seeking durable, high-strength, and precision-engineered piping solutions.
440C Stainless steel Forged Fittings - Specifications
Size Range – (Buttweld, Forged, Flange)
Pressure Rating/ Wall Thickness
Applications
ASTM / ASME
ASTM/ASME A403/SA403
Grades, EN, UNS
Quality Certifications
Dimensional Standards
Forms
Surface Finish
UNS S44004 Pipe Fittings – Grades & Standards
| Material / Grade | UNS | ASTM / ASME Standard | Product Type | Typical Applications |
|---|---|---|---|---|
| SS 440C | S44004 | ASTM A182 / A182M (Forged & Flanges), ASTM A403 / A403M (Buttweld Fittings), ASTM A276 (Bars & Rods) | Forged Fittings, Flanges, Buttweld Fittings | High-Strength Valves, Bearings, Pump Shafts, Heat-Treated Components, Petrochemical Equipment, Wear-Resistant and High-Load Industrial Applications |
SS 440C Series – Industrial Flanges, Fittings & Piping Products
ASTM A182 SS 440C Flanges - Equivalent Grades
| Specification | Stainless Steel 440C |
|---|---|
| Material | Stainless Steel |
| Grade / UNS | 440C / UNS S44004 |
| ASTM / ASME | ASTM A240 / A276 / A182 |
| EN / DIN | X105CrMo17 / 1.4125 |
| JIS | SUS440C |
| GOST | 95Х18 / 40Х13 |
| BS | 440C / BS 970 |
| AFNOR | Z100CD17 |
Stainless Steel 440C Industrial Pipe Fittings - Chemical Composition
| Element | Percentage (%) |
|---|---|
| Carbon (C) | 0.95 – 1.20 |
| Chromium (Cr) | 16.0 – 18.0 |
| Manganese (Mn) | ≤ 1.00 |
| Silicon (Si) | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.040 |
| Sulfur (S) | ≤ 0.030 |
| Nickel (Ni) | ≤ 0.75 |
| Molybdenum (Mo) | ≤ 0.75 |
SS 440C ASTM A403 Pipe Fittings - Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength | 760 – 1000 MPa |
| Yield Strength (0.2% Proof) | ≥ 450 MPa |
| Elongation | ≥ 14% |
| Hardness (Brinell) | Up to 285 HB (Annealed) / Up to 600 HB (Hardened) |
| Density | 7.74 g/cm³ |
| Melting Point | 1480°C (2700°F) |
| Modulus of Elasticity | 200 GPa |
| Thermal Conductivity | 24.2 W/m·K at 100°C |
| Specific Heat Capacity | 460 J/kg·K |
High-Strength SS 440C Buttweld Pipe Fittings – Seamless, Welded & Fabricated Types
440C Stainless Steel ASTM A182 Flanges
Heat-Treated Stainless Steel 440C Forged Fittings – Complete Guide
What is Stainless Steel 440C, and why is it used for pipe fittings and flanges?
Stainless Steel 440C is a high-carbon martensitic stainless steel that offers a unique balance of hardness, wear resistance, and corrosion resistance, making it ideal for high-stress industrial components.
Composition: 440C contains approximately 16–18% chromium and 0.95–1.20% carbon, which allows it to be heat-treated to achieve high hardness (up to 58–60 HRC).
Performance: After hardening and tempering, it delivers excellent mechanical strength and superior wear resistance, suitable for abrasive and high-pressure environments.
Applications: Commonly used for flanges, buttweld and forged fittings, valve parts, and high-wear mechanical assemblies in petrochemical, power generation, and process industries.
How does Stainless Steel 440C differ from other stainless steel grades like 410 or 420?
While all three grades (410, 420, and 440C) belong to the martensitic stainless steel family, they differ in composition and mechanical characteristics:
SS 410: Offers good corrosion resistance and moderate strength, suitable for general-purpose fittings.
SS 420: Higher carbon than 410, providing better hardness and wear resistance.
SS 440C: Contains the highest carbon content, resulting in maximum hardness, tensile strength, and wear resistance, ideal for precision, high-load applications.
Thus, 440C is preferred for premium fittings and flanges that must endure abrasion, impact, and cyclic loading.
What precautions should be taken during machining and welding of SS 440C?
Because of its high hardness and carbon content, machining and welding require specific care:
Machining: Should be performed in the annealed condition using carbide tools, slow speeds, and adequate lubrication.
Welding: Generally not recommended for hardened 440C due to the risk of cracking; if unavoidable, preheating and post-weld annealing are essential.
Surface Finishing: Polishing or passivation is recommended to enhance corrosion resistance.
Global Destinations for Stainless Steel 440C Fittings & Flanges Exports
United Arab Emirates (UAE), Saudi Arabia, Oman, Qatar, Kuwait, Bahrain, Iraq, Jordan, Lebanon, Yemen, Iran, Israel, Germany, United Kingdom (UK), Italy, France, Spain, Netherlands, Myanmar, Singapore, Malaysia, Indonesia, Vietnam, South Korea, Philippines, Thailand, Bangladesh, Sri Lanka, Papua New Guinea, United States (USA), Canada, Brazil, Chile, Argentina, Colombia, Russia, Ukraine, Kazakhstan, Poland, Egypt, Algeria, Morocco, Tunisia, Libya, Nigeria, Ghana, Ivory Coast, Senegal, Cameroon, Gabon, Democratic Republic of Congo, Kenya, Tanzania, Uganda, Ethiopia, Rwanda, Zambia, South Africa, Mozambique, Namibia, Botswana