Types, applications and standards of carbon steel reducers
Contents
- Preface
- What is a carbon steel reducer?
- Types of carbon steel reducers
- Material classification of carbon steel reducers
- Advantages and disadvantages of carbon steel reducers
- Applications of carbon steel reducers
- ASTM specifications for carbon steel reducers
- Differences between carbon steel and stainless steel reducers
- Complete guide to carbon steel reducer dimensions
- Summary
Preface
Carbon steel reducers are essential connectors commonly used in industrial piping systems, widely applied in industries such as petroleum, chemical, and power.
This article will provide a detailed introduction to carbon steel reducers, covering their definition, advantages and disadvantages, applications, and standards.
For more videos on carbon steel reducer production, please follow us on YouTube and LinkedIn.
What is a carbon steel reducer?
Carbon steel reducers are pipe fittings used in piping systems to connect pipes of different diameters, and are usually made of carbon steel.
Types of carbon steel reducers
Carbon steel concentric reducers have their inlet and outlet located on the same centerline. Compared to eccentric reducers, they are less expensive to manufacture and suitable for most pipe installations.
Carbon steel eccentric reducers have one end offset from the centerline for use in horizontal pipes, preventing cavitation or liquid accumulation.
Material classification of carbon steel reducers
Carbon steel reducer materials: 10#, 20#, A3, Q235B, 20G, 16Mn, ASTM A234, ASTM A105, Q345B, etc.
Advantages and disadvantages of carbon steel reducers
Carbon steel reducers offer advantages such as low cost, good mechanical properties, and ease of processing, but also have disadvantages including limited corrosion resistance, heavier weight, susceptibility to rust, and high thermal conductivity.
When selecting carbon steel reducers, it is necessary to comprehensively consider their advantages and disadvantages based on the specific application environment and requirements, weighing the pros and cons to choose the appropriate material.
For applications with high requirements for corrosion resistance and weight, reducers made of other materials such as stainless steel can be considered.
Applications of carbon steel reducers
Petrochemical industry: Transporting media such as oil, gas, and water.
Power industry: Boiler and piping systems.
Municipal engineering: Water supply and drainage, HVAC systems.
ASTM specifications for carbon steel reducers
Chemical Properties
| Grade | C | Si | Mn | P | S | Cr | Ni | Mo |
| WPL6 | 0.30 | 0.15-0.40 | 0.50-1.35 | 0.035 | 0.040 | 0.30 | 0.40 | 0.12 |
| WPL9 | 0.20 | / | 0.40-1.06 | 0.030 | 0.030 | / | 1.60-2.24 | / |
| WPL3 | 0.20 | 0.13-0.37 | 0.31-0.64 | 0.05 | 0.05 | / | 3.2-3.8 | / |
| WPL8 | 0.13 | 0.13-0.37 | 0.90 | 0.030 | 0.030 | / | 8.4-9.6 | / |
Mechanical Properties
| Grade | T.S. | Y.S. | EL. |
| WPL6 | 415-655 | 240 | 22 |
| WPL9 | 435-610 | 315 | 20 |
| WPL3 | 450-620 | 240 | 22 |
| WPL8 | 690-865 | 515 | 16 |
Differences between carbon steel and stainless steel reducers
| Feature | Carbon Steel Reducing Tee | Stainless Steel Reducing Tee |
| Corrosion Resistance | Poor. Prone to rust in humid, oxygenated, or chloride-containing environments. Requires protection (e.g., galvanizing, painting). | Excellent. Forms a protective chromium oxide layer, resisting water, steam, weak acids/alkalis, and chlorides. |
| Typical Applications | Dry air, neutral water, or short-term use in non-corrosive environments. | Chemical processing, marine, food & beverage, wastewater treatment. |
| Tensile Strength | Generally higher (e.g., Q235: 370-500 MPa). Suitable for high-pressure, large-diameter pipes. | Good. Strength can be increased via cold working (e.g., 304: ~520 MPa). |
| Low-Temperature Toughness | Good, remains tough at low temperatures. | Excellent, maintains toughness in both high and low-temperature environments. |
| High-Temperature Resistance | Requires heat-resistant coatings. Performance degrades. | Excellent. 304: suitable for ≤800°C; 310S: suitable for ≤1150°C. |
| Initial Cost | Low (approx. 1/3 to 1/2 the cost of stainless steel). | High. |
| Long-Term Cost | Higher maintenance costs (regular rust removal, repainting, part replacement). | Lower lifecycle cost in corrosive environments due to minimal maintenance. |
| Hygiene & Safety | Rust can contaminate media. Internal linings/coatings may peel. | Smooth surface inhibits bacterial growth. Complies with food and pharmaceutical standards. |
Summary of Recommended Applications
| Scenario | Recommended Material | Key Reason |
| Coastal Water Supply (low chloride) | Stainless Steel (316L) | Superior corrosion resistance; 20+ year lifespan. |
| Chemical Plant (weak acid, pH 4-6) | Stainless Steel (304) | Resists weak acid corrosion; 10+ year lifespan. |
| Indoor Dry Compressed Air | Carbon Steel | Cost-effective; sufficient performance in dry environments. |
| High-Temp Steam Boiler (300°C) | Stainless Steel (310S) | Superior high-temperature resistance and longevity. |
Complete guide to carbon steel reducer dimensions
| Nominal Size | Outside Diameter at Bevel | End to End | |
| DN | NPS | OD×OD | H |
| 20×15 | 3/4×1/2 | 26.7×21.3 | 38 |
| 25×20 | 1×3/4 | 33.4×26.7 | 51 |
| 32×25 | 1 1/4×1 | 42.2×33.4 | 51 |
| 40×32 | 1 1/2×1 1/4 | 48.3×42.2 | 64 |
| 50×40 | 2×1 1/2 | 60.3×48.3 | 76 |
| 65×50 | 2 1/2×2 | 73.0×60.3 | 89 |
| 80×65 | 3×2 1/2 | 88.9×73.0 | 89 |
| 90×80 | 3 1/2×3 | 101.6×88.9 | 102 |
| 100×90 | 4×3 1/2 | 114.3×101.6 | 102 |
| 125×100 | 5×4 | 141.3×114.3 | 127 |
| 150×125 | 6×5 | 168.3×141.3 | 140 |
| 200×150 | 8×6 | 219.1×168.3 | 152 |
| 250×200 | 10×8 | 273.0×219.1 | 178 |
| 300×250 | 12×10 | 323.8×273.0 | 203 |
| 350×300 | 14×12 | 355.6×323.8 | 330 |
| 400×350 | 16×14 | 406.4×355.6 | 356 |
| 450×400 | 18×16 | 457.0×406.4 | 381 |
| 500×450 | 20×18 | 508.0×457.0 | 508 |
| 550×500 | 22×20 | 559.0×508.0 | 508 |
| 600×550 | 24×22 | 610.0×559.0 | 508 |
| 650×600 | 26×24 | 660.0×610.0 | 610 |
| 700×650 | 28×26 | 711.0×660.0 | 610 |
| 750×700 | 30×28 | 762.0×711.0 | 610 |
| 800×750 | 32×30 | 813.0×762.0 | 610 |
| 850×800 | 34×32 | 864.0×813.0 | 610 |
| 900×850 | 36×34 | 914.0×864.0 | 610 |
| 950×900 | 38×36 | 965.0×914.0 | 610 |
| 1000×950 | 40×38 | 1016.0×965.0 | 610 |
| 1050×1000 | 42×40 | 1067.0×1016.0 | 610 |
| 1100×1050 | 44×42 | 1118.0×1067.0 | 610 |
| 1150×1100 | 46×44 | 1168.0×1118.0 | 711 |
| 1200×1150 | 48×46 | 1219.0×1168.0 | 711 |
| 1300×1200 | 52×48 | 1321.0×1219.0 | 711 |
| 1400×1300 | 56×52 | 1422.0×1321.0 | 711 |
| 1500×1400 | 60×56 | 1524.0×1422.0 | 711 |
Summary
Through the above introduction, we have gained a more comprehensive understanding of carbon steel reducers.
This knowledge will help us better select and use carbon steel reducers, and also provides valuable reference for professionals in related industries.
In the future, with the advancement of technology and industrial development, the application of carbon steel reducers will become more widespread, and related technologies will continue to be updated and improved.
We hope this article has helped everyone gain a deeper understanding of carbon steel reducers.
