Pipe-Lok Vales & Fittings Company delivers precision-engineered instrumentation fittings and valves trusted for reliability, safety, and performance in industrial applications with a strong focus on engineering excellence and quality control.
Engineered for highly corrosive acid and chloride environments. Alloy 28 pressure relief valves combine high nickel, chromium and molybdenum content for strong resistance to sulfuric acid, phosphoric acid and chloride-bearing process media.
High-Performance Flow & Safety Instrumentation Solutions
Alloy 28 is a high-alloy austenitic material with strong resistance to acid and chloride corrosion.
| Element | Weight Percentage (%) |
|---|---|
| Nickel (Ni) | 30.0 - 34.0 |
| Chromium (Cr) | 26.0 - 28.0 |
| Iron (Fe) | Balance |
| Molybdenum (Mo) | 3.0 - 4.0 |
| Copper (Cu) | 0.6 - 1.4 |
| Carbon (C) | 0.030 max |
| Manganese (Mn) | 2.50 max |
| Silicon (Si) | 1.00 max |
| Nitrogen (N) | 0.11 max |
*Composition limits are indicative for the listed grade family; applicable product specifications may vary depending on valve component and product form.
Alloy 28 offers useful strength and excellent corrosion resistance in acid and chloride-containing environments.
| Property | Typical / Minimum Value |
|---|---|
| Tensile Strength | 500 MPa min |
| 0.2% Yield Strength | 214 MPa min |
| Elongation | 40% min |
| Hardness | Approx. 220 HB max |
| Density | Approx. 8.0 g/cm3 |
*Mechanical requirements depend on product form, heat treatment and applicable ASTM/ASME specification. Confirm final values against the material specification used for the pressure relief valve component.
High-performance material specifications for our complete Pressure Relief Valve range.
Designed for demanding pressure systems where material compatibility, corrosion resistance and reliable pressure protection are essential.
Selected for phosphoric acid production and handling systems.
Used in sulfuric acid service where Alloy 28 compatibility is preferred.
Suitable for sour and chloride-bearing production environments.
Reliable in acidic chloride and mixed chemical process streams.
Used in acid and phosphate processing lines.
Applicable for chloride-rich industrial environments.
Pipe-Lok Vales & Fittings manufactures high-quality alternatives to the following standard industry part numbers
| Swagelok Part No. | Pipe-Lok Vales & Fittings Equivalent | Availability |
|---|---|---|
| SS-4R3A | Available | Ready to Ship |
| SS-4R3A1 | Available | Ready to Ship |
| SS-4R3A5 | Available | Ready to Ship |
| SS-4R3A5-BU | Available | Ready to Ship |
| SS-4R3A5-EP | Available | Ready to Ship |
| SS-4R3A5-KZ | Available | Ready to Ship |
| SS-4R3A5-NE | Available | Ready to Ship |
| SS-4R3A5-RT | Available | Ready to Ship |
| SS-4R3A-BU | Available | Ready to Ship |
| SS-4R3A-EP | Available | Ready to Ship |
| SS-4R3A-KZ | Available | Ready to Ship |
| SS-6R3A-MM | Available | Ready to Ship |
| SS-8R3A-MM | Available | Ready to Ship |
| SS-R4M8F8 | Available | Ready to Ship |
| SS-R4M8S8 | Available | Ready to Ship |
| SS-R4S8 | Available | Ready to Ship |
| SS-R4S12MM | Available | Ready to Ship |
| SS-RL3M4-F4 | Available | Ready to Ship |
| SS-RL3M4F4-RT | Available | Ready to Ship |
| SS-RL3M4-S4 | Available | Ready to Ship |
| SS-RL3S4 | Available | Ready to Ship |
| SS-RL3S4-SC11 | Available | Ready to Ship |
| SS-RL3S4-EP | Available | Ready to Ship |
| SS-RL3S4-MO | Available | Ready to Ship |
| SS-RL3S4-KZ-11002 | Available | Ready to Ship |
| SS-RL3S6MM | Available | Ready to Ship |
| SS-RL3S8MM | Available | Ready to Ship |
| SS-RL4M8F8 | Available | Ready to Ship |
| SS-RL4MR8 | Available | Ready to Ship |
| SS-RL4S8 | Available | Ready to Ship |
| SS-RL4S12MM | Available | Ready to Ship |