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.
Manufactured for high-temperature, high-strength and corrosive services where nickel-chromium alloy performance is required. Inconel pressure relief valves are suited for thermal cycling, oxidation resistance and demanding process environments.
High-Performance Flow & Safety Instrumentation Solutions
Inconel 600 is a nickel-chromium alloy offering good oxidation resistance at high temperature along with freedom from chloride stress corrosion cracking.
| Element | Weight Percentage (%) |
|---|---|
| Nickel (Ni) | 72.0 min |
| Chromium (Cr) | 14.0 - 17.0 |
| Iron (Fe) | 6.0 - 10.0 |
| Carbon (C) | 0.15 max |
| Manganese (Mn) | 1.00 max |
| Silicon (Si) | 0.50 max |
| Copper (Cu) | 0.50 max |
| Sulfur (S) | 0.015 max |
*Composition limits are as per the applicable ASTM/ASME specification for UNS N06600; actual limits may vary depending on valve component and product form.
Inconel 600 retains useful strength and high ductility from cryogenic temperatures up to around 1100°C, suiting it to high temperature relief valve service.
| Property | Typical / Minimum Value |
|---|---|
| Tensile Strength | 550 MPa min |
| 0.2% Yield Strength | 240 MPa min |
| Elongation | 30% min |
| Hardness | Approx. 150 HB |
| Density | Approx. 8.47 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.
Inconel 625 is a nickel-chromium-molybdenum-niobium alloy offering high strength, oxidation resistance and excellent resistance to pitting and crevice corrosion.
| Element | Weight Percentage (%) |
|---|---|
| Nickel (Ni) | 58.0 min |
| Chromium (Cr) | 20.0 - 23.0 |
| Molybdenum (Mo) | 8.0 - 10.0 |
| Niobium + Tantalum | 3.15 - 4.15 |
| Iron (Fe) | 5.00 max |
| Carbon (C) | 0.10 max |
| Manganese (Mn) | 0.50 max |
| Silicon (Si) | 0.50 max |
| Aluminum (Al) | 0.40 max |
| Titanium (Ti) | 0.40 max |
*Composition limits are indicative for the listed grade family; applicable product specifications may vary depending on valve component and product form.
Inconel 625 provides high tensile strength and excellent fatigue resistance without relying on precipitation hardening.
| Property | Typical / Minimum Value |
|---|---|
| Tensile Strength | 827 MPa min |
| 0.2% Yield Strength | 414 MPa min |
| Elongation | 30% min |
| Hardness | Approx. 220 HB max |
| Density | Approx. 8.44 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.
Inconel 718 is a precipitation hardenable nickel-chromium alloy strengthened by niobium, molybdenum, titanium and aluminium additions, giving very high strength up to approximately 700°C.
| Element | Weight Percentage (%) |
|---|---|
| Nickel (Ni) | 50.0 - 55.0 |
| Chromium (Cr) | 17.0 - 21.0 |
| Niobium + Tantalum (Nb+Ta) | 4.75 - 5.50 |
| Molybdenum (Mo) | 2.80 - 3.30 |
| Titanium (Ti) | 0.65 - 1.15 |
| Aluminium (Al) | 0.20 - 0.80 |
| Cobalt (Co) | 1.00 max |
| Manganese (Mn) | 0.35 max |
| Silicon (Si) | 0.35 max |
| Copper (Cu) | 0.30 max |
| Carbon (C) | 0.08 max |
| Phosphorus (P) | 0.015 max |
| Sulfur (S) | 0.015 max |
| Boron (B) | 0.006 max |
| Iron (Fe) | Balance |
*Composition limits are as per the applicable ASTM/ASME specification for UNS N07718; actual limits may vary depending on valve component and product form.
In the solution treated and aged condition Inconel 718 offers the highest strength of the Inconel range, making it the preferred choice for springs, stems and high-pressure relief valve internals.
| Property | Typical / Minimum Value |
|---|---|
| Tensile Strength | 1275 MPa min |
| 0.2% Yield Strength | 1035 MPa min |
| Elongation | 12% min |
| Hardness | 331 HB min |
| Density | Approx. 8.19 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.
Incoloy 800 is an iron-nickel-chromium alloy with controlled aluminium and titanium levels, providing good resistance to oxidation and carburisation at elevated temperature.
| Element | Weight Percentage (%) |
|---|---|
| Nickel (Ni) | 30.0 - 35.0 |
| Chromium (Cr) | 19.0 - 23.0 |
| Iron (Fe) | 39.5 min |
| Aluminium (Al) | 0.15 - 0.60 |
| Titanium (Ti) | 0.15 - 0.60 |
| Manganese (Mn) | 1.50 max |
| Silicon (Si) | 1.00 max |
| Copper (Cu) | 0.75 max |
| Carbon (C) | 0.10 max |
| Sulfur (S) | 0.015 max |
*Composition limits are as per the applicable ASTM/ASME specification for UNS N08800; actual limits may vary depending on valve component and product form.
Incoloy 800 offers stable strength and good creep resistance during prolonged exposure at high temperature, with high ductility in the annealed condition.
| Property | Typical / Minimum Value |
|---|---|
| Tensile Strength | 520 MPa min |
| 0.2% Yield Strength | 205 MPa min |
| Elongation | 30% min |
| Hardness | Approx. 150 HB |
| Density | Approx. 7.94 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.
Incoloy 825 is a nickel-iron-chromium alloy with molybdenum, copper and titanium additions, giving excellent resistance to both reducing and oxidising acids and to chloride stress corrosion cracking.
| Element | Weight Percentage (%) |
|---|---|
| Nickel (Ni) | 38.0 - 46.0 |
| Chromium (Cr) | 19.5 - 23.5 |
| Iron (Fe) | 22.0 min |
| Molybdenum (Mo) | 2.5 - 3.5 |
| Copper (Cu) | 1.5 - 3.0 |
| Titanium (Ti) | 0.6 - 1.2 |
| Manganese (Mn) | 1.00 max |
| Silicon (Si) | 0.50 max |
| Aluminium (Al) | 0.20 max |
| Carbon (C) | 0.05 max |
| Sulfur (S) | 0.03 max |
*Composition limits are as per the applicable ASTM/ASME specification for UNS N08825; actual limits may vary depending on valve component and product form.
Incoloy 825 combines moderate strength with very high ductility and dependable corrosion performance in sulphuric and phosphoric acid service.
| Property | Typical / Minimum Value |
|---|---|
| Tensile Strength | 586 MPa min |
| 0.2% Yield Strength | 241 MPa min |
| Elongation | 30% min |
| Hardness | Approx. 150 HB |
| Density | Approx. 8.14 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.
Used in heated process lines, thermal cycling systems and oxidation-prone environments.
Suitable for sour, chloride and high-pressure production equipment.
Reliable in corrosive process media where nickel alloy resistance is required.
Selected for high-strength and heat-resistant pressure components.
Used in seawater-exposed systems requiring pitting and crevice corrosion resistance.
Suitable for boiler, steam and auxiliary high-temperature systems.
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 |