Alloy know-how behind every valve
Over more than four decades of valve design and manufacture, the founder of Controtek built deep knowledge of metallurgy and foundry technology, and developed valves in special alloys – duplex and super duplex steel, Hastelloy, Ni-Cr-Mo alloys and all austenitic stainless steels – in India at a time when such valves were otherwise imported. That expertise is why Controtek offers almost every valve type in stainless and duplex grades.
Stainless steel valves
Austenitic stainless steels – ASTM A351 CF8 (304), CF3 (304L), CF8M (316), CF3M (316L) and CN7M (Alloy 20), plus forged A182 F304/F316 grades – handle most acids, alkalis, solvents and hygienic fluids and remain tough at very low temperatures.
Duplex stainless steel valves
Duplex grades such as ASTM A890 1A, 1B, 1C, 2A, 3A and 4A have about twice the strength of 316 and far better resistance to chloride stress corrosion cracking – suited to brackish water, chemical and offshore service.
Super duplex stainless steel valves
Super duplex grades such as ASTM A890 5A and 6A are specified for seawater, brine and the most aggressive chloride environments, including desalination and offshore oil & gas.
Valve types available in SS, duplex and super duplex
| Valve | Stainless steel | Duplex / super duplex |
|---|---|---|
| Globe valves | SS globe valves | Super duplex globe valves |
| Gate valves | Yes | Yes |
| Ball valves | Yes | Yes |
| Butterfly valves | Yes | Yes |
| Knife gate valves | Yes | Yes |
| Diaphragm valves | Yes | Yes |
| Swing check valves | Yes | Yes |
| Dual plate check valves | Yes | Yes |
| Forged valves | F304/F316/L grades | Yes |
| Strainers | Yes | Yes |
Material and trim pairings are listed in the material of construction chart.
