A4 Stainless Steel BSP Pipe Thread Fittings are stocked to ISO 228 (G). The grade provides superior, including marine and chloride environments and is largely non-magnetic; the practical service range is approx. -200 °C to +400 °C. Property data, grade comparison and the full size table follow.
Why Choose A4 Stainless Steel for BSP Pipe Thread Fittings
Specified for marine, coastal and chemical applications. For bsp pipe thread fittings, this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A4-80 (316) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Superior, including marine and chloride environments |
Corrosion Behavior in Service
A4 (316) adds 2–3% molybdenum to the A2 (304) composition, which dramatically improves resistance to chloride-pitting corrosion. For BSP Pipe Thread Fittings in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Galvanic & Galling Considerations
Two important notes for stainless bsp pipe thread fittings: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Sizes of BSP Pipe Thread Fittings Available in A4 Stainless Steel
| Size | Nominal size (in) | Major diameter (mm) | Pitch (mm) | Threads per inch (TPI) | Tap drill (mm) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| G1/16 | 1/16 | 7.723 | 0.907 | 28 | 6.8 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1/8 | 1/8 | 9.728 | 0.907 | 28 | 8.8 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1/4 | 1/4 | 13.157 | 1.337 | 19 | 11.5 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G3/8 | 3/8 | 16.662 | 1.337 | 19 | 15.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1/2 | 1/2 | 20.955 | 1.814 | 14 | 18.5 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G5/8 | 5/8 | 22.911 | 1.814 | 14 | 20.5 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G3/4 | 3/4 | 26.441 | 1.814 | 14 | 24.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G7/8 | 7/8 | 30.201 | 1.814 | 14 | 27.5 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1 | 1 | 33.249 | 2.309 | 11 | 30.5 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1-1/8 | 1-1/8 | 37.897 | 2.309 | 11 | 35.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1-1/4 | 1-1/4 | 41.91 | 2.309 | 11 | 39.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1-1/2 | 1-1/2 | 47.803 | 2.309 | 11 | 45.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G1-3/4 | 1-3/4 | 53.746 | 2.309 | 11 | 51.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G2 | 2 | 59.614 | 2.309 | 11 | 57.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G2-1/4 | 2-1/4 | 65.71 | 2.309 | 11 | 63.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G2-1/2 | 2-1/2 | 75.184 | 2.309 | 11 | 72.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G2-3/4 | 2-3/4 | 81.534 | 2.309 | 11 | 79.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G3 | 3 | 87.884 | 2.309 | 11 | 85.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G3-1/2 | 3-1/2 | 100.33 | 2.309 | 11 | 97.5 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G4 | 4 | 113.03 | 2.309 | 11 | 110.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G5 | 5 | 138.43 | 2.309 | 11 | 135.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |
| G6 | 6 | 163.83 | 2.309 | 11 | 160.0 | ISO 228-1 / DIN ISO 228 | Parallel pipe thread (G), sealed by gasket |