Immersion probes with sapphire optics
This Hellma immersion probe withstands extreme process conditions and due to its monolithic sapphire head this probe is the ideal solution for highest demands.
This Hellma immersion probe withstands extreme process conditions and due to its monolithic sapphire head this probe is the ideal solution for highest demands.
These probes have a monolithic probe head made of high-purity sapphire (Al2O3). By using a total reflection prism, the light beam passes through the sample only once, as with a cuvette measurement. The stray light is minimised.
| Type | 661.2300 NIR; 661.2302 NIR |
| Sensing head material | Sapphire (Al2O3) |
| Probe barrel material | Stainless steel 1.4571 (316 Ti) or Material 2.4602 (Hastelloy® C-22) |
| Flange | Without |
| Sealing of sensing head | Perfluoroelastomer FFKM (ASTM D1418) Fluoropolymer PTFE (ASTM D1600) |
| Outer-Ø | 20 or 25 mm |
| Total length (inl. SMA socket) | 353 mm |
| Max. immersion depth | 240 mm |
| Typ. transmission | NIR: > 40% in air at 1,500 nm |
| Max. pressure | 35 bar |
| Max. temperature | 260 °C |
| Optic fibre | Firmly installed, can be changed at Hellma NIR 400 nm – 2300 nm (25,000 cm-1– 4.348 cm-1) UV/Vis and UV/Vis low solarisation upon request. |
| Type | 661.2303 NIR |
| Sensing head material | Sapphire (Al2O3) |
| Probe barrel material | Stainless steel 1.4571 (316 Ti) or Material 2.4602 (Hastelloy® C-22) |
| Flange | DIN 25 / PN 40 Form A* |
| Sealing of sensing head | Perfluoroelastomer FFKM (ASTM D1418) Fluoropolymer PTFE (ASTM D1600) |
| Outer-Ø | 25 mm |
| Total length | 353 mm |
| Max. immersion depth | 200 mm |
| Typ. transmission | NIR: > 40% in air at 1,500 nm |
| Max. pressure | 35 bar (at max. 100°C)* |
| Max. temperature | 260 °C (at max. 25 bar)* |
| Optic fibre | Firmly installed, can be changed at Hellma NIR 400 nm – 2300 nm (25,000 cm-1– 4.348 cm-1) |
* according to EN 1092-1
