All stainless steel 316L welded wetted parts pressure transmitter for measuring hydrogen gas. The DMP336 is purposely designed for H2 applications which require 316L stainless steel to reduce hydrogen embrittlement of pressure containment components over time, and all welded seals to prevent the leaking of hydrogen gas molecules into the internal electronics housing or the surrounding environment.
- Pressure Range: 0…16 bar g up to 0…1000 bar g
- Output Signals: 4-20mA, 2 wire
- Accuracy: 0.5% full scale
- Electrical Connections: M12x1 4 pin connector, IP67 cable gland
- Process Connections: G1/2, G1/4 EN837, 1/4 NPT male
- Media Compatibility: All welded stainless steel 316L
- Special Features: H2 gas compatibility, oil and grease free to ISO 15001 for oxygen use
- Special Options: ATEX/IECEx intrinsic safety
The use of a thick stainless steel sensing element prevents problems due to hydrogen permeation, where H+ ions can migrate through thin materials such as isolation diaphragm in oil filled silicon pressure sensors. Over time H+ ions will re-combine to form H2 gas molecules which become trapped behind the isolation diaphragm which will eventually causes gas pockets to form within the oil fill causing a shift in sensor calibration.
The DMP 336 wetted parts are manufactured from 316L stainless steel which is the recommended material to use with hydrogen gas to reduce the embrittlement process caused by the absorption of hydrogen ions, and mechanical stresses from high gas pressures.
Hydrogen gas has the smallest molecule, and therefore is the most likely gas to leak through joints and seals. To ensure a high integrity leak tight seal, all materials which are in contact with the hydrogen gas are welded.