ABB (2013) Pressure Measurement Corrosion and material selection
ABB (2013) Pressure Measurement Corrosion and material selection

AISI 316 L stainless steel.
The AISI 316 L ss is the standard material for the wetted parts of ABB 2600T family of transmitters; it has a good resistance to corrosion, including low concentrations of nitric acid and most salt solutions with some exception like nonoxidizing acids such as hydrochloric, hydrofluoric, sulfuric and phosphoric.The resistance of AISI 316 L ss to alkaline solutions, organic acids, and other organic compounds may depend on temperature.Concerning salts, the halide salts (fluorine, chlorine, bromine, iodine) can cause severe pitting and possibly stress-corrosion cracking.
In case of hydrogen sulphide (H2S) that is often present in oil/gas production, the AISI 316 L ss may be available with a specific certificate: NACE MR0175, see the applicable data sheets. This standard applies in case of sufficient partial pressure of H2S in gas, i.e. as an example a total process pressure of 400 kPa and concentration of H2S at least above 700 ppm, or a process pressure of 26 MPa and concentration of H2S above 10 ppm. This standard assures the prevention of sulphide stress corrosion cracking, by reducing the stress, i.e. by means of a low hardness of the construction material and a suitable manufacturing process of the transmitter.Non wetted part like bolts are also covered by this standard since they affect the effectiveness of containment of the whole instrument even if they are exposed to H2S far below the limit of applicability of the mentioned NACE standard.The NACE certificate is in general available for Monel, Hastelloy C and Tantalum.For UREA grade applications, a specific certificate is available for AISI 316 L ss: ASTM A262, practice C, Huey test.

ABB-2013-Pressure-Measurement-Corrosion-and-material-selection.pdf

ABB (2013) Pressure Measurement Corrosion and material selection
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