Ashford Instrumentation Ltd

NACE MR0175

Pressure Gauges According To NACE MR0175 Requirements

National Association of Corrosive Engineers (NACE) is a worldwide technical organisation which studies various aspects of corrosion and the damage that may result in refineries, chemical plants, water systems and other industrial systems.

The NACE Standard MR0175, “Sulphide Stress Corrosion Cracking Resistance Metallic Materials for Oil Field Equipment” is widely used throughout the world. The standard specifies the proper materials, heat treat conditions and strength levels required to provide good service life in sour gas and oil environments. MR0175 was first issued in 1975 and is intended to apply only to oil field equipment, flow line equipment and other oil field processing facilities where Hydrogen Sulphide is present.

It is worth noting that while the standard is intended only to be used for oil field equipment, industry has taken MR0175 and applied it to many other areas including refineries, LNG plants, pipelines and natural gas systems where it is also possible that hydrogen sulphide could be present.

Various metals can be specially treated to meet the hardness requirement of MR0175 including carbon steel, some limited cast irons and more commonly stainless steel. Not all of these material can be successfully used however to manufacture bourdon tubes which need to retain a high degree of flexibility. Because of this most pressure gauge manufacturers will use either Monel or Stainless Steel 316Ti for the wetted parts when constructing pressure gauges to meet MR0175.

Special documentation of materials to MR0175 is not required by the standard and NACE does not issue any type of certification. It is the manufacturers responsibility to properly monitor the materials and processes as required by MR0175. Pressure gauges meeting the requirements of MR0175 will have the dial marked accordingly. 3.1b Material Certificates can also be supplied on request but please note these must always be requested at the time of order as no guarantee can be made that they can be retrospectively supplied.