POSITIVE MATERIAL IDENTIFICATION (PMI)
Positive Material Identification (PMI) provides alloy chemistry and grade ID information instantly using a handheld tube-based analyzer without having to transport, alter, or damage the material. PMI is also used to ensure that the parent material in vessels and pipe spools is composed of the correct composition (i.e., 304 or 316L) and once the component is welded that the correct filler material was used.
PMI verification is used to dedicate material or components that were purchased "commercial grade" without having the extra cost associated with purchasing "safety related" components and material. When used in combination with the receipt inspection process, PMI also ensures that the base material of piping and vessels meets the design specification and/or purchase order requirements.
When repairs are made to existing vessels and piping, a PMI test can quickly verify the material composition to ensure that the correct welding procedures and consumables are selected for use.
With Positive Material Identification (PMI) the alloy composition, and thus, the identity of materials can be determined. If a material certificate is missing or/and you need to be certain about the type of material used, PMI as an NDT method is the best solution. Positive Material Identification is particularly used for high quality metals like stainless steel and high alloy metals.