How LIBS Fits into API 578 Updates

David Mercuro
David Mercuro

The trade association - American Petroleum Institute (API) - has generated over 700 Recommended Practices (RP) and standards throughout the years. These practices and methods assist the petroleum (upstream, downstream and midstream), chemical and power industries to follow a consistent set of measurement methodologies to enhance operational safety, environmental efficiency and sustainability in the oil and gas industries.

API 578 provides the guidelines to verify that the nominal elemental composition of alloy components within the pre-piping system are consistent with the selected or specified construction material. This process provides insurance against catastrophic release of toxic or hazardous liquids/vapors.  API RP 578 is the Recommended Practice (RP) for Positive Material Identification (PMI) and covers performing on a consistent basis elemental analysis/alloy grade determination via the following spectroscopies: X-Ray Fluorescence (XRF), Optical Emission Spectroscopy (OES) and Laser Induced Breakdown Spectroscopy (LIBS).

The API revisits existing Recommended Practices every 5 years. The original API RP 578 was generated 13 years ago and the 3rd edition was released in February 2018.

4 Key changes for this latest API 578 edition include:

1. Original title – “Guidelines for a Material Verification Program for New and Existing Pipelines” changed to “Guidelines for a Material Verification Program for New and Existing Assets."  API 578 now covers all metallic materials (not just piping products) found in the entire oil and gas industry.

2. Anchors utilized to secure refractory material such as refractory bricks, fiber or gunned, on refractory materials found in a furnace are now covered in the 3rd edition of 578.  These anchors require high alloy materials to withstand the elevated temperatures found in these refractory lined vessels/furnace systems.

3. The addition of LIBS has been added to the document. This includes Rigaku’s KT-100S and KT-500 (for the analysis of carbon), which are now included as acceptable measurement tools to assist with PMI and to support a Material Verification Program (MVP).

4. As a request by the Chemical Safety Board (CSB), the word “shall” has replaced the word “may” throughout the document.  With this change the industries must now establish a Material Verification Program. No longer is it suggested that the owner/user "may establish a program, now it is "shall" (requirement) to implement a program.

Trust, but Verify

The changes within the 3rd edition of API RP 578 are substantial. “Trust, but Verify” all your metallic alloy components is required. This requirement is applicable throughout the supply change. It applies to materials purchased for use either directly by the owner/user or indirectly by distributers, fabricators, machine shops and contractors. The verification of alloy composition now must be performed numerous times throughout the supply change process. “Trust, but Verify” is the mandate regarding alloy chemical composition confirmation. If you have an Material Test Report (MTR), you can no longer just it on good faith. Instead, the requirement is to perform a current PMI analysis via instruments stipulated in the 3rd addition, which include the Rigaku portfolio of handheld KT LIBS metal analyzers