Visit the API Publications store today. Search for "RP 551," select the PDF with multi-user license if needed, and elevate your process measurement standards to the industry’s gold standard. Disclaimer: This article is for informational purposes only. Always refer to the latest official edition of any API Recommended Practice for actual engineering decisions. Prices and edition dates are subject to change.
Project engineers use Section 4.3.2 to specify the correct pressure transmitter turndown ratio. The RP recommends limiting turndown to 10:1 for DP transmitters to avoid exceeding 0.1% of span drift—a detail frequently missed by junior engineers. api rp 551 pdf
During a refinery shutdown, maintenance teams reference Table 6 (Level Diagnostic Checks) to systematically test displacer cages for corrosion pitting. The RP suggests radiography of level bridles every 6 years. Visit the API Publications store today