Pressure Relief Systems
The Equity Engineering Group (E2G) is a leader in developing technologies that manage risk. Our engineers have been involved with the API’s Pressure Relieving Subcommittee for over 15 years and are internationally recognized for their expertise in the area of pressure relief system design and installation. For the past 10 years, Phil Henry, P.E. has served as the task force chairman for the development of API Std. 520, "Sizing, Selection, and Installation of Pressure-Relieving Devices in Refineries."
E2G is the API-certified trainer for a 3-day Pressure Relieving Systems course, covering API Std’s 520, 521 and 2000. API certification ensures that training meets the highest standards of professional quality worldwide.
View Training Brochure (PDF).
Our pressure relieving experts can assist clients with:
- Assessment of existing relief systems for adequate overpressure protection utilizing the current industry standards from ASME and API. If deficiencies are found, we will recommend options to bring the system into compliance.
- Analysis of relief valve performance concerns, e.g. chattering, nuisance lifting, failure to lift and recommendation of remediation methods to rectify the RV’s functionality.
- Audits of pressure relieving systems to provide assurance that the methodology and engineering analysis used in the design is in compliance with "Recognized and Generally Accepted Good Engineering Practice", or RAGAGEPS.
- Design of new relieving systems to provide adequate and economical overpressure protection; note that over-sized relief protection may be just as detrimental as an under-sized system.
These tasks require extensive knowledge of the mechanical design of the various pressure relieving devices, process piping fluid dynamics (liquid, vapor and 2-phase) and a working familiarity with the latest industrial pressure relief guidelines and standards. Our experts have the required experience in these areas to provide proficient and reliable consulting regarding relief device applications.
In addition to, or as a part of these services, our experts can perform:
- Assessments of a heat exchanger internal failure relating to the credibility of considering a full tube rupture as an overpressure scenario. We have the capability of performing tube vibration analyses and transient pressure surge analyses as part of a tube rupture scenario evaluation.
- Application of paragraph UG-140 (formerly Code Case 2211) of ASME Section VIII, Division 1. This permits, under certain circumstances, the use of system design and/or instrumentation safeguards for overpressure protection in lieu of a pressure relief device
- Assessment of criteria and required conditions for the use of isolation valves in the pressure relief path
- Dispersion analysis of atmospheric discharges
- Flare system design reviews involving overpressure scenario assessments and possible simultaneous discharges of multiple relief devices; we can also assess the credibility of any flare load reduction credits (e.g. dynamic modeling, HIPS, favorable instrument response)
- Flare radiation studies
R-Stamp Certification
At times, a vessel re-rate may be an economical option to rectify pressure relief system inadequacies by enabling the use of a higher relieving pressure. E2G is certified by the National Board R-Stamp program to perform pressure vessel re-rating calculations.
