Evaluation of Spring Operated Pressure Relief Valve Maintenance Intervals and Extension of Maintenance Times Using a Weibull Analysis with Modified Bayesian Updating | AIChE

Evaluation of Spring Operated Pressure Relief Valve Maintenance Intervals and Extension of Maintenance Times Using a Weibull Analysis with Modified Bayesian Updating

Type

Conference Presentation

Conference Type

AIChE Spring Meeting and Global Congress on Process Safety

Presentation Date

March 14, 2011

Duration

30 minutes

Skill Level

Intermediate

PDHs

0.50

The Savannah River Site (SRS) spring operated pressure relief valve (SORV) maintenance intervals were evaluated using an approach provided by the American Petroleum Institute (API RP 581) for risk-based inspection technology (RBI). In addition, the impact of extending the inspection schedule was evaluated using Monte Carlo Simulation (MCS). The API RP 581 approach is characterized as a Weibull analysis with modified Bayesian updating provided by SRS SORV proof testing experience.

Initial Weibull parameter estimates were updated as per SRS's historical proof test records contained in the Center for Chemical Process Safety (CCPS) Process Equipment Reliability Database (PERD). The API RP 581 methodology was used to estimate the SORV's probability of failing on demand (PFD), and the annual expected risk.

The API RP 581 methodology indicates that the current SRS maintenance plan is conservative. Cost savings may be attained in certain mild service applications that present low PFD and overall risk. Current practices are reviewed and recommendations are made for extending inspection intervals. The paper gives an illustration of the inspection costs versus the associated risks by using API RP 581 Risk Based Inspection (RBI) Technology. A cost effective maintenance frequency balancing both financial risk and inspection cost is demonstrated.

Presenter(s) 

Once the content has been viewed and you have attested to it, you will be able to download and print a certificate for PDH credits. If you have already viewed this content, please click here to login.

Language 

Checkout

Checkout

Do you already own this?

Pricing

Individuals

AIChE Member Credits 0.5
AIChE Pro Members $15.00
AIChE Graduate Student Members Free
AIChE Undergraduate Student Members Free
AIChE Explorer Members $25.00
Non-Members $25.00