TASK GROUPS

TASK AREAS

This goal is achieved by regular meetings of EPERC Task Groups, composed by experts who are EPERC members or work for EPERC member companies. Each Task Group is working on a specific subject which is of common interest of the members.

 

EPERC areas of research priorities already defined by its Members are:

  1. Fatigue
  2. Alternatives to Hydro Testing For In-Service Pressure Equipment
  3. Rules for bolted flange connections
  4. Non-linear analysis
  5. Additive Manufacturing (new)

7. Fitness for Service

12. Re-certification of existing P.E.

Proposed new TG: TG6 Creep

Click here to see the general presentation of all the TG meetings.

Look at each TG page to see the call for experts and the program of the next TG meeting.

Do not forget that EPERC can promote the constitution of joint ventures among EPERC Members in order to prepare specific Research projects that may be financed by the European Commission. This happened many times in the past (Design by Analysis, ENVELOPS, PERL, Comparative Study)

 

TG 1: FATIGUE

Next meeting of TG1 has been scheduled for September 22 nd 2021. Click here to Register and Download the Agenda.

Click here to view the Meeting Report of January 22nd, 2021.

Click here to view the Meeting Report of January 28th, 2020.

The ongoing work on the revision of the clauses in EN 13445-3 dedicated to fatigue (principally clauses 17 and 18) within CEN/TC 54/WG 53/DESIGN CRITERIA revealed open items in the fatigue assessment procedure of unwelded and welded parts that cannot be resolved up to now by the existing working group. These open items are addressed in the Technical Note CEN/TC 54/WG 53 N 829. Some of these open items had already been identified during the first revision of the fatigue clauses in the 1990s and have been addressed in the background document “EN 13445 ‘Unfired pressure vessels’. Background to the rules in Part 3 Design”. These open items are in particular

  • Mean data fatigue curves for unwelded parts (origin of data, possibly unsafe, strong dependence on ultimate tensile strength).
  • Design fatigue curves for unwelded parts (safety/margin factors, correction factors, related probabilities of survival).
  • Extrapolation of the component design fatigue curves for welded parts taken from EC3/IIW recommendations into the low cycle fatigue (LCF) range where the available data base is still very scarce. Furthermore, the question of load-controlled or strain controlled testing in this context needs to be resolved.
  • Influence of environment on fatigue behavior is mentioned but there is no quantification of this effect on crack initiation or crack propagation.

Click here to view the program of work of this TG (all EPERC members wishing to participate shall contact the TG Chairman Mr. Guy Baylac at guy.baylac114@gmail.com)

Members can download other meeting documents in the Restricted Area

 

TG 2: ALTERNATIVES TO HYDRO TESTING FOR IN-SERVICE PRESSURE EQUIPMENT

Please click here to access the In-Service Pressure Equipment National Approach Survey presented at the GA 2019.

Please click here to read the report of the TG2 meetings of Milano, January 28th.

In the restricted area EPERC members can download the following presentation:

TG2 -Presentation Crescenzo Di Fratta

Click here to view the program of work of this TG (all EPERC members wishing to participate shall contact the TG Chairman Mr. Crescenzo di Fratta at c.difratta@tuvaustriaitalia.com)

TG 3: BOLTED FLANGE LEAK TIGHTNESS

The leak tightness of Bolted Flange Connections is becoming a real problem for the designers, because every year the European legislation on air pollution is becoming more and more severe. Up to now, the European Standard EN 1591.1:2013 is the only standard which permits the design of bolted flange connections taking into account a specified leak rate: however generally agreed gasket parameters are missing, therefore the use of the standard is only possible under consideration of the gasket suppliers’ proprietary data, or considering the results of specific testing to be carried out on the gaskets.

 

Moreover, as all the new modern methods for the design of bolted flange joints, the design according to EN 1591.1:2013 is based on specified bolt loads, applied with proper tightening devices which assure the control of the load considering also the relevant (+ or -) tolerances. This approach is not very popular with the users, because it will greatly decrease their freedom, in presence of leaking joints, to tighten the bolts as much as possible in order to stop the leak.

Under the “Technical documents” you can download the paper of F. Lidonnici “Design of Bolted Flange Connections – Status of EN Standards”.

Please click here to read the report of the TG3 meeting of Milano, January 29th.

In the restricted area EPERC members can download the following presentations:

TG3-Presentation_Hubert_Lejeune of the TG Chairman Mr. H. Lejeune

DESTEC_Flanges

Click here to view the program of work of this TG.

 

TG 4: NON-LINEAR ANALYSIS

Scope and Objectives of TG4

 

After a detailed existing Codes and Standards comparison [1], it was concluded that many Pressure Equipment Code have a Chapter on Nonlinear Analysis with limited information to perform the analyses and limited validation documents of their proposals. 2 particular Codes has been considered with particular attention: ASME BPV Code – Section VIII – Division 2 and AFCEN – RCC-MRx Code. Since this review a new Appendix has been proposed in AFCEN RCC-M Appendix ZC.

The major objectives of this Group are to review all the nonlinear rules used to design Pressure Equipment in different international Codes and the R&D State of the Art in order to propose:

  • a “recommended practice document” based on existing knowledge
  • a “complementary experimental R&D program“, developed with the support of EPERC and the European Commission, with a regular update if necessary of the previous document,
  • a “set of benchmarks” to assure usability of the proposed rules and that can be used as a set of typical applications

The “recommended practice document” will contain the different rules applicable, their detailed application, the material data required, the basic criteria, the Quality management required and all the associated validation (theoretical, engineering approaches and experimental validation).

Major failure modes and degradation mechanisms of Pressure Equipment will be considered:

 

  • Under monotonic loads: plastic collapse, plastic instability, local failure, buckling
  • Under cyclic loads: fatigue, shakedown
  • Consequences of potential crack in a pressure equipment: failure assessment diagram and reference stress approach, local approaches of rupture and “Master Curve Approach”, leak before break…
  • Particular cases of specific nonlinear analyses: openings and reinforced nozzle, elastic follow-up in piping system, seismic design, bolted flanges, bellows…

 

Creep conditions will not be considered in this first phase of this Project.

 

Click here to view the document “Non linear design rules”.

Click here to read the report of the TG4 meeting of Milano, January 29th.

Click here to view the program of work of this TG (The next meeting of TG4 will take place on September 2nd, 2021)

Click here to download the Agenda of the Telematic Meeting of September 2nd, 2021

Click here to read the report of the TG4 Telematic Meeting of September 2nd, 2021

For further details please contact the TG Chairman Mr. Claude Faidy at info@eperc-aisbl.eu)

 

TG 5: ADDITIVE MANUFACTURING

 

Please click here to read the report of the TG5 meeting of Milano, January 28th.

TG 7: FITNESS FOR SERVICE

 

Click here to download the Agenda of the 1st Meeting

Click here to view the Meeting Report of June 3rd, 2021

Click here to download the Agenda of the 2nd Telematic Meeting

Click here to view the Meeting Report of September, 1st 2021.

For further details please contact the TG Chairman Mr. Claude Faidy at info@eperc-aisbl.eu

 

TG12: Re-certification of existing P.E.

Click here to view the Program of Work of this TG – (all EPERC members wishing to participate shall contact the TG Chairman Mr. Andrea Tonti at a.tonti@inail.it)

Please click here to read the Report of the First TG12 meeting of Milano, January 28-29th 2020.

In the restricted area EPERC members can download the following presentations:

TG12- Minutes PE Recertification – January, 25th 2021 – by Andrea Tonti

Blue Guide Application Required by Dutch Law

______________________________________________________________________________________________________________________________________________

QUESTIONNAIRE for determination of Recertification procedures:

click here for English Questionnaire

click here for French Questionnaire

click here for German Questionnaire

click here for Italian Questionnaire

Members can download other meeting documents in the Restricted Area

 

PROPOSED TECHNICAL TASK GROUPS