Perforating Pressure Transients & Gun Shock Loads: Prediction, Validation, & Mitigation

Transcription

1 Perforating Pressure Transients & Gun Shock Loads: Prediction, Validation, & Mitigation Brenden Grove, Carlos Baumann, Andy Martin, Charlie Stulb, Juan Pablo Guerra European and West Africa Perforating Symposium; presentation # November 2012

2 Perforating Pressure Transients and Gun Shock Loads: Prediction, Validation, and Mitigation Problem Description Model Overview Model Application & Validation: Tubing Conveyed Perforating Examples Wireline Perforating Examples Mitigation of Gun Shock Phenomena

3 Perforation Time Scales

4 Model Overview (1/2) Gun system acts as a pressure source/sink generating pressure waves in the wellbore Pressure waves acting on cross-sectional area changes produce gun shock loads Model predicts interactions among gun, wellbore, and reservoir

5 Model Overview (2/2) Prediction of transient pressure around guns and sandface for perforation clean up (DUB) Prediction of gun movement, tubing and packer loads, cable tension and weak point load Gun shock is typically an issue in very high pressure wells or with large OD guns Typically not an issue for most perforating jobs Software verified using our extensive database of perforating jobs (thousands)

6 Snapshot Gun Shock Model Application & Validation Model predicts wellbore pressure transients, gun shock phenomena Extensive application to field job design, risk reduction Validation with field & laboratory gage data

7 Example Minimizing Gun Shock Loading SPE

8 Example Minimizing Gun Shock Loading SPE TCP job with 7.0-in guns and Automatic Gun Release

9 Initial Gun Loading Optimized Gun-Loading to Minimize Gunshock Loads

10 Initial vs. Optimized Gun-Loading to Minimize Gunshock Loads

11 Initial vs. Optimized Gun-Loading to Minimize Gunshock Loads

12 Initial vs. Optimized Gun-Loading to Minimize Gunshock Loads Peak load on the Auto. Gun Release system: -58 klbf vs. -1 klbf Peak up-hole force on the packer: -47 klbf vs. -3 klbf Peak down-hole force on the packer: 155 klbf vs. 75 klbf Conclusion: Software optimization is crucial to prevent gunshock damage and non-productive time / $ loss

13 Model Validation HP guns with dual fast gauges SPE Net perforation interval 200 ft 29-gram HMX big-hole charges at 20 spf Top of safety spacer to packer 360 ft Bull-nose to sump packer 10 ft Bull-nose to PBTD 267 ft Initial wellbore pressure at depth 19,320 psi 14.8 ppg brine

14 Tubing axial load and total packer load up to 1.2 seconds

15 Model Validation HP guns with dual fast gauges SPE Gunstring with Two Fast-Gauges - Actual Run vs. Simulated

16 Example WL Weak Point Load IPTC 14300

17 Example WL Weak Point Load IPTC 14300

18 Example WL Weak Point Load IPTC 14300

19 Gun Shock Study in HP Wells SPE

20 Gun Shock Study in HP Wells SPE Some tubing damage on one well. If simulation run before the job, helical buckling would have been predicted.

21 Gun Shock Study in HP Wells SPE Recovered crushable elements from explosive activated shock absorbers are evidence of loads. Model can be used to predict shock loading with or without shock absorbers.

22 Gun Shock Study in HP Wells SPE Model predictions match very well with gage measurements 17 jobs

23 Gun Shock Solution in HP Well Modeling pre-job design Mitigation Perforating Shock and Debris Reduction Technology Validation model predictions confirmed with gage measurements

24 Summary Gun Shock Model Application & Validation Model reliably predicts Perforating wellbore dynamics Dynamic forces on completions Dynamic loads on WL weakpoint Gun movement Model extensively validated with field data Solutions to reduce gun shock can be modeled Solutions implemented in the field, gun shock problems successfully eliminated

25 Perforating Pressure Transients and Gun Shock Loads: Prediction, Validation, and Mitigation Problem Description Model Overview Model Application & Validation: Tubing Conveyed Perforating Examples Wireline Perforating Examples Thank you Mitigation of Gun Shock Phenomena