2015 International Perforating Symposium – Europe IPS also SPE MS Thermal Decomposition Effects on Perforating Performance and Safety A.E. Boock, M.S. Brinsden, Shell C. Sokolove, T.G. Golian, Hunting Titan J.L. Maienschein, E.A. Glascoe, Lawrence Livermore National Laboratory Amsterdam 20 th May 2015

AFFECTED PERFORATING SYSTEM COMPONENTS Slide 2 Perforating Gun Detonating Cord Shaped Charge Arming Sub Detonator – Det Cord Connection Perforating Gun To Top/Well Head Bottom/Toe IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

SETTING THE STAGE… Slide C downhole temperature Normal HMX operations Contingency included severe weather downtime IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

ECONOMIC IMPACT Slide 4 PROSPER SPOT IPR/VLP simulation results for HMX and HNS charges Based on time temperature plot provided by manufacturer, HNS was selected over HMX Result: 30-40% reduction in penetration and an estimated 20% reduction in well performance 180 bbl/day 298 bbl/day HMX HNS IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

SAFETY Thermal runaway occurs when heat from thermal decomposition builds within the explosive faster than it dissipates Once thermal runaway has started, it is often impossible to quench the reaction and prevent an explosion, even if the heat source is removed The critical temperature at which explosion will occur as well as the time to explosion can be calculated by using:  Explosive Properties  Charge Geometry  Exposure Temperature  Exposure Time Slide 5 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

SAFETY Slide 6 Consequence Increasing Time and Temperature Exposure IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

LIMITATIONS OF EXISTING CURVES  Data used to create the industry curves did not identify the explosive type, purity, particle size, binder, pressed density, confinement of the explosive  All of these parameters affect thermal stability  Assumption is that the data originated from results published by national labs  Testing set up and equipment was not specified  The data was extrapolated  Consequences of exceeding the limits are unclear for end users Slide 7 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

THERMAL DECOMPOSITION Slide 8 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT METHODS FOR ASSESSMENT - COMPARISON Slide 9 15 min 2 hr 45 min 27 hr 45 min 11.5 days (280 hrs) 1.7 min 1 sec 6 hr Extrapolated Tested IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

Slide 10 CURRENT METHODS FOR ASSESSMENT Aside from full scale testing, there are three main lab-scale tests used to assess thermal stability:  Vacuum thermal stability (VTS) test  Ampoule test  One Dimensional Time to eXplosion (ODTX) -They measure different phenomena/conditions and their results are not directly interchangeable -They are all safety-derived tests -Major short coming is that the tests don’t reflect the way the explosives are configured in the perforating system because of the free volume in the test set up Advantage: lab-scale tests can be executed efficiently and affordably Disadvantage: some tests are so different from the end application that a direct application of the results could result in inaccurate and unsafe guidelines. IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT METHODS FOR ASSESSMENT - VTS Vacuum thermal stability (VTS) test:  Has a long history as a thermal stability test for explosives and propellants  The test involves heating a small amount of powder in an evacuated container for many hours  The pressure change is measured and outgassing volume is reported  The underlying assumption is that the outgassing results from decomposition of the explosive  Experimental parameters (mass, temperature, duration) vary significantly among practitioners Slide 11 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT METHODS FOR ASSESSMENT - VTS Chemical Reactivity Test  Related to VTS  Developed at Lawrence Livermore National Laboratory  The quantity and composition of the evolved gases is measured, providing direct measurement of explosive decomposition  Tests are conducted in steel apparatus, thereby avoiding safety problems with pressurized glass  This type of test is best suited as an accelerated aging test to provide experimentalist confidence in the stability of their materials at or near room temperature  The conditions used in these tests are milder than many wells and it may be difficult or impossible to extrapolate results from a 100°C-120°C experiment to higher temperatures Slide 12 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT METHODS FOR ASSESSMENT - AMPOULE Kneisl recently published a new stability test called the Ampoule Test The test, which is similar to the vacuum thermal stability test, involves heating 1 g of explosive powder in a 10 cm 3 glass vial for 2 to 2000 hrs. up to 350°C The outgassing is measured post-experiment; the experiment can measure up to 300 cm 3 /g, which is significantly higher than the outgassing from other versions of the VTS test Slide 13 This test still measures outgassing from a powder in a vessel with a relatively large amount of headspace IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT METHODS FOR ASSESSMENT - AMPOULE The same experiment performed on a high-density pressed part in a vessel with little or no headspace might produce thermal runaway response at lower temperatures or shorter timeframes This test could be used to develop kinetic models for degradation and outgassing which would be useful in predicting the pressurization as a function of time and temperature  Such a kinetic model would not reliably predict thermal runaway or thermal explosion of a material Slide 14 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT METHODS FOR ASSESSMENT - ODTX One Dimensional Time to eXplosion (ODTX) test  Designed by Lawrence Livermore National Laboratory  In this test, a ½ inch diameter sphere of explosive is heated with an isothermal boundary condition until it explodes  Time to explosion as a function of the boundary temperature is the resulting data  The apparatus consists of two aluminum blocks that each have a ½ inch diameter hemisphere machined out to accommodate the explosive sphere  The anvils are preheated and time-zero is defined as the time when the explosive is inserted between the anvils Slide 15  There is no headspace and the anvils are held together with a 15,000 psi load cell which prevents the reaction from quenching early due to gas venting IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT METHODS FOR ASSESSMENT - ODTX The test can include a pressure measurement during heating The results of this test cannot be used to directly predict the response of a large explosive charge because of scalability issues This test is used to help parameterize or validate a thermal-chemical explosion model For shaped charges, the thickness of the explosive (approximately ½ inch between the liner and the case) is close to the diameter of the ODTX sphere; consequently it is reasonable to use the results of this test, with simple adjustments to account for the difference in heat transfer through a sphere or a flat slab. Slide 16 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

CURRENT INDUSTRY GUIDENCE Industry Guidance:  API RP 67 Recommended Practice for Oilfield Safety  API RP 19B Recommended Practices for Evaluation of Well Perforators  Manufacturer supplied time-temperature curves Neither API RP adequately addresses thermal stability to the extent desired by explosive users within the industry API RP 19B Section 3 testing does not adequately assess time and performance!  Tests are performed under the same test conditions (i.e. no variation in time or temperature). Slide 17 IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

OPPORTUNITIES FOR IMPROVEMENT The key areas that need to be addressed with respect to thermal stability: Slide 18 Thermal Stability Potential for thermal runaway Pressure build- up as a result of thermal decomposition Safe handling for overexposed explosives Performance losses from degradation due to thermal decomposition IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

Slide 19 CONCLUSIONS Preliminary tests evaluate perforating systems against existing time temperature curves as a baseline for the current accuracy of the curves ODTX experiments conducted to determine the explosive properties (i.e. particle size, binders, purity, etc.) which most significantly influence thermal stability Expand testing with full scale perforating systems to evaluate holistic performance Test results used to develop models which will be validated against full scale perforating system experiments to determine the accuracy of the predicted outcomes Update API RP67 with safe handling guidelines and API RP 19B Section 3 with an improved test methodology capable of feeding data into the modeling tool IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

FORWARD PLAN Slide 20 Immediate Explosive components testing to assess accuracy of existing curves and the critical components (i.e. shaped charge, booster, det cord, etc.) Medium Term Progressing lab testing work with Lawrence Livermore National Lab with API support Longer time duration ODTX tests with explosive material from industry relevant blends Long Term Scalable model relevant to assessing performance and safety for industry appropriate explosives Additional explosive material, individual components, and full system testing IPS Thermal Decomposition Effects of Perforating and Safety Mark Brinsden

Acknowledgements / Thank You / Questions Many thanks to Shell, Hunting Titan, and LLNL for support of this work. Slide 21