A. Shtertser* , О. Stoyanovskii, B. Zlobin, Yu. Meshcheryakov, Yu. Skornyakov

1. EPNM -2014 Cracow, Poland, May 25-30, 2014 Designing and manufacturing of explosion chambers for scientific research and explosive working of materials A. Shtertser*, О. Stoyanovskii, B. Zlobin, Yu. Meshcheryakov, Yu. Skornyakov Design & Technology Branch of Lavrentyev Institute of Hydrodynamics SB RAS Novosibirsk, Russia *asterzer@mail.ru

2. Localization of explosion factors Any explosion results in appearance of shock wave, seismic wave, toxic detonation products, and, sometimes, flying debris (explosion factors). There are different facilities for localization of explosion factors: natural caves in mountains, mines, structures made of reinforced concrete, and metal Explosion Chambers (ECh). Among ECh there are chambers designed for one explosion and chambers made for a great number of shots. First ones are purposed for transportation of explosive charges, say from the places where terrorists put them (railway stations, airports, city streets, etc.) to a special site for elimination. Such ECh can resist only one unauthorized explosion. Second ones are designed for multiple explosions and are used in research or in technological applications. There are good many companies and institutions in the world which can produce metal ECh. Different modifications of ECh were built in Russia, USA, Germany, China, South Korea, Ukraine , and other countries.

3. Publications on the subject Available in English: [1 ] W. E. B a k e r, The elastic-plastic response of thin spherical shells to internal blast loading, J. Appl. Mech. 27, 139-144 (1960). [2] W. E. B a k e r, P. A. C o x, J. J. K u l e s z, R. A. S r e h l o v, P. S. W e s t i n e, Explosion Hazards and Evaluations, Elsevier Science B.V. (1983). [3] V. P. M u k o i d, Transient dynamic behavior of a closen the subjectd gas-filled shell subjected to internal blast loading, International Applied Mechanics 35, 3, 288-294 (1999). [4] D a v i d K a r l s s o n, Validate Simulation Techniques of a Mobile Explosive Containment Vessel, Proceed. 5-th ANSA & µETA Intern. Conf., 5-7 June 2013, presentation 2A_2_karlsson, http://www.beta-cae.gr/conference05.htm#proceedings. [5] M a s a t a d a A r a k i, Multi-purpose explosion chamber with sound muffing and vibration cutting means, High-Pressure Research: an International Journal 5, 1-6, 906-908 (1990). [6] K i m W. K i n g, Explosion containment vessel, US patent No. 6644165 B1 dated 11.11.2003. [7] D a v i d C. A b b e, J o h n L. D o n o v a n, Portable explosion containment chamber, US patent No. 8621973 B2 dated 07.01.2014. [8] J o h n L. D o n o v a n, Method and apparatus for containing and suppressing explosive detonations, US patent No. 5884569 A dated 23.03.1999. [9] D a v i d C. A b b e, J o h n L. D o n o v a n, Portable explosion containment chamber, US patent No. 20120312147 A1 dated 13.12.2012.

4. Publications on the subject [10] A. F. D e m c h u k, Method for designing explosion chambers, Journal of Applied Mechanics and Technical Physics, 9, 5, 558-559 (1968). [11] V. V. A d i s h c h e v, V. M. K o r n e v, Calculations of the shells of explosion chambers, Combustion, Explosions, and Shock Waves, 15, 6, 780-784 (1979). [12] A. A. B u z u k o v, Forces produced by an explosion in an air-filled explosion chamber, Combustion, Explosion, and Shock Waves, 16, 5, 555-559 (1980). [13] S. A. Z h d a n, Dynamic load acting on the wall of explosion chamber,Combustion, Explosion, and Shock Waves, 17, 2, 241-244 (1981). [14] V. A. M a l’ t s e v, Yu. A. K o n o n, V. V. A d i s h c h e v, V. M. K o r n e v, Experimental study and analysis of the vibrations of an impulsively loaded thin-walled spherical shell, Combustion, Explosion, and Shock Waves, 20, 2, 214-218 (1984). [15] V. V. S i l’ v e s t r o v, A. V. P l a s t i n i n, N. N. G o r s h k o v, O. I. S t o y a n o v s k i i, Reaction of real explosion chamber to internal pulsed loading, Combustion, Explosion, and Shock Waves, 30, 2, 228-234 (1994). [16] A. A. P i k a r e v s k i i, O. I. S t o y a n o v s k i i, Effect of shielding of a part of the casing of a technological explosion chamber on its stress state, Journal of Applied Mechanics and Technical Physics, 54, 2, 337-342 (2013). [17] V. V. S I l’ v e s t r o v, A. V. P l a s t i n i n, N. N. G o r s h k o v. Effect of the media surrounding an explosive charge on explosion chamber shell reaction, Combustion, Explosion, and Shock Waves, 30, 2, 222-227 (1994)

5. Publications on the subject Available in Russian: [18] A.F. Demchuk, V.P. Isakov, Metal explosion chambers: monograph. – Publishing house of Krasnoyarsk State University (2006), in Russian. [19] U. P. M e s h e r i a k o v, A. A. P i k a r e v s k i i, O. I. S t o i a n o v s k i i, Calculation of maximum tension in poles of explosion chamber for explosion welding under conditions of real stressing, Izvestia VolgGTU (Reports of Volgograd State Technical University), issue 5(65), 56-62 (2010), in Russian. [20] V. A. Mal’tsev, Yu. A. K o n o n, L. B. P e r v u k h i n, G. V. S t e p a n o v, Opyt expluatatsii, rascheta i perspectivy sozdanija vzryvnykh kamer, in: I.V. Yakovlev, V.F. Nesterenko (ed), Proceed. of the 9-th Intern. Conf. on High Energy Rate Fabrication, August 18-22, 1986, Novosibirsk, Lavrentyev Institute of Hydrodynamics (1986), in Russian [21] V. V. D a n i l e n k o, Explosion: physics, engineering, technology, Мoscow: Energoatomizdat (2010), in Russian. [22] A. G. K a z a n t s e v, A. D. C h u d n o v s k i i, A. A. S i l a e v, L. B. P e r v u k h i n, P. A. N i k o l a e n k o, Stress state and strength of weld explosion-loaded vessels, Tjazholoe Mashinostroenie, issue 11, 26-29 (2010), in Russian. [23] A. G. K a z a n t s e v, A. D. C h u d n o v s k i i, S. S. S m o l i a n i n , L. B. P e r v u k h i n, P. A. N i k o l a e n k o, Stress and strain analysis and the durability of metal explosion-loaded vessels, Zavodskaya Laboratorija, 76, 12, 37-42 (2010), in Russian. [24] A. G. K a z a n t s e v, S. S. S m o l y a n i n o v, L. B. P e r v u k h i n, P. A. N i k o l a e n k o, D. R. K a p u s t i n, Stress and strain analysis of metal container with porous concrete protection under explosion-loading, Tjazholoe Mashinostroenie, issue 8, 27-32 (2011), in Russian.

6. Publications on the subject [25] A. A. S h t e r t s e r, Yu.P. M e s h c h e r y a k o v, A. F. C h e r e n d i n, O. I. S t o y a n o v s k i i, Explosion chambers – ecologically safe equipment,Nanotechnologii. Ekologia. Proizvodstvo (Nanotechnologies. Ecology. Production), issue 2, 90-91 (2010), in Russian. [26] Yu.V. S k o r n y a k o v, Yu. P. M e s h c h e r y a k o v. Definition of mass optimization of blasting chamber shells, Izvestia Samarskogo Nauchnogo Centra RAN (Reports of Samara Scientific Centre RAS),13, 4, 1110-1114 (2011), in Russian. [27]. S. K. G o d u n o v, Chislennoe reshenie mnogomernykh zadach gasovoi dinamiki, Moscow: Nauka (1976), in Russian. Internet Sites: [28] http://www.dynasafe.com (DYNASAFE Company) [29] http://www.npo-sm.ru/english/fontan.php (Special Materials Corporation) [30] http://www.ckp-rf.ru/usu/73564 (Moscow regional explosion center of shared use) The fundamentals for calculation of stresses arising in shells under explosive loading were developed by W. E. B a k e r [1]. in 1950-ies. Later on his book containing valuable information for researches and engineers working in the field of explosion physics was published [2].

7. Production of Explosive Chambers in LIH SB RAS Designing and manufacturing of metal explosive chambers (ECh) has begun in Lavrentyev Institute of Hydrodynamics SB RAS (LIH SB RAS) in 60-ties of the past century, just after its establishment. Originally EC were made for research work in the field of physics of explosion, and later on for industrial applications. The process of ECh designing was always closely associated with investigation of stresses arising in Ech shell under pulsed loading. The demand on industrial ECh has increased significantly in 70-ties Since 1976 and up to now, about 100 explosion chambers of various design and purpose have been manufactured; the explosive charge value varies within the range from 150 g to 16 kg ТNТ.

8. Features of Explosive Chambers The ECh designed in LIH SB RAS have a long service life (10 thousand shots and more); they completely isolate all explosion factors; can be mounted in laboratory rooms and industrial premises, and, as necessary, can be disassembled and transported to a new place of exploitation. Being combined with special purification devices, ECh enables to neutralize toxic components of explosion products.

9. Further topics • Equations for estimation of chamber mass and shell wall thickness for the composed shell; • 2) The line of developed and manufactured ECh.

10. Composed shell and its geometrical parameters R is the radius of the cylindrical part and spherical cover, H is the cylindrical part length, is the shell wall thickness. The explosive charge of mass М and specific explosion heat Q0 is situated in the shell center. The aim is to calculate the shell mass m and in condition of given allowable stress σm (cyclic strength of the shell material).

11. Formulas М is the mass of the explosive charge, kg; Q0 is the specific explosion heat, J/kg; µ is the Poisson’s coefficient, E is the Young’s modulus, ρ is the density, a0 is the sound velocity of the shell material. 2 is the axial stress in the cylindrical part of composed shell (it is equal to the meridional stress in the semi-spherical cover), and 1 is the circumferential stress in the cylindrical part of composed shell. m is the allowed equivalent stress (the parameter of material cyclic strength).

12. Modifications of Explosion Chambers and their applications A number of ECs have been developed for different technological applications and researching activities. Researching chambers are designed for relatively small explosive charges (150 – 200 g). They have special windows for optical shooting of fast processes and are usually employed for investigation of new explosives, explosive treatment of small samples, synthesis of new materials in small amounts, and etc. Industrial (technological) chambers are designed for bigger explosive charges (2 – 16 kg) and are purposed for production of bimetal parts, explosive hardening of metal articles, production of new materials by explosive synthesis, and so on. Industrial chambers also can be used in research works.

13. Research chambers with spherical and composed shells

14. Research chambers Explosive chambers KV-0,2 for 200 g TNT (weight 1,3 t, overall dimensions 1800 x 1200 x 1630 mm).

15. Explosion chamber KV-0.15 The researching chamber КV-0.15 designed for the explosive charge of maximum 0.15 kg. The external diameter of the cylindrical part of the shell and its height are equal to 0.75 m. The chamber has a charging hatch with the diameter of 0.36 m, 8 measurement inputs and two optical windows of 0.08 m in diameter. Inside the chamber, there is a working table, its diameter is 0.25 m. After each explosion, the chamber is blown with the compressed air (0.3 МPа), which is provided by two valves. The chamber mass is 800 kg. It is easy-serviceable and can be installed in rather small laboratory rooms.

16. Explosion chamber KIP-0.2 The KIP-0.2 chamber is intended for the nanodiamond synthes in small amounts for research purposes. It’s made of stainless steel. Chamber has charging hatch and attachment for product collection.

17. Explosion chamber DVK-0.2 It is the special research chamber made for Siberian Center of Synchrotron and TeraHerz Emission (Novosibirsk, Russia). It is designed for 0.2 kg of HE charge, the internal diameter of cylindrical part is 0.98 m, the diameter of two charging hutches is 0.5 m. There is a pneumatic opening / closing mechanism, chamber mass is 2.7 t. Synchrotron emission enables to get the unique information on the density distribution in detonation products behind the detonation wave front.

18. Industrial chamber KV-2M Explosion chamber of vertical type KV-2M is designed for maximal HE spherical charge mass of 2.0 kg, and flat charge mass of 1.7 kg TNT. The chamber weights 10.5 t. Inner diameter of the shell cylindrical part 1.3 m; work table diameter 0.7 m; inner height measured from the table to shell top 1.6 m. The chamber can be made with two or four optical windows. When windows has transparent inserts the maximal explosive charge mass is 0.5 kg. KV-2M chamber can be used for explosive working of materials and for destruction of ammunition, such as detonation fuses.

19. Industrial chamber KV-5 Another vertical-type chamber КV-5 is designed for 5 kg of HE and weights about 40t. It has overall plane sizes 4.6 х 2.8 m and height 3.4 m in the closed state and 4.3 m in the open state The working table of 1 m in diameter enables to treat quite large metal pieces or several articles together. Since 1991, more than 100 thousands bimetallic workpieces of plane bearings for diesel engines were manufactured . Chamber is installed in the Factory not far from Novosibirsk (Russia).

20. Explosion chamber KVG-8 The chamber of a horizontal type KVG-8 was designed for railway points explosive strengthening. For about 40 years this technology has been being utilized in Novosibirsk railway point factory. Since 1995 the chamber KVG-8 has been operating in Norilsk mechanical factory . In the chamber, bimetallic current leads to titanium electrodes are manufactured by the explosion method; these leads are used in electrolysis cells for nickel, titanium, and other metals production. The current lead presents a two-layer (copper / titanium) tube with the external diameter of about 50 mm and length up to 1.3 m. The chamber permits manufacturing 12 tubes at one explosion. The KVG-8 overall sizes with the pulled out work table are: the length is 16.4 m, width 2.5 m, height 2.2 m. The cylindrical shell is 5.7 m in length, its internal diameter is 1.6 m. The chamber mass (without ventilation system) is 48 t.

21. Explosion chamber KVG-16 The horizontal-type chamber KVG-16 presents the double (by length) chamber KVG-8. The chamber length in an open state is 27.2 m, its weight is 76 t. The chamber was utilized for elimination of special pyrotechnic charges. Within approximately two years, about 15 thousand explosions were organized in the chamber, with 16 kg of combustible mixture destroyed in each cycle.

22. Explosion chamber Alfa-2 There are other modifications of the EChs. For example, the chamber Alfa-2 for 2 kg of explosive charge was developed especially to produce the diamond-graphite mixture from carbon-containing explosive charges. These chambers are used for nano-size diamonds production (ultra-disperced diamonds). The chamber mass is 6.8 t, its overall plane sizes are 2.0 х 2.5 m, height 4.5 m, inner volume is 2 m3. The working cycle is 10 – 15 minutes, hence more than 60 kg of the explosive substance can be treated during one working shift.

23. Explosion chamber Alfa-2

24. Conclusion • Metal Explosion Chambers effectively isolate all explosion factors (shock wave, seismic action, flying fragments of experimental or technologies assemblies, detonation products). • Our many-years experience shows that Explosion Chambers can be successfully used in research work and in production purposes (explosion welding, explosion strengthening, new materials synthesis, ammunition elimination, etc.)

25. Thank you for your attention!