Biuletyn Instytutu Spawalnictwa No. 01/2012

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deformities, as they considerably distorted the primary reception of the sign. Afterwards, all the fragments were to be joined to form a whole sign again. Straightening and joining have an enormous effect on the legibility of the primary functions and meaning of the sign; therefore, the activities had to be preceded by a very thorough investigation. The fundamental assumption of the conservation was to protect all the components of the sign – pipes, letters, welds, and preserve the original paint coatings. At first, the conservators thoroughly documented the condition of the sign. In doing so they used visible light as well as ultraviolet and infrared photography. The sign was scanned in three dimensions. The tests also involved analysis of the chemical composition and hardness measurements of the material out of which the individual elements of the sign were made. Thanks to endoscopy and magnetic particle inspection it was possible to identify the slightest metal damage, invisible to the naked eye. Separate tests were carried out in relation to the protective coatings. All of these activities allowed the development of a programme of conservation [2]. According to the assumptions of the conservation programme, the connections of all the elements of the sign should be stable, durable, possibly invisible, and have no detrimental effect on the appearance of the sign. It was decided that the method employed to join Sign pipe 24 BIULETYN INSTYTUTU SPAWALNICTWA the elements should be the same as that applied originally, i.e. welding. Such a method should ensure a relatively narrow heat affected zone, minimum porosity, and complete penetration of the pipe joints (due to changing loads of the sign put up on the gate). Other requirements included entirely crack-free joints and as little difference in the colour of the welds and the parent metal of the elements made of carbon steel. The Conservation Section of the Auschwitz -Birkenau State Museum turned to Instytut <strong>Spawalnictwa</strong> with a request to conduct these works aimed at selecting a technology of repair welding the sign elements; the technology was to meet requirements formulated by the Conservation Section. The request also required technological supervision over the repair welding of the sign elements [5, 6]. The process and results of the conservation are presented below. Parent metal of sign elements The upper and lower seamed pipes of the historic sign are made of carbon steel having the chemical composition as presented in Table 1. Carbon steel used in the production of the sign pipes is characterised by good metallur- Table 1. Results of chemical analysis of pipe material [1] and carbon equivalent Contents of chemical elements [%] C Si Mn Cr V Ni Cu Carbon equivalent Ce [%] upper 0.0585 0.0065 0.3255 0.006 0.002 0.008 0.0228 0.12 lower 0.0956 0.0065 0.4606 0.006 0.002 0.008 0.0203 0.18 Lower pipe – Al content: 0.025%; P content: 0.0218%; S content: 0.0468%. Upper pipe – Al content: 0.025%; P content: 0.0268%; S content: 0.0661%. Carbon equivalent: C Mn Cr + Mo + V Ni + Cu = C + + + ,% 6 5 15 Table 2. Results of chemical analysis of material of pipes technological welding tests [5] Test Contents of chemical elements [%] pipe C Si Mn Cr Mo V Ni Cu Ce [%] upper 0.065
gical weldability, confirmed by the chemical composition and related carbon equivalent. For this reason, welding of the steel does not require any special precautions aimed at preventing the formation of hardened structure in the heat affected zone. On the basis of a low silicon content (Si
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Page 3 and 4: Summaries of the articles J. Dworak
Page 5 and 6: Jerzy Dworak Research Impact of las
Page 7 and 8: cess being carried out at a specifi
Page 9 and 10: pulses up to several dozen millisec
Page 11 and 12: ectangular pulse, P i max =702 W, p
Page 13 and 14: ectangular pulse, P i max =1752 W s
Page 15 and 16: Antoni Sawicki Modified Habedank an
Page 17 and 18: 1 dr r dt - in the resistance form
Page 19 and 20: The conditions of the selection of
Page 21 and 22: Similarly as previously (37), one c
Page 23: Eugeniusz Turyk, Agnieszka Żydzik-
Page 27 and 28: Damage was also caused to the welde
Page 29 and 30: Initial selection of method for wel
Page 31 and 32: Fig. 19. Assembly table with fixed
Page 33 and 34: Agnieszka Kiszka, Tomasz Pfeifer Va
Page 35 and 36: Fig. 4. Course of changes in curren
Page 37 and 38: extreme, the process was less stabl
Page 39 and 40: Fig. 13. Macrostructure of T-shaped
Page 41 and 42: L=1 mm, I=25 A L=1 mm, I=50 A L=1 m
Page 43 and 44: case of TIG welding (for similar we
Page 45 and 46: Other, equally important research i
Page 47 and 48: tion of a function connected with t
Page 49 and 50: The intensity of arc radiation was
Page 51 and 52: On the basis of calculations (Table
Page 53 and 54: NR 01/2012 BIULETYN INSTYTUTU SPAWA
Page 55: INSTYTUT SPAWALNICTWA The Polish We

Biuletyn Instytutu Spawalnictwa No. 01/2012

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