2019 №03 (01) DOI of Article
2019 №03 (03)

Automatic Welding 2019 #03
Avtomaticheskaya Svarka (Automatic Welding), #3, 2019, pp. 18-22

Effect of repeated heating in multi-pass submerged arc welding on resistance of welded joints of rotor steel to delayed fracture

V.Yu. Skulskyi1, S.I. Moravetskyi1, M.A. Nimko1, Yu.G. Pashchenko2, A.G. Kantor2, V.V. Dmytryk3

1E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
2JSC «Turboatom». 199 Moscow Ave., 61037, Kharkov, Ukraine. Е-mail: office@turboatom.com.ua
3NTU «Kharkov Polytechnic Institute». 2 Kirpicheva Str., 61002, Kharkov, Ukraine

On the example of the 0.25C-2CrNiMoV rotary steel joints, produced by submerged arc welding using the Implant method, the change in resistance to delayed fracture depending on the temperature of preheating and thermal effect during deposition of new beads was experimentally studied. The nature of change in hardness in the cross-section of quenching steel with surfacing was investigated, which illustrates the formation of quenching and tempering areas under the influence of repeated welding heating. Using critical stresses as a quantitative indicator, causing a delayed fracture, it was shown that after repeated welding heating, the resistance to cracking can increase by about 1.5...2.5 times or more. In the conditions of welding without preheating, repeated one-time and two-time cycles of welding heating increase the resistance to cracks up to the level obtained during welding with preheating up to 150...200 °C. 9 Ref., 4 Fig.
Key words: heat-resistant rotary steel, submerged arc welding, quenching, repeated welding heating, Implant, resistance to delayed fracture

Received: 28.11.2018
Published: 20.02.2019

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