Reason analysis of welded joints cracking in membrane wall elements as a basis for manufacturing technology selection of the evaporator collector with new generation low-alloy bainitic steel for boilers with supercritical working parameters

• Autorzy: Dobrzański J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The aim of the study was to evaluate crack sensibility of low-alloy bainitic steel 7CrWVNb9-6 ( P23 ) and 7CrMoVTiB10-10 (P24) after welding on the basis of the results of welded gas-tight tubular wall elements and to propose changes in the manufacturing technology of the evaporator collector with supercritical working parameters of that steel group. Design/methodology/approach: On the basis of out carried macroscopic, microscopic researches in SEM using EBSD technique and material hardness measurements of circumferential and fillet welded joints the places of occurrence and the character of occurring cracks have been determined. Findings: The influence of flat bars forms, welding parameters, the nature of joint penetration on crack sensibility in circumferential and fillet welded joints of membrane walls of the evaporator collector made of new generation low-alloy bainitic steels for power engineering intended for use in boilers with supercritical working parameters. Practical implications: Obtained results and out carried reason analysis of cracking of welded joints of membrane walls made of new generation low-alloy bainitic steels for power engineering allowed to propose three ways of conduct as far as changes and selection of manufacturing technologies of evaporator collector reducing or eliminating crack sensibility of welded joints. Originality/value: The applied methodology, adopted procedure and proposed changes in the manufacturing of membrane walls, installation and repair of the evaporator collector with supercritical parameters made of new generation low-alloy bainitic steels for power engineering will be used by manufacturers in modifying and developing new applied technologies of manufacturing those elements.

Słowa kluczowe

EN

Steel 7CrWVNb9-6 ( P23 ); Steel 7CrMoVTiB10-10 (P24); welding

PL

stal 7CrWVNb9-6 (P23); spawalnictwo

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2013
• Tom: Vol. 64, nr 1
• Strony: 5--14
• Opis fizyczny: Bibliogr. 32 poz.

Twórcy

autor

Dobrzański J.

• Institute for Ferrous Metallurgy, ul. K. Miarki 12, 44-100 Gliwice, Poland

Bibliografia

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