Effects of Steel Cast GS30Mn5 Hardening Parameters on Dredger`s Sheave Edge Properties

Dredger� are �pe�ial �ea fl�ati�g ve��el� u�ed ��r rem�vi�g �ea b�tt�m material i� �rder t�: re�hape harb�r u�derwater area� a�d waterway�, a��embli�g pipeli�e�, prepari�g �a�d bea�he� a�d ��a�t� t� ha�dle with er��i�� impa�t, �il re��ur�e� expl�itati��, ��rmi�g ma�-made i�la�d�... Thi� paper i� ba�ed �� �ele�ti�� �� heat treatme�t parameter� �� �heave�, �ur�a�e err�r� determi�ati�� meth�d a�d �ur�a�e damage� re��very. Om te�t �ample� made �ut �� �ame material (��30M��) built—up weldi�g te�t wa� �arried �ut �� (�MAW pr��edure) by fluti�g prepared damage area. Next �tep wa� i�du�ti�� harde�i�g u�i�g vari�u� parameter�. Determi�ati�� �� �ra�k� appeara��e wa� d��e by mag�et meth�d. By re��rdi�g �r��� �e�ti�� �tru�ture a� well a� hard�e�� mea�uri�g it ha� bee� determi�ed that be�ide� �ertai� level �� e�ergy i�put (ele�tri�al �urre�t �reque��y) �ur�a�e layer pr�pertie� �� �heave edge depe�d al�� ab�ut �h���i�g pr�per ���li�g medium. �ati��yi�g hard�e�� value� (320÷400 HB) were a�hieved ��mbi�i�g air a�d water ���li�g �imulta�e�u�ly with av�idi�g �ra�k� appeara��e. Parameter� �ele�ted that way �h�uld e��ure l��g w�rki�g peri�d �� r�pe� (hard�e�� �00÷��0 HB) a� well a� �a�e dredger� per��rma��e.