Failure analysis of rolls with grooves

Abstract

The failure analysis of the rolls with grooves on the 3-high-roughing mill stand for hot rolling is presented. Detailed analysis of all the elements which influenced the failure was carried out, namely: the position and the place of all failures are determined and all fracture surfaces are described; the rolling forces are determined by analytical and experimental methods; numerical analysis of the local stresses due to rolling forces is performed with finite element method; stress time history of the individual local stress and stress spectrum are obtained from service loads; properties of the roll material (strength, hardness, toughness and ductility) is determined by experimental testing. Based on the results of investigation, main causes of failures are presented.

Failure analysis of rolling mill stand coupling

“…The experimen tally determined rolling forces were used for the calculation of the drive shaft torque, Ref. [1] and [5]. The torque of the middle drive shaft change according to time, Fig.13, is constructed from the rolling process on the roughing mill, Fig.12 and the torque of the middle drive shaft for each pass, Table 1.…”

“…The failures of the rolls with grooves on the 1 st stand of the 3-high-roughing mill stand occurred four times, Ref. [1]. The failures of the slipper coupling between the gearbox and the roughing mill occurred 2 times, Fig.2.…”

Influence of roll neck design and inlet rolling temperature on roll neck service life

“…For rolling mill rolls, flat or with grooves, the shoulder between roll necks is the most critical area on the rotational-bending fatigue due to stress concentration. For the rolls with grooves, the grooves can also be critical areas mostly depending on their shape [1]. Rolling force and rolling torque intensity depend on technological parameters.…”

The influence of rolling speed on the fatigue life of rolls with grooves

“…One of the ways to increase the rolling mill production is to increase the rotation speed of existing rolling mill stands which can affect the roll fatigue life (Luksˇa, 2013). In order to increase the rolling production and to avoid possible fatigue failure of the rolls (Domazet et al, 2007), an analysis of the rolling speed influence on fatigue life of the rolls has been carried out on three-highroughing mill stand in ''Steelworks Split''. Additional motivation for this study was the lack of adequate literature.…”