{"id":16800,"date":"2026-07-21T21:40:12","date_gmt":"2026-07-21T13:40:12","guid":{"rendered":"https:\/\/aobosteel.com\/?p=16800"},"modified":"2026-07-23T20:51:05","modified_gmt":"2026-07-23T12:51:05","slug":"d2-tool-steel-sendzimir-cluster-mill-rolls","status":"publish","type":"post","link":"https:\/\/aobosteel.com\/ko\/blog\/d2-tool-steel-sendzimir-cluster-mill-rolls\/","title":{"rendered":"Sendzimir \ud074\ub7ec\uc2a4\ud130 \ubc00 \uc791\uc5c5\uc6a9 \ub864\uc5d0 D2\uac00 \ud45c\uc900\uc73c\ub85c \uc120\ud0dd\ub418\ub294 \uc774\uc720\ub294 \ubb34\uc5c7\uc77c\uae4c\uc694?"},"content":{"rendered":"

Why AISI D2 Tool Steel Is the Standard Choice for Sendzimir Cluster Mill Work Rolls<\/h1>\n\n\n\n

Cold rolling mills that use a Sendzimir configuration, commonly called 20-High or Z-Hi cluster mills, are built around one core design decision: the work rolls are made deliberately small in diameter. A smaller work roll lowers the rolling force needed to reduce the strip, cuts power consumption, and reduces the amount of lateral spreading in the material as it passes through the stand. This is what makes cluster mills so effective for rolling thin, hard, or high-strength strip and sheet.<\/p>\n\n\n\n

The tradeoff is mechanical. A slender roll under heavy load wants to bend. Left unsupported, that deflection would ruin gauge control and eventually crack the roll itself. Cluster mill designs solve this by nesting the work roll inside a full stack of intermediate rolls, which in turn transfer the rolling load outward to large backup rolls and a rigid housing. The work roll never has to resist bending on its own. It only has to survive compression, wear, and surface contact.<\/p>\n\n\n\n

That single design fact changes what “the right steel” means for this application, and it is why AISI D2<\/a> has remained the standard material for both work rolls and intermediate rolls in these stands for decades.<\/p>\n\n\n\n

Both 20-Hi and Z-Hi mills share this same roll cluster and force path. The only structural difference is at the work roll itself: Z-Hi work rolls can be withdrawn sideways for a fast roll change, without dismantling the stand.<\/p>\n\n\n\n

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Z-Hi Cold Rolling Mill \u00b7 Side-Withdrawal Type<\/h3>\n

Same cluster as 20-Hi; work rolls withdraw sideways for fast change<\/p>\n\n\nZ-Hi Cold Rolling Mill \u2014 Working State with Fast Roll Change<\/title>\nCross-section animation of a Z-Hi cold rolling mill. Same roll cluster as 20-Hi, but work rolls can be withdrawn sideways for fast roll change. Animation shows upper work roll sliding out and returning. Rotation directions follow kinematics: same-layer rolls rotate the same direction, adjacent layers rotate in opposite directions.<\/desc>\n\n\n\n<\/marker>\n\n\n<\/marker>\n