Developing of roll drafting and computation drafting schedule of stock material gauge 350 mm on the block 950/900 "MMZ "Istil (Ukraine)"

Put in Ukraine GOST – 3-009-200 provide for output of round blank gauge 70-350 mm from carbon ordinary properties and quality, low-alloyed, alloyed and heat-resistant steel, and also tightened inspection nonmetallics.

By analysing of literature, was        educe, that no one block of the SNG don’t make in technological scale hollow billet gauge 350 mm. In connection with this was formed purpose of the work: to develop roll drafting and drafting schedule for production hollow billet gauge 350 mm.

Block 950/900 “MMZ “Istil (Ukraine)” was selected for production that billet.

Was proposed to use the pass sequence for       rolling round blank gauge 350 mm that include        preparative oval, pre- finishing oval and round pass. Special oval pass is performing a function of reparative and pre- finishing oval. It has irregular shape and promote ro      increase in stability of strip in pass.

In stand “900” (section a) is perceived to locate 3 finishing groove to roll stock material guage 350 mm for increase in efficiency of rolling process and mix broadening of products. In stand “950” (section b)   together with barrel is 2 Special ovals.

a)                                                             b)

Illustration. Roll drafting stand of the block 950/900 “MMZ Istis (Ukraine)”

a) Stand “900”, b) stand “950”