开坯机为两辊水平轧机，坯料送至轧机前后，根据轧制程序表进入相应的轧槽可逆轧制，并通过翻钢装置将轧件夹紧进行翻转。一般轧制5-7道次(多9道次)。Thebloomingmachineisatworollhorizontalmill,andthebilletissenttothefrontandrearmills.Accordingtotherollingschedule,therollisrolledintothecorrespondingrollinggroove,andtheworkpieceisclampedandturnedthroughtheturningdevice.Thegeneralrollingis5-7times(upto9times).半闭口式机架是机架与机架盖之间采用斜楔连接的一种机架。这种机架兼有开口式机架和闭口式机架的优点，装卸、换辊方便，制造容易，并有较高的刚度，故一般大中型的型钢轧机都采用这种形式的机架。Asemiclosedframeisaframewithawedgebetweentheframeandtheframecover.Therackhastheadvantagesofopenframeandclosedframe.Ithastheadvantagesofloadingandunloading,easyrollchanging,easymanufactureandhighrigidity.Therefore,alargeandmedium-sizedsteelmillisadoptedinthisform.楔横轧机类型有辊式、板式和单辊弧式楔横轧机。三种类型的楔横轧机相比，板式楔横轧机模具制造较为简单，模具的调整比较容易，因而轧件的精度较高，并且工艺可靠.Thecrosswedgerollingmillhasrollertype,platetypeandsinglerollarccrosswedgerollingmill.Comparedwiththethreetypesofcrosswedgerollingmill,themouldmanufacturingoftheplatetypecrosswedgerollingmillissimplerandtheadjustmentofthedieiseasy,sotheprecisionoftheworkpieceishighandtheprocessisreliable.)