1. Be decided by the make choice of of treatment object before object of choose and buyWant to prepare the object of treatment clearly above all. Generally speaking, the part that has following characteristic suits to machine in machining center: Multitask foreword intensive workpiece shows on a workpiece need is used a lot of have cutting tool machining. The workpiece with trival fixed position has the poriferous treatment that precision of pitch of one fixed position asks for example, use the characteristic with tall precision of machine tool fixed position, very convenient carry out. The work that duplicates type of production suits to machine sheet small lot production. Small lot points to in 1-100, capacity of every lot number is not much, but need to repeat production again. Additional, although workpiece appearance measurement is different, but it is similar work, realize group of treatment easily (the spare parts of GT) craft. The complex form workpiece such as spare parts of the part pattern of complex form, aviation, can have the aid of machines all sorts of abnormity spare partses on machining center from technology of traverse foreword staff. Casing kind, board kind the spare parts uses circumgyrate workbench on horizontal machining center, undertake to casing spare parts much face is machined, wait like cylinder body of body of main shaft casing, pump housing, a powerful person, internal-combustion engine. If connect end face to also want to install the treatment in clip, can choose pentahedral machining center. Vertical machining center suits to machine box to build crock of lid, planar cam to wait. Machining center uses dragon door at machining large casing, board kind spare parts, like pillar of diesel locomotive cylinder body, machining center, lathe bed, presswork wallboard machine. 2. The make choice of of machine tool norms machines the size dimensions of workpiece according to what decide, the workbench measure that requires a machine tool certainly accordingly and the route that 3 linear coordinate tie. Workbench dimension should make sure workpiece is above its the can great work that hold clip, treatment dimension must be inside each coordinate journey, in addition the limitation that considers the space that change a knife and area of each coordinate interference even. 3. The precision classification of the machining center of make choice of of machine tool precision is common model with nicety model, its are main precision project sees next tables: Machining center is main project of precision project precision is average model (Mm) nicety (whole journey of 0.005/ of ± of whole journey of 0.01/ of ± of precision of Mm) linear fixed position repeats ± of fixed position precision 0.006 ± 0.002.