The cast parts are transferred to the machining department and precision machining is carried out in 5 axis or 3 axis CNC vertical machining centers or CNC lathes. Leakage test and pressure test are performed as needed. CNC (Computer Controlled Machine) machining is the process of machining surfaces in a CNC (Computer Controlled Machine) milling machine according to a run program. This process uses the milling machine's three axes (x, y and z axes) and also uses two rotary axes (a and b axes). In this way, the milling machine enables surfaces to be processed in three dimensions and therefore very high precision and dimensions can be processed. 5-axis or 3-axis CNC machining is used for the production of a wide variety of products and is frequently used in areas such as automotive, aircraft, and industrial equipment.