Process procedures for machining, technical personnel according to the number of products, equipment conditions and quality of workers, etc., to determine the process used, and the relevant content written into the process documents, such documents are called process procedures.

In order to facilitate the preparation, execution and production organization and management of process procedures, it is necessary to divide the process into units of different levels. They are process, installation, work station, work step and tool walking. Among them, the process is the basic unit of the process.

The machining process of a part consists of several processes.

Work process

A (or a group of) workers, in a workplace (or a machine tool), on a (or at the same time on several) workpiece continuous completion of that part of the process called the process. The basis for dividing the process is whether the workplace changes and whether the work process is continuous.

For example: in the lathe processing a number of axes, both for each axis continuously for roughing and finishing, but also for the entire batch of axes for roughing, and then in turn for their finishing.

In the first case, the machining consists of only - one process; in the second case, due to the interruption of the continuity of the machining process, it becomes two processes, although the machining is performed on the same machine tool.

The work process is the basic unit that makes up the process and is also the basic unit of production planning.

Mounting

In the machining process, so that the workpiece in the machine tool or in the fixture to occupy a correct position and be clamped in the process, known as clamping. Sometimes, the workpiece on the machine requires multiple clamping to complete - a process of work content. Mounting is the part of the process that is completed after a workpiece has been clamped

For example, in the lathe machining axis, first from one end of the processing of part of the surface, and then turn around and then process the other end, when the process content includes two installation.

Workstation

The use of rotary (or shift) fixtures, rotary tables or multi-axis machine tools in the processing, the workpiece in the machine once after clamping, to go through a thousand positions in turn for processing, the workpiece in the machine occupies each position completed on the - part of the process known as the workstation

In simple terms, the part of the workpiece that is completed in each machining position relative to the machine or tool is called a workstation.

Work step

In the machining surface, cutting tool, cutting speed and feed constant conditions, the continuous completion of the part of the process content called the work step. It is also often called "feed" in production.

In order to increase productivity, several tools are used to machine several surfaces at the same time, and the work step is called a compound work step, which can also be regarded as a work step.

Tool walking

Machining tool on the processing surface of the work step completed once part of the work step is called walking tool.

For example, if the shaft parts to cut away the metal layer is very thick, it is necessary to cut several times, then each cut is called a walking tool. Therefore, in the cutting speed and feed amount of the premise of the same tool to complete a feed movement is called a walk.