Machining

Manufacturing refers to all the processes that are used to convert raw materials or scrap into useful products by adding substantial value. In order to satisfy perpetually growing demand a large number of manufacturing processes has evolved in order to process a wide variety of materials in innumerable ways. All such processes can be broadly classified into three groups, as enlisted below.

  • Primary Manufacturing Processes—Such processes are used to convert raw material or scrap to a basic primary shaped and sized product. They usually cannot provide exactly same product that is desired (unless the required product has very ordinary & simple shape with broad allowance on dimensions). Examples include casting, forming and joining.
  • Secondary Manufacturing Processes—These processes are used to further modify the output of primary manufacturing processes in order to improve the material properties, surface quality, surface integrity, appearance and dimensional tolerance. Machining and various surface treatment processes come under this group.
  • Advanced Manufacturing Processes—These are newly emerged processes that can directly convert raw material or scrap into products having close tolerance and dimension, superb surface quality, desired properties and magnificent appearance. Such processes employ computer system for various purposes and a sophisticated and high resolution machine tool for processing. Powder metallurgy and rapid prototyping come under this category.

By definition, machining is one of the secondary manufacturing processes by which excess material is removed by shearing from a pre-formed blank in the form of chips using a wedge shaped cutting tool in order to get desired shape, finish and tolerance. It is one subtractive manufacturing process that can produce reasonably good surface finish and intricate shapes with close tolerance. Once again, there exist a number of machining processes to cut variety of materials in several ways. Various topics related to conventional machining are provided below.


Introduction to conventional machining

Articles related to basics of production, manufacturing and machining; primary, secondary and advanced manufacturing processes; and additive manufacturing and subtractive manufacturing are provided here. A concise definition of machining or metal cutting is also given. Relationship among machine, machine tool and cutting tool is described here. Browse all topics…


Cutting tool or cutter

Cutting tool is a sharp edged wedge shaped device used to remove excess material from workpiece during machining. Classification of cutting tools—single point and multi-point; Geometry of cutting tool; designation of various features; conversion of tool angles; etc. are discussed here. Browse all topics…


Principle of metal cutting or machining

This part is devoted to the fundamentals of metal cutting. Articles related to basic cutting parameters, material removal rate (MRR), cutting force and power, surface quality, machining performance, etc. are presented here. Quality of machined surface and machinability issues are also given here. Browse all topics…