Precision injection molding will be affected by many related factors and environmental conditions, and the most basic is the plastic material, injection mold and injection process and injection equipment. In the early stage of designing plastic products, the engineering plastics can be selected according to its environment first. Secondly, the selection of plastic materials, as well as finished dimensional accuracy, product weight, quality requirements and expected mold structure to choose the appropriate injection molding machine.

Mold, which is all kinds of tools from industrial production for injection molding, blow molding, extrusion, die casting or forging molding, smelting, stamping and other methods to get the required products. In short, a mold is a tool used to make a molded object. This tool is made up of various parts, and different molds are made up of different parts. It mainly through the change of the physical state of the forming material to achieve the shape of the processing, which is known as the "mother of industry". A tool that makes a blank into a product of a particular shape and size under the action of an external force. Widely used in punching, die forging, cold heading, extrusion, powder metallurgy parts pressing, pressure casting, as well as engineering plastics, rubber, ceramics and other products pressing or injection molding processing.

Turning tool belongs to a single blade tool. There are many types of turning tool due to the different shapes of cutting workpiece，but the name and function of each part are the same. A good turning tool must have two parts：good rigid handle and sharp blade.The blade angle of turning tool affects cutting directly. Different turning tool materials and workpiece materials result in different angle of the blade. Lathe tool has four important angles: front clearance angle, edge clearance angle, back bevel angle and edge bevel angle.

Grinding wheel is an important tool for grinding. It is a porous object composed of abrasive and binder. Abrasives, binders and pores are the three basic components of the grinding wheel. It has an important influence on the grinding precision, roughness and production efficiency.