Design of shield machine should be designed to follow the security concept: we must first consider the safety of operator safety protection device must meet the safety requirements of the guarantee in the use of the prescribed period has enough strength, stability, wear resistance, corrosion resistance, high temperature resistance and fatigue resistance.

It is necessary to ensure that the shield itself has enough safety and reliability. In addition, in the design of machine tool protection device, we should also consider the possible dangerous state, such as misoperation, emergencies and other special circumstances, to ensure personal safety.

Under normal circumstances, the use of fixed protective cover, often adjust and maintain the moving parts, should be priority to use interlocking type protective cover, when conditions are not allowed, with open or adjustable protective cover.

The surface of the machine tool cover should be smooth, without burrs and sharp edges and corners. It should not become a new dangerous source.