External protective shell or safety shield for mechanical equipment, automated production lines, laser equipment, medical instruments, etc. The main function is dustproof, anti-chip, anti-touch, noise reduction or aesthetic coverage. The structure includes door opener, removable panel, observation window, vent, etc. The material is mostly cold-rolled plate, stainless steel plate, aluminum plate, with a thickness of 0.8mm - 3.0mm, which is completed by laser cutting + bending + welding + grinding + spraying. It is required that the size is accurate, the surface is flat, and the installation interface is aligned.