Oil-saw slow wire cutting, also known as low-speed wire cutting, is a CNC machine tool that uses a continuously moving fine metal wire called an electrode wire, typically copper wire as the electrode, to subject workpieces to pulsed spark discharges. This process generates temperatures above 6000 degrees Celsius, eroding metal and cutting the workpiece. The principle of slow wire cutting technology involves developing a gap between the on-line electrode and the workpiece material, continuously utilizing the discharge to remove metal.

Due to the slow wire electrocuting process utilizing a continuous wire electrode feeding method, the wire electrode is processed during its movement. Even if the wire electrode is lost, it can be continuously replenished, thereby enhancing the precision of the parts. The surface roughness of the slow wire electrocuting process typically reaches Ra=0.8μm or higher. The roundness error, straightness error, and size error in the slow wire electrocuting process are significantly better than those in the rapid wire cutting. As a result, the slow wire electrocuting process is widely used in high-precision parts manufacturing, not only in early small and medium-sized companies but also extremely common in large-scale processing factories in industries like aviation and automotive logistics.