The consistency of the interior surface has a great impact on the quality of the aseptic system process. By means of polishing, the interior contact surface is reduced. The specified surface quality of the valve body is achieved through mechanical polishing and electro polishing. According to the standards, SED offers surfaces with a surface finish up to a quality of 0,25 μm and 10 Ra. At SED, the stated surface finish always describes the maximum surface roughness value.

The surface finish is reached by automatic or manual mechanical polish processing. The methods that are applied depend on the internal contour and size of the valve body.

The valve body surfaces with the highest quality are polished with different grit sizes up to size 400.

The advantages of premium surfaces are a smoother interior surface as well as the reduction of the contact between the surface and the process medium. Thus, more efficient cleaning and sterilization, a lower risk of contamination by process fluids, and a lower danger of product adhesion to the interior surface is achieved.

Electro polishing is an electrochemical process in which the polishing part serves as the anode and copper, for instance, as the electrode. The valve body is submerged into an electrolyte solution and a voltage between 2 and 25 volts is charged. Through the current, a strong chemical reaction develops which removes material from the anode. According to the standardized procedure, the process, at least 20 μm of the surface material need to be removed. The highest metal removal is achieved at the peaks of the metal surface.

Allocation to the standard ASME BPE table SF-6: