Comparing Metal Finishes used in Sanitary Design Equipment

In the photo are samples that we provide to customers to show the different types of finishes available in the design and manufacturing of equipment for industries that require a high degree of sanitation.

From the left:

2B Finish: Has common corrosion resistance properties, heat resistant, smooth (not brushed) steel.  The RA (roughness average) is 36 to 15 depending on the gauge of the material.

#4 Finish:  Is Characterized by short, polished brushed lines and is suitable for caustic wash down procedures.  The RA is from 29 – 40 depending on the gauge of the material.

Pickle Passivation:  A treatment also referred to as descaling, pickle passivation removes the scale and leaves a matte finish that is free from contamination.  Apache’s tests have proven an increase in RA smoothness up to 25%, compared to measurements before the material was pickle
passivated.

Bead Blast: Bead blasting utilizes material such as glass, ceramic beads to produce a non-directional, textured surface with a satin appearance and low reflectivity. The finish is not necessarily smooth, depending on the process and blasting medium. RA readings are typically greater than 45.

Electropolish:  Surface metal is dissolved, removing all embedded contaminants, which creates a smooth, mirror-like finish.  Apache’s tests have proven to increase smoothness up to 50%, compared to measurement before the material was electropolished.

For detailed information about these finishes and processes, download our white paper “Leveraging Stainless Steel Finishes on Sanitary Equipment”.