Surface Roughness Of Steel Sheet

The finish provides a uniform dull surface that is suitable for painting and lacquering.

Surface roughness of steel sheet.

Galvanized steel most common material used in fabricated duct work for most comfort air conditioning systems. Regular matte this finish is widely used for most applications of cold rolled steel sheet. If these deviations are great the surface is rough if they are small the surface is smooth. 1d stainless steel is sometimes used as the starting point for polished finishes.

K roughness of duct pipe or tube surface m ft d h hydraulic diameter m ft typical duct materials and their use. Surface roughness is a measure of the texture of a surface. R k d h 1 where. Values of about 70.

The resulting surface is slightly coarse with very low reflectivity and a typical average roughness ra between 4 7 micrometers. With this steel surface roughness 653 ra range the stochastic surfaces shot blast and edt show much lower a i. The roughness as measured using a profilometer is approximately 35 to 65. R relative roughness.

Steel surface finishes are often an important aspect of custom machine parts. Cold rolled sheets are produced with the following finishes which are defined with a specific quantitative roughness values that are determined using a profilometer. The higher the grit numbers the finer the polishing lines and more reflective the finish. Sometimes steel surface finish is also referred to as surface texture or surface roughness.

Typical ra would be 0 30 0 50 µm 12 20 µin. Surface consistency is key to this type of finish. Roughness is typically considered to be the high frequency short wavelength component of a measured surface. 2b mill finishis a bright defect free finish that is produced by a final light cold roll pass on polished rolls.

Two materials shot blast and edt with extreme ra level 3 01am used in sanitary applications are tested as a reference. Relative roughness can be expressed as. There is no visible figrainfl with this finish. The surface finish of a machine part may be important to reduce friction with other machine parts or to improve the aesthetics of the part.

In practice it is often necessary to know both the ampli tude and frequency to ensure that a surface is fit for purpose 1. It is quantified by the vertical deviations of a real surface from its ideal form. Sibetex with even larger ra values between 1 5 and 21jm still show an a i.