Surface Roughness: Need to Know to Minimize Costs
Many manufacturing processes how a speed-surface smoothness trade-off. Smooth surfaces require the machine to “go slower”.
Ignoring this information can affect your quoting accuracy. On the other side, you can check our tips on what you need to know to minimize costs.
Surface finish is the specified smoothness required on the finished surface of that part. This surface finish can be obtained by machining, grinding, honing, or lapping, etc. Surface finish is generally required for mechanical components where these components must fit together perfectly, move against each other, or form a sealing interface.
Surface texture includes characteristics such as roughness, waviness, lay, and flaws.
Basic Symbol
Standard surface finish symbol. The surface may be produced by any method.
Material Removal by Machining Required
The horizontal bar added to the basic symbol indicates that, material removal by machining is required and extra material must be provided for that purpose.
Material Removal Prohibited
The circle added to the basic symbol indicates, the surface must be produced by processes such as casting, forging, hot finishing, cold finishing, die casting, powder metallurgy or injection moulding without subsequent removal of material.
Surface Finish Parameters
a - average roughness value (Ra)
b - production method, coating, note, or other additional information
c - roughness sampling length in millimeters or inches
d - direction of the surface lay
e - minimum material removal requirement in millimeters
f - alternate surface finish parameter
Other Type of Surface Finish Symbols
N-Grades
Surface Roughnesses can be complicated, and the similarity of the symbols across various standards contributes to this complexity. N-Grade converts the specified roughness to a value between "01" and "12". This simplification eliminates the need to consider the various standards, such as the distinctions between average profile height and maximum profile height, etc. These values are calculated by WERK24 whenever possible. Werk24 converts surface roughness parameters to N-Grades according to the following table.
