One item on the pipeline list
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This post was last edited by wingman1985 on 2009-8-12 at 14:54. While translating the pipe specification list, I came across this short passage: Base Material: Carbon Steel; Rating: 150; Finish: RF, R9. I’m not sure what the parts marked in red mean – could it be the roughness value? I’m sorry everyone, I don’t have ASME B31.3 on hand, so I’m going to have to ask you all for help
This post was last edited by iamfantasia on 2009-8-11 at 15:13. Base Material: Carbon Steel; Grade 150. Finish: RF R9. Flange type: Carbon steel, grade 150 (usually expressed in pounds, i.e., PSI). Finish RF R9: Raised Face. The finish type is not certain; it might refer to surface polishing. R9 appears to be a measure of roughness, with the unit likely being microns. This information is provided for the original poster’s reference only, for mutual learning*.
Rised Face? Be careful with the spelling!
This post was last edited by echommm on 2009-8-11 at 15:31. From the red text, it’s something related to flanges. Finish refers to the surface finish of a flange; RF stands for raised face, and R9 is a designation for a specific type of surface finish. This link http://cr4.globalspec.com/thread/31536 might be useful.
Are you sure it’s an R9? Roughness is expressed in Ra, with the maximum roughness for RF being 6.3.
Three parameters for evaluating surface roughness are: the arithmetic average deviation of the profile (Ra), the ten-point height of the profile’s micro-irregularities (Ry), and the maximum height of the profile (Rz). However, the most commonly used value is the arithmetic mean deviation of the profile, Ra (the arithmetic average of the deviations of peaks, valleys, and the baseline over the sampling length, expressed in μm); the value of Ra must comply with the relevant national standards.
Answer revealed: Thank you to ecommm for the answer