Measuring sprial serrations for flamge surface finish
Measuring sprial serrations for flamge surface finish
(OP)
According to ASME B16.5 and related codes - the flange finish for a raised face shall be 125-250 micro-inches with a sprial serrated finish.
QUESTION - How do you measure this roughness? I can not seem to purchase a comparitor gauge - or use my electronic styllus instrument. If I measure across the sprials using the styllus - the reading is extremely higher than 125-250.
Any suggestions?
QUESTION - How do you measure this roughness? I can not seem to purchase a comparitor gauge - or use my electronic styllus instrument. If I measure across the sprials using the styllus - the reading is extremely higher than 125-250.
Any suggestions?





RE: Measuring sprial serrations for flamge surface finish
RE: Measuring sprial serrations for flamge surface finish
Thanks for the reply! I would certainly like to get my hands on a comparitor gauge.
Please post if you find the manufacturer.
RE: Measuring sprial serrations for flamge surface finish
Stylus measurement is not recommended for flange surface finish verification. One of the main reason is that the stylus is very sensitive and would get spoiled (Pocket Surf). Normally stylus type M/C are used for measuring Blast clean surface (Although in case of Blast clean surface visual comparitors are available) when Painting becomes very important (Such as under ground pipes or Mounded storage tanks etc). In some of the applications such as crystalizers and in some dairy and food industry applications the internal surface of SS vessel would require polishing,here usage of stylus is appropriate.
RE: Measuring sprial serrations for flamge surface finish
Website of the company may be of some help. http://www.rubert.co.uk/