rod surface finish
rod surface finish
(OP)
Is anybody aware of any standards for surface finish for rods in dynamic sealing applications? We are using a double lip seal in a pump on our rods and have continuous leakage issues. Our current rod spec calls for 8-16 Ra which I think is way too rough. I have found some various ISo standards but nothing specific. An RMA OS 1-1 spec I have found does go into some details but will have to buy it to know for sure(unless someone is familiar with it here).
When we can pinpoint a finish we want, I need to understand the best way of specifying. As just an Ra finish leads some interpretation. I would like to expand upon it with Ra, Rz and Rpm values but need to determine what those should be for this type of sealing application.
Any help that could be provided would be appreciated.
When we can pinpoint a finish we want, I need to understand the best way of specifying. As just an Ra finish leads some interpretation. I would like to expand upon it with Ra, Rz and Rpm values but need to determine what those should be for this type of sealing application.
Any help that could be provided would be appreciated.





RE: rod surface finish
RE: rod surface finish
RE: rod surface finish
Have you found a simple Ra designation is adequate to obtain the required finish needed? We don't appear to be getting consistent results using this alone.
RE: rod surface finish
You need to supply more info. If this is rotational seal I opt out as a don't design parts that use them.
- CJ
RE: rod surface finish
RE: rod surface finish
Do they leak from new, or after an unreasonably short time.
How are you managing the oil flow internally? Is the seal subjected to full pressure? How high is that pressure?
page 2 here -
http://www.garlock.com/download.php?obj_id=2704
surface finish and lead are discussed in some detail.