API-610 VS6 Lock Washers on Bowl Studs or not?

[DRhodes]

I am having trouble finding direction on whether to use lock washers on the bowl studs for an API-610 VS6 pump. I have looked through the spec, but I am not finding any guidance. I have also searched manufacturer's IOMs and technical manuals and I do not see them used, but NOT directly called out as DO NOT USE lock washers. So, my default conclusion would be if the stud is torqued correctly then a lock washer would not be needed.

Am I just looking past the section I need in the API-610 spec...????

 

[TugboatEng]

Lock washers is a very broad term. Is there a specific type you intend to use? Generally, lock washers don't live up to their name and should not be used.

 

[DRhodes]

The technician wants to use split ring style.

 

[TugboatEng]

You can read it here:

https://ntrs.nasa.gov/api/citations/19900009424/downloads/19900009424.pdf

I also want to add that nearly all types of lock washers allow corrosion of the threads and seizing of the fastener as they typically have openings and gaps that let moisture under the head of the nut where it can do serious damage. Split lock washers also can break and exit out from under the fastener.

 

[DRhodes]

Thank you for the reference material. This what I needed.