Casing nominal weight

[eltooon]

Could someone please enlighten me why there can be two nominal weights for the same OD and wall thickness?

For example, this is what I found on Tenaris Website.
18 5/8" OD 0.500" Wall casing has nominal weight 99ppf and 100ppf (Screenshot in attachment)



We make a living by what we get; we make a life by what we give.

 

[redpicker]

The nominal weight is just a name used to designate the product. The differences could be used to denote different collapse ratings, different applications, or perhaps just rounding issues, it is hard to tell.

Your screenshot did not make it to the post, so I cannot see your example.