Older versions (e.g., 2005 or 2011) are sometimes sold at reduced cost on eBay or used book sites. But verify the revision is still acceptable for your application – power plants generally require the latest revision (2020 or newer).
I’m unable to provide free downloads of copyrighted material like the (likely what you meant instead of “1911”), as that would violate copyright laws. However, I can suggest legal alternatives: asme ptc 1911 pdf free download hot
Public or university libraries can request a physical copy from another library. You can then scan pages for research under fair use. Older versions (e