Sorry but theres havent common library for ready to use for Revit.
In every coutry have a local regulation about symbols , details , lines and etc and its impossible to provide ready to use library with all symbols and details.
My advice is to search in web bim libraries and to collect what you need for your work.
I'll get you an example why havent Revit common library ready for use:
For EU zone - all coutries in EU zone have combine standart for working on engineering/architectural projects - but its doesnt matter every coutry have her own regulation. In this case its just impossible to provide library for all of them. Its the same all over the world.
Local example:
In USA a lot of plumbing engineers use Victaulic for fire protection systems but in Russia they are not use this parts , because they have other market products with different specification. Thats mean that you can't use one library for all projects .Its depend of coutry or region.
The solution is simple 🙂
In every coutry have Bim community and if you look for members which are located in your county you'll recive your library or help for making your own library.
A little slow way to collect you library is to visit all sites and firms that was posted in previous posts.
If you need just to create a 3d model without fully BIM awards you can just use standart families in Revit. There's have pipes,elbows.tees.reducers,ducts and etc.
Other solution is to hire some Revit users to create your own library, Its the best possible way if you need BIM with high quality of end results.
If you need some families tell us what exactly try to find and we can help you .Theres no ready to use library which is 100% compleate ,safe and working.
Tell me in you need more help about this
I hope its help
Happy new year 😉
Eng. Iliev L. 



⁞|⁞ BIM Implementer, Project & BIM Manager, Coordinator, MEP Engineer
⁞|⁞ http://www.TechRoom.bg