Specialty slide rule at the antique store

[ChemAir]

It still has the guide cards for how to read it for different types of valves, etc... I found it in a small town store, outside Nashville, TN, USA, picked it up because I haven't seen one of these before. A little tedious to use, but, it is more capable than I would've thought. Thought someone other than me might think it was neat.

 

[jrmichler]

Slide rules are useful for quickly and easily comparing different alternatives. And they are a negligible source of error in fluid flow calculations.

This one was given to me back when I was buying a lot of Masoneilan control valves.

 

[ChemAir]

Slide rules are useful for quickly and easily comparing different alternatives. And they are a negligible source of error in fluid flow calculations.

I haven't seen the Masoneilan version of that one. Most of the interesting rules I've seen or had, found new homes very quickly, usually being lent out by those I lent them to. Somewhere there's a large repository of steam tables, relief valve calculators, nomograms, product data sheets...

I use the Dwyer velocity pressure slide rule all the time. I guess I could have done a spreadsheet for that, but it never really seemed necessary. Also, carrying a computer into some of the hellholes I go into check airflows would be problematic.