Butterfly Valves- Pro's and Con's for Fire Sprinkler Applications

Just a quick video showing everyone what a butterfly valve is with an internal view of the butterfly valve components. Advantages and disadvantages of a butterfly valve. This video was really intended for new apprentices in the trade who just want a crash course/introduction to parts. As I start providing more content I don't want to keep on explaining the same parts over and over again so I'd like to kind of start at the basics and work my way up so when I get into more intermediate/advance level content I won't feel the need to spend time explaining smaller parts which would take time away from explaining the more complicated systems in the future. Please feel free to drop a comment if you feel there's anything important that I missed that should be said.

0:00- Overview
0:55- indicating properties- moving indicating flag
1:40- physical properties of the valve/ease of installation
2:03- grooved vs wafer butterfly. Connection methods.
3:12- annual maintenance (NFPA 25)
3:35- methods of supervision (I failed to mention that many wafer butterflies are supervised using a PCVS switch). Click this link for how to install a PCVS switch.    • How to Install a Potter PCVS-2 Switch  
5:53- Hydraulics & Cavitation
6:54- Ports on butterfly valves
8:00- Orientation/Axis of Installation of a butterfly valve- Does it actually matter which way I install a butterfly valve?
9:00- Properties of water- how butterfly valves effect the flow of water
11:10- dismantling the Victaulic Butterfly valve- what does it look like on the inside? If you want to see what the inside of a wafer butterfly valve looks like, click the following link:    • How to Install a Potter PCVS-2 Switch  
12:00- Testing the butterfly valve (testing for supervision as per NFPA 25)
13:30- Testing the butterfly valve with a multimeter
14:20- Off the record- how does Victaulic manufacture a model 705 butterfly valve (supervised normally open control valve) vs how Victaulic manufactures a model 707 butterfly valve (supervised normally closed control valve)