Form fill and seal machines uses inflated air bags to perform sealing. I have seen them using Wabco valves in the earlier days, but now they comes with Bosch Rexroth, I have been hearing Bosch bought over it.
Only difference of these valves I notice is
- Sturdy plastic body, blue color
- Easily removed from the base with quick release
- Instead of a spool design to switch the port, they was having a diaphragm type, I guess this gives them an edge on how big the orifice can be to fill faster.
- And as Jesper mentioned, they do have big quick exhaust valve close to the air bag. They need those due to the fact to deflate the air bag quickly.
- But not cheap
BTW, the valves were 3/2 way with single port output.
Regards