There is a small old time hardware store in Batesville runs the same crackers. Have seen em run as many as 4 at a time and buys direct from Dukes in the BIG bags we used to get 2000 lbs of corn starch in when worked at US Gypsum. They run compressed air in these cracker/shellers and each nut fits into a moving slot. I have a habit of tearing things apart to see what makes them work LOL
Those cracker/ shellers are pretty complex and had issues with the O-rings when they first came out. I imagine they have address that issue by now. I started with a cracker like everyone else used around here and it would drive you to drink. Had to change pocket’s in them all the time to fit the size of the nut. Top speed on them was 35 nuts a minute and that was just cracked. Customer still had to dig the meat out of the shell. I soon sold that and bought a new sheller on the market that didn’t care what size pecan you poured into it and would shell over 200 per minute, plus blow the shell off. It runs off a 110 moter. I have had to disassemble it and reweld and beef up some of the factory parts after a few years though. They do not like an occasional rock run through it with the pecans your pouring in.