I have ordered a set of new rings for a Briggs Model 81232, except it didn't include a oil ring expander as shown in these pics:
The original oil ring is also a lot thinner than the new one. Can I use the new oil ring without the oil ring expander. It seems to be exactly the same as the oil ring that I replaced on a very similar model Briggs engine 80202. That one didn't have an expander and was thicker too. The part # I have is 294232.
Remove old ring set and install the new ring set as package and don't use any of old ring set with the new set. This was an engineering change made by Briggs.
PN 294232 replaced the 275657 standard size set originally used.
In my experience at least, the item you are talking about is called a piston ring expander. Be careful though, because there is another device also called a piston ring expander, and that second device is a tool for fitting rings to pistons, not a part of a piston ring set.
Here is a training video you might find interesting: