Piston ring cam sleeve

Normally you would measure the skirt of the pistons,check your tolerances and machine the cylinder to that dimension.Iam not familiar with this method that you speak of. Could you tell me more.

hi, thanks for replying to me , See basically piston rings have a pear shaped pressure distribution inside the engine bore for better performance.Inorder to achieve this while manufacturing the piston rings we need to put the rings on to outer sleeve which contains a shape which ultimately gives the piston ring the desired pressure distribution in the engine bore while engine running. Hope my details give you some direction for ideas. Please do not hesitate to ask more Have a nice day.

Hi again, When you refer to a 'pear shaped pressure distribution inside the engine bore' what are you referring to? The surface where the ring slides against the piston bore? The area of contact between the rings and the piston? Or ???? Look for a company that grinds cam shafts and then find out who grinds there master cam profiles for them. These companies are experienced in, and have the necessary equipment to make (grind) very accurate out of round shapes. If you are going to utilize heat treatment to force the rings into the shape you want, be sure to give this info to whomever you get to make these forms for you, otherwise you will end up with the form distorting when it undergoes the heat treatment along with the piston rings. If this is the case, it will be very challenging to get a form that will hold its shape. If you are going to put the rings over the outside of the form, I would suggest you have it made solid as opposed to a hollow cylinder and have it undergo SEVERAL stress relieving heat treatment cycles before the final machining. Just out of curiosity, do you want to put the rings on the inside or the outside of the out of round shaped 'forming pipe' ?

Hi, I'm not familiar with this either. But it sounds like forcing a specific out of round shape onto the piston ring utilizing heat treatment? I know that the pistons themselves are not 'regular cylinders' If the rings are cast iron, which most comercial piston rings are, they will 'relax into shape' as they go through heating and cooling cycles in the engine. Keep in mind that in most 4 stroke engines (but not those running propane) the rings are purposely left free to rotate in the pistons to allow for even wear and better sealing. These factors negate the forming of the rings to an intial out of round shape. Most 2 stroke engines have ports, and the piston rings are thus pegged to stop rotation of them to prevent the ends of the rings from being pushed out into the ports and damage the engine. Thus in a two stroke what I believe you are speaking of in order to compensate for the rings being hotter on the side with the exhaust port in it. Please provide us with more details.

I don't know what you are attempting to do, but depending on the precision I would start contacting companies that make pistons and rings and inquire there. You can get as exotic as you want and go to suppliers of F1 racing if you want.