ArdKapteijn
Mechanical
Hello,
I'm redesigning a entire valve range at the moment, which has a couple of problems.
The biggest problem at the moment is cold welding in the stem rolpin construction. The rolpin is fixed so it has to slide by the stem, the contact area can be considered a line contact with a area of 0 mm2.
This means that the rolpin (made of stellite) forges himself into the stem (made of 17/4PH).
I already made a calculation with a expected contact area with a max yield that can't be higher then the 0.2%Yield of 17/4ph (Stainless Steel – Grade 630 - 1150), but this calculations doesn't ensure cold welding :S
My question is: Is there a way to calculate cold welding? Or a calculation/method to minimize the risk of cold welding.
Notice: Lubrication is NO option!
Appreciate any or all help.
Thanking y'all in advance,
Regards
I'm redesigning a entire valve range at the moment, which has a couple of problems.
The biggest problem at the moment is cold welding in the stem rolpin construction. The rolpin is fixed so it has to slide by the stem, the contact area can be considered a line contact with a area of 0 mm2.
This means that the rolpin (made of stellite) forges himself into the stem (made of 17/4PH).
I already made a calculation with a expected contact area with a max yield that can't be higher then the 0.2%Yield of 17/4ph (Stainless Steel – Grade 630 - 1150), but this calculations doesn't ensure cold welding :S
My question is: Is there a way to calculate cold welding? Or a calculation/method to minimize the risk of cold welding.
Notice: Lubrication is NO option!
Appreciate any or all help.
Thanking y'all in advance,
Regards