Skewness
Skewness
(OP)
I have recently joined this spring manufacturer, but it seems has got a problem when it comes to spring squareness.
There is too much resetting of springs(which i would call rework) due to springs being skewed(not square). I will explain the process now. The springs during manufacture a passed through a moving quenching oven, where they are heated to a temperature that will make them ready for quenching and then are tempered after quenching and then ground and Tested for squareness. When testing for squareness a higher percentage is skewed. The process will go back then to try and eliminate the skewness i.e. reworking, whereby we have to heat them again and re-temper them again.
The spring has the following specs: wired diameter d = 14mm, Free Length 243mm, ID 50mm, end grinding is 270-340 degrees.
For those that have encountered the problem of squareness, how did u solve such a problem...Thanks.
There is too much resetting of springs(which i would call rework) due to springs being skewed(not square). I will explain the process now. The springs during manufacture a passed through a moving quenching oven, where they are heated to a temperature that will make them ready for quenching and then are tempered after quenching and then ground and Tested for squareness. When testing for squareness a higher percentage is skewed. The process will go back then to try and eliminate the skewness i.e. reworking, whereby we have to heat them again and re-temper them again.
The spring has the following specs: wired diameter d = 14mm, Free Length 243mm, ID 50mm, end grinding is 270-340 degrees.
For those that have encountered the problem of squareness, how did u solve such a problem...Thanks.





RE: Skewness
RE: Skewness
RE: Skewness
RE: Skewness
RE: Skewness
I suppose you mean for crush grinding like, but we use water vertical grinders and we have fixtures to hold the springs in position whilst grinding. At first i thought it was the quenching oven, where we heat the springs before quenching that was causing the problem, but it has minimum contribution. Maybe i should look at the dynamics that goes on during grinding.