Valve Spring Retainer to Spring Size

[blykins]

It varies from application to application is what I’m trying to tell you.

And that is what I'm try to understand, why.

Because material strengths vary.  Because there are different sizes of retainer/lock combos, a 10° lock takes up more real estate than a 7° lock. Because spring wire can be round, ovate, etc.  Because a 4000 rpm spring has different properties than a 9000 rpm spring.  You're not going to be able to come up with a one-size-fits-all rule. 

Manley's 22431 spring will work with several of their retainers.  It's a 1.550" OD spring.  Their Super 7 TensileMax retainer is 1.420".  Their H13 10° tool steel retainer is 1.440".  Their 10° titanium retainer is 1.500".  Tons of variables that can't be tied down to one specific rule.

[Falcon67]

https://www.hotrod.com/articles/hrdp-1011-what-you-need-to-know-about-valvesprings/

https://www.enginelabs.com/engine-tech/engine/valve-spring-tech-overview-of-valve-spring-design-dynamics/

https://www.hotrod.com/articles/hppp-0902-comp-cams-valve-spring/

Springs vary a lot, depending on the wire diameter, wind, material, associated assembly (free, double w/damper, conventional, behive, etc), spring rate and other factors.  Then the cam comes in to hammer the spring and all kids of things start to happen based on lobe design and such.  So the loads on the retainers can vary a lot.  And the type of material used in the retainer varies, which also changes the design.  Titanium is light weight, but under certain conditions the spring can shred the retainer because titanium is a soft metal.  Retainers will - I imagine - require a certain Rockwell hardness depending on the end use.  Too soft or too hard can both cause fatigue failures.   

[frnkeore]

Retainers will - I imagine - require a certain Rockwell hardness depending on the end use.  Too soft or too hard can both cause fatigue failures

.   
Falcon,
Thank you for the links but, they don't cover retainer size, only some stuff on keepers.

I'm a retired machine shop owner (still have the shop) that did aircraft work, mostly. For 4130 and 4340 AQ (aircraft quality) steel, the industry standard hardness is 38-42 RC for the best hardness to fatigue ratio and all inside cuts must be generated with a radius, as described by the engineer that designs the part. But, before that, the part must be rough machined and then heat treated, before finished machined. They are then MPI inspected and plated, to be a finished product.

I can only hope that retainers are made to those standards.

Brent,
Are you saying the the keeper size dictates the retainer diameter???

Again, all I'm asking at this time, is the minimum retainer size for a given spring diameter and wire size. I like to use the mean diameter as that reflects both OD & ID of the outer spring. Multiple enter springs are already, fully covered so it's not a issue.

I was hoping to get a real life answer here but, it looks like I need to talk to cam and spring manufacturers.

[blykins]

Retainers will - I imagine - require a certain Rockwell hardness depending on the end use.  Too soft or too hard can both cause fatigue failures

.   
Falcon,
Thank you for the links but, they don't cover retainer size, only some stuff on keepers.

I'm a retired machine shop owner (still have the shop) that did aircraft work, mostly. For 4130 and 4340 AQ (aircraft quality) steel, the industry standard hardness is 38-42 RC for the best hardness to fatigue ratio and all inside cuts must be generated with a radius, as described by the engineer that designs the part. But, before that, the part must be rough machined and then heat treated, before finished machined. They are then MPI inspected and plated, to be a finished product.

I can only hope that retainers are made to those standards.

Brent,
Are you saying the the keeper size dictates the retainer diameter???

Again, all I'm asking at this time, is the minimum retainer size for a given spring diameter and wire size. I like to use the mean diameter as that reflects both OD & ID of the outer spring. Multiple enter springs are already, fully covered so it's not a issue.

I was hoping to get a real life answer here but, it looks like I need to talk to cam and spring manufacturers.

Absolutely.  A larger or smaller hole in the retainer affects the strength. 

I know what you're asking for, but there's not a direct answer to it, because it depends on too many things.   What material?  What angle?  Did you see my post above where one retainer was 1.500" and the other was 1.420"? 

You're gonna drive me to drinkin', Frank.

[My427stang]

Retainers will - I imagine - require a certain Rockwell hardness depending on the end use.  Too soft or too hard can both cause fatigue failures

.   
Falcon,
Thank you for the links but, they don't cover retainer size, only some stuff on keepers.

I'm a retired machine shop owner (still have the shop) that did aircraft work, mostly. For 4130 and 4340 AQ (aircraft quality) steel, the industry standard hardness is 38-42 RC for the best hardness to fatigue ratio and all inside cuts must be generated with a radius, as described by the engineer that designs the part. But, before that, the part must be rough machined and then heat treated, before finished machined. They are then MPI inspected and plated, to be a finished product.

I can only hope that retainers are made to those standards.

Brent,
Are you saying the the keeper size dictates the retainer diameter???

Again, all I'm asking at this time, is the minimum retainer size for a given spring diameter and wire size. I like to use the mean diameter as that reflects both OD & ID of the outer spring. Multiple enter springs are already, fully covered so it's not a issue.

I was hoping to get a real life answer here but, it looks like I need to talk to cam and spring manufacturers.

Absolutely.  A larger or smaller hole in the retainer affects the strength. 

I know what you're asking for, but there's not a direct answer to it, because it depends on too many things.   What material?  What angle?  Did you see my post above where one retainer was 1.500" and the other was 1.420"? 

You're gonna drive me to drinkin', Frank.

As a military guy, I wish I had not only a MIL standard, but adherence to it across manufacturers that had to meet common interchange requirements.  Unfortunately, even though we say the engineering and product development is far better than it ever has been, and it is, you won't find those common standards, you may find rules of thumb that work across manufacturers, but in the end, just so many differences in manufacturing and material treatment

I think the best thing is to keep things small, think about managing harmonics and weight, and try not to push individual components to the edge.  If the retainer needs to be small, find a design that meets the requirements that is small.  It would be handy if it was different, but it just is what it is

[Falcon67]

I used to be a QA guy in a manufacturing co., so I get your deal on MIL-SPEC things and engineering prints, material specifications and such. 
My Howards catalog has 13 moly retainers listed and 9 titanium