Valve Spring Retainer to Spring Size

[frnkeore]

Knowing that smaller diameter retainers = less weight, what are the limits to how small in diameter that the retainers can be to spring diameter and is it based on mean spring diameter or outside diameter?

Or, is there any reason to have a retainer, larger than the mean diameter of the spring, itself? Assuming a good spring ID to retainer fit.

[frnkeore]

I'm surprised that there are no opinions on this.

No one specs their retainers for the springs they use?

[My427stang]

Frank, I have seen them significantly smaller many times and they work.  The weight savings would be minor as is is a savings in the thinnest part of the retainer.  Looks a little goofy to me, so I don't do it

I would much rather have a tool steel ot Ti retainer that fit the spring and/or run a smaller diameter spring if I want to save more.  Beehives work great for that reason and more

[fekbmax]

1.500 titanium light weights on 1.625 springs.

[John67427]

This is what mine looks like. Titanium retainers that are smaller than the valve spring. I did not build this engine it came from the builder this way.
Seat  320# open 850#

[blykins]

There's going to be a industry standard to it.  Most retainers are sized according to the inner diameter of the outer spring and the outer diameter of the spring itself.  The pictures these guys are putting up are about normal. 

Here's another pic, 1300 lbs open pressure with 400 lbs seat.  PAC 1.525" spring and PAC titanium retainer.

[Drew Pojedinec]

Just run a beehive.

[frnkeore]

There's going to be a industry standard to it.  Most retainers are sized according to the inner diameter of the outer spring and the outer diameter of the spring itself.  The pictures these guys are putting up are about normal. 

Here's another pic, 1300 lbs open pressure with 400 lbs seat.  PAC 1.525" spring and PAC titanium retainer.

Brent, do you mean that the industry is working on a standard or, that there is one and I will have to find it?

I know that you need to locate the spring on it's inside diameter, both top and bottom (if there is room on the bottom) but, I was hoping to find a real world, proven minimum size, based on spring diameter and wire size.

At this point, I can't see why the retainer would need to be more than the mean diameter of the outer spring, if the inside diameter is within ~.005 of the spring, assuming the retainer is strong enough for the spring pressure used.

I'm a machinist and I like dimensions, rather than how it might look.

[blykins]

It's an industry standard. 

Any retainer will not fit any spring, obviously.  When you buy a spring, the spring manufacturer will have a reference for a preferred steel, tool steel, or titanium retainer.  Some manufacturers, like Comp or Manley, will have retainers that are made for other brands.  You don't have too much leeway here, because there are 3 critical dimensions that have to be held:  the fit between the inner spring inner diameter and the retainer, the fit of outer spring inner diameter and the retainer, and the OD of the retainer versus the spring diameter.   You won't find much variation, because it's already been engineered to work with specific applications.

[Falcon67]

>When you buy a spring, the spring manufacturer will have a reference for a preferred steel, tool steel, or titanium retainer. 

This.  Buy the parts all together - springs, retainers and locks.  SHopping around is false economy, unless you know the exact specs required for the springs.  And/or you have a lathe. 

[frnkeore]

So then, no one knows what the industry standard is, the tolerance for that standard or, the engineering behind it?

There are a lot of variables, when it comes to the spring and retainer fit but,  even opinions, many of them based on "what is done" have been few and I've asked this on another forum with about the same results.

Let me ask this, are there any documented cases of retainer or spring failure, based on the outside diameter of the spring/retainer fit (not ID fit)?

There are a few types of retainers out there, 4140, titanium and tool steel and there are drilled and scalloped styles. What I'm interested in is, what is the engineering behind them and the safe limits. I would also like to know what the first signs of failure are.

[blykins]

I honestly don't understand what you're trying to do.   There's plenty of engineering behind it and most of it will depend on FEA and testing, along with a myriad of other variables, not stopping short of natural frequencies.   It will vary from spring to spring and retainer to retainer. 

The retainer size is based on the spring diameter.  The limit is when it fails.  Not trying to be sarcastic, but that's the limit, and it has to be determined in FEA or testing, or both. 

The spring I showed above is a PAC 1359 with a PAC R508 retainer.  1.522" spring OD.  Retainer OD is 1.365".  That means you have .079" of spring hanging off each side. 

[frnkeore]

I honestly don't understand what you're trying to do.   There's plenty of engineering behind it and most of it will depend on FEA and testing, along with a myriad of other variables, not stopping short of natural frequencies.   It will vary from spring to spring and retainer to retainer. 

The retainer size is based on the spring diameter.  The limit is when it fails.  Not trying to be sarcastic, but that's the limit, and it has to be determined in FEA or testing, or both. 

The spring I showed above is a PAC 1359 with a PAC R508 retainer.  1.522" spring OD.  Retainer OD is 1.365".  That means you have .079" of spring hanging off each side.

Brent,
I'm trying to understand the criteria of the retainer design. I thought between this forum and Speed Talk, I could find someone that might know how they are design and where the limits are.

You offer a spring and retainer size but, will that spring/retainer fail if the retainer is 1.300 in diameter, if so, how will it fail and how long will it take to fail? Is the retainer based on outside diameter or mean spring diameter (center point of pressure).

You didn't give the wire size but, if the retainer is some other diameter than above and if it is the mean diameter of the spring, will it fail if so, how will it fail and how long will it take to fail?

What is the minimum radius that the locator cuts for springs should be and the minimum thickness per spring pressure, for the different materials?

That's what I'm looking for answers to.

[blykins]

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

[frnkeore]

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

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