What valve seat material for Titanium Valves. 3

[ZoRG]

Hi

The maker of the valves suggests using a bronze based seat, what are the best bronze based material to use?
What about copper based materials for valve seats?

Thanks.

 

[ZoRG]

From Columbia metals since they are a supplier of these.

Hardness:
TROJAN : HB200Minimum 230-270Typical
Copper Beryllium : HB180
Colsibro : HB200

COLSIBRO is a Copper Nickel Silicon alloy which offers a remarkable blend of properties at a non exotic price.

 

[rpmag]

Zorg, what is the price difference between those materials in your experience?

 

[ZoRG]

They are all expensive
Colsibro is the cheapest afaik, then Trojan, then CB I think trojan and CB are about the same, they don't differ by that much in raw form. Colsibro is not compatible with titanium though. And if your head porter doesn't have a respirator, go with trojan.

 

[DeSotohead]

The new Corvette engine (the 7.0L Gen-IV smallblock) is using a material for the Titanium intake valves (manufactured for GM by DelWest) called PMF-28.
Has anybody heard of this material, what its composition is, and where possibly to get it?
I cannot believe that GM would be using BeCu due to toxicity issues in their manifacturing plants, and these heads are assembled by GM in a Wixom facility (requiring valve lapping).

 

[WilliamH]

ZoRG,

In another thread, I believe you mentioned that you had Ti valves made in Russia. Did you have to pay a duty on these parts since the Bush administration imposed a protective tariff on Russian Ti? I think this tariff went into effect in November of 2004.

Also could you comment on the quality of the valves you had made in Russia?

Thanks in advance.
Will

 

[ZoRG]

Hi

I am not in the US, but they were sent there first of to the head porter, there were no import duties on the valves, but it was before November 2004. The quality is very good.

Have a look at the site :

http://www.titanium-valve.com/english/index.htm,

the price with shipping was around $685 for a set of polished valves, but you should only have them polish the inlet ones. That price includes shipping via UPS which was $100.

Cheers.

 

[WilliamH]

ZoRG,

Thank you for the information.

Will

 

[jjam]

Hi, I am new to this forum. However, I am both a gearhead and the Director of Technology for a domestic beryllium copper manufacturer. If anyone has any specific questions about this material, please let me know.

jjam

http://www.freedomalloysusa.com

 

[bobqzzi04]

jjam,

Any thoughts on the thermal conductivity of CuBe as compared to steel when used as a valve seat?

Also is it possible to run an inconl valve on a CuB seat?

 

[jjam]

bobgzzi04,

CuBe alloys are used in plastic mold applications due to the excellent thermal condustivity and extremely wear resistant surface. The cycle times in a CuBe mold will be much faster than in a comparable steel mold. The thermal conductivity of CuBe is far superior to steel. Depending on the alloy of CuBe, it can be 3 to 10 times higher.

An Inconel valve should not be a problem at all. CuBe alloys and virtually all nickel based alloys that I have run across work well together. Unlike many other metals, CuBe also works well when run with or against itself. 2% CuBe alloys have rotational bearing type galling values around 100KSI when run against other 2% CuBe alloys. That is extreme to say the least. When you compare these numbers to other typically high performance bushing alloys,like the various Ampco's, you find that the CuBe alloy properties are often 2-3 times better.

2% CuBe alloys will hold peak properties in intermittent or continuous use at up to 625F. --.5% alloys will hold to about 800-850F. The properties of the two alloys though are very different. 2% alloys are typically HRc40 with 30% IACS electrical conductivity vs. .5% alloys with HRb 95 and 50% IACS conductivity.

If you need something even more robust, we make a NiBe alloy that will maintain HRc 50-55 at 900-1000F continuous.

Although I have seen the various NON-beryllium alloy ads touting better properties than CuBe, like Trojan, it is just not true. I have no idea where they get their CuBe property data, but it is not representative of CuBe's best. If it were possible, my company would be out of business. Beryllium containing alloys continue because they can and do perform in critical and severe duty applications where other metals will not. IF there were a lower cost and more traditional material that could perform like CuBe, there would be no market for CuBe. This is definitely not the case. Don't believe everything you read in metal ads.

jjam