HAVE YOU EVER HEARD OF SOMEONE DOING THIS? 5

[cryovette]

Has anyone ever heard of the placement of a valve into (through) a piston before?

 

[israelkk]

Sure, depends on the application and type of valve. I have seen this in an aerospace use. Please describe the application and reasons.

 

[NickE]

This is done all the time on certain types of small vaccumn/pressure compressors. Many are manufactured by GAST or Thomas.

 

[zdas04]

I would guess that the "small" reference is pretty important. I wouldn't think that you would be successful pushing very many hp through a set of valves on a piston.

David

 

[dcasto]

do you mean this? IR VIP Compressors?

http://204.168.68.51/e-tech/PDF Files/tp009.pdf

 

[zdas04]

Ok, I take the back the "small" statement. I've never heard of these beasts being marketed (and I've been involved in a bunch of Ajax acquisitions), any idea what their market is/was?

David

 

[dcasto]

I've operated two of the IR VIP machines. One was in gas gathering near Canadian, TX. The compressor was driven by a cat398. The other was in air service, compressing air to a Nitrogen generator system, again driven by CAT 398.

Notice I said "was".

 

[nickelkid]

The IR VIP was a great idea, but it was all downhill from that point forward

 

[cryovette]

Thanks for the info everyone! To answer your question, IsraelKK, the application is for a pressure boost from roughly 175psi to 500psi and a volume of about 240 cubic inches...roughly. So what happened with this IR VIP machine? Is it now defunct?

 

[nickelkid]

It looks like DR still offers the VIP

http://www.dresser-rand.com/gfc/lit.asp

 

[HPMach]

Recently there is a safety issue raised by IR on VIP units. VIP units are there in market for almost 10years.

 

[Isobella]

VIP compressors are a very rare beast. Only end user I know outside of the US is Petrovietnam (Vung Tau),pumping natural gas, mol 21.2.
These machines are 4 cylinder, single stage. 900 rpm.
Inlet 675 psia @ 77 F
Delivery 1643 psia @ 190 F
The inboard and out board heads act as inlet valves. and the pistons double as (delivery) valves,they also carry the piston and rider rings.
Not (in my opinion)user friendly when it comes to maintenence.
Plenty of information available on Dresser site.

FYI, Thomassen also make use of a valve in piston on their "floating piston" machines, but this is to pressurise the piston which allows the gas to bleed back and float the piston during operation.