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honey1
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Join Date: Sep 2007
Posts: 8

Valve Pocket

12/12/2007 11:10 AM

what is the function of valve pocket made on the piston head in the engine?
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Horrible Old Bat
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#1

Re: valve pocket

12/12/2007 11:28 AM

It's to give clearance for the valves to open at top-dead-centre between the blow stroke and the suck stroke, while maintaining a high compression ratio.

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CSM Engineer
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#2
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Re: valve pocket

12/12/2007 12:09 PM

I can tell you that if that clearance is not there, the engine will make a horrible noise...but only briefly! I learned early to place a bit of modeling clay on the top of my pistons and roll the engine over by hand to check the clearance before final assembly. A 0.025" clearance (without the head gasket) is absolute minimum.

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Steve S.
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#3

Re: Valve Pocket

12/12/2007 5:58 PM

Are you talking about an engine or a reciprocating compressor? For a recip compressor the valve pockets are used for compressor capacity control.
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ronald
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#4

Re: Valve Pocket

12/12/2007 7:37 PM

To accomodate the valve; problems that arise from bad timing amd assembly have, at least, a degree of freedom from smashing the piston against the valves.

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Previous in Forum: Taking Advantage of Atmospheric Moisture   Next in Forum: FINITE ELEMENT ANALYSIS: of parts of symmetrical models.

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