Test of PEEK as a high pressure valve material
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Test of PEEK as a high pressure valve material
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Topic: Test of PEEK as a high pressure valve material (Read 37144 times))
rsterne
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Bob and Lloyd
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Re: Test of PEEK as a high pressure valve material
«
Reply #60 on:
December 15, 2013, 02:10:45 AM »
and a PEEk poppet SHOULD act like lower pressure inside the valve.... ie easier to open....
I have noooooooooo idea....
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
SeanMP
Plinker
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Re: Test of PEEK as a high pressure valve material
«
Reply #61 on:
December 15, 2013, 11:04:37 AM »
Im still going with the possibility that the reaction time of the solenoid is possibly fast enough to "launch" the poppet. Less mass...less launch. Possible
you could test that idea by drilling a small hole in the head of the poppet and glueing a tiny piece of lead solder in there...If the velocity changes. Well lets just say you will prove a whole bunch of my theories and leave Bob scratching his noggin
«
Last Edit: December 15, 2013, 11:09:12 AM by SeanMP
»
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Land O Lakes Ontario
"NO DELIVERY PROMISED. TAKE YOUR WORK WHEN DONE OR TAKE IT ELSEWHERE.
IF YOU MUST KNOW WHEN I WILL BE THROUGH WITH YOUR WORK THE ANSWER IS NOW. TAKE YOUR WORK AWAY. I DON'T WANT IT. I HAVE NO WAY OF KNOWING WHEN I WILL BE THROUGH. I WORK ELEVEN HOURS A DAY. DAILY INTERRUPTIONS AVERAGE ONE AND ONE-HALF HOURS.
THERE IS BUT ONE OF ME. I'M HUMAN AND I'M TIRED. I REFUSE TO LONGER BE WORRIED BY PROMISES THAT CIRCUMSTANCES DO NOT ALLOW ME TO KEEP." Harry Pope
rsterne
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Re: Test of PEEK as a high pressure valve material
«
Reply #62 on:
December 15, 2013, 12:31:35 PM »
Hey, I'm bald enough already!!!
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
rsterne
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Bob and Lloyd
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More PEEK Efficiency Data
«
Reply #63 on:
December 16, 2013, 05:01:57 PM »
Yesterday I pulled the valve from my .25 cal Disco (running up to 3000 psi) to inspect it and replace it with PEEK.... The MRod poppet, which had been modified to a 50* angle cone shape, running on custom valve with a 45* seat (so the sealing surface was near the inner edge) was polished over a width of about 0.050" and the seat was sunk in slightly, but nothing to indicate it would fail.... This valve originally had a 0.250" throat and the gun produced up to 120 FPE with a 58.8 gr. Mr. Hollowpoint, but the valve had previously been drilled to 0.266" which resulted in a drop to 111 FPE as there wasn't quite enough hammer strike even at coil bind to open the larger valve.... I reasoned that with the harder PEEK material I could risk going even bigger, so I drilled the throat to 0.281" and increased the rest of the porting from 0.22" to 0.24" equivalent, so nearly boresize.... Upon reassembly, my hunch was confirmed, as at 3000 psi it launched a 25.4 gr. JSB King through the Chrony at 1230 fps on the first shot.... Here is the testing I did with various pellets. starting at 3000 psi.... Yes, that really is 1335 fps with a 17.3 gr. Beeman Laser !!!
As you can see, with all the pellets, the first shot was the fastest, even though with the EunJins the gun shot over 100 FPE.... Once I got into the cast bullets, they were heavy enough that with the large throat I didn't have quite enough hammer strike to drive the FPE to what the gun is capable of with the QB hammer spring.... Here is a graph showing the maximum velocity and energy I achieved.... With a stronger spring, the heavier bullets would do even better....
I ran some shot strings, more on that later, but here is what all you Geeks will be interested in.... This is a comparison of the efficiency in FPE/CI between the two valves.... Both sets of tests were done at 2400 psi....
A few important things to note here....
1. The PEEK valve has a larger throat and ports, so at the same pressure we would expect a slight improvement in power (which we got)....
2. Slightly different bullets were used, although both were sized so there should be little difference in bore drag....
3. The larger throat means about 1 turn more preload is required with the PEEK valve, so the curves are shifted 1 turn to the left (and hence I didn't test at 7 turns out)....
4. The net result of the changes was an average increase of efficiency, particularly up on the velocity plateau.... Right on the "knee" of the power curve, which to me is the most interesting and important (ie at about 900 fps), the efficiency jumped from just under 0.80 FPE/CI to nearly 1.00 FPE/CI.... While some of that may be due to the larger ports, I feel that a significant part is due to the quicker opening of the PEEK valve....
I also ran some shot strings with the 52.7 gr bullets at various preload settings, and here are those results....
Roughly speaking the starting pressure drops about 200 psi for each turn out on the preload.... At coil bind, I got 5 shots averaging 106 FPE within a 5% ES at an efficiency of 0.96 FPE/CI.... At 2 turns out, it was 6 shots at 93 FPE and 1.08 FPE/CI.... and at 4 turns out it was 7 shots at 78 FPE with the same efficiency.... The best efficiency was 1.11 FPE/CI at 3 turns out, and the tune I want to explore more is around 1 turn out or slightly less.... It looks like I can get 5-6 shots at 100 FPE at 1.00 FPE/CI with a little fiddling around, so that will be my goal....
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
Motorhead
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Re: Test of PEEK as a high pressure valve material
«
Reply #64 on:
January 07, 2014, 01:02:22 AM »
Data and original testing within this thread
http://www.gatewaytoairguns.org/GTA/index.php?topic=56954.msg544350#msg544350
Been a spell with the holidays to get in much AG fiddling.
After doing a 44 shot Fun FT match on sunday finding my POI going south within rifles 10th shot ... ( Duh ... low air )
* Had topped off rifle just 2 days earlier figuring as had always been the case, we're good to go come match day
Lesson learned !!! ... never assume all is well when you are changing stuff around with your airguns !!
Well sure enough after sundays embarrassing fupaw ... chased down where the air went ?
Sure enough right out under the Peek poppet/seat. Wow that's a Bummer.
Was yet to narrow the sealing margin ( Poppet head diameter smaller ) ... so, in we went to do just that while getting creative on lapping in the valve poppet contact surface of valve body using a few tricks of spinning a fine stone & then cratex on a 1/8 mandril placed into stem hole. Then with stem exiting hammer side chucked in an electric drill had spun them to clean and polish seat surface able to get a near mirror bright seat surface.
Now that done it became very obvious seat was a LOT smoother than factory had machined. ( tooling lines/grooves )
With a known throat of .250", chucked up the Peek poppet in lathe, got run out within .0015" and took O.D. down from the factory poppets diameter specs of .340" ( Peek made to factory poppet specs also ) down to @ .300". Then with compound at @ 3* faced off the sealing surface giving it a slight back cut angle. This 3* placed the contact with seat right at the outer most diameter of poppet head. A slight debur and rounded edge gave a
"Potential"
total sealing margin of @ .050" or .025" per edge of the seats circumference.
*Now with poppets head at sealing surface having the 3* cut actually the seal surface was a knifes edge at poppet O.D.
Next we brought out the semi-chrome metal polish placing a small amount on Peek poppet head at O.D. seal edge.
Dropped poppet into valve having stem come out hammer end in typical fashion.
Again chucked up stem in an electric drill and while spinning at slow speed ( both directions ) pulled poppet down against seat, lifting & repeating a few times each direction as if lapping in a internal combustion engines valves.
After a few go's taking it out and inspecting seal margin wearing in that corner of the 3* cut, stopped when the seal width was at @ .015" on the Peek poppet head.
Cleaned up, spun poppet DRY on seat one more time to burnish the two seal surfaces one last time.
Assembled main air tube parts again noticing upon filling that valve NEVER leaked at low pressure ( Sub 500# ) where factory and original Peek poppet did leak until @ 500/800# were in tube .... So the attention to getting a baby butt smooth sealing surface and lapping/burnishing in the seat seems to have payed off
Finished assembling rifle again as before CHANGING NO SETTINGS before some testing.
The @ 896/900fps from previous set up was confirmed before tear down .... NOW with the narrowed seat margin shots over the chrony showed @ 932/935 fps.
So valve indeed is flowing better from less flow resistance ... OR is coming unseated easier due to the narrower sealing margin and dwell is running a tad longer now ?
Dialed hammer spring tension down near 1 turn settling velocity back to @ 910 where rifle shot best before this PEEK testing started
So now we wait and see if storage leaks happen ... shoot some chrony strings when having the time.
Been FuN
Scott
«
Last Edit: January 07, 2014, 02:12:02 AM by Motorhead
»
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rsterne
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Re: Test of PEEK as a high pressure valve material
«
Reply #65 on:
January 07, 2014, 01:09:15 AM »
My guess is unseating easier, leaving more residual hammer energy and momentum, adding to both lift and dwell.... Basically as if you increased the hammer strike....
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
Big Bore Bart
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Re: Test of PEEK as a high pressure valve material
«
Reply #66 on:
January 07, 2014, 01:26:46 AM »
Dang it!
Now I gotta get me some PEEK.
Looks like a trip to Sactown is in order.
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Oroville, CA
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Motorhead
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Re: Test of PEEK as a high pressure valve material
«
Reply #67 on:
January 17, 2014, 07:47:52 PM »
Update #3
Holding air now while stored
Seems the lapping and burnishing of Peek poppet into aluminum bodies seat area was the ticket
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csdilligaf
Shooter
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My peek valve body
«
Reply #68 on:
January 24, 2014, 10:53:05 AM »
This is my Peek valve body and titanium valve. I will get this one in and post somemore info on it soon. I've been over on another forum for years doing this stuff but will start posting here alot more.
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rsterne
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Re: Test of PEEK as a high pressure valve material
«
Reply #69 on:
January 24, 2014, 12:36:20 PM »
Beautiful workmanship !!!
I have a question, however.... Why would you use Titanium for the valve and then add all the mass of the reciprocating spring guide / seat?....
Also, how is the PEEK valve body retained in the gun against the end force of the air pressure, does it sit against a metal collar?....
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
csdilligaf
Shooter
Posts: 97
yes
Re: Test of PEEK as a high pressure valve material
«
Reply #70 on:
January 24, 2014, 01:49:45 PM »
I use Ti for the valve to keep the wieght down plus I am a Ti junky and do entire guns in Ti. The stem in front of the head is vented to outside atmosphere. Removing the area reduces the force to open. I lighten the hammer by 40%, use zero preload and .250" of travel with 900 psi and get 20 ftlbs.
And yes, the valve body is in the 7075 action sitting in a counterbore. The smaller diameter is in the thru hole to the hammer chamber and only the valve stem sticks out.
«
Last Edit: January 24, 2014, 01:52:09 PM by csdilligaf
»
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rsterne
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Re: Test of PEEK as a high pressure valve material
«
Reply #71 on:
January 24, 2014, 05:22:59 PM »
Clever design, I don't think I've ever seen a pressure balanced poppet valve before.... How do you find the valve self-regulates with basically only the spring for closing force, or is your gun regulated so that is not an issue?.... I guess you could always use different stem diameters front and rear to get some closing force for self-regulation?.... As you said, the area of the stem reduces the force to open (by the ratio of the areas between the stem and the seat), but if it is the same diameter as the rear stem, it essentially cancels all of the closing force (except the spring and any parasitic drag around the head)....
What caliber are you working with?.... I ask so I can understand the relative significance of 20 FPE at 900 psi....
And lastly, welcome to the "Geek Gate" and the GTA.... *grin*....
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
csdilligaf
Shooter
Posts: 97
yes
Re: Test of PEEK as a high pressure valve material
«
Reply #72 on:
January 24, 2014, 05:49:09 PM »
Yes, Its a regulated 20 ftlb HV class benchrest gun. Shot consistancy is out standing. 4-5 fps es. I will start a post on it in the near future as not to highjack this Peek valve body thread.
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San Diego CA
lloyd-ss
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Re: Test of PEEK as a high pressure valve material
«
Reply #73 on:
January 25, 2014, 12:49:50 AM »
Chip,
Welcome aboard ! I definitely want to see the details of this when you start up a new thread. But darn, I like that balanced .... can we call it a spool?.... design. So both ends of the valve stem are open to the atmosphere and you can adjust BOTH the opening and closing bias by changing the stem diameters. Darn, now i can get rid of those sledge hammers I needed to open the big bore valves, but major redesign.
Which Ti alloy do you use for the valve stem? Is the valve stem one piece all the way through. Is the stem at the spring end sealed with an o-ring up inside the knurled section?
Lots of questions, but what did you expect?
Thanks!
Lloyd
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Central Virginia
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SeanMP
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Re: Test of PEEK as a high pressure valve material
«
Reply #74 on:
January 25, 2014, 10:06:58 AM »
Welcome to the geek gate!
I really like your valve design. I can see many applications for for a pressure balanced vale
But in terms of efficiency I'm wondering if a pressure balanced design wouldn't be similar in result to using a very heavy hammer. ie a long sloping curve rather than a short peaky one.
In an unbalanced design the pressure accelerates the closing velocity as it approaches the seat. This is desirable because we don't want the valve dawdling in the ineffective flow area.
Am I correct in believing that a balanced design would rely on the counter spring force to close. And the spring force is a constant
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Land O Lakes Ontario
"NO DELIVERY PROMISED. TAKE YOUR WORK WHEN DONE OR TAKE IT ELSEWHERE.
IF YOU MUST KNOW WHEN I WILL BE THROUGH WITH YOUR WORK THE ANSWER IS NOW. TAKE YOUR WORK AWAY. I DON'T WANT IT. I HAVE NO WAY OF KNOWING WHEN I WILL BE THROUGH. I WORK ELEVEN HOURS A DAY. DAILY INTERRUPTIONS AVERAGE ONE AND ONE-HALF HOURS.
THERE IS BUT ONE OF ME. I'M HUMAN AND I'M TIRED. I REFUSE TO LONGER BE WORRIED BY PROMISES THAT CIRCUMSTANCES DO NOT ALLOW ME TO KEEP." Harry Pope
SeanMP
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Re: Test of PEEK as a high pressure valve material
«
Reply #75 on:
January 25, 2014, 10:23:09 AM »
On second thought I've just been struck by a "DOH" moment
Force will still be inversely proportional to flow rate/potential flow rate
So the force will increase as the valve approaches the seat
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Land O Lakes Ontario
"NO DELIVERY PROMISED. TAKE YOUR WORK WHEN DONE OR TAKE IT ELSEWHERE.
IF YOU MUST KNOW WHEN I WILL BE THROUGH WITH YOUR WORK THE ANSWER IS NOW. TAKE YOUR WORK AWAY. I DON'T WANT IT. I HAVE NO WAY OF KNOWING WHEN I WILL BE THROUGH. I WORK ELEVEN HOURS A DAY. DAILY INTERRUPTIONS AVERAGE ONE AND ONE-HALF HOURS.
THERE IS BUT ONE OF ME. I'M HUMAN AND I'M TIRED. I REFUSE TO LONGER BE WORRIED BY PROMISES THAT CIRCUMSTANCES DO NOT ALLOW ME TO KEEP." Harry Pope
lloyd-ss
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Re: Test of PEEK as a high pressure valve material
«
Reply #76 on:
January 25, 2014, 11:20:05 AM »
Sean,
I think you could also vary the diameters of the two stem ends that are exposed to the atmosphere, and thus vary the amount "closing assist" . Having a large valve stem exposed to the atmosphere on the high pressure side would reduce the closing assist and would also reduce the force required to open the valve. If you had a valve that had 300 pound of force on it when closed, and could cut that back to 200 pounds, that could make it much easier to open but still have plenty of assist for closing. Combine that with your peek valves, and moving the return spring on your favorite side, and that could really be exciting.
Lloyd
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Central Virginia
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csdilligaf
Shooter
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yes
Re: Test of PEEK as a high pressure valve material
«
Reply #77 on:
January 25, 2014, 12:06:43 PM »
You guys hit it on head. About five years ago I played with this design but had one flaw. I was trying to have the stem on the high pressure side the same diameter at the head and use the spring to be the only pressure on the seat with the spring on the far side of the oring. Not much luck. I just wanted to use a lighter hammer. Recently others have done it better by using a smaller stem to reduce the knock open force but still use the higher pressure to seat the vavle. FX I think is the best example. Not sure but I think they may have a shaft with a delrin head in the middle some how.
Edit. Started build thread in "Show off your Air Gun with Mods" section
«
Last Edit: January 25, 2014, 12:19:52 PM by csdilligaf
»
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rsterne
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Re: Test of PEEK as a high pressure valve material
«
Reply #78 on:
January 25, 2014, 02:57:17 PM »
Lloyd, to look at some actual numbers, if the stem is 1/8" and the seat is 1/4", in a conventional valve at 3000 psi we would have 37 lbs. closing force (based on stem area) but 147 lbs. opening force (based on seat area) plus maybe 7 lbs. (typical) for the spring in both cases.... If the forward stem was also 1/8", the closing force would be spring only (plus parasitic drag past the head), but the opening force would still be (147-37) = 110 lbs. plus the spring (eg. 75% of what it was originally).... Reducing the forward stem to a size smaller than the rear stem would leave some closing force in addition to the spring, but increase the opening force to a value above 75% of what it was without the forward stem at all....
I think the key to this working properly is partly the PEEK valve seat which takes VERY little energy to "crack" the valve, particularly at the 900 psi that Chip is operating at.... There would be VERY little seat compression, and the energy required to crack the valve is (Opening Force x Compression Distance / 2).... Therefore, in his design, MOST of the hammer energy/momentum is going into creating usuable lift and dwell, and so the important number is the closing force rather than the opening force....
Bob
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🇺🇦
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lloyd-ss
Bob and Lloyd
GTA Senior Contributor
Posts: 3567
Real Name: Lloyd
Re: Test of PEEK as a high pressure valve material
«
Reply #79 on:
January 25, 2014, 10:02:34 PM »
Bob,
You have to try some very different diameters for this to work properly. Take a look at my picture and the snippet of spreadsheet.
I am depicting a big bore valve that you have to wail the tar out of to get to open. This balanced valve might be the answer.
In the picture, the stems at either end are open to the atmosphere. The hammer hits at end A. The return spring could be wherever you want to put it, internal or external. The HPA is always in the valve between B and C, and it exhausts between A and B. The stems are necked down inside the valve for good flow, but only the diameters exposed to the atmosphere are relevant as far as the forces are concerned.
Looking at the balanced valve first, the cracking force (the force holding the valve shut) is the force on diameter B minus the force on diameter C. (Or maybe more correctly stated "the force missing form dia C").
After the balanced valve is open, the force trying to close it is the Force on diameter A minus the force on diameter C.
In my chart, I have depicted a very big valve with a .45" throat. For the balanced valve, you can adjust and bias the opening and closing forces to just about wherever you want them, including to the point where the valve won't work at all. But look at what I came up with : 100 pounds to crack, and 100 pounds closing force. The picture isn't exactly to scale, but WOW, I like that.
Comparing the same .45 throat in a conventional valve with a typical .16" dia stem, and a diameter C of zero, you have a cracking force of 477 pounds and a closing force of 60 pounds.
That is one major paradigm shift. Am I missing something?
A couple of technical obstacles to overcome:
1) Stem C has to always be sealed so that the HPA doesn't leak past it, but it must not bind or add an excessive amount of sticktion to the operation of the valve. I have dealt with that type of dynamic seal before, and it can be a pain to get right, just like in a regulator.
2) The stems would might have to be hollowed out to get their weight down to something reasonable. Probably not too difficult. And probably the reason for Chip's titanium.
3) Figuring out how to expose both stem ends to the atmosphere could be a challenge. It will be difficult in some guns, but if the valve is fed from the side, not a big deal.
I think we might have some real possibilities here!
Again, am I missing something? Isn't this just a standard solenoid spool valve?
Lloyd-ss
(the little cyan circles are dynamic seals or o-rings)
«
Last Edit: January 25, 2014, 10:06:01 PM by lloyd-ss
»
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Test of PEEK as a high pressure valve material