Short question topic

[wyz2285]

Hum so the Long Range Barrel works..? Then that implies that the BB does ride on top of the barrel

[wyz2285]

Anyone have experience with booster pumps? My Yong Heng compressor does not fill passed 1000 psi even after I cleaned it inside out and remade the check valves. I suppose I can live with slower charging rate but do they last? The compressor cost me around 150 back in the day and the booster is 600 bucks! So it better work

[farcticox1]

If it is a piston pump does it have a piston seal/ring as well ? any wear there or the cylinder bore is going to lose pressure.

[Gippeto]

Anyone have experience with booster pumps? My Yong Heng compressor does not fill passed 1000 psi even after I cleaned it inside out and remade the check valves. I suppose I can live with slower charging rate but do they last? The compressor cost me around 150 back in the day and the booster is 600 bucks! So it better work

Built two, designed three. (gas boosters that is). Can help with those, but have never seen a Yong Heng "in person". Would suspect your Yong Heng has an issue with the second stage, parts are available from AliExpress to rebuild them.

Do you have any pictures of the check valves that you "remade" ? Checked the connections between stages for leaks? Crankcase vent is still venting?

[wyz2285]

Haven't opened all the check valves. The first stage pump uses a thin metal sheet as a check valve for intake, the first to second stage check valve was the first one getting damaged, it was a tiny brass cone with spring behind it, I replaced it with a one directing o-ring piston (So far the o-ring is intact, managed to reduce the dead space). Then I noticed the second stage output check valve wasn't sealing neither (steel cone with spring) so I replaced it with a nylon one, worked once then melted so I refinished the sealing face of the steel cone. Now I just found out there is another second stage check valve, need to open up. But so far the steel cone still isn't sealing...
Between this and this I'm seriously considering buying the first one. I don't mind the slow fill, since it's quieter and no need to the coolant system.

[Gippeto]

Wouldn't need a cooling system, but would need a supply of compressed air. Not a big deal if you already have an adequate shop air compressor.

As for replacing the Yong Heng, you could replace the entire top end with new parts for a fraction of the cost of either option you presented.

Are you just tired of it? Most folks on the airgun forums are having good success with them.

https://www.aliexpress.com/item/cylinde ... ed4bc46ce3

[wyz2285]

I already have a shop compressor so, not a problem.
The Yong Heng is loud, and it failed after maybe a dozen fills. Nothing promises the replacement top will be any better than the original. But I'll completely disassemble it today once more to inspect and give one more shot.
At this moment I just want a reliable way to refill paintball tanks...
Edit: After remaking the second stage output check valve, it managed to fill up to 3000 psi again without too much complain. The final check valve fitting is stuck for good so I can not clean/replace it but since it's working for now... I'm sure this thing is not going to last so, just temporary postpone my purchase.

[Gippeto]

A dozen fills is not much...did you contact the seller about warranty?

With the air compressor and the booster running, using the booster is not what I'd call "quiet" either.

Good luck with it.

Fellow actually starts the thing at 1:40...

[wyz2285]

My unit was old, way before Yong Heng was a thing yet. Doesn't have auto shut off and lack improvements compared to the new ones. It died again after two fills, probable same shit, I'm not gonna open it up so soon. It's louder than my shop compressor, needs messy coolant (I actually got a two fan car radiator with car coolant for it) and I need to be around because it does not have auto shut off. If I buy the new parts to update it the cost would be similar to just buy a new one and I'm not gonna risk with another useless compressor.
Booster pump waste some air to work tho right? Like a steam engine? Damn 6 hours...

[Gippeto]

Not sure what the actual air consumption for that booster will be, but it will be considerable, and the consumption will increase in relation to the output pressure.

It's a large diameter piston pushing on a smaller diameter piston..simple force multiplication. The one you're looking at is most likely double acting, two stage.

https://highpressuretech.com/products/g ... principle/

[farcticox1]

Whats the consumption ratio for boosters ? if you want 10 X pressure would you need at least 10 X the volume to achieve it ?

[Gippeto]

It's the ratio of surface areas that allow the pressure increase. The boosters I've built use a service brake chamber from a big truck as the driving end...that's a diaphragm with 30sqin. @ 100psi input from the compressor to that diaphragm it generates 3000lbs of force.

Apply that force to a 1" piston having an area of .785 in2 and you get a max outlet pressure of ~3822psi. Mechanical compression ratio also plays a role as to what the max pressure you can actually achieve.

I've never measured the air consumption of the ones I've built, but they have a 3" stroke, so if you assumed it was a pneumatic cylinder rather than a diaphragm, the chamber would have a volume of 90cuin. It takes 78.5psi to the diaphragm to generate 3000psi at the outlet, so 90 cuin @ 78.5psi per stroke.

I cycle manually, and use these to get 3000psi fills when my n2 tank falls below that in pressure. The pressure bleeds through the pump to the paintball tank or rifle...filling it to tank pressure before I start the booster. Having the booster allows me to use my tank until it gets down under 500psi...that's a lot of n2 I'd normally be returning un-used.

[wyz2285]

I know how it works, but for the pistons to return, part of the air will bleed out to waste while the Yong Heng supposedly uses all the air it pumps.
6h for 1,4l 4500 psi, so about 3 and half hours to charge my 0,8l to 3000 psi. I can leave with that.

[hectmarr]

What is approximately the ratio of piston areas of a hybrid, between the pilot area and the opposite side, which seals the combustion chamber? I would like to have an idea of your experiences.
I mean this, to the ratio of areas between "A" and "B"

[jackssmirkingrevenge]

As you drew it, assuming the piston is the same diameter as the chamber, you don't really want the piston to be smaller in diameter than 1.4 x A, because otherwise it will be choking flow. The bigger the piston, then the more dead space you will have. However, if you have the same pressure behind the piston, then the smaller diameter, the lower the pressure that it will "pop" at.

Let's say you have a 10x mix with a pre-ignition pressure of 150 psi, with the same pressure behind the piston. With B = 1.4 x A, then the piston will "pop" at around 295 psi. This is much less than the maximum pressure that a 10x mix can achieve. If the piston diameter B is 2 x A, that pop-off pressure increases to 600 psi, however there is a proportional increase in dead space.

For the best efficiency, you would want the piston that is around 150% the diameter of the chamber porting, but with a greater pressure behind it, say around 3 times the combustion chamber pressure.