Chinese Compressors?

[SurfLung]

Chinese Compressors and Filters?
- First we saw the cheap, weird compressors that are intended for airguns but will pump up a 3000 psi scuba tank in about 3 days. Now I'm seeing some that look like single stage compressors that go up to 4500 psi and fill at 1.7 cfm (13.2 gal/min. All of the tubing and ports on the single cylinder has me wondering if there's more than one stage stacked on top of each other.

ChinaCompressorLoRez.jpg

- I'm also seeing supposedly high pressure filter towers selling for about $200 a pair... Where a brand new US Made filter tower is multiples of expense higher. Has anybody checked these things out? Are they approved by the DOT or some other certification process? They are supposedly rated for 30 Mpa which is translated to 4351 psi.

s-l500[2].jpg

[antique diver]

I have never seen one of those. Is it true that they pack the filters with rice?

[ScubaLawyer]

I have never seen one of those. Is it true that they pack the filters with rice?

Are chopsticks included? I hear the grains have to be packed horizontally to maximize gas surface contact.

[captain]

It looks like it has a duplex cylinder, different size pistons in one cylinder. The Ingersol-Rand model T30 has duplex pistons.

https://airsystems-llc.com/wp-content/u ... ressor.pdf

[SurfLung]

It looks like it has a duplex cylinder, different size pistons in one cylinder. The Ingersol-Rand model T30 has duplex pistons.

https://airsystems-llc.com/wp-content/u ... ressor.pdf

Yeah! That's what it looks like and I read further in the description that it is a 2-Stage compressor.

A couple of other interesting things in the description:
1. It's water cooled... You have to hook it up to a water source.
2. It looks like it would need a check valve and back pressure regulator... Instructions say to open a release valve before turning it off to avoid a "high pressure air backlash". I think the airguns it is meant to fill have an internal check valve.

This compressor is an interesting consideration because the specs compare somewhat to those of the Cornelius compressors... Lightweight, capable of running on 110 house current, fill rate 1.7 cfm. I guess I'm wondering if the plumbing, moisture condensation, and filteration were done right, would this make a suitable scuba compressor for divers on a budget?

https://www.ebay.com/itm/300BAR-30MPA-4 ... 0033.m2042

Here's a quote:
"Superimposed double-cylinder two-stage compression used by this product has the feature of large displacement, quick air inflation, which could be not only used for diving fire cylinder,..."

[Vintagediver]

Yeah Eben I also was wondering if these compressors would fill any of our needs. My Cornelius 130R1500 is 110V, with a fill rate of 1.6 cfm and I've been very satisfied with it. I can fill my Voit twin 50's from 300 psi to 2300psi in about 55 minutes, and for my needs I'm real pleased. I have it set up with the filtration / separator tower on a wagon in the garage, and when it's time to fill tanks all I do is wheel it out by the door, get my lawn chair, fill record clipboard, a cold beer and start filling tanks. Works for me and I have to admit that after having it for only 4 years I love the ability to fill my own tanks any time I want to, nor do I have drive for 40 minutes to my LDS in Traverse City. Now that I own a compressor and have a little experience under my belt I can honestly say that I wish I had bought one long before I did. One of the best investments ever made.

[captain]

Producing 3000 psi in only 2 stages generates a lot of heat. Maybe water cooling overcomes the issue but my concern if it is oil lubricated is contamination from oil decomposition at high temperature, not an issue to a paintball gun but could present problems to trying to get breathing air. Generally 2 stages are used up to about 500 psi, 3 stages above that to about 3000 psi and 4 stages above 3000.

[timbo]

The thing I always ask myself when I see something like this made in china stuf is how can they make
this for that price? Wil it be safe to use and how long will it last. I must admit I h don't have much confidence in stuf like this.
It's like chinese stainless steel,it is named stainles but it sure is not.

Tim

[DerekRalston]

They do offer a "100% MONEY BACK GUARANTEE" so you can "BUY WITH CONFIDENCE", if someone wants to be the test subject. In this case, the cost of the filter towers is a lot more than the compressor, and you can't send the towers back for a refund if it doesn't work. I really WISH that it could work, so I would have access to an affordable compressor. If somebody already had a filter tower and wanted to prove the viability of the compressor, I'd be all for listening to the results.

[antique diver]

Just my 2 psi worth, but I think a two stage pumping to 3000 psi and more is going to generate a lot of heat due to the high compression ratios. The more stages the lower the compression ratio of each stage, meaning less temperature increase at each stage. Also the tremendous cooling benefit of having long runs of tubing for cooling coils between each stage is not there. I think this was made more for short runs to fill the low volume of air gun cylinders. Not feeling warm and fuzzy about filling Scuba with this, but I am hoping to hear more on the subject.

[Bryan]

I am no where near as knowledgeable as Tom or Bill but I would love to see the results of an air sample test after it had been pumping 3000psi for 2hs...

Sent from my SM-J700T using Tapatalk

[captain]

From the instructions it doesn't have continuous water flow.

9. When it is used for inflating slightly larger container, the cooling water should be changed every 30 minutes, in this way, the cylinder
temperature could be better controlled.

[DerekRalston]

It is continuous flow, but the flow is supplied by a very small waterfall type pump. The water that you change is in the bucket where the pump sits in the bottom and recirculates water. Not terribly efficient, but cheap.

[Chris]

So, where do I buy one of those $200 filter towers. I bought all the valves and gauges a couple years ago to build a setup. My original thought was using hydraulic cylinders with pvc inserts for the filter media. But have never gotten around to it.

[SurfLung]

$200 plus $100 Shipping. Here's the link
https://www.ebay.com/itm/2-Air-Filter-3 ... 0033.m2042

$400 plus $38 shipping. A better idea, I think...
https://www.ebay.com/itm/Scuba-Paintbal ... SwsTVaq34U