first small issue with MCH6, hose
- Thread starter h90
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Pictures would be helpfull. If the fill connector is of European design, then the fill assembly valve is probably a dual function valve, but I would need to see it to know for sure.
Don't know what to tell you about the PMV right now. Maybe the tape needs to be replaced.
Craig
Don't know what to tell you about the PMV right now. Maybe the tape needs to be replaced.
Craig
Thanks Craig!
When you look here: Aerotecnica Coltri - Portable Compressors - MCH-6/EM
that is exactly what I have, also the DIN looks exactly like on the picture.
At 300 bar there is no way to rotate the DIN connector, not even Schwarzenegger in his best time could open that. There should be a bleed valve I think, but there is non because there is not PMV in the original setup, so you could open the condensate drain to depressurize it. But with the PMV the pressure keeps staying.
PMV-Valve
I could reduce the blow out to almost nothing by tightening the screws.
I filled the first cylinder to 300 bar without problems.
I made a run in (always some brake between so it can cool down): turning it 10 times per hand (specially because there is a small hose from the oil to the first stage and it was filled with oil when I filled the oil and I did not know how much oil went in the first stage).
5 min running without pressure: everything open
Closing everything but opening the PMV valve and let it run 2 min at 30 bar, 3 min at 50 bar, 3 min at 80 bar, start to fill with 100 bar PMV till they tank had 100 bar.
Took the second tank filled it to 140 bar. Blow 20 bar to the first tank (I have dual valve and a hose to connect the 2 tanks).
Filled to 180 bar. move 20 bar.
Fill from 160 to 200 bar reduce 20 bar
Fill from 180 to 240 bar, reduce 20 bar
Fill from 220 to 280, reduce 20 bar
Fill from 260 to 300 bar.
(15 liter cylinder).
At 300 bar it still run smooth and without any problem. Just as I have a hydraulic and pneumatic company, I have the hell of a respect from 300 bar air.
Temperature for everything approx. 25 Degree Celcius and relative dry air (aircondition).
No smoking: Almost everyone is smoking in the office, I banned that as I worry for CO contamination.
Does that make sense or does it sound silly??
When I saw that "fill hose" I busted out laughing. It was meant for you to close the bottle valve and completely empty the Filter tower to "bleed" the hose. I saw no valve or bleeder on the hose. Bad idea for filter life.
The reason I was laughing is that by installing the PMV, which acts like a check valve, you have effectively trapped pressure between the PMV and the bottle you filled. What ever pressure the PMV is set for is what is trapped in the hose. Any pressure above that set point will leak back when the tower valve is opened.
You are going to have to add a line valve and bleeder between the hose and the din connector.
Good idea about the smoking! I don't smoke, but both my older brothers did and it killed them.
Craig
The reason I was laughing is that by installing the PMV, which acts like a check valve, you have effectively trapped pressure between the PMV and the bottle you filled. What ever pressure the PMV is set for is what is trapped in the hose. Any pressure above that set point will leak back when the tower valve is opened.
You are going to have to add a line valve and bleeder between the hose and the din connector.
Good idea about the smoking! I don't smoke, but both my older brothers did and it killed them.
Craig
I got a chuckle out of that "fill hose" too. 
You'll need to either replace the end with a real fill end or, at the very least, add a line valve with a bleeder.
You'll need to either replace the end with a real fill end or, at the very least, add a line valve with a bleeder.
Craig: in my setup the PMV traps the full 300 bar in the hose:shocked2: not only the set pressure. With 100 bar in the hose you can open it with POP when it blows out the Oring. (I don't worry about the Oring, I have 400 pcs on stock
)I'll add a bleeder, hope I get it locally.
Don't want to start a smoking discussion here....I smoke again since 2 month
Within March I'll stop it again. Stopping it relative easy but after a couple of month there is "just one". Which usually ends in a full smoking again......bad habit....better drink than smoke.....
rcontrera
Contributor
Either invest in a new filler that has a shutoff and bleed (most compact) or a shutoff valve with bleed (less money). You will need a JIC inlet and outlet adapter for the valve to fit it in line. (pictures below).
Do not unscrew the DIN fitting under pressure. Even though you may have lots of O-rings to replace the lost ones, the pressure actually puts a tiny bit of "stretch" on the threads and eventually something is going to break.
Do not unscrew the DIN fitting under pressure. Even though you may have lots of O-rings to replace the lost ones, the pressure actually puts a tiny bit of "stretch" on the threads and eventually something is going to break.
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