Leaks in fire hoses in pneumatic press

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antoxasam
Posts: 44
Joined: Wed Jul 03, 2019 1:55 am
Location: Russia, Samara

Leaks in fire hoses in pneumatic press

Post by antoxasam »

Hello everyone. I have been reading this forum for about 2 years now and am slowly progressing in the process of creating my first pair of skis. First of all, I want to thank everyone who has shared information here. This is really a great thing :)
I have a question: the fire hoses in my press have small leaks. I pump a pressure of 3 bar(44 psi) into the fire hoses. After 20 minutes, the pressure drops to 2.8 bar(41 psi), after one hour to 2.4 bar(35 psi). I.e. 0.2 bar(3 psi) in 20 minutes. I am going to cure the epoxy at 82C(179 F) for 40 minutes at a pressure of 3(44 psi) to 2.6 bar(38 psi).
1) How critical is this pressure drop?
2) Is it possible to pump up pressure into fire hoses during pressure to maintain constant pressure?
3) Is it possible to cool in the press with a gradual decrease in pressure? For example, at 82 degrees he held for 40 minutes, then turned off the heaters and left them in the press for another hour with a gradual decrease in pressure due to leaks.
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Head Monkey
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Re: Leaks in fire hoses in pneumatic press

Post by Head Monkey »

Small leaks in the hoses are normal. What you should do is put a regulator between your air compressor and your hoses. Your air compressor should have a tank attached to it, and should normally be at a much higher PSI. The air compressor should also keep it's tank at a minimum PSI much higher than you need to press at. Set the regulator for your hoses to 44PSI and let the air compressor hold it steady. It will run as needed to keep its tank at the proper (higher) PSI, and your hoses will never fall below your set 44PSI.

Your hoses will leak a little more over time, so your compressor will recharge more often as they wear. Replace the hoses when your air compressor runs too often for your liking, or simple can't keep up.
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antoxasam
Posts: 44
Joined: Wed Jul 03, 2019 1:55 am
Location: Russia, Samara

Re: Leaks in fire hoses in pneumatic press

Post by antoxasam »

Head Monkey, thank you very much.
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