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I have faced a problem with my air bladder. I gradually increased the pressure in a fire hose but after the pressure reaches 60 psi appeared strange squeak. I left the hoses at night and in the morning they were less than one atmosphere. Later, I spotted a place where the air out and was upset. Because of the pressure fabric of hose beginning to come out of the mount. I did not expect this. What would you suggest in this case?


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The line on the last picture shows the place where fiber started to come out. This is the place where air blown out from under steel corners.
Has somebody faced such kind of problem?

Looks like not enough clamping force. Hose got pulled out and i assume ripped at the screw hole.

bull's-eye. but I twisted the bolts that there are forces.
And afterwards I found it strange.
The one more thing. These fire hoses are not elastic as in US they are rigid made of nylon thread and rubber from inside. May be it is the reason...

Use thicker L-profile (see below), grade 8 bolts and maybe silicone between L-profile and hose. I assume the nylon is quite slippery so the silicone or something similar will help against pullout. Nothing will move anymore (hopefully). And btw. use washers

Check if the L-profile warps when you screw it down, if so use thicker one or U-profile or massive flat steel or ...

I put silicone everywhere but anyway we see the result. Probably I will use thicker L-profile and use washers. Bolts are of 8.8 grade as fr as I remember.

Thank you for the advice!!

We use the same type of hose without troubles. Our L-profile looks even thinner than yours, but we have grade 8 bolts basically right next to each other with washers.

I dont know what is the problem, today I will use higher grade of bolts and will apply new corners. Still I dont understand, because I screwed bolts as tight as it was possible.

That's pretty high pressure. I press a fair bit lower than that. But you also might want to look at the sharpness of that L profile. That's a pretty sharp edge you got that hose squeezing against.
I cut some heavy pipe in half and welded the halves on the vertical faces of my clamps.
My angle (L profile) is only aluminium and my holes are about 80mm apart and I have no problems. I also have a hose twice that size. I don't think your issue is the tightness of your bolts.

I figured out that the possible reason was the presence of silicon between hose and corners. Possibly I put too much silicone to insulate holes for bolts. The fiber in central bolt hole torn. I think that after high pressure hose fiber got out.

I did firehose collection number of times. always problem under the air connector and never under the bolts. Never use L shape profile always flat stock 3/8 to half inch thick 1 to 2 inch wide. 4 to 5 bolts per each end. Never find need to use silicon or similar products.

Metal plates are also good variant. I thought about them but they seem to me way heavier then L profile.

motoman wrote:Metal plates are also good variant. I thought about them but they seem to me way heavier then L profile.

Yes. You are right. Look up moment of inertia for beam bending.

A lot of good advice for you here though. Generally, sealing surfaces you want to be clean, flat, and have a lot of clamping force. One other thought is maybe your hole locations are a little funky and you're forcing some wrinkles when you put all the bolts through. You got this though. Just slam funk it and itll work.

let me show you how my air bladder exploded.

I tried to solve previous problem by placing sandpaper in between L-profile and fire hose for better adhesion since the problem was in holes that stretched from the first time and allowed to air comes out.
This method was good for first two times but third time was the last one))