Recent content by MJP

Yes the two analyzing videos are still there, I did change the video description to add the mistake and deleted the hydrotesting videos. And no I dont make any money from any of my videos. Have not been here so often and missed your question. Marko

Ok everyone get your stones ready! There may have been a freak one to million fault in the first 470bar test, a piece of O ring was in the pump when I serviced it today, it was in the port where pressure goes in to the gauge. It is a possibility that the O ring piece prevented full pressure...

Ok first of all credit where credit is due, (I hope I got it correct as English is not my native tongue. ) Ed said that he would send me new cylinders to replace the ones I destroyed during testing. And he is true to his words, the cylinders arrived couple of days ago. One set with conical...

It means that on that corner surface the safety margin is 0.79 and material at the surface is yielding. So it is a stress riser at the surface of the material, you can see it in the cutaway there is less stress under the surface but the surface is stretching and can be slowly developing a...

Finally had schedules working and got the cylinder parts analyzed. It is 2024 or equivalent alloy, so in composition should be what Ed says it is. Material composition, measured with Hitachi Vulcan material analyzer. I can't tell you the temper / aging characteristics. That would require...

Thanks Dave, Now I have a reference to work with. Marko

Appreciate the offer, I think it's going to be too difficult in this situation in the world. You didn't say what the material was so I can't make a proper simulation and need to guess the material before I get it analyzed. Marko

Ok fair enough I used a linear load case and not nonlinear as pressure vessels are not something I simulate every day. I can easily admit my mistake as this is not my area of expertise, but I know enough about materials and stress in the material to be concerned. But then to the ridiculous...

Every component in the system must be rated to the full reservoir pressure or a burst disk installed on the lower pressure parts, so that they can only see the rated pressure. As the plenum has no bust disk it should be treated as 300bar rated part. Marko

That gouge is very worrying also, it is already a failure point in the surface, a discontinuity in a surface is a point for a failure to start. I did not want to go that deep in to discussion about surface imperfections and potential failure. The subject is complicated enough already for...

Most manufacturers use tubing with threaded ends, it's the most common type. And easies to manufacture. Making a tubing from solid is kind of stupid. Just my point of view. Marko

I will see what i can do. But this is taking alot of time to reverse engineer the design for simulation. The gun at hand wont have any other pressure related parts left original than the valve block and buttock. I'm designing a completely new modular cylinder with threaded end plugs and a...

Oh my, drilled it first then turned the corner sharp when they already had a tool in there that could have turned a radius there. If QC is like this, what will the material deviations be like. Speechless. Marko

In deed it does, at worst you could be talking roughly a minute given how fast your machine is and how fast turret from tool to tool. But tens of seconds any case. And then we get to the original design with 118deg drill bottom. It looks better if the material is correct. But if not then...

Please don't... And now to the case, as I mentioned in the latest video, a simple design change would be sufficient to make the gun safer. I changed the bottom corner to 5mm radius and the highest stress point moves to the threaded portion of the cylinder that is not under pressure and wouldn't...