A pressure switch is almost always preferable to a flow switch (far more robust). The pressure switch is often wired into the start circuit so that the motor will start when the start switch is pressed but it will not stay latched-on until there is pressure developed by the pump.
Concrete is a non-Newtonian fluid. It is vibrated to fluidize it. Pascal's law applies to Newtonian fluids. The behavior of non-Newtonian fluids can be very complex but the worst-case pressure developed can be calculated assuming Newtonian behavior. That is about all you need to know when...
The subject is very broad and complex, and so requires considerable time and energy to study and understand. Google "non-Newtonian fluids". start here: https://en.m.wikipedia.org/wiki/Non-Newtonian_fluid
Thixotropic materials are those that have a viscosity that changes with time under shear. Bingham plastics behave as solids (infinite viscosity) until the shear force exceeds a threshold. Then they start to flow like a fluid. Wet sand is a Bigham plastic. Quicksand is where the particles are...
Rat-holing is something that many of us are familiar with in silos and hoppers storing granular solids. It is not a term used to describe fluids, but it is understandable as an analogy. The proper term for this effect is Bingham plastic. A certain shear force is required to before a material...
"Fading" is a conclusion that has not yet been established. The observed splotches could also be due to corrosion leaving white deposits. This should be observable under a microscope. Does it appear silvery or white?
Zinc silicate cures by reaction with atmospheric moisture. So coating thickness, humidity, temperature, and cure time are important. I do not agree with those who state that zinc dust galvanically protects steel surfaces. This requires that there be electrical conductivity between the steel and...
If it is only for color coding then only a spot spray is needed. A small dabber applicator sponge would be more efficient. Powder coating or dip coating would be best for full coverage. With dip coating you could coat a whole basket of springs at one time so you don't have to handle individual...
You have basically built a tray drying oven using cross flow air. These are common, and they all have similar design. Your design, though, is unusual in that it is relatively long in the direction of airflow. The problem with that is that the trays at the inlet side will see different drying...
The tear drop shape is evidently to match two different hole patterns using two different bolt sizes. Such as a machine with two different motor options.
Your vacuum chamber can simply have a hinged lid and use the vacuum pressure to keep the lid closed. Any positive pressure in the chamber will just lift the lid.
The pressure build unit is a vaporizer. Liquid gravity-flows to the vaporizer and warm vapor flows back to the vapor space. When the vapor valve to the tank closes the vapor will push liquid out of the vaporizer, back to the tank, and pressure stops increasing. It can reach any pressure up to...
"The wire melted and caused an arc flash which destroyed the connections to the fuse holder on the line side."
That is very typical damage caused by a loose connection. The heater acts as a current limiting resistor for the arc that formed when the wire melted.
It is not clear whether your are using the air to power an educator for unloading, or you are pressurizing the tank car to unload it. I'm guessing the latter, as compressed air flow to an educator would not increase when the tank empties. You need to use a restrictive orifice in the air line...
Reading this thread has brought images to my mind of a mob of angry villagers carrying torches up the mountain to storm the castle of the mad scientist.
Increasing the length does increase the "springiness" of the bolts but it does not affect the strength of the bolts or the load on the bolts. Springiness is required to compensate for thermal expansion. I don't think making them longer should be a problem. Making them shorter might be a problem.
