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21

While pumping powders as a mix with swiftly moving gas is viable, one of frequently used alternatives for both powders and granular materials is Archimedes' Screw. Essentially, a helix in a diagonal pipe making the material "pour/roll" upwards the curve, allowing lifting it a long distance. This solution is frequently used in farming equipment for ...


14

With pumping diesel, your main constraint should be safety, not cost. There are very good reasons diesel pumps aren't for sale for $5 on amazon. The main things you want to look at are 1) whether the wetted materials are compatible with diesel (EDPM and silicone for example will dissolve) and 2) how it is grounded. Many pumps can build up static charge ...


11

You may also look into pneumatic conveying. It involves fluidization of the particles. This simply uses pressure differential to move any bulk material. It's used a lot in industrial applications. You can read a summary of those systems, here.


11

high pulse rate + low pressure means low pumping efficiency of the heart. this can be caused by: leaking valves, especially the main aortic valve, due to disease or calcification; low blood volume, due to bleedout as in bodily injury or an aneurysm rupture; incomplete contraction of the heart muscle due to a breakage or damage in the nerves which carry the ...


9

The motor will spin much faster than it does normally when loaded by the pump moving water. This higher speed may wear out something much quicker than during normal operation. The system should be able to handle the higher speed for a few seconds, but most likely it was not designed to operate at that speed long term. The extra robustness probably wasn't ...


7

This phenomenon is known as cavitation for pumping liquids - i.e. for anything that can change phase. If you are pumping gas, then the scenario really does come from choked flow. Let's say you've got a compressor and you're running it as a vacuum pump to evacuate a tank - at some point the tank's pressure on the inside is so low, you can't pump any more ...


7

The problem is that the airspeed drops as soon as the airflow leaves the nozzle. It is not the same as a water-jet expelling into air (in that case the density of the water is much greater than that of air so the water holds its velocity much better). The low-pressure air will suck in air from around it in the wider pipe and thus become turbulent around the ...


7

Even if you had matching orifices, you might have issues with the pressure drop inside the pipes and corners. If you are really after matching flow rates, you could look into flow control valves/flow regulator.


6

Head and pressure are effectively the same thing. It's impossible to look at a pump and say "this pump will provide 10 bar of pressure." One of my favorite aspects of fluids has always been how interconnected an entire fluid system is, and how it stabilizes itself on its own. So the pressure that's actually supplied depends on the rest of the system: the ...


6

Delivery is through a small nozzle that fills a slot behind the bar that leads into a hole in the bar which then leads to the chain. This slot is so that when adjusting the tightness and move the bar it will still deliver oil. The pump is driven by a worm gear which is coupled to the sprocket that drives the chain or directly to the drive shaft (depends on ...


6

You are correct, getting oil pressure will require an electric motor as your source of rotation, potentially a gear box to slow that rotation down, and the pump itself. You'll also need a reservoir to store the non-pressurized oil and probably a filter to keep the oil clean (dirty oil will damage your components.) If you're new to the world of hydraulics, ...


6

There is a key difference between liquids and powders: Liquids have internal cohesion and can be sucked, but with a powder, you need a carrying medium. The internal friction in a powder will usually be far higher than in a liquid. In practice, this means that to pump a powder, you inject air or another gas as fluidizing agent. The pumped or blown air ...


6

Think about the pressures. With the pump above the supply line, the pressure at the input of the pump will be lower than the supply. At roughly 2 PSI per foot, you're down about 18 PSI. Since air pressure is about 15 PSI, the system will at least work as long as the supply pressure is over 3 PSI, but that's still not a good situation. If the "supply" is ...


5

Looks like a typical water based central heating system (apart from the scale). You need to balance the flow by restricting flow for the units that get too much. This can be done by partially closing a valve or adding a restrictor for those units. Better if there is some kind of feedback loop to auto restrict when too much water is going through.


5

Despite the terminology differences I believe this is what you are looking for. http://www.treegator.com/ The ready-made pump is called gravity. The pressure of gravity pushes down on the closed bladder and exerts light pressure to the water that is higher than the pressure outside the pores. This small pressure differential pushes the water in the bladder ...


5

I have noticed that on the discharge port of the pump, a short row of bubbles comes out at high flows and low pressures. This does indeed sound like cavitation to me. Cavitation occurs usually in areas with a rapid change in pressure (from high to low, usually). As you say, when you increase the system pressure, the bubbles disappear. Think of it this ...


5

As well as 'proper' cavitation which is a fairly high energy phenomena and certainly a concern in terms of wear on the working surfaces of the pump it is possible that pressure changes are causing dissolved gasses in the water (most likely air) to come out of solution. The pressures and flow-rates here aren't huge but having said that gear pumps can ...


5

The terms you are looking for are "self priming pump" and/or "run dry pump". Centrifugal self priming pumps require some water to be in them to start, but can pull a vacuum including air. Diaphragm pumps pump air or water very well. They can run dry and are self priming. Some are specifically designed to just pump air. Vane pumps or any other positive ...


5

It is called a Regenerative Turbine Pump. It is lower efficiency than a staged centrifugal, but would fill the higher pressure single stage niche. Even though its max efficiency may be lower than a staged centrifiugal, it may be a good fit for your application. When considering efficiency, you should focus on the whole system not just the pump. Select a pump ...


4

I can't give a definite answer, since I hardly plan either type. So please read this answer as an incomplete list of questions you could ask the sales engineers of your pumps. Both can be operated hydraulically or pneumatically (for example if you don't want to bring a motor into an ex-zone or there would be cooling problems). In the case of piston pumps ...


4

The open flow is the flow rate through the pump where no pressure is developed. That is, if you have fluid coming in and out horizontally, and the input and output hoses are open to the outside air (not a closed system developing pressure. This is the most flow the pump will ever create. Usually though, we use pumps to either lift fluids vertically, or to ...


4

There are good answers here, but just wanted to clarify some points. It's important to consider what the liquid (in this case water) is used for in the pump. To begin with, it helps to see that the majority of pumps are made of two main components - an electric motor, and the actual pump (impeller and volute) itself. Starting with the pump itself, the ...


4

hm... I presume the term does not compress is what kicked of this question. Right? The task of a pump is to store energy in the fluid (potential energy in the form of pressure). This stored energy can be used for different purposes (e.g. @Fred comment). As you already mentioned there is a quite interesting feature of fluids. Some are compressible some ...


4

General rule when dealing with fluids The fluids will travel the path of least resistance. Treat them as dumb and lazy and you'll understand the process better; fluids will only travel where you make them and if you allow them to take a shorter path they will take it. 1 If the smaller pump puts less pressure than the third side orifice then the small pump ...


4

I did some internet searching and did not find anyone that had done a direct swap out. Granted, probably the majority of these replacements occurred before the existence of the internet ;-). As I am sure you are already aware (but to be thorough), modern diffusion pump designs do use synthetic working fluids. It will probably take some fine tuning of the ...


4

Pressure adds only a to the temperature of water. Pump pressure allows water to be moved, it is not used to maintain the temperature of the fluid being pumped. To minimize thermal loss of fluid in a pipe, the pipe need to be sufficiently insulated.


4

By necessity recommended speeds and feed rates are generalisations and, in practice the optimum for a given job can vary a lot. Recommended speeds are typically intended to be a reasonable compromise between material removal rate, quality of finish and tool life and it is entirely possible that in certain circumstances it is preferable to sacrifice one in ...


4

it has to be water for fire because its red. its on the out side so they can control the water without going into the building. the open pipe is to drain the water for maintenance. it does not have a meter on it so they are not paying for the flow of water.so for fire. all the valves are open. chains are so you cant open or close the valves. the electric ...


4

They are both correct. There are actually a number of different types of geothermal power plant with the most common being, dry steam, flash steam, and binary cycle. Dry steam plants require pumps to draw from underground resources of steam. This is piped directly from underground wells to the power plant. Flash steam plants (most common) use geothermal ...


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