Questions tagged [hydraulics]
Questions about the flow and use of fluids.
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Reduced flow rate due to Hydraulic effects
Can anybody help me with papers or studies on reduced flow rates when pumping fluid through multiple pipes in a network due to hydraulic effects compared to those achievable when operating ...
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Computing the velocity of water under reverse flow conditions from storm water drain
I am trying to compute the approximate velocity of water during reverse flow from the outfall location to the street through storm inlets. This is generally seen during what is commonly referred to as ...
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Compression ferrules for bicycle hydraulic brakes
Between working on my and my girlfriend's bikes, I've come across different style compression ferrules (aka sleeves/olives) used in the hydraulic brake systems and would like to know:
What is the ...
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Estimate cycle of the pump per day
I have a pump system that is on for 5 days. For the entire 5 days, there are 3 days that the pump system is able to complete on and off cycle.
I want to estimate the cycle of the pump (on/off) per day?...
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Estimating circular pipe flow velocity through a known elevation profile and known length with a known initial pressure and flow velocity
I have a known elevation profile spanning the length of my pipe (~600 meters). An elevation value is given for every five meters of pipe. At the beginning of the pipe, I have a known velocity (1.1 m/s)...
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Hydraulic system single-action and double-action
I am looking at purchasing a hydraulic cylinder and a 12volt DC pump and motor to go with it. The pump and motor state that it is a single action pump, the cylinder mentions that it is double action, ...
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What's the hydraulic loss of this overflow?
Consider the following image:
what we see is are upright pipes into a water vessel, upper end of the pipes above the max. water level. Water is pumped into the pipes from below. We need to consider ...
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Solenoid Valve Resistance
This is basic but will a DC solenoid have 0 Ohms impedance when energized? For example, a valve in the closed position with 24VDC applied to the solenoid. Don't inductors have zero impedance for ...
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What would prevent me from using this valve for water?
https://www.kingstonvalves.com/product/ksv25cr-stainless-steel-asme-soft-seat-safety-valve/
Looking to use this for water instead of air. I haven't seen a good reason not to as the physics of the ...
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How do centrifugal pumps connected in series increase head?
I've read that if you connect two identical centrifugal pumps one after another, the head of this system would be twice the head of a single pump. I have some difficulties understanding the processes ...
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Volume multiplying hydraulic pressure reduction unit?
I'm tying to figure out what something is called, assuming it exists at all. If I knew what to search for, I'm reasonably sure I could figure out which part would be suitable for the application, but ...
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Effect of pump suction lift on pump vibrations and motor current
Consider the case of an electric motor driving a centrifugal pump.
The pump is installed above the tank.
In Case-I, the tank is completely filled with water.
In Case-II, the tank is emptied and thus ...
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What are the Units of flow coefficient Cv? And relationship between flow coefficient Cv formulas of incompressible and compressible fluids
I tried to understand flow coefficent Cv of a valve. There are many similar discussions on the Internet, e.g.,
https://www.pneumatictips.com/what-is-the-flow-coefficient-cv/
There are two formulas for ...
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Would connecting a small hydraulic pump to a larger hydraulic motor result in force multiplication?
In a hydrostatic transmission system, hydraulic pumps drive hydraulic motors (basically a reverse pump).
If you were use a smaller hydraulic pump as an input and a bigger hydraulic motor as the ...
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Are there hydraulic torque converters that are specifically built to work like reduction gearboxes?
As far as I understood from this video, there are torque converters and fluid couplers (a hydraulic clutch), but certain types of torque converters kind of work by performing the two functions at ...
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Why did pressure decrease above the piston?
I can understand the pressure increase below,but why did pressure decrease above as more bricks were added?
Image source: https://www.youtube.com/watch?v=4REdJIW6-Kg
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How does the hydraulic valve system work in excavators?
There are many types of valves used in excavators. Two are important: the main valve and the pilot valve. Is the pilot valve is controlled by the operator and the main valve is controlled by the pilot ...
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How many pistons are used in Excavator Engine and how they coupled with pumps?
As I am examining the components of a Caterpillar 323D hydraulic excavator, I would like to inquire about the specifics of its diesel engine. Can you provide information on the number of pistons and ...
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Design a manifold block and calculation of pressure drop
How to calculate pressure drop inside a manifold block with different pipe sizes for one connection to another. Overall the manifold block maximum working pressure is 10 bar. Can anyone send me basic ...
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Pumped storage hydropower, how to power the pumps?
Regarding pumped storage hydropower,
In the case of some high altitude upper reservoir that feeds several turbines located at the bottom of a valley, where there's a lower reservoir too.
Assuming in ...
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Is there a way of find the ideal balance between pressure and fluid flow in a hydraulic system?
So, I have 72 hydraulic McKibben actuators with 30cm in length and 14cm in width under 400 kPa (or 4 bar) that lifts a 5 ton weight that I want to actuate in a third of a second (continuously, ...
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Recommended books for calculations in hydraulic and pneumatic systems
I'm starting to learn about hydraulic and pneumatic systems. Although I have some idea of the basics, I would to dive deeper into the field.
Are there any books on hydraulic or pneumatic systems, ...
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Can a compressor give the same discharge pressure even if suction pressure varies?
The task is to maintain compressor discharge pressure at 200 bars. The inlet pressure varies with time from 200 bars to 10 bars (emptying a compressed air tank and compressing to transfer it to ...
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Why would the compressor provide more pressure than necessary? Isn't the pressure determined by the resistance?
I clearly misunderstood something
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How to build a hydraulic standing desk?
I am trying to build a standing desk but I want it to be wireless (aka - no electricity needed).
My idea is:
have 4 hydraulic pistons that extend (from 60 cm (25in) to 120 cm (50in)).
They will be ...
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How to transfer high pressure hydrogen using flexible pipes?
The task is to transfer hydrogen (high pressure gas > 400 bars) from offshore platform to land. To do so we have to use flexible pipes but for high pressure and high flow rate I'm afraid we can't ...
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Do 6/3 proportional valves like this exist?
Like a directional valve but used to select either pair of supply and return. Could be done with two regular 5/3 valves, but it would be nice to use only a single valve. Does something like it exist?
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Input power unit for Heavy Duty spool hose
I'm trying to design a machine for spooling a hose at a mining application.
Considering all hose length, mass, spooling diameter and pump the peak torque would be of To = 10267 Nm.
It sounds a lot but ...
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Hydraulics sluice gates and hydraulic jumps
I was wondering if anyone has an understanding on hydraulic jumps and sluice gates?
Why can you only use the energy equation for before and after the sluice gate? Why not at two points after the ...
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How does high inlet head affect outlet head on a fixed speed centrifugal water pump
I am curious to know what happens to a fix speed centrifugal water pump's outlet head if the inlet head is already relatively high.
For example, say a pump is said to have a max head of 10m. If it is ...
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Any scientific research papers on electromagnetic active valves using variable viscosity electromagnetic fluids?
I know the title is quite a mouthful, but let me explain (also, I couldn't find anything on the subject, maybe because I'm using the wrong words).
I saw some time ago a video about a variable ...
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Do excavators use electronic joystick and solenoid valves for direction control?
I studying how flow control happens in excavators. I came to know that the low pressure pilot line is used to control the high pressure hydraulic flow control valve (pilot operated direction control ...
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Confusing terminology for "normally closed/open" - It means the opposite in electronics (relays) versus fluids (valves)
I'm an electrician and "normally open" / "normally closed" is well known to me. I recently started to also work on heating systems including the pneumatic system that controls some ...
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How to divide the water flow into pipes with equal flow each from a free surface?
From a free surface pond, I'd like to divide the outflow into two separate pipes and direct them in two different places. Each outflow has to be equal.
Do you have an idea ?
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How to calculate time it takes for a cylinder to extend, if the pressure is not constant and the pump flow rate varies by pressure?
I am analyzing a hydraulic system that extends a single-acting cylinder. Due to a mechanical linkage, the force that the cylinder needs to exert decreases as it extends (and subsequently the pressure ...
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Why excavators use Hydraulic motors for rolling or moving forward instead of diesel engine?
I am currently studying How excavators work? and came to know that "In excavators diesel engine is used to drive the hydraulic pump. The high pressure fluid from hydraulic pump is used to run the ...
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What kind of system should I use to move the toroids of my CVT transmission?
I have a CVT transmission, which consists of a metal belt and four circular toroid discs, that form two pulleys. I need to be able to move the two toroids further and closer together. This movement ...
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Are there hydraulic cylinders that provide thrust and at the same time transmit rotary motion from a motor to a generator?
I am searching for a practical factory-made hydraulic cylinder (actuator) that can provide an axial push of 140 kN against the shaft of the rotor of an electric generator and also transmit the 90 kNm ...
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Are two forces required to cause shearing?
If we have a fluid, is one force acting along the surface of it enough to cause sheering? In most diagrams I see for real Newtonian fluids they show two forces of equal magnitude along the top and ...
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Understanding continuity equation
The volume for an open tank is given:
<$V = L \cdot L \cdot h(t)+ h(t)^2 \cdot tan(\theta)$>
Where h is the volume of the liquid within the tank.
I want to calculate the change in height as a ...
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Is NJDOT's method of calculating friction losses correct?
I have been attempting to develop a spreadsheet to calculate the hydraulic grade line (HGL) of a pipe system generally using the criteria set forth by the New Jersey DOT (NJDOT). Their Roadway Design ...
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Are there hydraulically actuated pneumatic valves?
I am working on a hydraulic system that is powered by an air-hydraulic piston pump, the pump uses pneumatic pressure to drive a piston which then pressurizes the hydraulic system.
The system needs to ...
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How to determine of pumps required on a pipeline
I have a 14km long pipe with total head loss of 113m, transporting water at 40m3/h. How do I decide how many pumps I need? I understand headloss is 113m, but I still don't get how does this tells me ...
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Correct Hydraulic Symbol for Check Valve
I was looking in a few different hydraulic power textbooks for symbol information and I noticed that on of them referenced a check valve with this symbol:
Is this "full" block symbol ever ...
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PC based real time control system
I am newbie, and I want to update an existing control system, which works with a 486 PC with AD/DA card currently. Is it a good idea to find a solution with a windows 10 PC, and a USB AD/DA card? The ...
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How does this transmission valve "hydraulic computer" work?
I just came across this:
The claim is that it is a kind of analogue computer. But I don't see any moving parts. How does it work?
EDIT: If someone could draw lines on the diagram to illustrate, that ...
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Incompressible Fluid Flow in horizontal pipe segment which encounters tilted pipe segment - Continuity Equation
Say that we have water flowing horizontally in a pipe of constant diameter. The continuity equation for incompressible fluids, which is a statement of mass conservation, guarantees that the flow rate ...
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will a hydraulic gear pump be capable of the same pressure at all speeds?
I'm trying to build a hydraulic power unit with a 5 horsepower electric motor, gear pump and tank. The flow requirement for the system is 1.7 gallons per minute. The pressure requirement is 3000 psi. ...
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Hydraulic circuit part question [Blanking Cartridge]
There is a part in this circuit called a "Blanking Cartridge". Its symbol looks identical to a standard capacitor in electrics. I have no idea what this part does. It is connected in ...
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Calculate hydraulic cylinder and pump forces on backhoe
I have a field find mini backhoe from a shut down manufacturer. The product is a beaver Pro QT50 backhoe used for small tractors, atvs, and pick up trucks. Unfortunately, there's no documentation on ...
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