Questions tagged [hydraulics]
Questions about the flow and use of fluids.
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What are the tradeoffs between using hydraulic motors and electric motors?
My limited understanding of hydraulic systems is that they aren't nearly as efficient as electrical systems, and that wire is cheaper than high pressure lines.
Example:
In a zero turn mower, each of ...
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What happens when pumps are blocked off?
What will be the result if the pipe losses is greater than head produced by the pump?
What will be the result if outlet is closed?
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What kind of pressure switch can I use for pressures up to 5-10 tons/cm^2?
I need a pressure switch for an electric circuit that has to be closed once a piston is compressing at a pressure of (approximately as we haven't specified how much force we have to use, and maybe it ...
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Can I make check valve in simple workshop?
I need a check valve ( one way valve ) for my project which has less actuation force (IDK real term. shouldn't require high pressure for inflow of fluid) and I searched in market for the valve but ...
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The use of Theis equation based on time
The storage coefficient (s) for artesian basin can be determined by the following equation (Theis equation):
$$s=\frac{Q}{4\pi T}\int_{\frac{r^2S}{4Tt}}^\infty\frac{e^{-u}}{u}du$$
Does this ...
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What (if any) are the engineering limitations for producing "simulation" exoskeletons
To clarify the title since it cannot be said within the word limit:
A "simulation" exoskeleton, is an exoskeleton that doesn't exist to support a disabled user's movement or to help someone carry ...
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Determination of delivery pressure from pump in my Parts Washer
We want to know how can we determine the pressure of the liquid at the delivery end of the pump. We have a centrifugal pump and a 2" pipeline at the delivery end. Pump delivery performance as per ...
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Motors, Horsepower, RPM and Litres per minute
How do I get a rough estimate of how many litres per minute a motor can push?
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Can Swagelok SS ferrule be reused?
At times, the Swagelok SS Ferrules gets crimped tight into the SS pipe. In those cases, can these ferrules be forcefully removed and reused?
Or was this a result of faulty installation?
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How Can I do punching of 0.22mm in stainless steel sheet (Sheet thickness 0.5mm)
Wanted to press punching of 0.22mm dia (Bottom) and on (top) 0.6mm dia
Please suggest how can I make such die?
user15441
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Fluid mechanics - how to calculate flow distribution in piping network?
I am trying to build flexible, visual tool to calculate flow distribution through the piping network (mobile hydraulics).
I have root node of the network which has defined flow and pressure inputs.
...
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Suppliers who write dynamical specification inside their data sheet?
I am a beginner in control system for hydraulic servo systems. The reason why I haven't started yet to do simulations of hydraulic servo system is because I have no information about the components I ...
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Water Valve Functionality
Before to present my question, I have to say that I'm not a hydraulic expert.
I'm working on a water valve design and I found this model which work with a diaphragm and a spring. I want to consider ...
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Need help identifying component on hydraulic schematic
I'm relatively new to hydraulics, and I'm trying to understand this schematic. I've got the majority of the system figured out, but I cant for the life of me understand what the symbols at positions ...
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Device to balance water pressure
I have a situation where I have two water supply lines and both need to be the same pressure. One of the lines is normally always a little higher than the other, but by different amounts depending on ...
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possibility for hydraulic accumulator with no moving parts?
Some background for context only
I am in the process of designing a pressure system where my pressurized fluid needs to be kept incredibly clean, with typical contaminants at the ppt or below level. ...
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hydraulic diameter
QUESTION:
I needed help here, I tried solving but still can't prove or arrive at the conclusion.
my working:
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Managing water supply pressure to a building
I am planning to supply drinking water only (not bath or sanitation or washing) from a tank on a 10-storey building.
The problem is that if a gravity feed is used, then the pressure will be ...
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Difference in flow measurements in an open channel
I'm undertaking a civil hydraulics question.
It involves the flow of water in an open channel down a river at $5m^3/s$ until the flow is split in two by a weir acting as a sluice gate allowing flow ...
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Calculating piston force for pneumatic vs hydraulic
I'm trying to calculate piston force pressures for double acting pistons for pneumatic and hydraulic pressures. I found the following formula for calculating both
$$\text{Force} = \frac{\text{...
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Why to avoid low and high fluid velocities in hydraulic systems
I know that different geometries of piping, orifices etc... have different critical Reynolds values. If the value is exceeded laminar stream will turn to a turbulent form which causes a variety of ...
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How do you get a closed vessel to >90,000 psi internal pressure
Im trying to build a cold isostatic press with a internal vessel area of 300mm3.
A cold isostatic press forms green metal components using pressures greater than 90,000 psi.
Using an oil or water/...
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Hydraulic Arm - Handbrake
I am researching a system that appears to have a hydraulic arm with some kind of "handbrake" as pictured below:
System Description:
Table that can raise and lock into place
Locking mechanism ...
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What material properties matter when selecting a material to withstand a specific pressure (as a sealed tank)?
I want to design a tank to hold liquid propane. The proposed tank would have one inlet valve, one output valve, and no sharp edges. I've read that the pressure required to maintain propane in a liquid ...
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Significance of the Sommerfeld number
The Sommerfeld number can be written as
$$ S = \frac{6 \ \mu \ U \ b}{p \ c^2} $$
where
U: Velocity
b: Width
p: Pressure
c: Minimal Clearing
$\mu$: Absolute Viscosity
As far as I'm aware, it may ...
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Hydraulic System design help/ directional valves
Default Hydraulic solenoid valve issue
I'm having a weird issue with some solenoid valves in a simple hydraulic circuit, let me try and describe the situation as best as I could.
Coming out of a 2 ...
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Why is pressure head ignored in open channel flow?
Also, what does this excerpt from Wikipedia mean
However, since with open channel flow, the water surface is open to the atmosphere, the pressure term between two points has the same value and is ...
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How can a car can be lifted using hydraulic press?(Pascal's Law)
The above pic is describing the system how the car will be lifted if car is placed on the larger piston. But if the small piston is moved through 1m (say) ,then the piston is merely moved by ...
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Darcy-Weisbach Equation
I've come across two forms of the Darcy-Weisbach Equation, and each one seems to yield a different result when I am solving for $Q$ (flow).
$$h_{f}=\frac{\lambda Lv^{2}}{2gD}$$
$$h_{f}=\frac{f LQ^{...
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Hydraulic pump choice - which produces most force
I have a choice of two hydraulic power units with specs as follows:
A. 2.2kW motor, 8lpm flow rate, 120 Bar pressure rating
B. 1.1kW motor, 2lpm flow rate, 200 Bar pressure rating
Using F=PA I ...
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Calculating discharge on the pipe diameter and the pressure?
Is it possible to сalculate discharge / flow rate on the pipe diameter and the pressure (for constant pressure)?
For example:
Pressure_internal = 5 bar, ...
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Boat Hull Drag in Shallow Water
I paddle several different types of small craft in the ocean and bays near my home. One phenomenon I've observed is beyond my understanding of drag on a narrow displacement hull. When paddling in ...
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Linear force multiplication (or division) without hydraulics
Gears are used to transfer power between two rotating shafts, either by increasing or decreasing the angular speed, with a corresponding inverse change in the torque. If I want to do the same for ...
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Water distribution - sizing weir buildings
I have a building to evenly split a water stream into two: Water flows into central chamber, over two weirs of equal height and length into two chambers and from there into pipelines. I'm looking for ...
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What is the difference (if any) in capacity factors and efficiency between reservoir hydropower and run-of-river power plants?
My question is about differences between reservoir-hydropower and run-of-river power plants. Are run-of-river plants less efficient? what would be an approximate guess of the differences? (assuming ...
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Some questions about liquid nitrogen cooling [closed]
I am currently tinkering with a railgun experiment, and I was thinking of using a liquid nitrogen loop to cool the rails down to very low resistance, and inject some nitrogen into the barrel between ...
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Does this exist - Water flow control with energy recovery
Classically, if you have free flow (high level to low, no pump) between two vessels you want to control you use some restricting orifice, or flow over a variable height weir. Both dissipate energy.
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Hydraulic Symbols
Hi all!,
I am currently working on a hydraulic project. One of the procedure requires me to setup a line as shown in the picture. I am fairly new to this field, I am not sure what does the symbol ...
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ABS Traction control / fiddle brakes
I have an 4x4 which I have heavily modified, the only thing missing is mechanical differential locks. I think it wouldn't be too hard to fit a four channel abs pump from another vehicle and produce my ...
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Reverse float shutoff valve
I have an application that is drawing fluid from a reservoir via a standard dip tube. This application has a special requirement that once the fluid is depleted from the reservoir, the pump pulling ...
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How do I recognize a good Hydraulic Servovalve? [closed]
How do I recognize a good Hydraulic Servovalve? It is probably the frequency response but what do I have to look for in these diagrams?
Is it correct to assume that the higher the frequency at a ...
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How to mount an O-ring differential pressure sensor in a pipe
I am trying to figure out the best way to connect an O-ring mounted differential pressure sensor into 1/8" female NPT. Ideally would like to do it with something like aluminum tubing, but I'm not sure ...
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Bedload discharge for canals of triangular cross-section
All the methods I know of for calculating bedload discharge are for canals of rectangular cross-section (constant depth of flow). The bedload is first computed for a unit of width (using the constant ...
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Where exactly will a hydraulic jump occur?
I know that an hydraulic jump can occur only when the Froude number is higher than 1 (supercritical flow), and I am familiar with the Bélanger equation. However, I feel like I have a fundamental ...
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How to calculate flow rate of water through a pipe?
If a water pipe is 15 mm diameter and the water pressure is 3 bar, assuming the pipe is open ended, is it possible to calculate the flow rate or water velocity in the pipe?
Most of the calculations I ...
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Why no hydraulic piston gas compressors?
I've been looking at solutions to compress gases and getting stunned by the cost and maintenance requirements of existing systems to fill cylinders (whether for SCBA or chemical storage) to 2000-...
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On a Diesel/hydraulic DMU train what exactly does the “go faster” lever control?
Let's say that you are driving a Diesel Multiple Unit† with either mechanical* (i.e. an actual gearbox with multiple ratios) or hydraulic (i.e. two or more torque converters) transmission. When you ...
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Help with hydraulic design
I made a waterfall hoping to use water as a piston for suction. I'm wondering if some of you could help explain why it's not working the way I was expecting.
This is the basic design: I have a 4 ...
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What options are available to create a vacuum with hydraulics? [closed]
What options are available to create a vacuum using hydraulics? I am working on constructing a small planter which needs a vacuum to operate.
Planters operate best at a pressure of 10 PSI. I ...
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How do I add a resistance to mechanical movement in both directions, apart from friction?
What options do I have for creating a resistance to a mechanical movement apart from simple friction?
Assume I have a lever, which will result in either circular or linear motion. I want to be able ...
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