'>>2786877
do your own homework, zoomie';

'>>2786877
flow is just a layman's term for positive pressure';

'>>2786880
You may not believe it but even in industry there are guys who don't believe pumps create flow. I had an argument with my coworkers this morning and we were not able to come to terms. I am looking for additional support from /diy/ to back me up here. More argumentation tactics.';

'>>2786881
Learning the difference between heat and temperature was a game changer for sure.';

'>>2786877
They create pressure. Pressure without restriction creates flow.';

'>>2786881';

'>>2786877
>>2786884
It depends on the pump.
Ie. Positive displacement is characterized only by pressure. It doesnt really make flow primarily.
Velocity pumps are characterized by flow. It doesnt make pressure primarily. Yet in both cases when working they provide both through the resistance of the piping to achieve work. As such misnomers simply cause accidents, a pump should be looked at by power, then flow/pressure and where it sits on the perfomance curve.

When operations replaces a pump with something 10x the size that was once there because of such misnomers, those same idiots get an eyeful the first time it turns on. They might achieve their desired flow but last time it happened to my co workers they blew off the pressure guage across the plant floor with a warman velocity (centrifugal) pump, claiming it would never get to critical pressure hurr durr it dont even seal like a positive displacement huuurrrrr durrrrr.

Its best to look at pumps like an f1 or diesel transport engine. Both make power but very differently, and that power gets delivered that unique way so you may enjoy the best parts of the engine curves during operation. Thats why pumps are specifically sized on all three characteristics as close as possible for successful operation as well as max efficiencyw for the application and piping it will deal with.

Your buddies are idiots trying to confuse you and they should fuck right off. You should also fuck off with literally the oldest strawman industrial arguement in history, you fucking greenhorn. This is the equivalent of being sent to the store for blinker fluid and a copper magnet.';

'>>2786905
>Positive displacement is characterized only by pressure.
>Velocity pumps are characterized by flow. I

You have it backwards. A positive displacement pump displaces a definitive amount of volume per cycle. Try to restrict its output, and it will produce whatever pressure necessary to maintain that output, to the point that it may break things.

Dynamic pumps generate pressure, with flow increasing or decreasing based on how restricted the outlet is.

Both of these are subject to the non-idealities of reality, but you get the idea.';

'>>2786906
i dont have it backwards. you are agreeing with me.
pd= constant flow variable pressure
velocity pumps = constant pressure but variable flow
hence their characteristic curves respectively.

reality is pressure, flow, and resistance are a trifecta and work is still watts/hp.';

'>>2786919
>you are agreeing with me

>>2786905
>Positive displacement is characterized only by pressure. It doesnt really make flow primarily

>>2786919
>pd= constant flow variable pressure

>It doesnt really make flow primarily
>constant flow variable pressure';

'>>2786924
oh ok ur just dumb boomer. see pic. centrifugal is the opposite.

with pd u pick the flow by size and check where on the curve you are for pressure.';

'>>2786929
Your initial statement was literally, "It doesnt really make flow primarily."

I don't know how the fuck you expected anyone to interpret that in a manner completely opposite to its wording.';

'>>2786934
because flow and pressure are irrelevant to a pump. only power is relevant. once you learn that youll see how dumb this whole strawman is.';

'>>2786934
How the fuck do you think the wobble pump, (which is pos displacement) on a pressure washer works? Its in the kpsi but singke digit l/min. How the fuck does that not mean "doesnt make flow primarly"? You must be an esl student.';

'Flow is derived from pressure. All pumps make pressure to create flow.
Different design requirements may need different pumps. A pump supplying boiler feedwater needs to be able to pump water to as high as the critical point of water at 22MPa. While a pump pushing hydrogen gas might go as high as 60MPa but would break trying to pump water 10m high.';

'>a pump makes flow and restriction makes pressure
>a pump makes pressure and no restriction means flow
its all so tiresome';

'>>2786877
Depends on design.';

'>>2786877
You began on the false assumption that it is one or the other.
>>2786889
>>2786967
Not “without.” Restrictions can be vary from free to blocked.
>>2786952
I guess if we’re on this planet. Based understander.
>>2786877
>>2786884
Tomato tomato. It is as Ohms law, where pressure is voltage. Flow is current. Resistance is restrictions. You can’t have any without the others. One goes down while the other up.
>>2786929
>ref: picture on the internet.
Shit will explode if there’s no bypass or relief, therefore it is a bit of a cartoonish explanation for a single component of a system.

The rest of you need to find another place to spout opinions.';

'>>2786884
>gif not animated';

'>>2786877
yes';

'>>2786877
>>2786877
they create flow
fuck everyone else who says something else
t. actual engineer.';

'Pumps create pressure. Flow is a product of pressure.

Much like how an IC engine creates torque, and horsepower is a product of that torque.';

'To find out what is a product of what, all you have to do is determine what is able to exist without the other. In this case, pressure can be present without without flow being present. However flow cannot be present without pressure also being present. That pressure being the result of work done by a pump, or the effects of gravity, or even electrical charge.

A pump will work even if the fluid it's pumping has no where to go, it will just create pressure in the fluid at the outlet until the pressure becomes higher than the amount of work the pump is able to output. Flow will only exist IF that pressurized fluid is able to find somewhere to go. Which concludes that a pump creates pressure, and that pressure will result in flow if flow is possible.';

'>>2786980
When I said "without" I pretty clearly meant 100% restriction.';

'Why does every thread devolve into retards arguing with each other
>>2787073
This. Pressure is more of a real thing than flow. In refrigeration you have flow because on one side of the system you have positive pressure and on the other side you have negative pressure. It’s called a compressor and not a comflower for a reason';

'>>2787085
> Why does every thread devolve into retards arguing with each other
OP posted a paradoxical chicken egg question to troll retards and they are full power taking the bait. Posting clueless ‘explanations’ as to why it would be one or another.

Diy has gone to shit a bit but this pretty funny';

'>>2787199
This is bullshit. Everyone knows that all pumps create positive, metric pressure. There is no way they ever create imperial flow. Retards. I swear.';

'>>2786877
My clunching applies pressure to my liquid shit which then flows into your throat whose resistance turns flow into pressure.';

'>>2787074
Well I didn’t want to single anyone out.';

'>>2787203
I’m Australia, they create vacuum.';

'>>2786877
Pumps push
That is all';

'hvactards out themselves every time with their retarded ass ideas on how things work';

'Pumps generally create head that varies according to how much flow is moving through them. The information for a given pump is read from the pump curve for that pump.';

'>>2786877
>create flow
or
>create pressure
Depends on the pump and surrounding system. Some create (or define) a particular flow rate. Positive displacement pumps, for example. Some create pressure and the external system sets the flow rate. Old school, cam operated diaphram fuel pumps come to mind. Carb float valve sets the flow. Pump just provides pressure to feed fuel if and when the valve opens.';

'>>2786877
Both. They just input energy in the fluid. Then flow and pressure derive from boundary conditions (pump's characteristic curve, upstream and downstream conditions)';

'>>2786877
flow by creating a pressure difference
but i'd say a pressure difference first that results in a flow since you can have a pressure difference from a pump without flow
like another anon has brought up the voltage and current equivalent, you can have a voltage with 0 current when R is infinite
but do retards really argue about this? bernoulli vs newton that creates lift over an airfoil is similar but far less obvious';

'>>2786877
how deep do you want to go? fundamentally it's an energy distribution lowering entropy. increased energy in a closed system increases force. force over an area gives you pressure. pressure differential gives you flow. flow gives you sick rap skillz';

'>>2789062
entropy always increases';

'>>2786877
Both variables are fundamentally inseparable just like current and voltage. Because they're the same. Look up bond graphs';

'PUMPS ARE LIKE WIVES

THEY PUSH BUT DONT SUCK

fuckin nerds';

'>>2786877
>>2786884
its better to think about pumps as an energy transformation device regardless of how pretentious that sounds, lemme explain myself:
prime mover provides mechanical energy to pump elements (kinetic energy to impeller or piston), typically through direct contact this energy is transferred into the fluid as kinetic energy imparted on the fluid, depending on the pump type and system configuration a portion of that kinetic energy stays as is (flow) and the other gets converted into potential energy (static pressure or head) now this also works for peristaltic and other similar PDP or any pump that rely on a moving cavity but instead of the energy being imparted on the fluid directly its imparted into the cavity.
>>2786980
>>2787067
i think its a bit silly to say one causes the other because they are affected somewhat independently from each other, yes the total head is affected by velocity of fluid (Hv) but that is not actually flow rate, even if its a part of it, and conversely if we look at the equations of flow rate pressure doesn't play any part of it at all. it is better to use the electrical power analogy or mechanical power analogy as they are actually closer to reality and are much more powerful intuitively speaking than ohms law or ...
> muh one causes the other

>>2787074
well that doesn't really work, restriction will always exist google friction factor and friction head (Hf) and viscosity, resistant to flow is an inherent property of fluid systems.';

'>>2791114
>if we look at the equations of flow rate pressure doesn't play any part of it at all
do you mean absolute pressure or something because a pressure difference absolutely does';

'Let me tell you about this son of a bitch. It's a double reciprocating pump (that is to say, positive displacement) for high viscosity slurries. In theory, knowing what the volume of each cylinder is, one should be able to count the number of strokes it completed over a period of time and calculate the volume it sent. In reality, the volume pumped is always 70-90% of what that calculation says it should be. This is referred to as its efficiency factor, and it's a bitch because it's always changing. It varies depending on the head pressure that the pump is pumping against, the viscosity of the slurry, and the frequency of routine maintenance. There's so much that can affect the efficiency factor of a pump like this that there's no real way to predict what it will be except to look at previous performance and assume it will continue to perform that way. If I guess the efficiency fator incorrectly then some corporate know-nothing sees a discrepancy in reported performance metrics and I have to explain to them for the twentieth time what the efficiency factor is.
The moral of this story is that even the simplest pump you could devise on paper will not function the same way in the real world. This is why arguments over the principles of flow vs pressure are worthless, and you should all stfu and look at a pump curve.';

'>>2786938
>Its in the kpsi but singke digit l/min. How the fuck does that not mean "doesnt make flow primarly"?

Remove the restriction. How much pressure do you have now? What percentage of your initial 2000-4000psi number is that? What is the flow rate now? What percentage of your initial flow rate is that? Of those two relative numbers, which changed more?

Put another way: You can tell, by looking at a PD pump by itself, how much fluid it's going to try and move per cycle. You don't need to know anything else about the system it's hooked up to. Why the fuck would you say a pump primarily generates pressure when the answer to "how much pressure will it produce" is "it depends" and the answer to "how much flow does it produce" has a definite quantity? Vice versa for a dynamic pump.

Ignoring, of course, the non-idealities of reality that some others ITT are um ackshually-ing over.';

'pumps make water go whooosh!

if water hit me i say it has pressure.

if it doesnt hit me or is puny i say i need more pressure.

but i say it always have whoosh unless no power to pump.

if pump inside closed container(why are you stupid or something?) then no woosh unless closed container breaks(but you need jiggawatts for this to occur)';

'>>2786889
With no restriction there can be no pressure';

'>>2792558
Flow is always restricted by dynamic pressure';

'>>2786884
They create problems when you get chips into the oil reservoir.';

'>>2786877
Look up how an engine works and you'll see that they don't have any static parameters, everything affects each other. At most you can apply the law of conservation of energy and see where power goes.';

'any other refinery mechanics here? Looking for a good resources to help me fix all the different kinds of pumps. Don't even start me on turbines and multistage displacement compressors. This shit will take decades to get good at.';

'>>2789101
It increases overall, but it can decrease in punctually.';

'>>2786877
>Do pumps create flow or do they create pressure?

https://www.pumpsandsystems.com/characteristics-centrifugal-pumps#:~:text=When%20the%20liquid%20slows%20down,of%20the%20resistance%20to%20flow.

Resistance to flow creates pressure but absolutism is not a useful way to think about that so >>2792816 is wise.

>>2792820
Industrial mechanic in a past life. The manufacturer websites and literature (manuals, data sheets) are a goldmine. Far too many mechanics forget that the people who made the pumps in the first place know all about them and as such are a primary information source.

BTW I hoarded info on personal flash drives including using portable browsers on company boxes (sending myself bookmark backups now and then) because your knowledge is your value. "Fixing" anything is the easy part once you learn troubleshooting. Have exploded parts breakdowns for everything.';