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bjbarber
Anyone know how much head a spring check valve adds over a swing check valve? I need one going to my upper pond from a below water level filter pit. If I use a swing style, the plumbing will have to go from the pump, up a few feet then back down to the exit point. If I use a spring style, I think I can mount it horizontally, no?
wputnam
Swing check valves CAN be mounted either horizontal or vertical....
avorancher
My swing valves are mounted horizontally and they work fine. They have a mark on them that shows you which side should be on top (hinge side).
Steve Nguyen
I refuse to install check valves. I think it adds friction to the water flow then anything else.
Steve
boggen
spring check valves can vary a lot! so i doubt you will get a direct answer you are wanting. but majorty of the time they do require a good some of head loss to just to initally open the valve, then takes more to open the valve a little more, for more flow rate.
flapper check valves. or rather swing check valves. = no spring. and can open fairly easily with min head loss. compared to a regular fitting.
BruceP
Been there, done that. I installed a spring check valve on a circuit and couldnt figure out why I wasnt getting good flow..... til I changed it to a swing check valve..... problem solved. :D:
birdman
The flapper in the swing checks I use will actually swing completely out of the way allowing a un restricted flow. Here's a couple pictures of the 3" swing check.
koiman
Spring-type check valves are usually used on spa air blowers and swimming pool pumps. They usually use the 1/2lb valves. For our applications with our low head pumps, spring checks would be a NO-NO! Too much head loss to overcome.
If you're concerned about head loss from a check valve, increase the size of the valve from 2" to 3" within a 2" line. Simply add reducer bushings at both sides and connect to pipes. Oila! no head loss due to the check valve.
Mike
koibirddog
I would strongly advise against a spring check valve in a pond. String algae or other crud will build up on the spring and clog the valve. John
Steve Nguyen
Is there a real need/justification for check valve? so what if I open the pump to remove the leaves and other debris from the leaf trap basket and some water spill out. what's the real concern or justification to install a check valve? how often do people replace their pumps? if it's often, they have been using a wrong brand.
Steve
koiman
Is there a real need/justification for check valve? so what if I open the pump to remove the leaves and other debris from the leaf trap basket and some water spill out. what's the real concern or justification to install a check valve? how often do people replace their pumps? if it's often, they have been using a wrong brand.
Steve
Steve
Installing check valves is usually done on the intake line of the pump when installed above water level to keep the water from draining out of the leaf trap. Otherwise, you won't be able to prime the pump. Also, on the discharge side of the pump to keep water from backflowing from the filters. You can use ball valves on the discharge side for this purpose as well, but there is no difference in head loss for the two. If the pump is installed in a "flooded suction" location, then a ball valve could be installed rather than a knife valve. Of course, IF you like getting a bath when you open the lid to the leaf trap, none is necessary- -:eek1: :D:
Mike
Steve Nguyen
Mike,
ok. it's depends on situation. I haven't run into situation where I would need a check valve but I can see there is some benefits of having it. thanks for sharing your experiences.
Steve
koiman
No problemo, buddy!:D:
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kah
....in the category of "learn from somebody else' mistakes" - between clear and "white" check valves; those clear check valves do look pretty cool initially, but having them installed that they are exposed to direct sunlight makes them quickly less appealing looking (=GREEN) and leaky (because of growing algae inside). <= opening a leaf basked resulted in complete back flow.
How do I know this....dang, one of these days I'll have my brain engaged...
I wonder whether those "white ones" would survive any better, but one would think they would do better.
birdman
I just did an installation where the pump is above ground in a self priming configuration. Swing checks in and out. This way the owners don't have to worry about closing valves. just shut the pump down, clean the leaf basket, and fire the pump back up.
bjbarber
Thanks for all the input. I purchased a check valve alon with a bunch of other plumbing fittings last year from Lowe's when I had a discount card. I will be pumping from below water level in the main pond to an upper pond that will feed in from the bottom. So, by my way of thinking, if I turn off the pump, the 700 or so gallons of water will happily flow back thru the pump and into my filter pit without a check valve. I will return it and invest in a swing check valve.
As a seasoned hand in the fluid dynamics field, I&#;ve witnessed the elegance of simplicity in machinery. A swing check valve is such a device&#;modest yet indispensable. Picture this: a valve body hosting a hinged disc, and its only mission is to prevent the backflow of water. It&#;s like a silent guardian, ensuring the integrity of our pipelines&#;be it in your cozy suburban home or the vast networks of city infrastructure.The charm of a swing check valve lies in its passive nature. It swings open, allowing flow, then gracefully returns to a closed position when the fluid attempts to retreat. This ingeniously prevents any unwanted reverse flow which could, in simple terms, wreak havoc in the system. You see, the check valve, whether made of stalwart stainless steel or durable PVC, is a bulwark against disorder in our waterways.
To understand a swing check valve is to appreciate the harmony of physics and engineering. The hinge at the heart of it&#;no larger than the lever on your old backyard gate&#;holds the key to seamless operation. As flow moves through the valve body, the disc swings open, a motion as natural as a door responding to a breeze. And when the fluid flow ceases, gravity or a slight pressure drop ushers the disc back to its seat. It&#;s this simple action that guards against the dreaded water hammer effect, or reverse flow.
Cracking pressure, a term as rugged as the hands that install these valves, is the minimal upstream pressure needed to open the valve. It&#;s not unlike the first ray of sunlight nudging a flower to bloom&#;just a nudge, and the swing check springs to life, allowing flow. And when that pressure wanes, the valve closes as softly as the evening dims, ensuring that no backflow can occur.
Imagine a medieval portcullis&#;resolute and secure. The top-hinged swing check valve operates similarly. Mounted at the top, its disc swings upward, allowing fluids&#;be they as clear as mountain springs or as laden with grit as urban wastewater&#;to pass. When the flow stops, the disc descends, settling snugly against the valve seat ring as a guard resumes his post.
Now, envisage a balance scale, the kind that once measured gold or spices. The tilting disc valve functions on a similar principle. The disc tilts at a slight angle, reducing the pressure drop and the energy required to maintain flow. It&#;s the choice for systems where the equilibrium of pressure and flow is as precious as those ancient commodities.
The Y-pattern design takes a cue from the branching of a river. It offers a path of lesser resistance, making it suitable for situations where flow direction and minimal pressure drop are vital. It&#;s like choosing a well-worn hiking trail, ensuring the journey of the fluid is both efficient and undisturbed.
Let&#;s shift gears and chat about what swing check valves are made of. Picking the right stuff means the valve will work great and last a long time, even when going gets tough.
Here&#;s the lowdown on what&#;s what:
Let&#;s say you&#;ve got some acids like nitric acid or acetic acid playing in your system; stainless steel should be your number one draft pick. It keeps the valve disc in solid shape and makes sure the metal seat stays put for the long haul.As we roll into why swing check valves are awesome, remember that picking the right material is key. It&#;s all about making sure your valve can take on whatever the fluids throw at it without giving up.
Now that we&#;ve got the skinny on what these valves are made of, let&#;s dig into why they&#;re such a hot pick for folks who know their pipes and flows.
Think of a swing check valve as a reliable doorkeeper against backflow. When water or something else needs to flow, the valve&#;s flap swings open wide, letting stuff through in the right direction. But the minute the push eases off, that flap is right back where it started, quick and easy. This snap action keeps the pressure down and cuts the chances of a water hammer&#;that crazy inlet pressure spike that can make pipes dance and bang. Swing check valves are super responsive to pressure shifts, sealing things up tight so nothing sneaks back where it shouldn&#;t. Their hinge setup, with some added weight for better control, clamps down fast once the flow stops.
Let&#;s get real about how handy these valves are. Swing check valves are the quiet, tough guys&#;dependable with hardly any fuss over them. They&#;re super straightforward, which is why they&#;re so sturdy. Made to put up with the tough stuff like wastewater jobs and when the pressure cranks up, their anti-corrosion game is strong. They keep on trucking without needing fixes often, and when they do, it&#;s usually a breeze. They fit like a glove in all sorts of pipes, up, down, or sideways. Easy to put in and lasting a long time, swing check valves save you from too many repair headaches, making them a smart, budget-friendly pick to keep things flowing without a hitch.To give you a clearer picture, let&#;s lay out some specifics in table format:
Size RangeBody MaterialsTemperature RangePressure RatingsAdvantages2&#;-36&#;(50mm-900mm)Carbon Steel,Stainless Steel,Nickel Aluminum Bronze,alloy steel,etc-196 to 600 degreeClass 150 to Class ,PN 2.5 to PN420,10K-20KNon-return functionality, suitable for high-pressure systems, low maintenance, resistance to corrosion, long service lifeBefore we jump into the not-so-great points, keep in mind that no valve is the king of the hill. Each kind has its own hurdles, which we&#;ll check out next. But for folks looking for a valve that can take the heat and doesn&#;t ask for much, the swing check valve definitely deserves a thumbs up.
In every story, there is a cautionary note. The swing check valve, for all its merits, is prone to water hammer if not properly managed. Imagine a rapid closure in a high-velocity system&#;it&#;s like a clap of thunder following a lightning strike, potentially jarring enough to rattle the pipes.
While ensuring unidirectional flow is their strength, it&#;s also their limitation. In systems where reverse flow is required for operations, the swing check valve stands firm and unyielding in the forward direction&#;a guardian that sometimes needs to step aside for the greater good.
In the arteries of our cities&#;the water supply systems&#;swing check valves play a crucial role. They are the unsung heroes in the depths, ensuring that the water we drink, cook with, and bathe in maintains its course, free from the taint of backflow. In these systems, the valves must be robust, often made of stainless steel or brass, to withstand the pressure and the responsibility they bear.
Wastewater treatment is a testament to human ingenuity, and swing check valves are key players in this sector. They stand guard within the intricate maze of pipes, preventing the reverse flow of wastewater. It&#;s a dirty job, but these valves do it with the grace of sewage systems, ensuring that the refuse of our daily lives is carried away for treatment without once sullying the clean water on its way to our taps.
In the heart of industry, amidst the roar of machinery and the hiss of steam, swing check valves find their calling. They are the silent overseers of flow direction, crucial in processes where precision is not just a requirement but a creed. Whether it&#;s in power plants or refineries, these valves ensure that the flow of liquids remains uninterrupted, safeguarding the processes that fuel our modern lives.
Before the installation of a swing check valve, one must engage in a ritual as old as the industry itself&#;pre-installation checks. It&#;s a moment of quiet scrutiny, ensuring that the valve size and specifications align with the needs of the system. It&#;s about respecting the craft and acknowledging that even the smallest oversight could lead to a symphony of industrial dissonance.
The installation position of a swing check valve is a subject of much debate. Should it be horizontal or vertical? The truth lies in the application. Some systems demand a vertical position, others a horizontal guardian. The key is to understand the flow, the pressure, and the nature of the fluid&#;knowledge that comes with experience.
The installation of a swing check valve is a dance between the valve and the pipeline. It begins with the preparation of the site, a thorough cleaning of the piping, and the careful alignment of flanges. Then, with the precision of a seasoned artisan, the valve is introduced to its new home. Bolts are tightened&#;not too much, just enough&#;and then, the moment of truth: the system is tested, a silent prayer sent to the engineering gods.
In the realm of fluid dynamics, the swing check valve is a stalwart defender against the chaos of backflow. Its specific applications are as varied as the landscapes of this great nation, from the water supply systems that crisscross our cities to the industrial heartlands that pulse with the beat of progress. Its advantages are many, its limitations few, but with careful consideration and proper installation, it stands as a testament to human ingenuity&#;a marvel of simplicity and function.If you still have some questions, please feel free to contact Dombor.