Water Valve Lesson

[sleddriver]

Gate, Globe or Ball: It makes a difference!

Thirty two years ago my brother & I installed an in-ground sprinkler system. To isolate it, we installed a 1-1/4" ID gate valve. At the time I mistakenly thought it would allow the highest water flow. It stayed open 99% of the time because here the ground doesn't freeze and often we have to water even during the "Winter".

FF to a few months back when I notice very green grass around one sprinkler head...and wet ground. I close the big-gate, but water continues to drip. Finally I give it a good twist and the handle shoots loose, sprays me with water and the cut-off is across the yard! I quickly grab a squeeze clamp to force the handle/stem/gate back into place, stopping the leak.

This time I go with a PVC ball valve. (Gotta love a ball valve for high flow, low obstruction, no noise, permanent seal, only 90° between OFF and ON, etc.).

Result? The in-ground inpulse sprinklers have never sprayed farther! Instead of tick-tick-tick they go BANG-BANG-BANG-BANG. Rather amazing to watch. It's obvious they're getting more pressure and volume now than before.

Several years ago I got rid of the globe valve on the HW heater, replacing it with two metal ball valves. When I refitted the water softener, I installed new plumbing with ball valves and unions so I could easily by-pass it or remove it for service, without turning off the water to the whole house. Now I'm thinking I need to do the same for another high flow situation: The clothes washer.

Gotta love ball valves.....

 

[tom slick]

I agree. I install ball valves on everything too, including hose bibbs.

 

[sleddriver]

Originally Posted By: tom slick
I agree. I install ball valves on everything too, including hose bibbs.

Yep...I'd like to replace all my hose bibs with BV's as well. Problem is they're sweated in.

 

[Stelth]

Originally Posted By: sleddriver
Gate, Globe or Ball: It makes a difference!

Thirty two years ago my brother & I installed an in-ground sprinkler system. To isolate it, we installed a 1-1/4" ID gate valve. At the time I mistakenly thought it would allow the highest water flow. It stayed open 99% of the time because here the ground doesn't freeze and often we have to water even during the "Winter".

FF to a few months back when I notice very green grass around one sprinkler head...and wet ground. I close the big-gate, but water continues to drip. Finally I give it a good twist and the handle shoots loose, sprays me with water and the cut-off is across the yard! I quickly grab a squeeze clamp to force the handle/stem/gate back into place, stopping the leak.

This time I go with a PVC ball valve. (Gotta love a ball valve for high flow, low obstruction, no noise, permanent seal, only 90° between OFF and ON, etc.).

Result? The in-ground inpulse sprinklers have never sprayed farther! Instead of tick-tick-tick they go BANG-BANG-BANG-BANG. Rather amazing to watch. It's obvious they're getting more pressure and volume now than before.

Several years ago I got rid of the globe valve on the HW heater, replacing it with two metal ball valves. When I refitted the water softener, I installed new plumbing with ball valves and unions so I could easily by-pass it or remove it for service, without turning off the water to the whole house. Now I'm thinking I need to do the same for another high flow situation: The clothes washer.

Gotta love ball valves.....


32 years ago, you were probably right. Full-port ball valves were available, but most ball valves were reduced port. Gate valves were a lot more common then. Now, full-port ball valves are cheap, and for most applications, there's no reason to use anything else. Rising-stem and OS&Y gate valves still have their place, but not for residential uses. I have, however, seen non-rising stem gate valves that were 50+ years old that still work. Needless to say, they weren't made in China.

Globe valves are a different story. Globe valves aren't full-port, but the old heavy-duty ones were pretty stout. A few years ago, I shut off a couple of 3" globe valves in a K-mart that were over 50 years old. It took a little persuasion to get them moving, but then they were OK. They actually shut the water off, and I wasn't worried about turning them back on. The only globe valves that I know of that are in common use now are hose bibbs and angle stops. Cheap ball valves have taken over, and that's probably a good thing.

 

[expat]

One caution, you can turn a Ball Valve off too quickly.

I have a friend that has a BV faucet outside her house. Last year she was watering and decided to stop, she gave the BV a quick twist and the Water hammer (spike in water pressure) blew a pipe fitting inside the wall :-(

 

[JHZR2]

This finding is the construct of a junior-level lab experiment in fluid mechanics for engineers.

I don't use anything but ball valves personally.

 

[Vern_in_IL]

PVC ball valves are JUNK!! My Dad had two failures, they tend to leak after a few turns, both valves were on main lines. I recommend brass.


The old Globe valves are junk as well, they start to leak or if not exercised regularly, exposed to hard tap water, you will not be able to completely close them!

I've also had a few full flow ball valves that like to "stick" in the open position. Once you get them turning no problem, but they "stick" open.

 

[andyd]

I gave up on valves with washers because my water corrodes bibb screws to nothing in a decade. Nothing worse than a shut off that does not. When I installed a pump tank every major connection is protected by a ball valve. I can install a filter element in 5 minutes now.

 

[DBMaster]

I also like them as shut off valves under sinks and toilets, especially toilets. My water heater was installed originally with a gate valve. It wouldn't even come close to stopping water flow. I replaced it with a ball valve. Several times I have just added thread on ball valves to hose bibs. I did this to my washing machine supply lines. The washers disintegrate after a few years. As long as I don't touch the hose bib valves it all remains leak free and I can shut off water flow quickly and completely.

 

[sleddriver]

Originally Posted By: JHZR2
This finding is the construct of a junior-level lab experiment in fluid mechanics for engineers.
Yeah....fluid mechanics just wasn't required for the EE program. Neither was thermodynamics. I find both quite interesting actually.

 

[JHZR2]

Originally Posted By: sleddriver
Originally Posted By: JHZR2
This finding is the construct of a junior-level lab experiment in fluid mechanics for engineers.
Yeah....fluid mechanics just wasn't required for the EE program. Neither was thermodynamics. I find both quite interesting actually.


Ok so think of it as different inductors with different time constants and resistances. Different rise times (number of turns/slope from zero to full flow), and different pressure drops.

Flow and pressure is like current and voltage.

I love EE as a chemE the same way.

 

[expat]

Originally Posted By: JHZR2
Originally Posted By: sleddriver
Originally Posted By: JHZR2
This finding is the construct of a junior-level lab experiment in fluid mechanics for engineers.
Yeah....fluid mechanics just wasn't required for the EE program. Neither was thermodynamics. I find both quite interesting actually.


Ok so think of it as different inductors with different time constants and resistances. Different rise times (number of turns/slope from zero to full flow), and different pressure drops.

Flow and pressure is like current and voltage.

I love EE as a chemE the same way.


I just told her to turn the Boody thing slowly!

 

[sleddriver]

Originally Posted By: JHZR2
Originally Posted By: sleddriver
Originally Posted By: JHZR2
This finding is the construct of a junior-level lab experiment in fluid mechanics for engineers.
Yeah....fluid mechanics just wasn't required for the EE program. Neither was thermodynamics. I find both quite interesting actually.


Ok so think of it as different inductors with different time constants and resistances. Different rise times (number of turns/slope from zero to full flow), and different pressure drops.

Flow and pressure is like current and voltage.

I love EE as a chemE the same way.

Ha! I appreciate the gesture regarding EE-only-verbage! However, I'm not that type of EE, much less engineer. I find it refreshing to get into other areas and learn about them and use their language. So I listen for turbulence, imagine little swirls and vorticies around the sharp edges, causing cavitation and noise and backpressure. Very similar to aerodynamics, except the fluid is a lot less dense and compressible to boot!

Thanks for that though!

P.S. I've always found Chemistry equally fascinating. The Periodic Table is a true work of art & science.

 

[Papa Bear]

I was told a gate valve was for on/off applications and a globe valve was for volume modulation (regulating flow, part way on).

I would suspect you had a defective valve if the flow was restricted .. something was wrong.

 

[doitmyself]

Originally Posted By: Papa Bear
I was told a gate valve was for on/off applications and a globe valve was for volume modulation (regulating flow, part way on).

I would suspect you had a defective valve if the flow was restricted .. something was wrong.


I had the same thought, Papa Bear. If he saw an improvement from changing from a gate valve of proper size to a ball valve of proper size, the improvement wasn't because of the superior characteristics of a ball valve. It would be like removing incorrect Denso spark plugs and installing correct NGK spark plugs, then attributing the improvement to the brand change.

Ball valves are also not supposed be use for throttling purposes...in theory.

Also, I was taught that if you are not approaching the limits of your fluid system regarding pressure, velocity, volume, etc., then the difference in the very short restriction of a regular ball valve vs. a full flow ball valve are minimal.

Regardless, ball valves are awesome.

 

[sleddriver]

Originally Posted By: doitmyself
Originally Posted By: Papa Bear
I was told a gate valve was for on/off applications and a globe valve was for volume modulation (regulating flow, part way on).

I would suspect you had a defective valve if the flow was restricted .. something was wrong.


I had the same thought, Papa Bear. If he saw an improvement from changing from a gate valve of proper size to a ball valve of proper size, the improvement wasn't because of the superior characteristics of a ball valve. It would be like removing incorrect Denso spark plugs and installing correct NGK spark plugs, then attributing the improvement to the brand change.

Ball valves are also not supposed be use for throttling purposes...in theory.

Also, I was taught that if you are not approaching the limits of your fluid system regarding pressure, velocity, volume, etc., then the difference in the very short restriction of a regular ball valve vs. a full flow ball valve are minimal.

Regardless, ball valves are awesome.

Well the old brass gate valve is sitting on the bench. Perhaps I'll disassemble it sometime and have a look. I didn't bother to measure the ID of the PVC BV before installation as I needed to get it installed, let the glue set so I could water the grass. Therefore, I don't have any comparison numbers for you.

 

[JTK]

It's even uglier if that old corroded gate valve is your only city water isolation in your basement.. and the packing decides to no longer hold.

This recently happened to me, which required my local water authority to install a new curb shut-off since they couldn't find the 40yr/old original!

That sucker leaked in my basement for a day and a half thanks to all that.

Got a new ball valve, w/ bleed in it's place. The first thing the plumber told me is to open/close it SLOOOOOOW if/when I need to use it.