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What Valve types in Copper pipes

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EnergyProfessional

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Jan 20, 2010
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This may be a doublepost as no on responded in Valve forum.
For some of my projects I'm literally buying all the valves and so i got into more detail into very specific valve model numbers. My main goal is very long life and very little downtime.
i like to select equipment that also works on cold (condensation = rust!) pipes. I also like to add that our organisation owns the buildings and I'm also in charge of maintenance. So any "saving money now" will haunt me later. If my design breaks in 10 years, I still will be haunted down :)

For flanged ball valves I found these valves to be very good (SS and Teflon-coated ball, Epoxy-coated body).
I though for smaller sweated or threaded valves picking a bronze body valve with SS-ball would be the best choice. It turns out for small valves SS-balls are much less available, and much more expensive. So i wonder if my requirements are too high for my use?

Most of the valves we use are operated rarely. I can think of them being equipment isolation valves, bypass valves, or vales connecting to pressure-gauges and sensors. I'm not asking about control valves, which get operated very frequently.

My thinking is that SS-balls and bronze body would be good because:
- Corrosion prevention. I assume after not operating the valves for years, they are more likely to be stuck if they have balls that could corrode (i.e. chrome-plated brass ball). i have to add we typically are good with adding corrosion inhibitors and de-aerating.
- Frequent operation will wear out the chrome-plated brass ball, and make it leak. I know they have some Teflon etc. seat.

Most of our current ball vales most likely just have chrome-plated brass-balls and may often only be brass body. We don't really have many valve problems. But I rather specify something to a very high standard as just having to replace one valve will eat up all potential savings. Or am I over-thinking this?

What type of Valve material do you recommend for bypass, isolation and valves for Pressure sensors / gauges? Would most likely be 1/2" to 2.5" in copper pipe.
Isolation valves will experience frow all the time, bypass and PRessure-isolation valves will never really see flow if that makes a difference in choosing material.

for other piping equipment I use bronze or epoxy-coated steel since All our older Strainers etc. that are made of steel or cast only have terrible exterior corrosion problems. Especially in chilled and geothermal systems with condensation. If there is some interior corrosion (I can't see that) that also will create problems in the rust particles potentially clogging up equipment or strainers. So saving a little money on a cheaper valve may cost much more in maintenance and repair.
 
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I only specify stainless steel valves when the room type or system type dictates, and cold water is not a deciding factor. If this is a chilled water system, I don't see why bronze ball valves will not work for you. They ball seat is usually a nylon material, and should allow for easier closing after years of being ignored.

If condensation is a problem with your piping, insulate. There are lots of insulating materials out there and you can insulate the valve (make sure the valve stem is extended so that you can still shut the valve without removing the insulation). A properly insulated piece of equipment or pipe will not condense because the moist air will not get to the pipe. PROPERLY INSULATED. Any gaps, and condensate will form, and the insulation will accelerate rusting or corrosion. Clean all pipes and valves of any indication of rust or corrosion before insulating.
 
Ziggypump: thanks. I think I should have been more clear. My thinking was between brass and bronze body (not Stainless) and between chrome-plated brass ball and SS-ball. Typically I use bronze for the small strainers etc. So my gut tells me to use bronze valve bodies.
Where I was most unclear was the ball-material since SS-balls are relatively rare.

I inquired with manufacturers and explained the situation (fluid type, temps, pressure) for most of our projects... but their blanket statement was that bronze valves with SS balls are good valves. Well, I knew they were, I just didn't know if a less expensive option would be equally as good.

Anyway, time was short and I just ordered the valves with SS-balls and bronze body and will do so for the future to stay consistent with the larger valves that all have SS-balls.
 
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