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water characteristics

water characteristics

water characteristics

(OP)
hi there

hope you are fine.
I am dealing with a puzzling situation and I'd need your kind help

Please, is there any literature or practical reference concerning the characteristcs of water that is utilized for copper plumbing systems ?

I mean, limits of
- ph
- Carbon
- calcium
- megnesium
- Mn
- zinc
- chloride
- nitrates
- sulphates
- nitrates
- SiO2
- hardness
- ...

The topic is avoiding possible corrosion topics.
I have been asked by I have no clue where to look.

If anybody could help I would be extremely grateful.

Many thanks !

RE: water characteristics

Start with CDA.org
After you read a couple dozen of the papers there I am sure that you will have some specific questions.
In general sulfur compounds, pH, temperature and ammonia based compounds are you biggest issues, along with flow velocity.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: water characteristics

(OP)
@ Mr. bimr
many thanks
please, is there a specific table where to look for specific values

@ Mr EdStainless
please, for CDA.org I find this
http://www.cda.org/
please would you be so kind to indicate me the organziation I should look for ?

Many thanks

RE: water characteristics

Use the copper.org address, I am behind the curve.

No single table, you need to learn how these factors interact.
That is the key.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: water characteristics

There are no specific values except for maybe pipe velocity.

Do you have a specific problem that you are addressing? Post your water analysis.

Aggressive pitting waters can be identified by chemical analysis and treated to bring their composition within acceptable limits. Characteristically, they have high total dissolved solids (t.d.s.) including sulfates and chlorides, a pH in the range of 7.2 to 7.8, a high content of carbon dioxide (CO 2) gas (over 10 parts per million, ppm), and the presence of dissolved oxygen (D.O.) gas.

A qualified water treatment professional can specify a treatment for any aggressive water to make it non-aggressive to plumbing materials. In general, this involves raising the pH and combining or eliminating the CO 2 gas. Sometimes simple aeration of the water (e.g., spraying in the open air) is treatment enough.

Pitting can also be caused or intensified by faulty workmanship which leaves excessive amounts of residual aggressive flux inside the tube after installation. If the joints have been overheated during installation and the excess residual flux has polymerized, the pitting problem can worsen.

Soft acidic waters can cause the annoying problem of green staining of fixtures or "green water." Raising the pH of such waters to a value of about 7.2 or more usually solves the problem, but a qualified water treatment professional should be consulted. A typical treatment for an individual well water supply is to have the water flow through a bed of marble or limestone chips.

Excessive water velocity causes erosion-corrosion or impingement attack in plumbing systems. As explained in the discussion of pressure system sizing beginning on page 10, to avoid erosion-corrosion (and noise) problems, the water velocity in a plumbing system should not exceed 5 to 8 feet per second-the lower limit applying to smaller tube sizes.

Velocity effects can be aggravated if the water is chemically aggressive due to pH or gas content as outlined above, or if solids (silt) are entrained in the flow. The combination of a velocity that is otherwise acceptable and a water chemistry that is somewhat aggressive can sometimes cause trouble that would not result from either factor by itself.

Erosion-corrosion can also be aggravated by faulty workmanship. For example, burrs left at cut tube ends can upset smooth water flow, cause localized turbulence and high flow velocities, resulting in erosion-corrosion.

Any metal pipe laid in cinders is subject to attack by the acid generated when sulfur compounds in the cinders combine with water. Under such circumstances, the tube should be isolated from the cinders with an inert moisture barrier, a wrapping of insulating tape, a coating of an asphaltum paint, or with some other approved material. With rare exception, natural soils do not attack copper.

Copper drainage tube rarely corrodes, except when misused or when errors have been made in designing or installing the drainage system. An improper horizontal slope can create a situation where corrosive solutions could lie in the tube and attack it. If hydrogen sulfide gas in large volume is allowed to vent back into the house drainage system, it can attack the tube.

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