Basic Tuberculation
________________ is a type of corrosion that develops in soft or acidic waters.
What is "Tuberculation"?
Basically, aggressive water penetrates the pin holes in a _____________ inner surface and internal corrosion in the form of tuberculation occurs.
What is "bituminous"?
CO2 and H2S both create ______ environments.
What is "acidic"?
Another way Oxygen influences internal corrosion is by oxidizing the ferrous ions that are in solution creating ______ Hydroxide.
What is "Ferric"?
Gas solubility __________ with decreasing temperature (colder water holds more oxygen).
What is "increases"?
Tuberculation affects the ________ diameter of the pipe.
What is "internal"?
The _______________ coefficient is also called a C value.
What is the "Hazen-Williams" coefficient?
Some dissolved gasses influence _______ rates of corrosion.
What is "higher"?
When Iron _______ two electrons, it turns it into an Iron ion (Iron II or Fe++) making it soluble (which means it dissolves in solution).
What is "donates"?
Gas solubility increases with ________ salinity.
What is "decreasing"?
Basically, _____________ penetrates the pin holes in a bituminous inner surface and internal corrosion in the form of tuberculation occurs.
What is "aggressive water"?
Early ________ in cement mortar lined pipes have maintained a C value of 130 (in some cases as early as 1922).
What are "C values"?
_______ combining with H2O (water) creates Carbonic Acid (H2CO3) which is a stronger acid than H2S.
What is "CO2"?
When Iron II is in solution, Hydroxyl ions which is 3OH- will react with it forming ___________ [Fe(OH)3].
What is "ferric hydroxide"?
Freshwater holds ______ oxygen than does saltwater.
What is "more"?
___________ mortar is the best lining of choice to fight tuberculation.
What is "Cement"?
Modern innovations in cement lining and high speed rotational ring-out process for ductile iron pipe have made the standard design value C of ______ a functionally conservative number.
What is "140"?
H2S does not combine with H2O like CO2 does which creates a _______ acid.
What is "weaker"?
Ferric Hydroxide is ___________, so it falls out of the liquid creating a deposit.
What is "insoluble"?
Gas solubility decreases as ________ decreases.
What is "pressure"?
Modern innovations in cement lining and high speed ______________ for ductile iron pipe have made the standard design value C of 140 a functionally conservative number.
What is "rotational ring-out process"?
Numerous flow tests in pipelines in the last 20 years have demonstrated in service performance C values of ____ and higher.
What is "150"?
The amount of _____________ that can be held by the water depends on the water temperature, salinity, and pressure.
What is "oxygen"?
______________ is when a deposit alone is not corrosive because there is not free hydrogen ions meaning the hydrogen is neutral.
What is "Under deposit corrosion"?
A deposit alone is not corrosive because there is not free hydrogen ions meaning the hydrogen is _________.
What is "neutral"?