Your Ship Is Leaking!

[am77494]

@FoieGrasIsEvil

I’m thinking in terms of the corrosive nature of sea water versus most types of metal. Perhaps stainless steel?

Austenitic stainless steel (in layman’s terms - Stainless Steel) is a bad choice for environments containing chlorides like sea water. From Wikipedia - Certain austenitic stainless steels and aluminium alloys crack in the presence of chlorides, mild steel cracks in the presence of alkali (boiler cracking) and nitrates, copper alloys crack in ammoniacal solutions (season cracking). This limits the usefulness of austenitic stainless steel for containing water with higher than few ppm content of chlorides at temperatures above 50 °C.Stress corrosion cracking - Wikipedia

Copper - Nickel alloys (Monel is one) and Titanium are good choices for this application. Titanium may look expensive but when you do the cost analysis - i.e. how much weight of titanium is needed versus say Monel, the grade of titanium, the lifetime, replacement costs, etc., it wins in certain situations.

[Bill_Door]

316, 316L, 317 and 317L and 254 SMO stainless steels are austenitic grades that perform just fine in the presence of chlorides at the appropriate pH. I’ve used them pretty extensively in pulp mill bleach applications. Titanium is corrosion resistant, but work hardens and gets brittle and cracks under vibration.

[Xema]

@mlees

They can produce their own water, but I don’t know if they typically do.

Yes, they quite routinely do. Naval ships like to be able to remain at sea for extended periods, which certainly requires fresh water (for washing, cooking, drinking, and power plant make-up).

[minor7flat5]

@Xema

Yes, they quite routinely do. Naval ships like to be able to remain at sea for extended periods, which certainly requires fresh water (for washing, cooking, drinking, and power plant make-up).

I don’t think mlees had seen my post immediately above his/her post. Given that a Nimitz-class carrier has over a quarter million gallons per day (400k) distillation capacity, it is safe to assume they need it. Daily.

[mlees]

What I meant was I am not sure if, while tied up to a pier here in San Diego, a carrier is going to be running it’s de-sal plant. (In other words, it may be getting it’s water from ashore.)

As I said, pierside is a great time to scrape paint and perform maintenance.

Also, taking suction from the harbor may run the risk of sucking in a lot more than usual trash and weeds and stuff. Why put that stress on the system when you don’t have to?

But for GQ purposes, I can’t swear on a stack of bibles that carriers do or do not routinely run the de-sal plants in port.

[robby]

@mlees

What I meant was I am not sure if, while tied up to a pier here in San Diego, a carrier is going to be running it’s de-sal plant. (In other words, it may be getting it’s water from ashore.)

As I said, pierside is a great time to scrape paint and perform maintenance.

Also, taking suction from the harbor may run the risk of sucking in a lot more than usual trash and weeds and stuff. Why put that stress on the system when you don’t have to?

But for GQ purposes, I can’t swear on a stack of bibles that carriers do or do not routinely run the de-sal plants in port.

U.S. Navy ships do not run the desalination plants while tied up pierside. Instead, they simply connect up to the shore supply of potable water.

For one thing, harbors are absolutely filthy, with all kinds of pollutants in the water.

[Snnipe_70E]

@mlees

What I meant was I am not sure if, while tied up to a pier here in San Diego, a carrier is going to be running it’s de-sal plant. (In other words, it may be getting it’s water from ashore.)

As I said, pierside is a great time to scrape paint and perform maintenance.

Also, taking suction from the harbor may run the risk of sucking in a lot more than usual trash and weeds and stuff. Why put that stress on the system when you don’t have to?

But for GQ purposes, I can’t swear on a stack of bibles that carriers do or do not routinely run the de-sal plants in port.

A ship is not going to run it evaps for drinking water inport because of health risk. They may run the evaps for boiler water though.

[mlees]

@Snnipe_70E

A ship is not going to run it evaps for drinking water inport because of health risk. They may run the evaps for boiler water though.

@robby

U.S. Navy ships do not run the desalination plants while tied up pierside. Instead, they simply connect up to the shore supply of potable water.

For one thing, harbors are absolutely filthy, with all kinds of pollutants in the water.

Ok, thanks.

For some reason, I was timid about asserting something I wasn’t 100% sure of.

That won’t happen again.