Home · Maps · About
Home > SubChat

[ Post a New Response | Return to the Index ]

(1466724)

view threaded

Galvanic Corrosion

Posted by northshore on Fri Feb 23 18:21:36 2018

The recently "Mind The Gap" plates on LIRR cars at the doors is causing problems with door closures which is causing numerous delays.
The LIRR design engineers did not realize that galvanic action of the aluminum plates and the steel cars causes corrosion.

Post a New Response

(1466727)

view threaded

Re: Galvanic Corrosion

Posted by Joe V on Fri Feb 23 18:51:55 2018, in response to Galvanic Corrosion, posted by northshore on Fri Feb 23 18:21:36 2018.

I guess they forgot the aluminum/steel corrosion issue from the original double deckers, which were a combination of steel and aluminum, with electrolysis at the joints.

Post a New Response

(1466739)

view threaded

Re: Galvanic Corrosion

Posted by Dutchrailnut on Fri Feb 23 20:09:53 2018, in response to Galvanic Corrosion, posted by northshore on Fri Feb 23 18:21:36 2018.

stainless steel should not corrode the sill plates should have had a plastic or other insulating barrier to prevent the aluminum from corroding.

Post a New Response

(Sponsored)

iPhone 6 (4.7 Inch) Premium PU Leather Wallet Case - Red w/ Floral Interior - by Notch-It

(1466744)

view threaded

Re: Galvanic Corrosion

Posted by Steamdriven on Fri Feb 23 20:45:23 2018, in response to Re: Galvanic Corrosion, posted by Dutchrailnut on Fri Feb 23 20:09:53 2018.

such as hard anodize the aluminum and cover the wearing surface with, ehh, something such as stainless sheet.

Post a New Response

(1466762)

view threaded

Re: Galvanic Corrosion

Posted by jan k. lorenzen on Fri Feb 23 22:31:48 2018, in response to Galvanic Corrosion, posted by northshore on Fri Feb 23 18:21:36 2018.

Salty stuff dragged in from the platforms can cause this too. Usually engineers will put an insulating material between the two metals to help.

Post a New Response

(1466773)

view threaded

Re: Galvanic Corrosion

Posted by zac on Sat Feb 24 07:12:50 2018, in response to Galvanic Corrosion, posted by northshore on Fri Feb 23 18:21:36 2018.

Whenever you have two different metals in contact this can happen. Ask any plumber.

Post a New Response

(1466774)

view threaded

Re: Galvanic Corrosion

Posted by Dutchrailnut on Sat Feb 24 08:38:59 2018, in response to Re: Galvanic Corrosion, posted by zac on Sat Feb 24 07:12:50 2018.

what actually speeds up process 10 fold on rail cars is passengers stepping on sill plate with salt and calcium chloride on their shoes.

Post a New Response

(1466776)

view threaded

Re: Galvanic Corrosion

Posted by TransitChuckG on Sat Feb 24 09:10:59 2018, in response to Re: Galvanic Corrosion, posted by zac on Sat Feb 24 07:12:50 2018.

I was in the semi-trailer business for 23 years. They had aluminum side bottom rails and steel cross-members. When I started , they had the end clips on the cross-members painted with zinc chromate paint. After a while , we just taped the inside of the bottom rail with a clear , mylar tape and did not coat the crossmember end clips, this worked well. You learn fast about galvanic corrosion.

Galvanic series

Post a New Response

(1466778)

view threaded

Re: Galvanic Corrosion

Posted by pragmatist on Sat Feb 24 09:18:08 2018, in response to Re: Galvanic Corrosion, posted by Dutchrailnut on Sat Feb 24 08:38:59 2018.

Salty water and slush will usually bridge over anything used to electrically isolate the plate from the body. Ask anyone who keeps a boat in salt water about "sacrificial anodes" US Navy had a big problem on the Independence, a brand new LCS. Well known issue, but plans to address don't always work the way you think they will.

Post a New Response


[ Return to the Message Index ]