Good afternoon*

This is a question regarding Water Wells but the matter (casing corrosion caused by production Electrical Submersible Pump) should also be of interest in the oil Wells.
We decided to ask such a questions to corrosion Engineers after a useless search in the Web of this topic in the water Well sector.
All the discussions and articles we found are dealing with cogrrosion and damages suffered by the ESPs in Wells.

We are facing a fast corrosion problem (2-5 years) in high yield Water Wells.
The casing corrosion is clearly caused by the production ESP (400 HP)* or* said in another way* the pump is involved in this corrosion process; video camera shows always corroded casing in correspondence of pump installation depth* nothing above or below this depth; it is something that* surprisingly* seems to be a very uncommon case.

We have found in the web only one article correlating this type of oil Well casing corrosion with the stray current caused by a partially grounded ESP and one more paper regarding increasing casing temperature caused by eddy currents induced by the magnetic field of the pump motor; we believe there could be at least three more reasons for this phenomenon: 1) galvanic corrosion between the SS pump and J-55 Casing (if in contact each other)* 2) increased flow velocity will increase corrosion rate in pump motor-casing annulus and 3) perhaps pump vibrations (if in contact with casing).

Main data:
Pump SS-304* OD: 12 ½”* 400 HP
Pump depth: 990 ft
Production rate: 800 gpm
Casing 16”* API J-55* 75 lb/ft


Many thanks in advance for any contribution* suggestions and similar field cases* if any* on this topic.

Roberto Salvi