Overhaul of 15 kW motor for Statoil
Start date: 24.8.2011
There are many factors that lead to wear of electric motors. One of the most influential factors is the weather conditions. Motors that are exposed to rough weather are more likely to be damaged by water and rust. Especially in places like Kollsnes which is located out by the ocean and is windy, the salty air can be a problem. Statoil has several motors on their plant that are mounted with the flange upwards. This makes it easy for water to intrude which results in the inside rusting.Karsten Moholt has repaired several motors from Kollsnes and made a custom sealing solution to keep the water from intruding again.
A motor that was overhauled in July/August 2011 was a 15 kW three phase motor. From experience it seems that this size motor has more problems with the weather than smaller ones. The fan and fan cover were damaged by rust and had to be replaced. The bearings were replaced, and the motor was painted with offshore paint. The motor was tested, and a vibration analysis was performed before it was sent back to the customer.
Motors that are not prepared for the conditions they are placed in, are a problem that Karsten Moholt sees often. Motors that are being placed in rough weather, where water intrusion has been a problem earlier, should be modified before use. It is a cheap insurance against something that could cause an expensive repair later.