Cryogenic Cleaning
Regular cleaning of electrical machines prevents harmful external pollution which can lead to failure and ultimately loss of production. Cleaning with croygenic projects particles of dry ice (-73°C) onto the coils. The cold temperature causes the deposits to retract and detach from their base, aided by kinetic energy supplied by air pressure. This method is used mainly for the :
- stators of medium-voltage alternators or motors
- poles of synchronous machines
Methodology
- feasibility study
- on-site inspection for organization of the work
- construction of a sealed enclosure to prevent the spread of contamination
- supply of croygenic ice in the form of a block of ice or ice pellets delivered to the site
- cleaning work carried out by a qualified winder
- minor repairs if necessary
- painting of the coil if necessary
- final measurements - testing (UCC high-voltage test, insulating strength, polarisation index)
- Monitoring of cleaning operations and preparation of a report
Specific skills
HYDRO Exploitation assigns this work to specialist winders who are fully conversant with the machines and their insulations, having had a great deal of experience with this type of work.
Client benefits
Clients who choose this service benefit from cleaning of a very high quality. In addition :
- they avoid the need for a long and fastidious cleaning operation (cleaning with rags)
- they benefit from an inspection of the machine coil carried out by a winder while cleaning is in progress
- they gain time during the repair of the machine, thereby reducing production downtime
- they benefit from a natural and non-polluting process
