Water ingress to " ROTORK" electrical actuator

Whats the application of the gear box. The presents of water in inside a device comes from the possibility of two things. Seal failure and/or condensation.

Hello k2chan

As advised by ozzb above, explanation of gearbox installation and usage is needed for accurate diagnosis.

GENERAL:

Underwater Gearbox:

If the gearbox is fixed, and under water, it requires to have the water entries sealed.

The gearbox may then either be pressurised a small amount by gas pressure, to a degree needed to ensure water may never enter.

It is often not realised that over time, water may creep along and through shaft seals, but if a positive small pressure exists in the gearbox, the water entry is unlikely to happen.

Above water gearbox:

The problem is probably caused by condensation.

The gearbox needs to be able to have the internal contents "breathe" by having an internal vent to the outside atmosphere, to prevent water absorption via shaft seals or other entries.

This vent should be designed with an inverted U at the top, and fine gauze fitted to prevent insects entering - silica-gel breather may be fitted, and that is the best option, because all entering air is thus dried by the silica-gel. The silica-gel should have a visible sight glass, and the silica-gel should be the variety which colour changes as it absorbs moisture, so that early replacement with dried out silica-gel may take place regularly.

You must bear in mind that we have not seen your gearbox in the installed situation, so if you reply, with showing a picture or two, or explanation, it may be possible to assist you further.

Kind Regards....

Rotorks have several openings which if not correctly maintained can allow moisture to come in. Primarily the Rotork range is built for valve applications in the oil industry and are built with that in mind. There are numerous "O" rings around the openings and these need to be replaced as specified by the manufacturer. If the actuator is in use in an application that makes use of the Exd (Flameproof) capability the unit or units must be refurbished to the correct standards by an accredited workshop. There is a time limit in service before a major overhaul too, often 4 years.

Each juristiction will have standards and licencing that must be adhered to. In Australia AS3800 must be applied to overhaul when used in hazardous locations. The repair shop and workers must be accredited. Check your local juristiction.

In short these devices are not for shade tree mechanics to have a guess at, not even on CR4.

If the Rotork is in use in a non hazardous application, the repair shops will still be the best port of call, but the overhaul will be cheaper with the unit stamped not for use in hazardous locations.

Dear Emjay4119

As first we found the "ROTORK" motor operated A range actuator motor grounded, wanted to drain the lubrication oil from the gearbox and found that the lubrication oil was mixed with rain water.

After we decided to remove the complete unit and sent to vendor for overhaul repair, the service report stated that the water got in from the hollow output shaft due to detective seal (O Ring) located at the hand wheel side.Thank your information

Best Regards

kk chan

Thanks for the feedback.

If you get the full maintenance schedule there should be service guidelines for "O" ring replacement in the various applications.

http://www.rotork.com/

Try this one.