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kenbob
12-15-2006, 09:13 AM
I was wondering what type of washing equipment you all use on washing insulators on energized transmission lines. We currently have a Chance Insulator Washer (high pressure water) that you can no longer find parts for any more. We are contemplating purchasing one of the dry cleaning systems. Is there one out there that anyone has used that would allow us to wash on lines up to 345kV??

Thanks for your help.

FL DEL
12-22-2006, 05:08 PM
Where are you at , Alot of salt??? alot of mist alot of both ???

Bigheadnc
12-23-2006, 09:26 PM
Only one i seen in action was at a FPL substation. it was a high pressure washer. It is my understanding they have one now that "blows" a non - conductive dry chemical.Can anyone help out?

BigClive
12-24-2006, 03:31 PM
Sounds like a very unhealthy mix of airborne solvent and oil. :confused:

sarh99
12-25-2006, 02:10 PM
We have 2 rigs built and we use distiled water in the from the power plants

BigClive
12-25-2006, 04:08 PM
We have 2 rigs built and we use distiled water in the from the power plants

Are any precautions taken to prevent the distilled water becoming contaminated? It only takes a little bit of dirt to increase the conductivity dramatically.

thrasher
12-26-2006, 08:16 AM
The water washing systems I've seen, use a pulsed spray so there is not a continous water path back to the nozzle. But read the warning!!! The one I used said to not let the nozzle get closer than 3 feet so that one pulse of water couldn't bridge the gap.

BigClive
12-26-2006, 07:45 PM
I don't much fancy that! What if the device that pulsed the water failed in some manner and shot a continuous stream?

mscheuerer
12-27-2006, 04:54 PM
I'm thinking more of the ionized arc flashing cloud that will form and connect between a pulse and/or ground/phase in the event a mishap occurs. But I could be wrong.... Perhaps it's all in the chemical? The distilled water thingy just isn't sitting well with me...

mscheuerer
12-27-2006, 04:58 PM
Only one i seen in action was at a FPL substation. it was a high pressure washer. It is my understanding they have one now that "blows" a non - conductive dry chemical.Can anyone help out?

Look MA NO HANDS! - That looks like a foldable clamp/hot stick to me not a blow tube device. However I must say you do indeed put a lot of faith in dem booties your wearing let alone no gloves... Thanks for the PIC!

BigClive
12-27-2006, 10:06 PM
Look MA NO HANDS! - That looks like a foldable clamp/hot stick to me not a blow tube device. However I must say you do indeed put a lot of faith in dem booties your wearing let alone no gloves... Thanks for the PIC!

I think that pic was just bighead introducing himself.

BigClive
12-28-2006, 02:49 PM
but when you spray from 12' away you need 20,000 ohm-inch, and if you find that clean of water, you've probably found the fountain of youth.

There are specific ways to clean with water,eg, wind direction, and those insulators will talk to you, and you will see flames coming off the pole, the secret is to not stop spraying.....spray the fire out, and keep going intil they're clean.......

Dry cleaning is a live line procedure, and is non-invasive. You can put the blowstick 4" - 12" away from the insul. and spray away, makes the insul. look brand new with no posibility of a flashover.

Fountain of youth? Here in Scotland my Tap water has about 15ppm (parts per million) impurities and inherently has a high resistance until impurities get added. Maybe that's why I look so young. :p

The blazing cleaning sounds rather spectacular. Must be a bit of a crowd pleaser.

Don't get too cocky about dry cleaning a line live. I'm sure it would be easy to contaminate some of the dry cleaning solvents and make them partly conductive.

mscheuerer
12-28-2006, 06:58 PM
There is a big difference between wet washing and dry washing.

Wet washing is the most cost efficient method, but dry cleaning is most effective when cleaning contaminates that become highly conductive when wetted, such as bird crap.....or on contaminates that are difficult to remove with other cleaning methods, such as oil on insulators......or on heavily contaminated insulators that are at risk of flashing over using water.

In wet washing the water doesn't have to be distilled, it has to be clear and clean and have a min.resistance in ohms per in cube, min nozzle pressure, specific nozzle orifice diameter, and min stream length/distance. For example...4 - 21kv is min 400 psi, 550ohm-inch, 1/4" orifice, and a min spray distance of 8'..
230kv at 15' away needs 550ohm-inch, but when you spray from 12' away you need 20,000 ohm-inch, and if you find that clean of water, you've probably found the fountain of youth.
500kv at 20' needs 1050ohm-inch.....and we get that out of a firehydrant, about 2000ohm-inch.
There are specific ways to clean with water,eg, wind direction, and those insulators will talk to you, and you will see flames coming off the pole, the secret is to not stop spraying.....spray the fire out, and keep going intil they're clean.......

Dry cleaning is a live line procedure, and is non-invasive. You can put the blowstick 4" - 12" away from the insul. and spray away, makes the insul. look brand new with no posibility of a flashover.

Heck, screw the washing! - I would just love to see the metering device used to check and determine the OHM's reading in between the Jet Stream of a live washout! I'ts amazing they actually have numbers for this!?!?!? I'm curious, do they actually test this reading somehow before they start at whatever footage is required??? Maybe they zip tie two probes together on hotsticks and inject them into the stream about an inch apart or so and take a reading?

BigClive
12-28-2006, 09:54 PM
The dry cleaning doesn't use a "solvent". It uses a dry media, ground up almond shells or walnut shells that looks like flour. It's stored to stay dry, and as long as it is not clumpy, it's good. Been doing this for 15yrs on the 500kv and have yet to have any problem. It's a very safe way to clean insulators....I've been in this business for 35yrs, mostly Transmission, and if my confidence sounds cocky...then so be it.

Sorry, I wasn't particularly referring to you as being cocky. It was just a general observation that spraying any liquid onto live conductors at high potential is bound to have a few of those unexpected "surprises" at some time.

The walnut shells are used to clean runway lights too. They seem to have a unique soft and fine abrading action thet removed dirt without causing excessive damage to surfaces.

Bull Dog
12-28-2006, 10:28 PM
We use water to clean contaminates off insulators. The spray is set fine so to get air in the stream which is a insulator. Never had a problem with it right out of the fire truck. Did transmission voltages also with no problem at all. Have also used this method to put out pole fires with energized equipment. The important thing is to keep the spray fine so there is nothing following back to the hose and then to me. Mostly from a bucket and no one touching truck. Did spray 69kv from ground one time worked fine. The company dosen't have dry cleaning equipment so know nothing about that.