Cleaning
MEOX has developed its own unique patented washing system where air is oscillated into the water jet, also called cavitation cleaning.
We supply equipment for washing nets, tablecloths, hulls, rafts and several other special applications.
Cavitation cleaning is possible with both low and high pressure. On the net, Sintef has tested that even with 200 bar, this type of wash is far more efficient and gentle than washing with 80 bar conventional wash.
Others have tested that with a cavitation wash of 60-80 bar, you can wash the hull without separating copper waste from the bottom lubrication. The washing system is in principle gentle on everything as the jet consists of large amounts of air. With a combination of reduced pressure and little water, you can still wash clean and gently and reduce diesel consumption by up to 80% of normal high-pressure washing. We also have machines that collect dirt from washing.
See below for more details.
Cavitation cleaning
New and patented for cleaning rigs, with many times more effect.
Cavitation is for most people known for damages to propellers and pump housings. If you have ever seen a propeller completely eaten up by cavitation you know the power of it.
There are air bubbles that form on the propellor wings and then collapse which eats the metal. We are using the same idea for cleaning. We add air into the waterflow and transport the bubbles out to the net wall.
Here the air bubbles are doing most of the job by knocking off the growth on the nets.
Tests performed in a lab has shown that cleaning with cavitation results in many (typically 5-10) times greater effect than ordinary high pressure cleanings at the same pressure.
Air bubbles
Very gentle cleaning with air bubbles
Sintef has recently tested wear and tear during high pressure, low pressure and cavitation.
Quote from Sintef report:
…After 35 cleaning events, on average 82% and 90% of the Notorius A and Notorius 3 coating, respectively, were damaged (Figure 7). Low-pressure cleaning damaged on average up to 9% after a single cleaning event and up to 46% after 35 cleaning events. In contrast, a single cavitation cleaning event had no measurable effect on the coatings (average damage 0%, maximum 2%)…
This means, after 35 cleanings, with impregnation Notorius A:
- High pressure, 220 bar, 220L, 82% wear
- Low pressure, 80 bar, 120L, 46% wear (increases with more water)
- Cavitation cleaning 200 bar 2% wear
It was so majorly to cavitation cleaning that even we were surprised.
With a cleaning interval of 10 days 35 cleanings is enough for a whole year.
This is nothing when during the same period approx. 50% disappears without cleaning during the same period.
ASC requirement 4.7
Satisfies “Gentle cleaning” under ASC 4.7
The ASC states the following: In ASC, paragraph 4.7, about impregnated nets, note 91 states the following:
…Light cleaning of nets is allowed. Intent of the standard is that, for example, the high-pressure underwater washers could not be used on copper treated nets under this standard. …
If there are any cleaning methods covering the phrase ‘Light cleaning’ it’s cavitation cleaning, also see ‘wery gentle as cleaning is done using air bubbles’.
All tests by Sintef were ran with high pressures and cavitation.
Using our patented cleaning system we have cleaned many impregnated nets using low pressures (typically 80-100 bar) and cavitation during all of 2019.
This has proven it cleans well and is very gentle.
Very little water
We normally use nozzles with a size of 1,4 – 1,7 mm, and low pressures. This means you need very little water, i.e. you save a lot of energy on the water pump/smaller pump.
Using 1,4 nozzles and a pressure of 80 – 90 bar, we only need about 190 l of water. If you are going to clean using a nozzle of 2 mm or larger you would quickly need about 500 – 600 l.
This means you can clean using two rigs using a pump that provides 600 l.
This is very cost effective, space saving and makes a lot less noise.
Low pressures and small amounts of cleaning water ensures all other components involved in the cleaning like swivels etc. has a much longer life span.
Full ROV functionality
MEOX Lavado can be driven in every direction.
It has 10 propellers (Lavado) distributed over the whole rig that all can be controlled via two 3-axis joysticks on the controller. It has every ability in both the x, y and z axis.
The fantasy and experience of the operator are the only limitations
