How would you like to live in a 16 square meter pressurized tank for 28 days, with the world right outside and visible through thick, glass windows, but unreachable through inch-thick steel walls.
This is where and how divers live on the ship Mermaid Commander, the latest acquisition of Mermaid Maritime a company co-founded by Denmark’s Jørgen Lundbæk.
The ship’s arrival to Laem Chabang on Friday the 24th of March was the occasion for the amiable executive director to show us around an asset that is key to the company’s development in the offshore market working for the Mermaid subsidiary Mermaid Offshore Services. The Mermaid unit performs assignments such as checking and repairing underwater installations on ships or oil rigs, and the Danish-built support ship will be critical to such missions
Mermaid Offshore Services is the only company in Thailand approved to check maritime safety installations and their services are much sought after, one reason why they are currently expanding their six ship fleet with this new acquisition.
“We bought it last year and after a trip to the dry dock it just arrived here two days ago. It leaves immediately to do some work for American oil company Chevron as it is a very special ship built specifically to support saturation diving,” Jørgen Lundbæk explains.
To describe just what saturation diving is, it is perhaps easier to describe how the ship itself is built.
Its belly houses three rather big tanks – long chambers with steel walls several inches thick. The walls are thick as the cylinders are made to ensure that divers can live under the same pressure at their working depth after they return to the ship. Back on the ship, they are “trapped” in the cylinders where their food is served through an air lock and they breath a mix of helium and oxygen called Heliox.
Once a job is done deep under water, it will take the divers five to eight days to de-pressurize in the tanks. The three decompression tanks on the ship can house a total of 16 divers – teams of six or four in each tank. When the divers work, they do so in shifts, so only three of the six are ever inside the 16 square meter large (small) tank at a time. A normal work “week” for the saturation divers is 28 days.
Once it is time for the eight hour diving shift, three divers climb up through the top of the tanks into a small (little less than five square metre) diving bell atop the chamber.
The diving bell is then lowered into the water through a moon-pool (a hole cut in the deck of the ship) and once it reaches the work depth, two divers exit while the third remains in the small bell keeping an eye on the many dials inside.
The three chambers on the ship are connected by small tubes, through which the divers can crawl to visit the other chambers. One cylinder is a bit bigger than the others and has room for a table, which in any medical emergency, can be used as an operating table.
It the divers need to exit, a life boat is also attached which can house all the divers, while they de-pressurize – but it won’t be comfortable as the life raft for the 16 is only 11 square meters.
The Mermaid Commander is not a new ship, but built in 1987 in Denmark where it worked under a English firm before Mermaid bought it last year. The saturation diving system makes this a very special ship as few vessels have the same systems onboard. They enable the Commander to undertake diving assignments that can’t be done using normal surface diving.
And due to its special features, the Mermaid Commander is not going to spend much time in harbour.
“We have so many jobs booked in advance that we know what the ship is doing for at least the next two years,” Jørgen says.
The obvious question is that if there is so much work out there, why does Mermaid only have one ship like the Commander.
“They don’t exist! There is a sister ship and that is it! If we could buy one, we would have done so right away,” Jørgen explains.
There is always the option of having a ship purpose build, but that might prove to be too expensive.
“A new ship of that standard can easily cost US100 million dollars. To make such an investment we need to see what kind of money we could get back. And that is dependent on the oil prices which fluctuate way too much to risk such an investment.”
New member of the family
Aboard the ship Chief Officer Jim Wales takes a break to show the ship’s owner around.
“It is a good thing we are going out today. It has been too long already. We boarded the ship when it was still in dry dock,” he says not hiding the fact that he and the crew want some “action”.
The bridge of the ship is a mix of old style handles, joysticks and computer screens. The computers are used to make sure that the ship keeps floating over the same spot –a technique called dynamic positioning – which is essential when divers go down.
When the divers leave the pressure tanks on the ship and go to work, they are looking forward to an eight hour shift under water. Two hours to go up and down in the bell and six hours working. It takes a special kind of person to do such work.
“I don’t know how they can do it. I like the air and the sunshine!” Jim notes while looking inside one of the 16 square meter pressure chambers.
Jørgen nods in agreement. He remembers how it was when he and his partners started Mermaid Maritime.
“When we started we did all the work and diving ourselves. So I tried it. Not living in a bell though, but I tried staying still at the same depth for three hours in the water on our way up several times. Because you are decompressing you can’t change depth and it just gets very cold and miserable. Not a pleasant feeling.”
One thing does however compensate the divers. They are very well paid.
”The salaries are good. You get paid not only for the 28 days you spend inside the tanks – but also for the next 28 days resting until you go down again,” Jørgen explains.
Facts: Mermaid Commander (former CSO Marianos)
Length 91.1 meter
Width: 18 meter.
Accommodation: total of 80 beds.
Diving system: 16 man down to 300 meter depth
The ship can stay within a 0.5 meter square, controlled by GPS satellites.
Further on Mermaid Maritime:
Mermaid Maritime Takes Off