Visit the armored diving suits section in the historical diving section to learn all about the pioneers of atmospheric diving suits.
We stated before that Eluhu Thompson deserves the title of " Godfather of mixed gas diving" He was the one that suggested to replace nitrogen with helium in 1919. In the years after that several more experiments took place like the dive of commercial diver Max Nohl to a depth of about 140 meters on heliox in 1937.
Soon after that Word war II started and fighting got more attention than diving experiments. In 1946 Jack Browne (the inventor of the Jack Brown full face mask) made a mixed gas dive to about 180 meters.
Also in the 1960-ies America played an important role in the development of mixed gas diving. There were many oil companies there that constantly needed divers to go deeper. In the experiments that followed saturation diving was developed.
In the 1930-ies Galeazzi manufactured a copy of the German Neufeldt and Kuhnke suit. Galeazzi modified the original design in several points. For instance, he applied a gimbal ring in the joint that reduced the total area of friction making the joint more mobile.
Life support is maintained by an oxygen rebreather and: the diver can see his feet ! Looking down and working turned out to bee much easier than in the Neufeldt and Kuhnke suit. Like with the earlier rigs this suit was only really suitable with two feet on the ground and not while dangling in open water.
Helium developments slowed the design of new atmospheric diving suits but since helium was a scarce gas, inventors kept investigating the possibilities.
Around 1965 an English firm called DHB became interested in Atmospheric Diving Suits. With government help they wanted to perfect the Peress Tritonia suit from 1930 that they encountered by coincidence and luck. After some tests with the old suit it became obvious that the joints had to be redesigned.
The test suit that was build got the name JIM after Jim Garrett who was the first diver to test the old Tritonia suit. Many test were carried out in tanks and in the open sea up to 150 meters.
JIM soon proved to be a fantastic device.
Around 1972 another company (Oceaneering International) showed interest in putting new energy in an armored diving suit idea. The firm knew that oil companies needed to go deeper and deeper and that saturation diving in these depths would be too expensive. After negotiations OE took over the JIM's rights from DHB and improved it further.
Old JIM versions could go up to
500 meters and had 6 oil supported universal joints. The oil formed a perfect
watertight sea and ensured movability. The hands on the ends of the arms were
soon replaced with pinchers.
In case of an emergency this umbilical could be disconnected. Also the weights on the outside of JIM that assure negative buoyancy can be dropped by the diver so JIM will float to the surface.
JIM was engaged in numerous successful diving jobs, especially in the off shore oil business. Over the years modifications were made to JIM. The joints were replaced with others that allowed greater movability. The body is now made of fiberglass and the four portholes replaced with a massive dome. Depth limits now go to about 700 meters. This newer suit is known as JIM IV.
SAM is in fact a lightweight version of JIM. Aluminum versions can go up to 300 meters. Fiberglass ones can go as deep as 600 meters. SAM has JIM IV joints and oxygen supplies are carried externally.
In the 1970-ies some engineers wanted to develop a suit that had JIM possibilities but could also work in midwater. There was a need for this in the oil business.
It was designed by a former DHB employee and exploited by oceaneering international. WASP is a JIM without legs but with propellers and thrusters. It features two independent oxygen rebreather systems for life support.
As we said before, mixed gas and saturation developments stagnated the developments of atmospheric diving suits. These methods however are very expensive. In the seventies the oil companies did not have a problem with the high rates. Oil was booming business at that time and they were making a lot of money on it.
In the nineteen eighties the market shrunk and competition grew. Oil companies wanted more "value for money". For this reason designers were still interested in atmospheric diving suits.
In 1984 Phill Nuytten got a patent on an oil filled rotary joint. The joint uses oil as the bearing surface and features very small knife edges that ride in a deformable plastic. The joint also features a free-floating central piston. As the pressure increases, the piston uses the bearing fluid to lift the knife edges. This prevents further embedment into the seal material. This unique design keeps the joint easily movable, even at great depth.
The nuit suit has 20 joints in 6 different sizes. The wrist joint is the smallest, the hip one the largest. Compared to the other suits like JIM the nuit suit conforms more closely to the human body increasing the divers mobility. Suit and joints are made of aluminum. Two separate oxygen rebreather systems support life for 40 hours.
The umbilical features the surface communication
system. A wireless communication system is available for backup. The nuit suit
is the best atmospheric diving suit so far and has several advantages:
However, like its predecessors, it has some drawbacks also.
For instance, it can not work in extremely turbid waters. Dive jobs are nearly always performed in turbid waters. A diver often needs his "fingertip feeling" to work.
Besides this the smallest current makes it hard to work in the suit. It has a large surface and will catch a lot of water.
The nuit suit on his way to work. You can clearly see the thruster unit with propellers