First article in Russian magazine was in
Спортсмен-подводник, issue 46, p.19
Created in our country scuba "Ukraine", "Ukraine-2", AVM, AVM-1M are autonomous respiratory devices with a margin compressed air and open circuit breathing. They are simple in design, reliable in operation, exclude the possibility caisson disease, nitrogen poisoning anesthesia However, these devices there are also significant drawbacks— short exposure time and high inspiratory resistance and exhale at maximum loads.
Air flow when working at depth 40 meters is so great that exposure time is reduced to 6 minutes.
The easiest way to increase stay under water - take with a larger supply of air. But for this you need to increase the number and capacity of cylinders Naturally all it makes the construction heavier its cumbersome. Besides the increase exposure entails the need more often do decompression stop when ascending and this negates all the tricks with increasing air reserve. That's why there was a need to create new types of scuba gear.
One of the new types of scuba the so-called hose apparatus is a construction in which air is compressed to 8 - 10 excess atmospheres, arrives at high capacity cylinder hose or from a compressor located on the surface, right into the respiratory automatic machine. When need a scuba diver can use emergency reserve air from cylinders attached behind the back. However, this combined the device is not without flaws.
Chief among them is the loss of a scuba diver autonomy.
Very convenient for working under water devices with closed and semi-closed breathing cycle and automatic composition regulation respiratory mix. Economical air they let you go down to great depths to pretty for a long time. Respiratory components mixtures can be stored in cylinders separately that allows adjust the composition depending on depth of immersion. However the design very similar devices complicated they are expensive to manufacture and so they can not yet find mass application.
More promising today is so-called cryogenic scuba gear developed by scientists and designers Kharkov Physical-Technical institute low
temperatures. Cryolang AK-3 received three copyright certificates for № 478489, 503152, 505141. At the Exhibition achievements of the national economy USSR machine received two silver and five bronze medals.
AK-3 is designed for various underwater technical, research, rescue and other works at a depth of 45 m. Has open breathing cycle, what is used for liquefied air or air-oxygen mixture maintained at a temperature of - 190 ° C Dewar vessels. Supply of respiratory fluid mix allows you to be under water about four times longer than using compressed of air. New single stage design respiratory machine allowed at a depth of 45 m (with breathing mix consumption 155 l / min) reduce inspiratory expiratory resistance up to 50 mm of water. Art.
The presence of two components of liquefied gases allows when charging devices depending on the set immersion depth and exposure time
make up the necessary gas mix so that step decompression mode turned out to be minimal. The mixture is made up by weighing oxygen
and nitrogen separately and further mixing them.
Technical specifications of Cryolung AK-3
Depth of immersion - 45 m.
Mass apparatus on the air:
filled respiratory mixture - 24 kg; without respiratory mixes - 16 kg.
Dimensions - 680X350X140 mm. The number of vessels - 2.
The mass of the breathing mix is 8 kg.
Stock respiratory mix - 6900 l. Stock reserve breathing mix - 500 l.
Safety factor on the outside double pressure - 9 kg / cm2
Stock strength to internal pressure three times - 25 kg / cm2
Installation pressure - 5.8 kg / cm2
Tripping safety valve - 10-15 kg / cm2
Positive buoyancy +1 kg.
Negative buoyancy - 2 kg.
Refueling time apparatus - 3 - 5 minutes.
Preparation time apparatus to work immediately after refueling - 8 - 10 min.
Preparation time apparatus to work pre refilled - 1-2 minutes
On the air can breathe from the apparatus no more - 10 min.
Thermal insulation vacuum vacuum screen - 10 -3 mm Hg. Art.
Resistance on the inhale-exhale - 50 mm waters Art.
Non-waste storage time - 12 hours
Kriolang AK-3 is made of stainless metal and is anti-magnetic.
Brass available and aluminum parts are covered with anti-corrosion coating resistant to the effects of sea water.
1 - carrying handle; 2 - breathing apparatus; 3 - Dewar vessels; 4 - valve; 5 - heat exchanger breathing mixture; 6 - ridges; 7 - gravitational
valve; 8 - heat exchanger-evaporator; 9 - safety valve; 10 - bleed nozzles; 11 - compensator; 12 - pipelines; 13 - charging nipple; 14 - cap nuts; 15 - filling button compensator; 16 - corrugated hoses; 17 - bellows; 18 - weighted limiters; 19 - heat reflecting screens; 20 - fence
branch pipes; 21 - spacer rings; 22 - adsorbent; 23 - outer vessel Dewar; 24 - internal Dewar vessel; 25 - heat exchanger; 26 - intake backup system; 27 - handle of a two-way crane; 28 - two-way howling crane; 29 - protective casing.
Cryolang device
Cryolang AK-3 (Figure 1) consists of two Dewar 3 vessels, internal 5 l each attached from two sides to the compensator buoyancy 11. Attached to the compensator breathing machine 2 with two corrugated hoses 16 and mouthpiece, valve 4, which serves to shut off the gas stream during non-waste storage, respiratory heat exchanger mixtures 5, heat exchanger - evaporator 8, gravity valve 7, safety valve 9, filling button water compensator 15 and belt system for fixing the device on the swimmer's body.
At the bottom of the device on a protective the casing 29 is attached charging fitting 13 for filling the device liquid breathing mix, two-way
crane 28, serving to raise pressure in the Dure vessels at the beginning of the work (start) and to enable reserve respiratory selection systems
mixture (reserve). Vessels Dewar made of stainless become.
Charge the device with liquid air or liquid air - oxygen mixture through a special charger hose. For this with a charger and two bleed nipples
remove plugs, charging hose connect to the charging nipple, and pressurized liquid breathing mix 1-2 kg / cm2 from transport Capacity is poured into the device. Through 3-5 minutes from bleed nipples 10 droplets of liquid appear what is the indication of termination charging The hose is disconnected plugs put in place.
Inner tank wall thickness 24 is 0.8 mm, outer - 1.2 mm. Outer tank has convex annular ridges 6 in which on the inside nested spacers rings 21 to increase resistance to external hydrostatic pressure. At the top vessels installed handle 1 that serves for carrying the apparatus, and in
bottom are fittings for refueling and collection of liquid respiratory mixes. In the inner tank each vessel in opposite The ends are mounted on bellows 17 two intakes 20 each with limiters 18. The latter serve for order not to choose completely breathing mix. And so intakes in horizontal position all the time were in the "liquid phase" respiratory mixture, limiters made weighted. Themselves intakes have such a design so that in fully filled vessels there was a gas cushion.
One of the vessels is connected to the start-up liquid extraction system respiratory mix and has inside a heat exchanger 25 serving to increase
pressure in the vessel during preparation apparatus to work, and the intake 26 for the selection of reserve liquid respiratory mix.
Vacuum screen insulation system. The space between the inner and the outer shells are filled screens 19 of aluminized film and pre-evacuated up to pressure 10-3 mm Hg Art. Further evacuation promotes cold and pre placed under the screen adsorbent 22 Breathing machine (fig. 2) provides air supply swimmer under pressure equal to the depth dive, and fixed on compensator housing. It consists of two housings connected between by myself. Between the case is clamped rubber membrane 2. In one case air supply installed valve 3, check valve 1 for equalizing the pressure in the compensator, ejector 4 to reduce resistance on the inhale, levers 5. In the second mounted fungal
exhalation valve 6, exhalation valve seat, button 7.
The average cavity of the respiratory machine, formed by a membrane and exhalation valve through the holes in the case freely communicates with environment. Distinctive feature of this machine - low resistance to inhalation and exhalation on all modes of operation and on all the depths. This is achieved by the fact that supply lines and saddle valves have a cross section above 38 mm2 , and on exhalation applied equal fungal valve the membrane.
Gravity valve (Fig. 3) serves to switch the gas flow depending on the position swimmer so that in intake pipes only come in liquid breathing mix. By this stable pressure is provided in a gas cushion of vessels and uniform liquid respiratory flow rate mixtures, as well as the constancy of gas mixes on all operating modes of the device.
Gravity valve is hollow metal tube 3 with three chokes. On both sides of the tube ends with saddles 1. Inside tube has a cylindrical shape
load 4, moving freely under its own weight.
From the front side the load ends valves 2 disc type. When the gravity valve is upright respiratory mixture can pass only through the top saddle which connected by pipelines with intakes, dipped in liquid phase respiratory mix. Lower saddle in this time is covered with disc
a valve that pushes the load and gas flow through the top saddle.
Charging hose (fig. 4) is a metal hose 0.5 m long, made of stainless steel helical bellows 4, braided top protective mesh 3. The ends of the charging hose come to an end with special cap nuts 1 and 6, one of which has a strainer 5. Handle 2 eliminates turning possibility frozen hose when it is disconnected after refueling.