Carrying out a working inspection does not take much time and does not require special effort. A properly performed operational equipment check will allow you to avoid many troubles.
1. Check the pressure in the cylinders.
To do this, it is necessary to attach a high pressure control gauge instead of the gearbox. Close the tap on the pressure gauge. Open the main and backup air supply valves. Read the readings on the pressure gauge. Then close the valve, open the tap on the high pressure gauge (bleed air from the pressure gauge), remove the pressure gauge.
2. External inspection.
A) Check the complete set and correct assembly of the scuba tank (fastening the gearbox, lung demand valve, clamps, belts, etc.), you can take the scuba tank by the straps and shake it lightly.
B) Adjust the straps
3. Leak test
A) Dry.
With the valves closed, try to inhale from the lung demand valve. At the same time, the tightness of the membrane, exhalation valves, and connections is checked. Everything is fine if you can’t take a breath.
B) Wet.
Open all valves. Place the lung demand valve under the cylinder and lower the cylinder into the water. If there are air bubbles from under the connections, the scuba tank is faulty.
4. Checking the operation of the bypass valve (reserve).
Open the main air supply valve using the button forced submission air demand valve, bleed some air (about 20-30 sec.). Next, open the reserve air supply valve. In this case, you should hear the characteristic noise of air flowing from cylinder to cylinder.
This test does not determine the amount of bypass valve actuation. After completing all the steps, you make sure that you have a working bypass valve in your scuba tank and, as a result, there is a reserve.
AVM-5 scuba adjustments
1. Adjusting the set pressure of the reducer
2. Adjustment of the gearbox safety valve response
3. Adjustment of the lung demand valve
4. Adjusting the operation of the bypass valve (reserve)
Adjusting the set pressure of the reducer (8-10 ati)
1. Measurement of the set pressure value.
Disconnect the lung demand valve.
Attach a control pressure gauge (0-16 ati) to the hose.
Close the tap on the control pressure gauge.
Open the main air supply valve.
Measure the pressure (8-10 ati).
Close the main air supply valve.
Open the tap on the control pressure gauge (bleed air)
2. Adjustment.
Unscrew the gearbox cover (1) Fig. 4
Pull out the piston (2) Fig. 4. To do this, screw a puller (or pick up a screw) into the threaded hole in the upper part of the piston and pull the puller. Then the piston can be easily pulled out. Using a screwdriver and trying to pry the piston by the edge is not recommended.
To increase the set pressure, it is necessary to compress the gearbox spring (3) Fig. 4
To reduce it, the spring must be weakened.
Two types of gearboxes were produced.
In the first case, to adjust the installation pressure, it is necessary to place or remove special adjusting washers under the spring (3).
In the second case, it is necessary to move the adjusting nut (7) along the thread of the bushing (8) Fig. 4.
In both cases, the meaning of all actions is to compress or decompress the spring (3)
Next, the gearbox is assembled and the set pressure is measured again.
Adjustment and measurement manipulations are carried out until the set pressure value is equal to 8-10 atm.
Adjusting the response of the safety valve (10-12 ati)
All operating instructions for AVM scuba gear recommend adjusting the operation of the safety valve at a repair and control unit (RCU).
The safety valve is screwed onto a special fitting on the RKU. Pressure is applied to the valve, and by the compression force of the spring (11) Fig. 5, the valve is adjusted to the desired pressure.
In practice, adjustment is performed in a slightly different way.
1. Adjust the reducer to the set pressure
2. Unscrew the locknut on the safety valve
3. Slowly rotating the valve body (12) Fig. 5 counterclockwise until the valve starts to operate.
4. Tighten the valve body (12) half a turn clockwise, and the valve will stop releasing air.
5. Tighten the locknut.
Thus, we will adjust the valve to an opening pressure that will be slightly higher than the set pressure (by 0.5-2 ati)
Adjusting the lung demand valve
The operating instructions for the scuba tank say that the lung demand valve cannot be adjusted.
In practice, adjusting the ease of breathing (inhalation resistance) can be done by bending the lever (5) Fig. 6. When bending the lever, the distance between the membrane (4) and the lever (5) Fig. 6 changes; the greater the distance, the greater the resistance when inhaling. It should be noted that if the lung demand valve is adjusted correctly, then when it is placed in water, air will randomly escape with the mouthpiece up. If the lung demand valve is turned with the mouthpiece down (as shown in Fig. 6), the air stops coming out.
Adjusting the operation of the bypass valve (reserve)
1. Measuring the pressure adjustment of the bypass valve.
When measuring this value, it is necessary to charge the device to a pressure of at least 80 ati.
Unscrew the gearbox and lung demand valve.
With the backup air supply valve closed, open the main air supply valve.
Vent the air.
When the air stops coming out, screw a high-pressure test pressure gauge (0-250 ati) to the fitting (instead of the gearbox).
Close the tap on the pressure gauge.
The pressure gauge should show 0 ati.
Next, open the backup air supply valve and wait until the pressure in the cylinders is equal (the characteristic noise of flowing air will be heard).
The pressure that the pressure gauge shows will correspond to the pressure of the reserve air supply.
Multiplying the resulting value by 2, we obtain the response pressure of the bypass valve.
The pressure of the reserve air supply should be within 20-30 ati, respectively, the response pressure of the bypass valve should be within 40-60 ati.
2. Adjustment
If the measurement results indicate the need for adjustment.
Bleed remaining air from the cylinders.
Loosen the clamps
Let loose union nuts adapter (you can use a gas wrench).
Move the cylinders apart and remove the adapter (3)
At the point where the adapter (3) is attached to the cylinder with valves, access to the bypass valve adjusting nut will open.
Compressing or releasing the bypass valve spring, using the adjusting nut, change the setting. If it is necessary to increase the adjustment pressure, then compress the spring (turn the nut clockwise), if to decrease it, release the spring.
3. Assemble the cylinder.
4. Charge up to 80 ati.
5. Take a measurement.
6. Repeat the adjustment if necessary.
O-rings and machine lubrication
To ensure tight connections, the device uses rubber O-rings of various diameters.
To prevent drying out, the rings must be lubricated. Technical petroleum jelly (CIATIM 221) or its substitutes are used for lubrication.
The ring to be lubricated must be placed in the grease, left for some time (5-10 minutes), then cleaned of excess grease and installed in place.
In addition, the device lubricates the rubbing parts of the gearbox (piston). Lubricant is applied and then excess is removed.
Frequency of device checks.
Operational check - before each descent
Small check (checking all adjustments, lubrication of O-rings) - before the start of the season
Full check (small check + complete disassembly and reassembly) - upon receipt from the warehouse, in case of doubt about serviceability, after long-term storage
The AVM-3 breathing apparatus (Fig. 36) consists of the following main parts:
- a breathing machine that serves for pulsating air supply at the moment of inhalation and stopping the supply at the moment of exhalation;
- reducer designed to reduce pressure compressed air in the apparatus cylinders (150 kgf/cm 2) up to the setting 3-4 kgf/cm 2;
- two air cylinders with a capacity of 5 liters each, for a working pressure of 150 kgf/cm 2, which contain a supply of compressed air;
- a valve used to shut off the outlet of compressed air from the cylinders;
- reserve supply valve used to supply reserve air from the apparatus cylinders;
- a valve box designed to connect the breathing system of the apparatus to a diving suit helmet or a wetsuit;
- a high-pressure pressure gauge used to control the pressure in the cylinders of the anhp arata;
- inhalation and exhalation tubes used to connect the valve box to the breathing machine.
Rice. 36. Schematic diagram device AVM-3:
1 - breathing machine; 2 - gearbox; 3 - cylinders; 4 - valve; 5 - backup valve; 6 - valve box: 7 - pressure gauge; 8 - inhalation tube; 9 - exhalation tube; 10 - valve valve; 11 - nozzle; 12 - metal membrane; 1З - spring; 14 - gear valve; 15 - breathing machine valve; 16 - membrane; 17, 18 - levers; 19 - seat of the breathing machine; 20 - exhalation valve; 21 - petal; 22 - safety valve; 23 - valve (return); 24 - spindle; 25 - hard center; 26 - inlet fitting; 27 - hose VSh-1; 28 - valve (return); 29, 30 - filtersOperating principle of the AVM-3 device during autonomous breathing. Air from the apparatus cylinders is supplied as follows; Before the diver starts diving, open valve 4 on the cylinders and close valve 5 of the reserve supply. Through the open valve of valve 4 and the nozzle in valve 5, air pressure spreads under the membrane into cavity B, bends the membrane, overcoming the force of the valve spring 13, and opens the seat through which air passes under the gearbox valve.
In the gearbox high pressure air is reduced to a working level of 3-4 kgf/cm 2 and the air passes under the valve of the lung demand valve.
During inhalation in the tube and submembrane cavity A of the breathing machine, the pressure decreases, the membrane bends inside the body, presses on lever 17, which, in turn, presses on lever 18, and the latter presses on the valve rod on A5. The valve moves away from the seat 19 and the air passes into cavity A of the breathing machine and then through the tube for inhalation. When exhaling in the tube and submembrane cavity A is created overpressure Compared to the ambient pressure, the membrane bends in the other direction, releases the levers 17 to 18 to the valve 15 under the air pressure coming from the gearbox 2, is pressed against the seat, the flow of air into the cavity of the pulmonary valve stops.
Simultaneously with exhalation, valve 20 opens and air exits through the rubber petal valve and the holes in the lung demand valve cover to the outside.
The operating diagram of the breathing machine ABM-3 during inhalation and exhalation is similar to the operating diagram of the pulmonary valve of the A.BM-1M device.
If the air pressure in the reducer chamber increases by more than 5-8 kgf/cm2, safety valve 22 vents it out.
Check valve 23 is pressed against the seat by air pressure and closes the air outlet from the apparatus through the outlet fitting of the hose.
When the pressure in the cylinders drops to 45-30 kgf/cm2, spring 13, overcoming the force of air pressure under the membrane, presses the membrane to the seat through the spindle and the rigid center and closes the seat hole. After this, air passes to the gearbox only through the nozzle.
The flow area of the nozzle does not provide a complete inhalation, as a result of which the exhalation resistance increases and the diver’s breathing becomes difficult. In this case, the diver must rise to the surface.
To restore normal breathing, he manually opens valve 5 by turning its handwheel a quarter turn. When the handwheel is turned, the spindle rises, compresses spring 13, releasing the hard center and the membrane, which bends under air pressure and opens the seat. The amount of air per breath increases.
Operation of the AVM-3 apparatus when air is supplied through a hose from the surface. Before diving, valves 4 and 5 are closed. The VSh-1 diving hose is connected to the inlet fitting 26 of the lung demand valve (shown as a dotted line in Fig. 36). Compressed air is supplied from the surface to the hose, the pressure in which is maintained at 1-4 kgf/cm 2 excess above the depth pressure.
The air passes through the hose through valve 23 to valve 15 and is inhaled in the same way as described above. If the air supply stops, the diver manually opens valve 4 on the cylinder through the hose, while breathing air from the cylinders of the device.
When supplying air through a hose check valve 28 is pressed by air pressure to the seat and closes 1 air passage into the cavity of the gearbox 2.
Are common technical specifications according to GOST R 51364-99
The devices are designed for condensation and cooling of vaporous, gaseous and liquid media used in technological processes oil refining, petrochemical and other related industries.
AVM devices are manufactured in two versions - horizontal and vertical. The device consists of one pipe section assembled from bimetallic finned pipes, located horizontally for the AVM-G horizontal type device and vertically for vertical type AVM-V. The sections are blown by an air flow, which is pumped by an axial fan.
The devices are equipped with explosion-proof electric motors.
It is possible to equip the devices with louver devices with manual or automatic rotation of the dampers, as well as a humidifier and air heater. Devices can be manufactured with load-bearing structure, intended for installation of devices in areas with seismicity up to 9 points and with high-speed wind flow in the V geographical region. The devices can be manufactured with chambers for a heated air recirculation system.
Connection and dimensions in accordance with TU26-02-1121-96.
TECHNICAL SPECIFICATIONS
Heat transfer surface area:
- with a length of heat exchange pipes of 1.5 m - 105 * 375 m2
- with a length of heat exchange pipes Zm - 220*775 m2
Conditional pressure - 0.6; 1.6; 2.5; 4.0; 6.3
Electric motor type - AHM100S4
Electric motor power - 3 kW
Fan wheel speed - 1500 rpm
Number of fan wheels in the device
- with a length of heat exchange pipes of 1.5 m - 1 piece
- with a length of heat exchange pipes Zm - 2 pcs.
Pipe finning coefficient (conditional) - 9; 14.6; 20
The number of rows of pipes in a section is 4; 6; 8
Number of pipe strokes in a section
- when the number of rows of pipes in section 4 is 1:2; 4
- with the number of rows of pipes in section 6 - 1;2;3;6
- with the number of rows of pipes in section 8 - 1;2;4;8
Pipe length - 1.5; 3m
Material design of the section - B1;B2;B2.1;BZ;B4;B5
Device weight:
- with fin coefficient 9 - 1160-4210 kg
- with a finning coefficient of 14.6; 20 - 1130-4230 kg
Type of pipe sections - cap
Note: Material inner tube depending on material performance. B1 - steel 20; B2.1 - 15Х5М or Х8; BZ - 12Х18Н10Т, 08Х18Н10Т, 08Х22Н6Т; B4-steel 10Х17Н13М2Т; B5 - LAMSH77-2-0.05.
Example of a symbol:
AVM-V-9-0.6-B1-V/4-2-1.5 UHL1 Low-flow device of vertical type with fin coefficient of heat exchange pipes 9, nominal pressure 0.6 MPa, material design of section B1, explosion-proof electric motor, with the number of rows of pipes in the section 4, with the number of pipe strokes 2 with a pipe length of 1.5 m, climatic design in accordance with GOST 15150-69.
AVM-G-9-0.6-B1-V/4-2-1.5 UHL1 Low-flow device of horizontal type with fin coefficient of heat exchange pipes 9, nominal pressure 0.6 MPa, material design of section B1, explosion-proof electric motor, with the number of rows of pipes in the section 4, with the number of pipe strokes 2, with a pipe length of 1.5 m, climatic design in accordance with GOST 15150-69.
The holding's enterprises produce products for various industries, including shipbuilding and marine technology.
SHAP-R
The air-breathing apparatus ShAP-R is designed to ensure the breathing of a diver when performing work at depths of up to 60 m with pulmonary ventilation up to 60 l/min when working in a hose version, as well as in stand-alone version and for emergency ascents. It is capable of operating in conditions of heavy pollution, which allows for rescue operations, for example, during oil spills. Today it has already entered service with the Ministry of Emergency Situations.
All main components of the device are located in a small-sized impact-resistant plastic case;
- A special design, made in a streamlined shape, allows you to work in cramped conditions;
- Eliminates the possibility of snagging and entangling, prevents any mechanical damage;
- The device has additional medium-pressure ports for connecting a second lung demand valve, an inflating hose for a diving suit or a buoyancy compensator vest, as well as pneumatic tools;
- A special feature is also the design of the unit connecting the device to the diving hose, which allows you to manually (without using a tool) uncouple the diving hose in any conditions, including: under water, under pressure, as well as when leaving the water under pressure. low temperatures Oh.
- The ShAP-R device can be used (as a backup) in equipment with diving helmets such as Super Lite, X-Lite, etc.;
- A gearbox with a dry pickling chamber, as well as a pulmonary valve used in the device, allows you to work at extremely low temperatures of water and air, as well as in heavily polluted water.
AVM-15
The AVM-15 air-breathing apparatus is designed to provide breathing for a diver when performing underwater technical, rescue and other types of diving work in an autonomous and hose version, including in conditions of low water and air temperatures, as well as in polluted environments, including those with a high content of petroleum products.
The device works according to open system breathing (inhale from the apparatus, exhale into the water).
The AVM configuration includes 3 types of gearboxes (piston, diaphragm with a dry chamber, piston with a “dry etching chamber”) and 2 types of lung valves LAM-17 (with a mouthpiece) and LAM-17R (with a threaded fitting for working in wetsuits of the type UGK- 3).
The device ensures the diver’s breathing when performing diving work at depths of up to 60 m with pulmonary ventilation of up to 60 l/min;
- The device can be converted to work in a hose version;
- In addition to compressed air, it can be used with oxygen-enriched breathing gas mixtures, which significantly increases the efficiency of diving work;
- The device, when connected to a second pulmonary demand valve, ensures the breathing of two divers simultaneously;
- Meets the requirements of GOST R 52639 and EN 250;
- Unlike previous devices (AVM-5, AVM-7), in AVM-15 the high and medium pressure ports are adapted to the European standard;
- All components included in the AVM-15 device are completely interchangeable with imported analogues;
- The device includes a patented signaling device“bubble” type, signaling the depletion of the main air supply;
- Used on raid boats for integrated rescue support of project 23040.
AVM-21 "WALRUS"
The air-breathing apparatus is designed to ensure the breathing of a diver when he performs underwater technical, rescue and other types of diving work in autonomous and hose versions, in conditions of low water and air temperatures, as well as in polluted environments, including those with high concentrations of petroleum products.
The new technology used in the device solves the problem of freezing of the pulmonary apparatus in extreme conditions cold, due to which the scuba gear can operate reliably at temperatures down to -4 degrees for at least two hours. A reducer designed to reduce air pressure and supply it to the lung demand valve, thanks to new technology, simpler and more reliable than analogues and previous developments. In addition, springless technology has reduced total weight equipment.
The device operates using an open breathing system (inhale from the device, exhale into the water);
- The units of the device are located in a shock-resistant plastic case;
- Cylinder capacity 2*7 l;
- Operating pressure 300 kgf/cm2;
- Operating time at 30 l/min is 120 minutes;
- Thanks to the latest LAM-21 lung valve, the device is operational at water temperatures down to -4°C.
