The robust layer of the minelayer is a geometrically regular cigar-shaped body. The frames are made of box steel and are installed with a pitch of 400 mm (shpation), skin thickness from 12 to 14 millimeters. By the ends of the robust hull, ballast tanks, also made of box-shaped steel, were riveted; sheathing thickness was 11 millimeters. Between the 41 and 68 frames, by means of angular and strip steel, a keel with a weight of 16 tons, made of lead plates, was fastened with bolts to bolts. In the area of the 14 - 115 frames, the "displacers" - boules were located on the sides of the landlord.
Displacers consisting of 6 millimeters thick and angular steel plating were attached to the sturdy housing with knits 4 millimeters thick. Each displacer was divided into 5 compartments by four watertight bulkheads. The entire length of the underwater mine layer was lightweight superstructure with frames made of angular steel with a lining thickness of 3,05 millimeters (the deck superstructure had a thickness of 2 millimeters).
During the dive, the superstructure was filled with water, for which, from both sides in the aft, middle and fore parts, so-called “doors” (valves) were made, which opened from inside the robust bargaster's body.
In the middle part of the superstructure there was an oval in the cross section, made of 12-mm low-magnetic steel. Behind the cabin there was a breakwater.
For immersion served 3 ballast tanks: bow, medium and stern.
The middle tank was located between the frames of the robust hull 62 and 70 and divided the submarine into two halves: the bow, which was residential and aft allocated for the engine room. To move between these rooms served as a casing pipe. Two tanks — a low pressure tank with a capacity of 26 m 3 and a high pressure tank with a capacity of 10 m X NUMX — were an average tank.
The low-pressure tank was located between two flat bulkheads on the 62 and 70 frames and the outer skin, occupying the entire cross section of the submarine along the middle. The flat bulkheads were reinforced by eight links: one flat of sheet steel (full width of the submarine), which was at the height of the deck, and 7-th cylindrical, one of which is a passage for living space, 4 - high-pressure tanks.
In the low-pressure tank, which was designed for pressure 5 atmospheres, two Kingston were performed, their drives were brought to the engine room. The tank was blown with compressed air through a bypass valve mounted on a flat bulkhead. The filling of the low pressure tank was carried out by gravity, pump or both. As a rule, the tank was flushed with compressed air, but the water could be pumped out with a pump.
The high-pressure tank consisted of four cylindrical vessels of different diameters, which were located symmetrically with respect to the diametral plane and passed through the flat bulkheads of the middle tank. A pair of high pressure cylinders was placed above the deck, a pair - under it. A high-pressure tank was a tear-off keel, that is, it performed the same role as a medium or tear-off tank in Bars-type submarines. It was blown with compressed air under pressure 10 atmospheres. The cylindrical vessels of the tank were connected by branch pipes, and each pair of vessels was equipped with its own Kingston.
The device of the air pipeline made it possible to let in air separately in each group, thanks to which this tank was used to level a significant roll. High-pressure tanks were filled by gravity, pump or both ways at the same time.
The bow ballast tank (volume 10,86 м3) from the robust hull was separated by a spherical partition on the 15 frame. The tank could withstand the pressure of the 2 atmosphere. Its filling was made through a separate Kingston, which was located between the 13, 14 frames and the pump. From the tank water was removed with compressed air or pump. But when water is removed by compressed air, the pressure difference inside the tank and outside should not exceed 2 atmospheres.
The aft ballast tank (volume 15,74 м3) was placed between the aft trim tank and the solid hull, and a spherical bulkhead on the 113 frame separated it from the robust hull, and a spherical bulkhead on the 120 frame separated it from the aft trim tank. This tank, like the bow, was designed for 2 atmosphere. It was also filled with pump or gravity through her own Kingston. Water was removed from the tank with compressed air or a pump.
On the barrier, in addition to the main ballast tanks listed above, there were auxiliary ballast tanks: feed and bow equalizing and differential tanks.
The bow trim tank (a cylinder having spherical bottoms) with a volume of 1,8 m3 was located in the superstructure of the submarine between the frames 12 and 17.
According to the original design, it was located inside the ballast tank nasal; however, due to the lack of space in the latter (it contained torpedo-cutters, the drive and shafts of the horizontal bow steering, pipes from the gates of the anchors and the well of the underwater anchor), it was transferred to the superstructure.
The bow trim tank was calculated for 5 atmospheres. It was filled with water by a pump, and removal by compressed air or a pump. The location of the bow trim tank in the superstructure above the submarine cargo waterline must be recognized as unsuccessful, which was confirmed during the operation of the minelayer.
The bow trim tank in the fall of 1916, was removed from the submarine, and its role was performed by the bow cisterns of the displacers.
The aft trimming tank (volume 10,68 м3) was located between the frames 120 and 132, it was separated from the aft ballast tank using a spherical bulkhead.
This tank, as well as the bow, was calculated on the pressure 5 atmospheres. The feed trim tank, unlike the bow tank, can be filled both by gravity and with a pump. Removal of water from it was carried out with compressed air or pump.
There were four equalizing tanks with a total volume of 1,2 m 3 on the minelayer to offset the residual buoyancy. Two tanks each were located in front of and behind the cabin. Filling occurred by gravity through the crane, located between the frames of the cabin. Water was removed with compressed air.
In the nose compartment, between the 26 and 27 frames, two small centrifugal pumps were installed, in the middle pump compartment between the 54-62 frames - two large centrifugal pumps, and on the deck between the 1-2 and 105 frames - XNUMX-XNXX -XNXX-XNUMX-XNUMX-XNUMX-XNUMX-XNUMX and XNUMX.
Each small centrifugal pump (35 m3 performance per hour) was driven by 1,3-strong electric motors. The starboard pomp was serviced by replacement tanks, cisterns of provisions and drinking water, torpedo replacement and oil tanks of the starboard. A left-hand pomp was serviced by a nasal trim tank and a left-side oil tank. Each of the pumps was equipped with its own onboard Kingston.
Each large centrifugal pump (performance of one 300 m3 pump per hour) was driven by 17-strong electric motors. The starboard pump worked on the high-pressure tank and the bow ballast tank. Pomp of the left side was serviced by a low pressure tank. Each of the pumps was equipped with its own kingston.
One large centrifugal pump, having the same capacity and installed in the stern, was used to service the fodder ballast and trim tanks. This pump was also supplied with its own kingston.
The ventilation pipes of high and low pressure tanks were put into the roof of the forward part of the wheelhouse fence, and the aft and bow ballast tanks ventilation pipes - onto the superstructure deck. The ventilation of the stern and fore trim tanks was brought inside the submarine.
According to the project, the compressed air supply at the mine layer was 125 м3 with a pressure of 200 atmospheres. The air was in 36 steel cylinders: in the stern, in kerosene (fuel) tanks were placed 28 cylinders, under the torpedo tubes in the nose compartment - 8.
Nasal cylinders were divided into two groups, feed - into four. Each group had an independent connection to the air line. To reduce the pressure to 10 atmospheres (for a high-pressure tank), an expander was installed in the bow of the submarine. A further decrease in pressure was carried out by incomplete opening of the intake valve, as well as adjustment by the pressure gauge. Compression of air to 200 atmospheres was carried out using two electro-compressors with a capacity of 200 m3 per hour each. Compressors were installed between the 26 and 30 frames, and the compressed air line was laid on the left side.
To control the underwater mine layer in the horizontal plane served as a vertical balance wheel (area 4,1 м2). The wheel could be controlled in two ways: manually and by means of an electric control. In the latter case, the rotation of the steering wheel is transmitted through a chain of Gall and gear wheels on the side steering wheel, which consisted of steel rollers.
From the sturtros the movement was received by the steering machine connected to the 4,1-strong electric gear motor. The engine set in motion the subsequent transmission to the tiller.
There were three control posts for the vertical rudder on the barrier: in the wheelhouse, on the bridge of the wheelhouse (removable steering wheel, which was connected to the wheel in the wheelhouse), and also in the aft compartment. The steering wheel on the bridge was used to control when sailing a submarine in a cruising position. For manual control, a post was used in the aft part of the underwater mine layer. The main compass was placed in the wheelhouse near the steering wheel, the spare compasses were located on the bridge of the wheelhouse (was removable) and in the aft compartment.
For vertical control of the mine layer when diving, two pairs of horizontal rudders were installed for diving / ascent. Nasal horizontal rudders (total area 7 m2) was located between the frames 12 and 13. The axis of the rudders were laid through the nasal ballast tank and connected with the hub of the screw-toothed sector, and the latter was connected to the worm screw, from which a horizontal shaft passed through a spherical bulkhead. The steering machine was placed between the torpedo tubes. The rudder angles ranged from minus to plus 18 degrees. The control of these rudders, as well as the vertical rudder, is manual and electric. When electrically controlled, the horizontal shaft was connected with a 2,5-strong electric motor using two pairs of bevel gears. With manual control included an additional gear. There were two rudder position indicators: one mechanical, located in front of the helmsman, and an electric one, at the commander of the submarine.
Around the helmsman located depth gauge, trimmer and inclinometer. The handlebars were protected by tubular guards from accidental strikes.
In their design, the aft horizontal rudders were similar to the nose rudders, but their area was slightly smaller - 3,6 m 2. The steering machine of the horizontal stern rudders was located in the aft compartment of the submarine between the 110 and 111 frames.
The haul was supplied with one underwater anchor and two deadlocks. The mass of the Hall anchors was 25 pounds (400 kilogram) each, with one of them being spare. The anchor line was located between the 6 and 9 frames and was pass-through on both sides. The clump of the steel sheet pipe was connected to the upper deck of the superstructure. This device allows you to anchor from each side at will. An anchor spire, rotating 6-strong electric motor, could also serve as a mooring submarine. The underwater anchor, which had the same mass and was a steel casting with mushroom expansion, was placed in a special well on the 10 frame. To raise the underwater anchor used the left side electric motor, which served the base anchor.
Six fans were installed to ventilate the underwater mine layer. Four fans (each powered by an 4-strong electric motor) with an 4000 m3 performance per hour were in the middle of the sub-boat's pump and aft compartments (in each room, the 2 fan).
In the middle pump room, there were two 54 m480 fans per hour near the 3 frame (they were driven by horsepower 0,7 electric motors). They vented the batteries; their performance was ensured during the hour 30-fold air exchange.
On the barrier, there were two ventilating descending pipes, which were automatically closed when they were lowered. The nose ventilation pipe was located between the 71 and 72 frames, and the aft ventilation pipe was located between the 101 and 102 frames. At the time of immersion, the pipes were laid in special enclosures in the superstructure. The pipes in the upper part initially ended with sockets, but then they were replaced with caps. The pipes were raised / lowered by worm winches, the drive of which was located inside the submarine.
From the nose fans, the pipes passed through the middle ballast tank and were combined in a fan box, from which a common pipe led to the descending part.
The pipes of the feed fans went on both sides to the 101 frame, where they were connected into one pipe, which was laid to the turning part of the fan pipe in the superstructure. The tube of the battery fans was attached to the branch pipe of the main nose fans.
The minelayer was controlled from the cabin where the commander was located. The wheelhouse was located amidships of the submarine and in the section was an ellipse with the 1,75 and 3 axes of the meter.
The casing, the bottom and the four frames of the cabin were made of low-magnetic steel, with the thickness of the upper spherical bottom and plating - 12 millimeters, and the bottom flat bottom - 11 millimeters. An 680-millimeter round mine, located in the middle of the submarine, led into a robust hull of a wheelhouse. The upper exit hatch, which was somewhat shifted to the nose of the submarine, was closed by a cast bronze lid, equipped with three zadraykami and a valve through which the spoiled air was released from the cabin.
Thumbs of two periscopes were attached to the spherical bottom. The periscopes of the Hertz system had a 4 meter dyne and were located in the aft part of the cabin, with one of them shifted to 250 mm to the left, and the second in the center plane. The first periscope is of a binocular type, the second is a combined panoramic one. In the felling basement, a 5,7-strong electric motor was installed to lift the periscopes. For the same purpose used manual drive.
In the wheelhouse are placed: the main compass, the position indicators of the horizontal and vertical rudders, depth gauge, the steering wheel of the vertical rudder, engine telegraph, cranes control leveling tanks and high-pressure tanks. Of the nine windows with covers, three were located in the exit hatch and six in the cabin walls.
Two bronze three-bladed screws with rotary blades with a diameter of 1350 millimeters were installed on the barrier. To the mechanism for transferring the blades, which was placed directly behind the main electric motor, a conversion rod passed through the propeller shaft. The change of stroke from full front to rear and vice versa was performed manually and mechanically from the rotation of the propeller shaft. For this there was a special device. The 140 mm propeller shafts were made of Siemens-Martin steel. Used ball thrust bearings.
For the surface course, four kerosene eight-cylinder two-stroke Curting engines were used. At 550 revolutions per minute, the power of each was 300 HP. Motors were placed on two on board. Between themselves and with the main electric motors were connected by friction clutches. All eight engine cylinders were designed in such a way that when the crankshaft halves were separated, each four cylinders could work separately. Thus, a combination of horsepower on one board was obtained: 150, 300, 450 and 600 horsepower. The exhaust gases from the engines were fed to a common box on the 32 frame, from which was a pipe that serves to bring them to the atmosphere. The upper part of the pipe, which went out through the breakwater in its aft part, was lowered. The mechanism for lifting this part of the pipe was in the superstructure and manually driven.
Seven individual kerosene cylinders (total capacity of 38,5 tons of kerosene) were housed inside a sturdy casing between the 1-2 and 70 frames. Spent kerosene was replaced with water. The kerosene required for the operation of the engines was fed into two consumable tanks from tanks with a special centrifugal pump. Kerosene was supplied by gravity from consumable tanks to motors.
For the underwater course was provided two main electric motors of the Eklerazh-Elektrik system. At 400 rpm, the power of each was 330 hp The electromotors were located between the 94 and 102 frames. They allowed a wide adjustment of the speed from 90 to 400 due to the different grouping of semi-batteries and anchors. The motors directly worked on the propeller shafts, while during the operation of the kerosene engines of the armature electric motors served as flywheels. Electric motors with kerosene engines were connected by friction clutches, and pin clutches - with persistent shafts. Separation and engagement of clutches was carried out with special rattles on the shaft.
The underwater mine-layer rechargeable battery, located between the 34 and 59 frames, consisted of the Meto 236 rechargeable batteries. The battery was divided into two batteries, each of which included half-batteries for 59 elements. They could be connected in parallel or in series. The batteries were charged by the main electric motors, which worked as generators and were driven by kerosene engines. Each of the main electric motors had its own main station, which was supplied for connecting semi-batteries and anchors in parallel and in series, shunt and starting rheostats, measuring instruments, a relay for braking, and the like.
Two torpedo tubes were installed on the barrier, placed in the bow of the submarine, parallel to the center plane. Devices built by the St. Petersburg plant "GA Lessner", intended for shooting 450-mm torpedoes of the 1908 model of the year. There were ammunition of four torpedoes on the barrier, two of which were in the torpedo tubes, and two were stored under the living deck in special boxes.
To transfer the torpedoes to the apparatus from the boxes on both sides, there were rails along which the trolley with hoists moved. A substitution tank was placed under the deck of the nasal compartment, where the water descended by gravity from the torpedo tube after the shot. For pumping water from the tank served as the nasal pump starboard. To flood the volume between the torpedo tube and the torpedo water, tanks of an annular gap in the nose section of the propellants from each side were intended. Torpedoes were loaded through an inclined nose hatch with the help of a minbalk, which was installed on the deck of the superstructure.
On a special type of 60 mines, they were placed symmetrically with the center plane of the submarine in two channels of the superstructure. The superstructure was equipped with mine paths, aft embrasures through which the mines were loaded and set, as well as a swivel folding crane for loading the mines. Mine paths - rails, riveted to a sturdy body, along which vertical rollers of anchors of mines rolled. To prevent mines from derailing, along the sides of the minelayer, beds with squares were made, between which the side rollers of the anchor mines moved.
By mines, mines moved with the help of a worm shaft, into which the leading rollers of mine anchors, moving between the specials, went. directing epaulets. An electric motor of variable power was used to rotate the worm shaft: at 1500 rpm, 6 hp; at 1200 rpm - 8 hp An electric motor installed from the starboard in the nose of the barrier between the 31 and 32 frames was connected to the vertical shaft with a gear wheel and a worm. The vertical shaft, passing through the gland of the strong hull of the submarine, was connected with the worm shaft of the starboard side of the bevel gear. The right vertical shaft for transmitting the movement of the left side worm shaft was connected to the vertical left shaft using a transverse gear shaft and bevel gears.
Each of the rows of the mine side began a little ahead of the nasal entrance hatch of the underwater mine layer and ended at a distance of about two minutes from the embrasure. The loophole cover was a metal shield with rails for mines. Mines were supplied with an anchor - a hollow cylinder with vertical rivets riveted at the bottom of the 4 brackets, rolling along mine tracks. In the lower part of the anchor two horizontal rollers were installed, which were included in the worm shaft. When the shaft rotated, the rollers slid in its cutting and moved the mine. After the mine with an anchor fell into the water occupying the vertical position of the spec. the device disconnected the mine from the anchor. At the anchor, a valve was opened, after which water flowed into it, imparting negative buoyancy. At the first moment of time, the mine fell along with the anchor, and then surfaced to a predetermined depth, since it possessed positive buoyancy. A special device in the anchor allowed the minrep to unwind to a certain depth depending on the set depth of the setting. All the preparatory work for setting mines (installation of the firing glasses, depths, and so on) was performed in the port, since after the mines were taken into the mine layer superstructure, they were not accessible for these works. As a rule, mines were staggered at a distance of about 100 feet (30,5 meters). The speed of a minelayer when setting mines could be 3-10 nodes. Accordingly, the speed of setting min. The launch of the mine elevator, speed adjustment, closing and opening of the stern embrasures were made from inside the strong hull of the submarine. Indicators of the number of delivered and remaining mines and the position of the mines on the elevator were installed on the fence.
According to the original project, no artillery armament was provided for on the Krab underwater minelayer, but then, for the first combat campaign, one gun of the 37 mm caliber and two machine guns were installed on the fence. However, later 37-millimeter gun was replaced by a larger caliber gun. So on the "Crab" by March 1916, the artillery armament consisted of one Austrian mountain gun of the caliber 70 mm, installed before chopping, and two machine guns, one of which was installed behind the breakwater and the other in the nose.
The main elements and dimensions of the underwater mine layer "Crab":
Years built - 1906 / 1907 (1 option) / 1907 (2 option) / 1908 / 1909 (corrected) / 1912 / 1915 (reporting);
Surface displacement - 300 t / 450 t / 470 t / 500 t / 500 t / 512 t / 533 t;
Underwater displacement - ... / ... / ... / ... / ... / 722,1 t / 736,7 t;
Length - 27,4 m / 45,7 m / 45,7 m / 51,2 m / 52,8 m / 52,8 m / 52,8 m;
Width - 4,6 m / 4,6 m / 4,6 m / 4,6 m / 4,3 m / 4,3 m / 4,3 m;
Draft - 3,66 m / ... / ... / 4,02 m / 3,9 m / 3,54 m / 4,0 m;
Metacentric height on the surface with a full stock of mines - 305 mm / 380 mm / 305 mm / 255 mm / 255 mm / 255 mm / 310 mm;
Immersion depth - 30,5 m / 30,5 m / 30,5 m / 45,7 m / 45,7 m / 45,7 m / 36,6 m;
Immersion time - 10 min. / 10,5 min. / 5,5 min. / 4 min. / 4 min. / 4 min. / 12 min .;
Surface Speed - 9 knots / 10 knots / 15 knots / 15 knots / 15 knots / 15 knots / 11,78 knots .;
Submerged Speed - 7 knots / 6 knots / 7 knots / 7,5 knots / 7,5 knots / 7,5 knots / 7,07 knots .;
Surface range - 3 thousand miles / 3,5 thousand miles / 1 thousand miles / 1,5 thousand miles / 1,5 thousand miles / 1 thousand miles / 1236 miles;
Submerged range - 38,5 miles / ... / 21,0 miles / 22,5 miles / 22,5 miles / 22,5 miles / 19,6 miles;
The number and power of the main engines - 2 x 150 hp / ... / 2 x 600 hp / 4 x 300 hp / 4 x 400 hp / 4 x 300 hp / 4 x 300 hp;
The number and power of electric motors - 2 x 75 hp / ... / 2 x 125 hp / 2 x 150 hp / 2 x 200 hp / 2 x 300 hp / 2 x 330 hp;
Fuel stock - 40 t / ... / ... / 50 t / 50 t / 38,5 t / 37,14 t;
Battery capacity - ... / ... / ... / 4000 A.chas. / 4000 A.chas. / 4000 A.chas. / 3600 A.chas .;
The number of mines - 35 (28) / 60 / 60 / 60 / 60 / 60 / 60;
The number of torpedo tubes - 0 (2) / 1 / 1 / 2 / 2 / 2 / 2;
The number of torpedoes is 0 (2) / 3 / 3 / 4 / 4 / 4 / 4.
Part of 1. New project of underwater mine layer
Part of 2. The second and third variants of the underwater layer
Part of 3. Fourth, the latest version of the minelayer Naletova MP.
Part of 4. How was arranged underwater mine layer "Crab"
Part of 5. The first military campaign of the underwater mine layer "Crab"
Part of 6. "Crab" becomes in repair
Part of 7. The end of the first underwater mine layer "Crab"