The ship's hull is usually made "barrel-shaped", with special ice reinforcement in the waterline area ("ice belt"), "icebreaking" shape of the bow and "M-shaped" shape of the aft end, and the power plant is diesel or nuclear steam turbine with electric transmission.
This design of the hull provides it with increased strength, the ability to withstand the effects of ice: resistance to abrasion in the waterline area, as well as possible compression in ice fields. The shape of the nose allows "on the move" to crawl out to the edge of the ice, breaking it with its weight. The “M-shaped” shape of the stern is used to provide the ability to tow another vessel “on the mustache”, when the bow of the towed vessel is placed in the recess of the aft end (and at the same time the towed vessel can “push” the icebreaker). At the same time, the classic ("barrel-shaped") hull design, which works well in ice, gives the icebreaker not the best seaworthiness: on a wave in free water, it can rock quite strongly and sharply.
The diesel-electric (or nuclear turbo-electric) installation used on icebreakers in itself provides the ship with high maneuverability (on older icebreakers, steam engines with direct transmission were installed) and the ability to vary power. Modern domestic icebreakers, including nuclear ones, are built with three propellers. This is also aimed at improving the maneuverability and survivability of the ship's propulsion system. In addition, the power plant should provide the ship with increased autonomy, because when working in ice, refueling is practically impossible (icebreakers with steam engines could not pass the entire route of the Northern Sea Route without refueling).
4 Classification of icebreakers
Icebreakers can be classified according to the following criteria:
By appointment;
According to the navigation area;
By power plant capacity;
By type of power plant;
According to the method of overcoming ice obstacles;
According to individual design features.
By appointment
Most often, icebreakers are classified by purpose, on which power and its other main elements primarily depend. Thus, they distinguish:
Icebreakers-leaders who lead the escort of ships, leading the caravan and making a channel in the ice;
Linear icebreakers that perform the work of escorting, fencing and towing ships;
Auxiliary icebreakers used for tilting ships, their frags and towing.
By sailing area
In accordance with the classification of the Russian Register of Shipping, icebreakers have the following indicative performance characteristics:
LL6 - performance of icebreaking operations in and near port water areas, as well as in freezing non-Arctic seas with ice up to 1.5 m thick. Able to move continuously in a continuous ice field up to 1.0 m thick;
LL7 - performance of icebreaking operations: on the coastal routes of the Arctic seas in winter-spring navigation with ice thickness up to 2.0 m and in summer-autumn navigation with ice thickness up to 2.5 m; in non-Arctic freezing seas and in estuarine sections of rivers flowing into the Arctic seas - with an ice thickness of up to 2.0 m. Able to move continuously in a continuous ice field up to 1.5 m thick. The total power on the propeller shafts is at least 11 MW;
LL8 - performance of icebreaking operations: on the coastal routes of the Arctic seas in winter-spring navigation with ice thickness up to 3.0 m and in summer-autumn navigation - without restrictions. Able to move continuously in a continuous ice field up to 2.0 m thick. The total power on the propeller shafts is at least 22 MW;
LL9 - performance of icebreaking operations: in the Arctic seas in the winter-spring navigation with an ice thickness of up to 4.0 m and in the summer-autumn navigation - without restrictions. Able to move continuously in a continuous ice field up to 2.5 m thick. The total power on the propeller shafts is at least 48 MW.
By power plant capacity
The specialized literature presents the following conditional division of icebreakers according to the power of the SPP:
Powerful icebreakers with a main engine power of over 25,000 hp. c, which are usually used as leaders or liner icebreakers when escorting ships in the Arctic and freezing non-Arctic seas;
Medium icebreakers with engine power of 12,000 - 25,000 hp. With. They are commonly used as liner icebreakers for escort work in Arctic and freezing non-Arctic seas;
Small (auxiliary) icebreakers with engine power of 6000-12000 hp. With.
By type of power plant
On modern icebreakers, as a rule, ship power plants of two types are used:
Diesel-electric (most common);
Nuclear steam turbine with electric transmission.
By way of overcoming ice obstacles
According to the method of overcoming ice obstacles, icebreakers are divided into two groups: those that cut the ice with a sharp and reinforced stem, followed by the opening of the formed polynya, and those that push through the ice with the weight of the vessel with ice split.
According to individual design features
The icebreaker can have a different number of propellers (up to four). A four-rotor ship has two screws in the stern and two in the bow. This design increases the maneuverability of the icebreaker and reduces the likelihood of getting stuck in the ice.
To combat jamming on icebreakers, the following are used:
Roll and trim systems;
Pneumatic washer system (on modern ships).
The Yamal nuclear-powered icebreaker is one of ten Arktika-class icebreakers, whose construction began in 1986, back in Soviet times. The construction of the icebreaker "Yamal" was completed in 1992, but already at that time the need for its use to ensure navigation along the Northern Sea Route disappeared. Therefore, the owners of this vessel, weighing 23,455 tons and 150 meters long, converted it into a ship with 50 tourist cabins and capable of delivering tourists to the North Pole.
The "heart" of the icebreaker "Yamal" are two sealed water-cooled reactors OK-900A, which contain 245 fuel rods with enriched uranium. The full load of nuclear fuel is about 500 kilograms, this reserve is enough for the continuous operation of the icebreaker for 5 years. Each nuclear reactor weighs about 160 tons and is located in a sealed compartment, protected from the rest of the ship's structure by layers of steel, water and high-density concrete. Around the reactor compartment and throughout the ship, there are 86 sensors that measure radiation levels.
The reactors' steam power boilers generate high-pressure superheated steam that drives turbines that drive 12 electric generators. Energy from the generators is supplied to the electric motors that rotate the blades of the icebreaker's three propellers. The engine power of each propeller is 25 thousand horsepower or 55.3 MW. Using this power, the Yamal icebreaker can move through ice 2.3 meters thick at a speed of 3 knots. Despite the fact that the maximum thickness of ice through which an icebreaker can pass is 5 meters, cases of overcoming ice hummocks with a thickness of 9 meters have been recorded.
The hull of the Yamal icebreaker is a double hull coated with a special polymer material that reduces friction. The thickness of the upper layer of the hull in the place of ice cutting is 48 millimeters, and in other places - 30 millimeters. The water ballast system, located between the two layers of the icebreaker's hull, allows you to concentrate additional weight in the front of the vessel, which acts as an additional ram. If the power of the icebreaker is not enough to cut through the ice, then an air bubble system is connected, which ejects 24 cubic meters of air per second under the ice surface and breaks it from below.
The design of the reactor cooling system of the Yamal nuclear icebreaker is designed to use outboard water with a maximum temperature of 10 degrees Celsius. Therefore, this icebreaker and others like it will never be able to leave the northern seas and go to more southern latitudes.
Most ships have narrow decks, a V-shaped hull, an almost vertical bow, and are propelled by the rotation of a propeller that is connected directly to the ship's engine.
It's not like that with icebreakers. These ships are specially adapted for sailing on seas clogged with ice floes or heavy pack ice. Therefore, they are very heavy and lined with steel on the outside, which allows them to break ice 35 feet thick without any dents or holes. Their wide hulls and rounded bottoms also help to avoid such troubles.
Faced with pack ice, a powerful icebreaker lifts its curved nose and leans on the ice with all its weight. This is usually enough to make a pass. To perform such a maneuver, the propeller must push the ship forward with all its might and at the same time not be damaged. Therefore, the propeller of icebreakers is securely hidden under the ship's hull and is driven not by the ship, but by an electric motor. This allows the propeller to spin at an exceptionally low speed.
Japanese icebreaker "Shirazi" 440 feet long
The 440-foot-long Japanese icebreaker Shirazi is powered by three diesel engines, which are paired with electric motors that turn the propeller. The total output power of the icebreaker's engines is 90,000 horsepower.
Techniques for creating passages in ice seas
To open and navigate in the Arctic seas: to oil development, isolated scientific and military bases, to the strategically important northern ports, the help of icebreakers is required. Thin ice easily surrenders to these powerful ships, and they take it with a head-on ram. When it is necessary to break a floating ice floe or expand an open passage in the ice, the icebreaker, with the help of water overflowing in heeling tanks from one side to the other, leans to the side - as shown in the right figure. With such swaying, the ship's hull cuts and crushes the ice fields. Some icebreakers have additional lateral propellers mounted in the keel to facilitate rocking.
Performing icebreaking work using a roll
Having met pack ice, the icebreaker climbs it with its nose. In this case, the fuel from the bow ballast tank is poured into the stern tank (bottom left figure). When the entire bow of the ship is securely perched on the ice, the pumps begin pumping fuel back into the bow ballast tank. This added weight is usually enough to cause the ice to give way and move aside (right figure).
Performing icebreaking work with a ballast tank
Very wide ship
When the commander is on the suspension bridge, he can look down on his ship, which was created in order to awaken the polar seas to life. Typical icebreaker wider than a normal ship of the same length. This adds to its stability and carrying capacity.
Cup profile the bottom makes it easy to climb onto such ice fields that would simply wipe out an ordinary ship.
Steep bevel the bow is made so that the icebreaker, sliding, easily climbs onto the pack ice. And with the usual shape of the nose, the ship can only poke on such ice.
Marine icebreaker engine turns the generator. The generator powers the engine, which turns the propeller. This allows the best possible control of the ship's speed.
Icebreaker Yamal, one of the newest Russian Arctic vessels, breaks through hummocks
Hundreds of people swarm on the snow-covered surface of the frozen river. From a distance, what was going on there could be mistaken for a strange holiday or a wall-to-wall fist fight. However, approaching and looking closely, the observer would notice that in the movements of people there is an orderliness inherent in joint work. Several dozen men were chiseling a furrow in the ice with their picks, and then, joining hundreds of others, they harnessed themselves to an unusual mechanism - a long, twenty meters, pointed box, loaded in the back with cast-iron ingots. The projectile, nicknamed the ice sleigh, crawled onto the ice, pushed through it and crushed the broken blocks under itself, leaving behind a long polynya more than two meters wide crossing the river.
So in the times of Peter the Great, ice ferries were built, which were sometimes also equipped with cannons. Their nuclei crushed the ice along the ferry.
The Russian winter, which lasts nine months a year in the northern regions, spurred the inquisitive mind to look for unusual ways of sailing. And the fact that our country faces the Arctic Ocean, which is the shortest road from the European part of the country to the riches of Eastern Siberia and the Far East, forced us to go through the ice at the risk of life.
In pursuit of profit
Maritime business, brought under Peter I from Holland and England, brought many new words into the Russian language. However, Russia also enriched foreign languages with the maritime term: after all, both the German Eisbreher and the English icebreaker are tracing papers from the Russian word "icebreaker". And we owe this to the Kronstadt mayor Mikhail Britnev.
It is clear that the Russian breeder, who kept a small fleet on the St. Petersburg-Oranienbaum-Kronstadt line, was driven not by linguistic interest and not by pure ambition. The way to Kronstadt runs along the Gulf of Finland, covered with ice 120 days a year. In winter, they got there through the frozen sea on sledges, but as long as the ice was thin, the communication almost ceased.
An inquisitive businessman, familiar with the experience of the inhabitants of the Russian North - the Pomors, who have been sailing the Arctic seas on their wooden boats for more than five hundred years, decided to learn from their experience. The contours of the hull of the Pomeranian Kochi formed an acute angle of approximately 20-30 degrees in the bow. So Britnev also ordered the bow of his 60-horsepower steamship Pilot to be redone in the same way. And on April 25, 1864, much earlier than the usual start of navigation, the Pilot, breaking the melted ice, passed from Kronstadt to Oranienbaum, bringing a considerable additional income to its owner. Like the ancient "ice sleigh", the ship climbed onto the ice field and broke it with its weight. Later, the shipowner adapted his other steamship, the Boy, for ice navigation. Both ships served in St. Petersburg waters for about 25 years, having worked out the way to navigate ice fields, which is still used today by all icebreakers, including state-of-the-art nuclear ones.
In 1871, when unprecedented frosts fettered European northern ports, Hamburg industrialists turned to Britnev, and he sold them drawings of a converted Pilot for 300 rubles. According to these drawings, the first foreign icebreaker Eisbreher I was built, and the design of the ship was widely used in the world.
It was the success of the Britnev idea that gave the famous Russian naval commander and oceanologist Admiral Makarov the idea of building the first Ermak line icebreaker, which played a serious role in the development of the Arctic.
"Nut" among the ice
In his public lecture in 1897, "To the North Pole - ahead," Admiral Makarov stated: "No nation is interested in icebreakers, as much as Russia. Nature has frozen our seas with ice, but technology is now providing enormous means, and it must be admitted that at present the ice cover no longer presents an insurmountable obstacle to navigation.
A year later, the Yermak was launched in Newcastle, England. It was built according to the terms of reference developed under the guidance of Stepan Makarov himself and the famous Russian chemist Dmitri Mendeleev, who supported his risky project.
Indeed, as tests have shown, "an insurmountable obstacle" northern ice had no idea, and yet it was not easy to deal with them.
Archimedes, of course, was right when he asserted that a buoyant force equal to the weight of the liquid displaced by it acts on a body immersed in a liquid. However, in the ice, the ship is also subjected to monstrous lateral pressure, which can crush it like a shell. Therefore, the section of the icebreaker's hull is made in the form of a barrel or a nut, and the waterline should be below the widest part. Then the ice squeezing the icebreaker, no matter how hard they try, will push it out and will not be able to crush it. Naturally, increased requirements for strength and unsinkability are applied to icebreakers. If you look under the thickened skin compared to a conventional ship, you can see a system of reinforced beams: stringers, frames ... - and the entire hull of the icebreaker is divided by watertight bulkheads into several sealed compartments. In the waterline area, the skin is reinforced with an additional strip - the so-called ice belt. And to overcome the frictional resistance of the hull on the ice, a pneumatic washer device is used, which pumps air bubbles through small holes in the board.
The bevel of the hull contours in the bow, used by the inventor of the icebreaker Britnev, is still used today. Moreover, not only the stem (“nose” of the ship) is sharpened, but also the sternpost, since it is necessary to move in the ice in the “shuttle” way - “back and forth”. It is interesting that initially the Ermak icebreaker had two propellers - in front and behind. Admiral Makarov spied on such a scheme from American small icebreakers that sailed along the Great Lakes. However, the very first collision with the Arctic ice showed that the front propeller in high latitudes is no help, and the icebreaker was remade.
In attack and defense
The action of an icebreaker is by no means limited to a simple crushing of ice, although, of course, the larger part is on top of the ice field, the longer the lever arm and the higher the efficiency of work. Important, as was said, is the shape of the "nose", and the emphasis (thrust force) of the propellers, and the inertial properties of the ship operating in raids.
An icebreaker could be compared to a military unit that has the means and tactics for both defense and offensive. For the offensive, each icebreaker is equipped with a trim system. In a few words, it can be described as two tanks - bow and stern - alternately filled with outboard water. On the first icebreakers, the tanks were connected by a pipe, later each of them was equipped with its own pump.
Having climbed onto the ice field, the icebreaker fills the bow tanks with water and gives additional dynamics to the movement from top to bottom. The alternating filling of the tanks causes it to swing vigorously from bow to stern, as a splitter does when it gets stuck in a log. By pumping out water from the bow tanks and filling the stern tanks, the icebreaker quickly returns to clear water to repeat the attack.
The same system ensures the rocking of the vessel from side to side: additional tanks are located on both sides.
Naturally, all these actions require an energy saturation that is unusual for any other ship. It is not surprising that for a long time the icebreakers could not perform any other marine work - neither cargo nor passenger - except for escorting ships: the entire interior of these "armored safes" was occupied by the engine and fuel supply. Just the main marine specialty of the icebreaker is due to the shape of its hull: it is made wide so that the channel remaining behind it is convenient for the passage of slave ships. The length of the vessel, for better maneuverability, is being tried to be reduced.
The first icebreakers were steam-powered, with coal-fired boilers and steam plants. Coal, which filled almost all the free space in the hold, was usually enough for thirty days. It happened that in the middle of the route, the icebreaker commander informed the caravan that he was stopping the wiring and leaving for the port to replenish fuel supplies.
The next generation were diesel icebreakers, power plants which rotated the rotors of electric generators. The current was supplied to electric motors that set in motion propeller shaft with screw.
But to conquer the Arctic ice, more and more power was required, and diesel icebreakers were replaced by nuclear icebreakers, the reactors of which drive steam generators, steam turbines ensure the operation of electric generators, and electric motors - propeller shafts with screws. In the holds of nuclear-powered ships, the place of fuel was taken by powerful radiation protection systems.
On the edge
One hundred and forty years of the history of icebreakers have changed a lot in their design, most of all their power has increased. If the power of the Ermak engines was 9.5 thousand hp, then the diesel-electric icebreaker Moskva, which went to sea about half a century later, was twice as powerful - 22 thousand hp. Modern nuclear-powered icebreakers of the Taimyr type already harness 50,000 "horses".
Due to the difficulties of their maritime profession, the power of the icebreakers' propulsion systems per ton of displacement is six times higher than that of ocean liners. But even nuclear icebreakers remained qualitatively the same - armored boxes filled with herds of "horses". The business of icebreakers is to break through the ice for the caravans of ordinary tankers and transporters following them. This principle of organizing transportation can be compared with the movement of barges behind a tugboat. Recently, however, self-propelled barges have become more and more in demand, and marine engineers began to think about how to teach transport ships to walk independently in ice.
The idea is not new: back in the 60s of the XIX century, the first Russian iron warship - the armored gunboat "Experience" was tried to be converted according to the project of engineer Euler into the original icebreaker. The “experience” was given a bow ram, several cranes were installed on board for dropping 20-40-pound weights, and “shots” were arranged in the underwater part - poles with explosives mounted on them. However, the "Experience" did not stand the test and was again converted into a gunboat, called the "Mina".
Later, attempts were made to cut the ice with cutters or melt it, but they did not justify themselves (although auxiliary devices for heating the bow of the hull are used on the nuclear icebreakers Arktika and Sibir). And then it was decided to try to change not just the way of breaking ice, but the icebreaker itself, making it not a “cleaver”, but a “blade”. To do this, it was planned to turn the ship into a “catamaran”, two hulls of which would be located one above the other: all cargoes would be placed in the lower, underwater part, and the power plants in the surface, and both parts would be connected with narrow “knives”, inside which would be placed coming from the hull into the body of the loading and unloading pipes. Whether such a transport icebreaker will appear is unknown, but the fact that the Russian icebreaker fleet should continue to develop is beyond doubt: the expanses of the Arctic will always beckon with their riches.
I understand that this is all a large-scale repetition of a huge number of photographs of people who visited the ship on excursions, especially since they drive to the same places. But it was interesting for me to figure it out myself.
This is our nuclear-powered guide:
It was about creating a ship that can sail for a very long time without calling at ports for fuel.
Scientists have calculated that a nuclear-powered icebreaker will consume 45 grams of nuclear fuel per day - as much as will fit in a matchbox. That is why the nuclear-powered ship, having a practically unlimited navigation area, will be able to visit both the Arctic and off the coast of Antarctica in one voyage. For a ship with a nuclear power plant, the distance is not an obstacle.
Initially, we were gathered in this hall for a brief introduction to the tour and divided into two groups.
The Admiralty had considerable experience in the repair and construction of icebreakers. Back in 1928, they overhauled the "grandfather of the icebreaker fleet" - the famous "Ermak".
The construction of icebreakers and icebreaking transport vessels at the plant was associated with a new stage in the development of Soviet shipbuilding - the use of electric welding instead of riveting. The plant staff was one of the initiators of this innovation. New method successfully tested on the construction of icebreakers of the Sedov type. Icebreakers "Okhotsk", "Murman", "Ocean", in the construction of which electric welding was widely used, showed excellent performance; their hull proved to be more durable than other vessels.
Before the Great Patriotic War A large icebreaking and transport vessel "Semyon Dezhnev" was built at the plant, which immediately after sea trials headed for the Arctic to withdraw caravans that had wintered there. Following the "Semyon Dezhnev", the icebreaking transport vessel "Levanevsky" was launched. After the war, the plant built another icebreaker and several self-propelled icebreaker-type ferries.
A large scientific team headed by the outstanding Soviet physicist Academician A.P. Aleksandrov worked on the project. Such prominent specialists as I. I. Afrikantov, A. I. Brandaus, G. A. Gladkov, B. Ya. Gnesin, V. I. Neganov, N. S. Khlopkin, A. N. Stefanovich and Other.
We rise to the floor above
The dimensions of the nuclear-powered ship were chosen taking into account the requirements for the operation of icebreakers in the North and ensuring its best seaworthiness: the icebreaker is 134 m long, 27.6 m wide, and has a shaft power of 44,000 hp. s., displacement 16,000 tons, speed 18 knots in clear water and 2 knots in ice more than 2 m thick.
Long corridors
The designed power of the turboelectric plant is unparalleled. The nuclear-powered icebreaker is twice as powerful as the American icebreaker "Gletcher", which was considered the largest in the world.
When designing the ship's hull, special attention was paid to the shape of the bow, on which the icebreaking qualities of the vessel largely depend. The contours chosen for the nuclear-powered ship, in comparison with existing icebreakers, allow increasing the pressure on the ice. The aft end is designed in such a way that it provides flotation in ice during reverse gear and reliable protection of propellers and rudder from ice impacts.
Canteen:
And the caboose? This is a fully electrified plant with its own bakery, hot food is served by an electric elevator from the kitchen to the dining rooms.
In practice, it was observed that icebreakers sometimes got stuck in the ice not only with their bow or stern, but also with their sides. To avoid this, it was decided to arrange special systems of ballast tanks on the nuclear-powered ship. If water is pumped from the tank of one side to the tank of the other side, then the ship, swaying from side to side, will break and push the ice apart with its sides. The same system of tanks is installed in the bow and stern. And if the icebreaker does not break the ice on the move and its nose gets stuck? Then you can pump water from the stern trim tank to the bow. The pressure on the ice will increase, it will break, and the icebreaker will come out of the ice captivity.
In order to ensure the unsinkability of such a large vessel, if the skin is damaged, it was decided to subdivide the hull into compartments by eleven main transverse watertight bulkheads. When calculating the nuclear icebreaker, the designers ensured the unsinkability of the vessel when the two largest compartments were flooded.
The team of builders of the polar giant was headed by a talented engineer V. I. Chervyakov.
In July 1956, the first section of the nuclear icebreaker's hull was laid down.
To lay out the theoretical drawing of the building on the plaza, a huge area was required - about 2500 square meters. Instead, the breakdown was made on a special shield using a special tool. This allowed to reduce the area for marking. Then template drawings were made, which were photographed on photographic plates. The projection apparatus, in which the negative was placed, reproduced the light contour of the part on the metal. The photo-optical method of marking made it possible to reduce the labor intensity of plaza and marking work by 40%.
Getting into the engine room
The nuclear-powered icebreaker, as the most powerful vessel in the entire icebreaking fleet, is designed to deal with ice in the most difficult conditions; therefore, its body must be especially strong. It was decided to ensure the high strength of the hull using steel new brand. This steel has high impact strength. It welds well and has great resistance to crack propagation at low temperatures.
The design of the hull of the nuclear-powered ship, the system of its set also differed from other icebreakers. The bottom, sides, inner decks, platforms and the upper deck at the extremities were recruited according to the transverse framing system, and the upper deck in the middle part of the icebreaker - along the longitudinal system.
The building, as high as a good five-story house, consisted of sections weighing up to 75 tons. There were about two hundred such large sections.
The assembly and welding of such sections was carried out by the pre-assembly section of the hull shop.
It is interesting to note that the nuclear-powered ship has two power plants capable of providing energy to a city with a population of 300,000. The ship does not need any machinists or stokers: all the work of power plants is automated.
It should be said about the latest propeller motors. These are unique machines made in the USSR for the first time, especially for the nuclear-powered ship. The numbers speak for themselves: the weight of an average engine is 185 tons, the power is almost 20,000 hp. With. The engine had to be delivered to the icebreaker disassembled, in parts. Loading the engine onto the ship presented great difficulties.
They also love cleanliness.
From the pre-assembly section, the finished sections were delivered directly to the slipway. Assemblers and checkers installed them without delay.
During the manufacture of units for the first experimental standard sections, it turned out that the steel sheets from which they should be made weigh 7 tons, and the cranes available at the procurement site had a lifting capacity of only up to 6 tons.
The presses were also underpowered.
One more instructive example of the close community of workers, engineers and scientists should be mentioned.
According to the approved technology, stainless steel structures were welded manually. More than 200 experiments have been carried out; finally, the welding modes were worked out. Five automatic welders replaced 20 manual welders who were transferred to work in other areas.
There was, for example, such a case. Due to the very large dimensions, it was impossible to deliver by railway to the plant fore and sternpost - the main structures of the bow and stern of the vessel. Massive, heavy, weighing 30 and 80 g, they did not fit on any railway platforms. Engineers and workers decided to make the stems directly at the factory by welding their individual parts.
To imagine the complexity of assembling and welding the mounting joints of these stems, suffice it to say that the minimum thickness of the welded parts reached 150 mm. Welding of the stem continued for 15 days in 3 shifts.
While the building was being erected on the slipway, parts, pipelines, and devices were manufactured and assembled in various workshops of the plant. Many of them came from other companies. The main turbogenerators were built at the Kharkov Electromechanical Plant, propeller motors - at the Leningrad Electrosila Plant named after S. M. Kirov. Such electric motors were created in the USSR for the first time.
Steam turbines were assembled in the workshops of the Kirov Plant.
The use of new materials required a change in many of the established technological processes. Pipelines were mounted on the nuclear-powered ship, which were previously connected by soldering.
In collaboration with the specialists of the welding bureau of the plant, the workers of the assembly shop developed and introduced electric arc welding of pipes.
The nuclear-powered ship required several thousand pipes of various lengths and diameters. Experts have calculated that if the pipes are pulled out in one line, their length will be 75 kilometers.
Finally, the time arrived for the completion of the slipway work.
Before the descent, one difficulty arose, then another.
So, it was not easy to install a heavy rudder blade. Putting it in place in the usual way did not allow the complex design of the aft end of the nuclear-powered ship. In addition, by the time the huge part was installed, the upper deck had already been closed. Under these conditions, it was impossible to take risks. We decided to hold a "general rehearsal" - first we put not a real baller, but its "double" - a wooden model of the same dimensions. The "rehearsal" was a success, the calculations were confirmed. Soon, the multi-ton part was quickly brought into place.
The descent of the icebreaker into the water was just around the corner. The large launching weight of the vessel (11 thousand tons) made it difficult to design the launching device, although specialists were engaged in this device almost from the moment the first sections were laid on the slipway.
According to calculations design organization, in order to launch the icebreaker "Lenin" into the water, it was necessary to lengthen the underwater part of the launch tracks and deepen the bottom behind the slipway pit.
A group of employees of the design bureau of the plant and the hull shop developed a more advanced trigger device compared to the original project.
For the first time in the practice of domestic shipbuilding, a spherical wooden rotary device and a number of other new design solutions were used.
To reduce the launch weight, ensure greater stability when launching and braking a vessel that has descended from the slipway into the water, special pontoons were brought under the stern and bow.
The icebreaker's hull was freed from scaffolding. Surrounded by portal cranes, sparkling with fresh paint, he was ready to set off on his first short journey - to the water surface of the Neva.
Move on
We're going down
. . . PJ. To an uninitiated person, these three letters do not say anything. PEV - post of energy and survivability - the brain of icebreaker control. From here, with the help of automatic devices, operating engineers - people of a new profession in the fleet - can remotely control the operation of the steam generator unit. From here, the necessary mode of operation of the "heart" of the nuclear-powered ship - the reactors - is maintained.
Experienced sailors, who have been sailing on ships of various types for many years, are surprised: PEJ specialists wear snow-white bathrobes over the usual marine uniform.
The post of energy and survivability, as well as the wheelhouse and crew cabins are located in the central superstructure.
And now on to the story:
December 5, 1957 In the morning it was continuously drizzling, with occasional sleet falling. A sharp, gusty wind blew from the bay. But people did not seem to notice the gloomy Leningrad weather. Long before the icebreaker was launched, the platforms around the slipway were filled with people. Many boarded a tanker under construction next door.
Exactly at noon, the nuclear icebreaker "Lenin" anchored in the very place where on the memorable night of October 25, 1917, the "Aurora" - the legendary ship of the October Revolution - stood.
The construction of the nuclear-powered ship entered a new period - its completion afloat began.
The nuclear power plant is the most important section of the icebreaker. The most prominent scientists worked on the design of the reactor. Each of the three reactors is almost 3.5 times more powerful than the reactor of the first in the world nuclear power plant Academy of Sciences of the USSR.
OK-150 "Lenin" (until 1966)
Rated power of the reactor, VMT 3х90
Rated steam capacity, t/h 3х120
Power on propellers, l/s 44,000
The layout of all installations - block. Each unit includes a pressurized water reactor (i.e. water is both a coolant and a neutron moderator), four circulation pumps and four steam generators, volume compensators, an ion exchange filter with a cooler, and other equipment.
The reactor, pumps and steam generators have separate casings and are connected to each other by short pipes of the "pipe in pipe" type. All equipment is located vertically in the caissons of the iron-water protection tank and is closed with small-sized protection blocks, which ensures easy accessibility when repair work Oh.
A nuclear reactor is a technical installation in which a controlled chain reaction of nuclear fission of heavy elements is carried out with the release of nuclear energy. The reactor consists of an active zone and a reflector. The water-to-water reactor - the water in it is both a fast neutron moderator and a cooling and heat exchange medium. The core contains nuclear fuel in a protective coating (fuel elements - fuel elements) and a moderator. The fuel rods, which look like thin rods, are assembled into bundles and enclosed in covers. Such structures are called fuel assemblies of fuel assemblies.
The fuel rods, which look like thin rods, are assembled into bundles and enclosed in covers. Such structures are called fuel assemblies (FA). The reactor core is a set of active parts of fresh fuel assemblies (SFA), which in turn consist of fuel elements (TVEL). 241 STVs are placed in the reactor. The resource of the modern core (2.1-2.3 million MWh) provides the energy needs of the ship with nuclear power plants for 5-6 years. After the energy resource of the core is exhausted, the reactor is recharged.
The reactor vessel with an elliptical bottom is made of low-alloy heat-resistant steel with anti-corrosion hardfacing on the inner surfaces.
The principle of operation of APPU
The thermal scheme of the PPU of a nuclear vessel consists of 4 circuits.
The coolant of the 1st circuit is pumped through the reactor core (water high degree cleaning). Water is heated to 317 degrees, but does not turn into steam, because it is under pressure. From the reactor, the coolant of the 1st circuit enters the steam generator, washing the pipes inside which the water of the 2nd circuit flows, turning into superheated steam. Further, the coolant of the first circuit is again fed into the reactor by the circulation pump.
From the steam generator, superheated steam (coolant of the second circuit) enters the main turbines. Steam parameters before the turbine: pressure - 30 kgf/cm2 (2.9 MPa), temperature - 300 °C. Then the steam condenses, the water passes through the ion-exchange purification system and enters the steam generator again.
Circuit III is intended for cooling the APPU equipment, high-purity water (distillate) is used as a heat carrier. The coolant of the III circuit has a slight radioactivity.
The IV circuit serves to cool the water in the III circuit system, sea water is used as a heat carrier. Also, the IV circuit is used to cool the steam of the II circuit during distributing and cooling down the installation.
APPU is made and placed on the ship in such a way as to ensure protection of the crew and the public from exposure, and environment- from contamination with radioactive substances within the permissible safe limits both during normal operation and in case of accidents of the installation and the ship at the expense of. To this end, four protective barriers between nuclear fuel and the environment have been created on possible routes for the release of radioactive substances:
first - shells fuel cells reactor core;
the second - strong walls of the equipment and pipelines of the primary circuit;
the third is the containment of the reactor plant;
the fourth is a protective fence, the boundaries of which are the longitudinal and transverse bulkheads, the second bottom and the upper deck flooring in the area of the reactor compartment.
Everyone wanted to feel like a little hero :-)))
In 1966, two OK-900s were installed instead of three OK-150s.
OK-900 “Lenin”
Rated power of the reactor, VMT 2x159
Rated steam capacity, t/h 2x220
Power on propellers, l/s 44000
Room in front of the reactor compartment
Windows in the reactor compartment
In February 1965, an accident occurred during scheduled repairs at reactor No. 2 of the Lenin nuclear icebreaker. As a result of operator error, the core was left without water for some time, which caused partial damage to approximately 60% of the fuel assemblies.
With channel-by-channel reloading, only 94 of them were unloaded from the core, the remaining 125 turned out to be unrecoverable. This part was unloaded along with the screen assembly and placed in a special container, which was filled with a hardening mixture based on futurol and then stored onshore for about 2 years.
In August 1967, the reactor compartment with the OK-150 nuclear power plant and its own sealed bulkheads was flooded directly from the Lenin icebreaker through the bottom in the shallow Tsivolki Bay in the northern part of the Novaya Zemlya archipelago at a depth of 40-50 m.
Before the flooding, nuclear fuel was unloaded from the reactors, and their first circuits were washed, drained and sealed. According to the Iceberg Central Design Bureau, the reactors were filled with a hardening mixture based on futurol before being flooded.
A container with 125 spent fuel assemblies filled with Futurol was moved from the shore, placed inside a special pontoon and flooded. By the time of the accident, the ship's nuclear power plant had operated for about 25,000 hours.
After that, ok-150 and were replaced by ok-900
Once again about the principles of work:
How does an icebreaker's nuclear power plant work?
In the reactor, uranium rods are placed in a special order. The system of uranium rods is penetrated by a swarm of neutrons, a kind of "fuse", causing the decay of uranium atoms with the release of a huge amount of thermal energy. The rapid motion of neutrons is tamed by the moderator. Myriads of controlled atomic explosions, caused by a stream of neutrons, occur in the thickness of uranium rods. As a result, a so-called chain reaction is formed.
bw photos are not mine
A feature of the icebreaker's nuclear reactors is that not graphite was used as a neutron moderator, as at the first Soviet nuclear power plant, but distilled water. The uranium rods placed in the reactor are surrounded by the purest water (twice distilled). If you fill a bottle with it to the neck, then it will be absolutely impossible to notice whether water is poured into the bottle or not: the water is so transparent!
In the reactor, water is heated above the melting point of lead - more than 300 degrees. Water at this temperature does not boil because it is under a pressure of 100 atmospheres.
The water in the reactor is radioactive. With the help of pumps, it is driven through a special apparatus-steam generator, where it turns non-radioactive water into steam with its heat. The steam enters a turbine that drives a DC generator. The generator supplies current to the propulsion motors. The exhaust steam is sent to the condenser, where it turns back into water, which is again pumped into the steam generator by a pump. Thus, in a system of complex mechanisms, a kind of water cycle occurs.
B&W photos taken by me from the Internet
The reactors are installed in special metal drums welded into a stainless steel tank. From above, the reactors are closed with lids, under which there are various devices for automatically lifting and moving uranium rods. The entire operation of the reactor is controlled by instruments, and if necessary, "mechanical arms"-manipulators come into action, which can be controlled from a distance, being outside the compartment.
The reactor can be viewed on TV at any time.
Everything that poses a danger with its radioactivity is carefully isolated and located in a special compartment.
The drainage system diverts dangerous liquids to a special tank. There is also a system for trapping air with traces of radioactivity. The air flow from the central compartment is thrown through the main mast to a height of 20 m.
In all corners of the ship, you can see special dosimeters, ready at any time to notify of increased radioactivity. In addition, each crew member is equipped with an individual pocket-type dosimeter. The safe operation of the icebreaker is fully ensured.
The designers of the nuclear-powered ship provided for all sorts of accidents. If one reactor fails, another one will replace it. The same work on the ship can be performed by several groups of identical mechanisms.
This is the basic principle of operation of the entire system of a nuclear power plant.
In the compartment where the reactors are placed, there is a huge number of pipes of complex configurations and large sizes. The pipes had to be connected not as usual, with the help of flanges, but butt-welded with an accuracy of one millimeter.
Simultaneously with the installation of nuclear reactors, the main mechanisms of the engine room were installed at a rapid pace. Steam turbines were mounted here, rotating generators,
on an icebreaker; there are more than five hundred electric motors of different power on the nuclear-powered ship alone!
Corridor in front of the medical center
While the installation of power systems was underway, engineers worked on how to better and faster mount and put into operation the ship's machinery control system.
All management of the complex economy of the icebreaker is carried out automatically, directly from the wheelhouse. From here, the captain can change the operating mode of the propeller engines.
Actually first-aid post: Medical offices - therapeutic, dental X-ray, physiotherapy, operating room? procedures: Yuya as well as a laboratory and a pharmacy are equipped with the latest medical and preventive equipment.
Work related to the assembly and installation of the superstructure of the ship, It was not an easy task: to assemble a huge superstructure weighing about 750 tons. A boat with a water jet, main and foremasts were also built for the icebreaker in the workshop.
The four blocks of the superstructure assembled in the shop were delivered to the icebreaker and installed here by a floating crane.
The icebreaker had to perform a huge amount of insulation work. The area of isolation was about 30,000 m2. New materials were used to isolate the premises. Monthly presented for acceptance of 100-120 rooms.
Mooring trials are the third (after the slipway period and completion afloat) stage of the construction of each vessel.
Prior to the launch of the steam generator plant of the icebreaker, steam had to be supplied from the shore. The device of the steam pipeline was complicated by the lack of special flexible hoses of large cross section. It was not possible to use a steam pipeline from ordinary metal pipes, tightly fixed. Then, at the suggestion of a group of innovators, a special hinged device was used, which ensured a reliable supply of steam through the steam line to the nuclear-powered ship.
The electric fire pumps were launched and tested first, and then the entire fire system. Then, tests of the auxiliary boiler plant began.
The engine started up. The instrument needles flickered. One minute, five, ten. . . The engine works great! And after a while, the installers began to adjust the devices that control the temperature of water and oil.
When testing auxiliary turbogenerators and diesel generators, special devices were needed to allow loading two parallel turbogenerators.
How was the test of turbogenerators?
The main difficulty was that during the work the voltage regulators had to be replaced with new, more advanced ones, which provide automatic voltage maintenance even under conditions of high overload.
Mooring tests continued. In January 1959, turbogenerators with all the mechanisms and automatic machines serving them were adjusted and tested. Simultaneously with the testing of auxiliary turbogenerators, electric pumps, ventilation systems and other equipment were tested.
While the mechanisms were being tested, other work was carried out at full speed.
Successfully fulfilling their obligations, the Admiralty in April completed the testing of all the main turbogenerators and propulsion motors. The test results were excellent. All calculated data made by scientists, designers, designers were confirmed. The first stage of testing the nuclear-powered ship was completed. And finished successfully!
April 1959
The installers of the hold department entered the case.
The first-born of the Soviet nuclear fleet, the Lenin icebreaker is a vessel perfectly equipped with all means of modern radio communication, location installations, and the latest navigation equipment. The icebreaker is equipped with two radars - short-range and long-range. The first is designed to solve operational navigation problems, the second - to monitor the environment and the helicopter. In addition, it must duplicate the short-range locator in conditions of snowfall or rain.
The equipment located in the bow and stern radio rooms will ensure reliable communication with the shore, with other ships and aircraft. Internal communication is carried out by an automatic telephone exchange with 100 numbers, separate telephones in various rooms, as well as a powerful general ship radio broadcasting network.
Work on the installation and adjustment of communication facilities was carried out by special teams of installers.
Responsible work was carried out by electricians to put into operation electrical and radio equipment and various devices in the wheelhouse.
The nuclear-powered ship will be able to sail for a long time without calling at ports. So it is very important where and how the crew will live. That is why, when creating the icebreaker project, special attention was paid to the living conditions of the team.
More living rooms
. .. Long bright corridors. Along them are sailor cabins, mostly single, less often for two people. During the day, one of the beds is removed into a niche, the other turns into a sofa. In the cabin, opposite the sofa, there is a desk and a swivel chair. Above the table is a clock and a shelf for books. Nearby are wardrobes for clothes and personal belongings.
In a small entrance vestibule there is another closet - especially for outerwear. A mirror is fixed above a small faience washbasin. Hot and cold water in the taps - around the clock. In short, a cozy modern small-sized apartment.
All rooms have fluorescent lighting. The electrical wiring is hidden under the lining, it is not visible. Milky glass screens cover fluorescent lamps from harsh direct rays. Each bed has a small lamp that gives a soft pink light. After labor day, having come to his cozy cabin, the sailor will be able to have a great rest, read, listen to the radio, music ...
There are also household workshops on the icebreaker - a shoemaker's and a tailor's workshop; there is a hairdressing salon, a mechanical laundry, baths, showers.
We return to the central staircase
We go up to the captain's cabin
More than one and a half thousand cabinets, armchairs, sofas, shelves took their places in the cabins and service rooms. True, all this was made not only by the woodworkers of the Admiralty plant, but also by the workers of the furniture factory No. 3, the plant named after A. Zhdanov, and the Intourist factory. The Admiralty also made 60 separate sets of furniture, as well as various wardrobes, beds, tables, hanging cabinets and bedside tables - beautiful solid furniture.
