The VVER-1000R installation is a reactor with a circulation circuit, a pressure compensation system, and an emergency cooling unit. The main circulation circuit includes a reactor and four working loops, each of which is equipped with a horizontal type steam generator, a circulation pump, and a Du 850 pipeline (with a nominal diameter of 850 mm). Fuel energy is diverted from the core using a coolant pumped by the main circulation pumps. Then, the heated carrier is transported by pipeline to the steam generators, where it transfers heat to the liquid of the second circuit, and then returns to the reactor under the influence of the pump. Dry saturated steam from the second circuit is transferred to the turbine.
VVER-1000 reactor
This element is designed to generate thermal energy in the design of the installation of a steam-conducting nuclear power plant with a capacity of one thousand MW unit. In fact, the reactor is an energy nuclear element of a hull configuration with thermal neutrons, as well as ordinary water, which serves as a coolant and moderator.
The design of the VVER-1000 reactor includes a housing with a shaft, a partition, an active part and a safety pipe assembly. The upper part of the housing is equipped with a control and protection unit. The coolant is transported to the reactor through the four lower nozzles, and flows down the annular gap. Further, his path is the active zone, where he enters through the bottom of the mine. There, the coolant is heated from the generated heat of the nuclear reaction and is removed from the reactor by means of the upper nozzles and shaft openings. The power of the unit is adjusted by moving in the active compartment of the regulatory bodies (a set of absorbing rods hanging on special traverses).
Housing
This part of the VVER-100 reactor serves to accommodate the core and devices inside the vessel. A skeleton is a vertical tank in the shape of a cylinder, consists of a flange, a block of pipes, a shell, a cylinder with an elliptical bottom.
The flange has 54 holes with thread size M170 * 6. They are designed for studs and wedge-shaped grooves, used for mounting rod sealing gaskets of the main connector. The hull of the VVER-1000 is equipped with two rows of nozzles. In the main directions of the upper and lower tiers, analogues of size DN 300 are provided. They serve to dock the emergency cooling system of the active compartment, as well as several nozzles of DN 250, which output impulse lines of measuring instruments.
The case is made of alloy steel. The inside is coated with a special corrosion resistant coating. The skeleton weighs 323 tons. The unit is transported by rail or sea.
Mine
This part of the VVER-1000 is focused on creating a flow of a thermal carrier; it belongs to the component part of protecting the metal casing from neutron fluxes and gamma radiation emitted from the active part. In addition, the shaft serves as a support.
Structurally, the part is a shell of a cylindrical configuration of a welded type. In the upper part of the device is a flange that serves as a support for the inner shoulder of the core. Bottom provides a perforated bottom type. In the bottom there are supporting parts for fuel cartridge elements of the active compartment. The separation of the hot and cold coolant flow from the outside is ensured by an annular thickening aggregating with a separation analog of the VVER-1000 reactor vessel.
Below the shaft from vibration is fixed by dowels, which are welded to the vibration damper, are included in the vertical design nests. The cover of the upper block is held from the ascent by means of a tubular elastic holder. Structurally, the shaft is made in such a way that makes it possible to extract it from the core of the reactor in cases with fuel overloads. This is necessary to inspect the insides of the nozzles and the housing. The weight of the shaft made of anti-corrosion steel is 69.5 tons.
Fence
This part serves to configure the area of the emissions of the energy formation and organize the transportation of the thermal carrier through the core. An additional functional of the partition is the protection of the metal of the core from the effects of aggressive radiation.
The element is a cylinder with thick walls and five forged rings. The inner part of the block duplicates the contour of the active compartment. The cooling unit is provided by vertical channels provided in the rings of the partition. They are connected mechanically, the lower element is fixed on the faceted shaft of the shaft, and the upper ring is centered in relation to the cylinder of the shaft using welded dowels. A fence is made of durable anti-corrosion steel, its weight is 35 tons.
VVER-1000 steam generator
This element is a single-case heat exchanger with a pair of circuits. It has a horizontal arrangement, equipped with a submersible set of pipes. The design of the steam generator includes a skeleton, an inlet and outlet manifold, a tube bundle of heat exchange, a collector for distributing nutrient fluid, a separator, a steam outlet unit, a drainage and purge unit.
The unit is designed to function as part of both circuits; it produces dry saturated steam from the water of the second cycle. The material of manufacture is alloy steel, inside protected by a special cladding resistant to corrosion processes.
Technical plan options
Characteristics of the VVER-1000 steam generator:
- The thermal capacity indicator is 750 MW.
- Steam productivity - 1469 t / h.
- Nominal pressure in the secondary circuit is 6.3 MPa.
- Heat exchange surface - 6115 m.
- The consumption of thermal carrier is 20,000 m / h.
- The moisture content in the steam at the outlet is 0.2%.
- The volume of the skeleton is 160 m.
- Weight - 204.7 tons.
Pressure compensator
The part is a high pressure tank, equipped with built-in electric heater blocks. In working condition, the tank is filled with water and steam. The unit is designed to operate in conjunction with the system of the first reactor cycle, maintains pressure in the circuit during normal operation and limits fluctuations in the event of a transition to emergency mode.
The pressure in the compensator of the VVER-1000 NPP is created and fixed by means of adjustable fluid heating, which is provided by electric heaters. The compensator provides a system for injecting water into the steam compartment from the cold parts of the primary circuit by means of a spray device. This avoids the increase in pressure above the calculated indicators. The compensator body is made of alloy steel with internal protective fusion.
Other components
The scheme of the VVER-1000 reactor is presented below. It includes several more units, namely:
- Ion exchange filter. It is filled with special resins, made in the form of a vertical high-pressure tank. The element serves to clean the thermal carrier from radioactive particles, insoluble corrosive inclusions. The filter housing is made of anti-corrosion steel.
- Emergency zone cooling tank. This is a vertical high-pressure tank, used to provide emergency filling of the active part of the reactor with coolant in the event of an emergency. The system includes four autonomous containers connected to the core of the reactor via pipelines.
In addition, the design includes a step-by-step electromagnetic drive with a block of electromagnets, the upper block (serves to create a closed volume and working pressure of the reactor), a protective tube assembly.