An internal pressurization system allows for a different pressure internally than externally. The Components There are three components in a pressure vessel that are considered to be basic — the shell casing, necessary attachments and a base. The other components are considered to mainly include the nozzle and the head.
Classification of nuclear power reactors[ edit ] A typical RPV Not all power reactors have a reactor pressure vessel. Power reactors are generally classified by the type of coolant rather than by the configuration of the reactor vessel used to contain the coolant.
Light-water reactor - Includes the pressurized water reactor and the boiling water reactor. Most nuclear power reactors are of this type. Graphite-moderated reactor - Includes the Chernobyl reactor RBMKwhich has a highly unusual reactor configuration compared to the vast majority of nuclear power plants in Russia and around the world.
Gas cooled thermal reactor - Includes the Advanced Gas-cooled Reactorthe gas cooled fast breeder reactor, and the high temperature gas cooled reactor. An example of a gas cooled reactor is the British Magnox. Pressurized heavy-water reactor - utilizes heavy water, or water with a higher than normal proportion of the hydrogen isotope deuterium, in some manner.
However, D2O heavy water is more expensive and may be used as a main component, but not necessarily as a coolant in this case.
Liquid metal cooled reactor - utilizes a liquid metal, such as sodium or a lead - bismuth alloy to cool the reactor core. Molten salt reactor - salts, typically fluorides of the alkali metals and of Pressure vessel components alkali Pressure vessel components metals, are used as the coolant.
Operation is similar to metal-cooled reactors with high temperatures and low pressures, reducing pressure exerted on the reactor vessel versus water or steam-cooled designs. Of the main classes of reactor with a pressure vessel, the pressurized water reactor is unique in that the pressure vessel suffers significant neutron irradiation called fluence during operation, and may become brittle over time as a result.
In particular, the larger pressure vessel of the boiling water reactor is better shielded from the neutron flux, so although more expensive to manufacture in the first place because of this extra size, it has an advantage in not needing annealing to extend its life.
Annealing of pressurized water reactor vessels to extend their working life is a complex and high-value technology being actively developed by both nuclear service providers AREVA and operators of pressurized water reactors.
Components of a pressurized water reactor pressure vessel[ edit ] A reactor vessel body and vessel head being shipped to Dresden Generating Station All pressurized water reactor pressure vessels share some features regardless of the particular design.
Reactor vessel body[ edit ] The reactor vessel body is the largest component and is designed to contain the fuel assembly, coolant, and fittings to support coolant flow and support structures. It is usually cylindrical in shape and is open at the top to allow the fuel to be loaded.
Reactor vessel head[ edit ] A reactor vessel head for a pressurized water reactor This structure is attached to the top of the reactor vessel body. It contains penetrations to allow the control rod driving mechanism to attach to the control rods in the fuel assembly.
The coolant level measurement probe also enters the vessel through the reactor vessel head. Fuel assembly[ edit ] The fuel assembly of nuclear fuel usually consisting of uranium or uranium—plutonium mixes.
It is usually a rectangular block of gridded fuel rods. Neutron reflector or absorber[ edit ] Protecting the inside of the vessel from fast neutron escaping from the fuel assembly is a cylindrical shield wrapped around the fuel assembly.
Reflectors send the neutrons back into the fuel assembly to better utilize the fuel. The main purpose though is to protect the vessel from fast neutron induced damage that can make the vessel brittle and reduce its useful life. Materials for reactor pressure vessels[ edit ] The RPV provides a critical role in safety of the PWR reactor and the materials used must be able to contain the reactor core at elevated temperatures and pressures.
The stainless steel cladding is primarily used in locations that come into contact with coolant in order to minimize corrosion. Both materials have main alloying elements of nickel, manganese, molybdenum, and silicon, but the latter also includes 0. Due to harsh conditions, the RPV cylinder shell material is often the lifetime-limiting component for a nuclear reactor.
Radiation damage in metals and alloys[ edit ] Due to the nature of nuclear energy generation, the materials used in the RPV are constantly bombarded by high-energy particles.
These particles can either be neutrons or fragments of an atom created by a fission event. When this happens, this primary "knock-on" atom PKA that was displaced and the energetic particle may rebound and collide with other atoms in the lattice.
This creates a chain reaction that can cause many atoms to be displaced from their original position.A pressure vessel has a variety of parts for the pressure to be held in place.
See the components used by pressure vessel components manufacturers to support the pressure vessel. A tubular heat exchanger exemplifies many aspects of the challenge in designing a pressure vessel. High or very low operating pressures and temperatures, combined with sharp temperature gradients, and large differences in the stiffnesses of adjoining parts, are amongst the legion of conditions that And Pressure Vessel Components.
. Alloy Products Corp produces ASME stainless steel pressure vessels as well as customized and general purpose vessels that are used in a variety of sanitary, industrial and general purpose applications.
Where applicable, pressure vessel heads, shells and other components are supplied with a Certificate of Compliance showing type, size, material type, order numbers, heat numbers and minimum thicknesses.
Among the components subjected to stress analysis are pressure vessel branches, pressure vessel ends, local attachments, and flanges. Smooth and mitered pipe bends, externally pressurized vessels, and creep effects in structures are also benjaminpohle.com Edition: 1st Edition.
Stainless Steel Tank Components & Pressure Vessel Parts. Every component counts. As our highest goal, HOLLOWAY AMERICA is dedicated to providing the highest quality vessel components in the industry. Why? Because we use them ourselves, in the manufacture of our very own Stainless Tanks and Pressure Vessels.