Bluetooth, H700, Dg, Etc ,
It needs additional references or sources for verification. Tagged since December 2008.
30,000m3 BF Gas holder at Rautaruukki Steel in Finland.
Gas holder at West Ham.
The famous Gas holders at The Oval.
A gas holder (or gasholder or gasometer) is a large container where natural gas or town gas is stored near atmospheric pressure at ambient temperatures. The volume of the container follows the quantity of stored gas, with pressure coming from the weight of a movable cap. Typical volumes for large gasometers are about 50,000 cubic metres, with 60 metre diameter structures. Gasometers tend to be used nowadays for balancing purposes (making sure gas pipes can be operated within a safe range of pressures) rather than for actually storing gas for later use.
Contents
1 Other storage systems
2 Advantage of gas holders
3 Gas holder types
4 Europe
5 United States
6 Origin of the name
7 Dry Seal “Wiggins” Type Gasholder
7.1 Main elements
7.1.1 Foundation
7.1.2 Main tank
7.1.3 Piston
7.1.4 Sealing membrane
8 See also
9 External links
10 References
//
Other storage systems
Modern gas containers
Gas more recently was stored in large underground reservoirs such as salt caverns. Nowadays however line-packing is the preferred method.
Throughout the 1960s and 1970s it was thought that gasholders could be replaced with high pressure bullets. However, regulations brought in meant that all new bullets must be built several miles out of towns and cities and the security of storing large amounts of high pressure natural gas above ground made them unpopular with local people and councils. Bullets are gradually being decommissioned. It is also possible to store natural gas in liquid form and this is widely practised throughout the world.
Advantage of gas holders
Gasholders hold a large advantage over other methods of storage. They are the only storage method which keeps the gas at district pressure (the pressure required in local gas mains). Once the District Low Pressure Switch falls, and the booster fans come on, the gas in these holders can be at homes, being used, in a very short space of time. Gas is stored in the holder throughout the day, when little gas is being used. At about 5pm there is a great demand for gas and the holder will come down, supplying the district.
Gas holder types
Gas holder Schematics
There are two basic types of gasholders, rigid waterless and telescoping. Rigid waterless gas holders were a very early design which outwardly showed no sign of expansion or contraction. There are modern versions of the waterless gas holder, e.g. oil-sealed, grease-sealed and “dry seal” (membrane) types .
Telescoping holders fall into two subcategories. The earlier of the telescoping variety were column guided variations and were built in Victorian times In order to guide the telescoping lifts they have an external fixed frame, visible at a fixed height at all times. Spiral guided gasholders were built in the UK up until 1983. These have no frame and each lift is guided by the one below, rotating as it goes up as dictated by helical runners. Both telescoping types use the manometric property of water in order to provide a seal.
Column guided gas holder at Cross Gates, Leeds This is the first of a former twin holder station constructed around 1900
Spiral guided gasholders at the former Meadow Lane Gas Works in Hunslet, Leeds. These were constructed around 1965
Gasometer at Bernau bei Berlin Germany
Europe
Gasometers are often a major part of the skylines of low-rise British cities, due to their large distinctive shape and central location. The pollution associated with gasworks and gas storage makes the land difficult to reclaim for other purposes, but some gasometers, notably in Vienna, have been converted into living space and a shopping mall.
Most British cities will have several gasholders. London, Birmingham, Manchester, Sheffield, Leeds, Newcastle and Glasgow (which has the largest gasometers in the UK) are noted for having many gasholders. Some of these gasometers have become listed buildings. In the past, holder stations would have an operator living on site controlling their movement. However with the process control systems now used on these sites, such an operator is obsolete. The tallest gasometer in Europe is 92 metres tall and is located in Rome.
United States
Gasometers are comparatively rare in the United States. The most notable of these were erected in St. Louis by the Laclede Gas Light Company in the early 1900s. These Gasometers remained in use until the early 2000s when the last one was decommissioned and abandoned in place. The most recently used gasometer in the United States is on the southeast side of Indianapolis but it is to be demolished in 2009 along with the Citizens Energy Group coke plant.
Origin of the name
The term gasometer was originally coined by William Murdoch, the inventor of gas lighting, in the early 1800s. Despite the objections of his associates that his so-called “gazometer” was not a meter but a container, the name was retained and came into general use. The word is also used to describe a gas meter (a meter for measuring the amount of gas flowing through a particular pipe).
Dry Seal “Wiggins” Type Gasholder
A Dry-seal gasholder can be designed to have a gross (geometric) volume ranging from two hundred cubic metres (200 m3) up to one hundred and sixty-five thousand cubic metres (165,000 m3), whilst having a working pressure range between fifteen millibar (15 mbar) and one hundred and fifty millibar (150 mbar). The Dry-seal gasholder is finished with an anti-corrosive treatment to counteract local climatic conditions and also any chemical attack from the stored medium. This anti-corrosive treatment is fully compatible with the sealing membrane and also the environment.
Main elements
The Dry Seal Gasholder has four major elements - the foundation; the main tank; the piston; the sealing membrane. Each of these elements can be divided into various sub-elements and associated accessories.
Foundation
A concrete and hardcore base designed to withstand the weight of the steel gasholder structure constructed upon it and to withstand dynamic climatic conditions acting upon the gasholder etc.
Main tank
The main tank is designed to accommodate the design requirements laid down by the customer and climatic conditions There are three main sub-elements to the tank:
Tank bottomThe tank bottom forms a gas tight seal against the foundation and is “coned up” to facilitate drainage to the periphery. The bottom is covered with steel plates. The outer annular plates are butt welded against backing strips, whilst the infill plates are lap welded on the top side only. Welded to the bottom infill plates is the:
Piston support structureWhen the piston is depressurised it rests on a steel framework which is welded to the bottom plates.
Tank shellThe shell of the tank is designed to accommodate the imposed loads and the general data supplied by the client. The shell is of butt-welded design and is gas tight for approximately 40% of its lower vertical height (known as the gas space) at which point the seal angle is located. The remaining upper 60% (known as the air space) of the shell has in it various apertures for access and ventilation. Attached to the shell are various accessories:
Staircase towerFor external access to the roof of the gasholder and also incorporates access to the inside of the gasholder via the shell access doors. A locked safety gate is usually located at the base of the staircase to prevent any unauthorised access to the…
To get More information , you can visit some products about
cordless answering phone,
motorolla razr,
reconditioned mobiles,
cheap gsm phones,
.
The Bluetooth, H700, Dg, Etc products should be show more here!
