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Pneumatic Non-return Valve
{{unreferenced, date=August 2009 Pneumatic non-return valves are used where a normal non-return valve would be ineffective. This is for example where there is a risk of flood water entering a site but an equal risk of pollution or a chemical spills leaving a site and polluting the environment. Pneumatic non-return valves are installed below ground and can be used to pneumatically lock the non-return valve closed thus containing a site in the event of a spill. It is common practice to lock sites using pneumatic non-return valves during the loading or transferring of chemicals or hazardous waste. Pneumatic non-return valves have a longer service life when compared to pneumatic bladder A pneumatic bladder is an inflatable (pneumatic) bag technology with many applications. Emergency management applications Pneumatic bladders are used to seal drains and ducts to contain chemical spills or gases. Pneumatic bladders are often used f ... systems. Valves Environmental protection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Check Valve
A check valve, non-return valve, reflux valve, retention valve, foot valve, or one-way valve is a valve that normally allows fluid (liquid or gas) to flow through it in only one direction. Check valves are two-port valves, meaning they have two openings in the body, one for fluid to enter and the other for fluid to leave. There are various types of check valves used in a wide variety of applications. Check valves are often part of common household items. Although they are available in a wide range of sizes and costs, check valves generally are very small, simple, and inexpensive. Check valves work automatically and most are not controlled by a person or any external control; accordingly, most do not have any valve handle or stem. The bodies (external shells) of most check valves are made of plastic or metal. An important concept in check valves is the cracking pressure which is the minimum differential upstream pressure between inlet and outlet at which the valve will operate. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood Water
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding, for example land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees, and larger environmental issues such as climate change and sea level rise. In particular climate change's increased rainfall and extreme weather events increases the severity of other causes for flooding, resulting in more intense floods and increased flood risk. Flooding may occur as an overflow of water from water bodies, such as a river, lake, or ocean, in which the water overtops or breaks levees, resulting in some of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Spills
A chemical accident is the unintentional release of one or more chemical hazard substances which could harm human health and the environment. Such events include fires, explosions, leakages or release of toxic or hazardous materials that can cause people illness, injury, or disability. Chemical accident can be caused by natural disaster, or accidental human error, or deliberate move to cause chaos and destructions for personal gain. While chemical accidents may occur whenever toxic materials are stored, transported or used, the most severe are industrial accidents, involving major chemical manufacturing and storage facilities. Examples The most dangerous chemical accident recorded in history was the 1984 Bhopal gas tragedy in India, in which more than 3,000 people died after a highly toxic vapor, methyl isocyanate, was released at a Union Carbide Pesticides factory. The release happened after the storage tank safety valve had failed to contain the excess pressure created by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumatic Bladder
A pneumatic bladder is an inflatable (pneumatic) bag technology with many applications. Emergency management applications Pneumatic bladders are used to seal drains and ducts to contain chemical spills or gases. Pneumatic bladders are often used for the containment of chemical spills, oil spills or fire water on water to prevent them from entering the environment, usually in the form of booms. Marine applications The Reef Ball Foundation uses a pneumatic bladder technology to float an artificial coral reef ("reef ball") into location, then deflate the bladder to sink the reef to the bottom. Other applications Pneumatic bladders, known as dunnage bags, are used to stabilize cargo within a container. Pneumatic bladders are used in medical research. Leading edge inflatable kites use pneumatic bladders restrained by a fabric case; the bladder is selected slightly larger than the case, so that at operational inflation the bladder is not stressed while the case defines the final ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valves
A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings, but are usually discussed as a separate category. In an open valve, fluid flows in a direction from higher pressure to lower pressure. The word is derived from the Latin ''valva'', the moving part of a door, in turn from ''volvere'', to turn, roll. The simplest, and very ancient, valve is simply a freely hinged flap which swings down to obstruct fluid (gas or liquid) flow in one direction, but is pushed up by the flow itself when the flow is moving in the opposite direction. This is called a check valve, as it prevents or "checks" the flow in one direction. Modern control valves may regulate pressure or flow downstream and operate on sophisticated automation systems. Valves have many uses, including controlling water for irrigation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
