About a storage tank

Storage tank are containers that hold liquids, compressed gases (gas tank) or mediums used for the short- or long-term storage of heat or cold. The term can be used for reservoirs (artificial lakes and ponds), and for manufactured containers. The usage of the word tank for reservoirs is uncommon in American English but is moderately common in British English. In other countries, the term tends to refer only to artificial containers.

In the USA, storage tank operate under no (or very little) pressure, distinguishing them from pressure vessels. Storage tank are often cylindrical in shape, perpendicular to the ground with flat bottoms, and a fixed or floating roof. There are usually many environmental regulations applied to the design and operation of storage tank, often depending on the nature of the fluid contained within. Above ground storage tank (AST) differ from underground (UST)steel tank in the kinds of regulations that are applied.

Reservoirs can be covered, in which case they may be called covered or underground storage tank or reservoirs. Covered water tanks are common in urban areas.

Storage tank are available in many shapes: vertical and horizontal cylindrical; open top and closed top; flat bottom, cone bottom, slope bottom and dish bottom. Large tanks tend to be vertical cylindrical, or to have rounded corners transition from vertical side wall to bottom profile, to easier withstand hydraulic hydrostatically induced pressure of contained liquid. Most container tanks for handling liquids during transportation are designed to handle varying degrees of pressure.

A large storage tank is sometimes mounted on a lorry (truck) or on an articulated lorry trailer, which is then called a tanker.

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For the ball valve used in toilet tanks

A ball valve is a form of quarter-turn valve which uses a hollow, perforated and pivoting ball (called a "floating ball") to control flow through it. It is open when the ball's hole is in line with the flow and closed when it is pivoted 90-degrees by the valve handle. The handle lies flat in alignment with the flow when open, and is perpendicular to it when closed, making for easy visual confirmation of the valve's status.

Ball valve are durable, performing well after many cycles, and reliable, closing securely even after long periods of disuse. These qualities make them an excellent choice for shutoff applications, where they are often preferred to gates and globe valve, but they lack their fine control in throttling applications.

The ball valve's ease of operation, repair, and versatility lend it to extensive industrial use, supporting pressures up to 1000 bar and temperatures up to 752 °F (500 °C), depending on design and materials used. Sizes typically range from 0.2 to 48 inches (0.5 cm to 121 cm). Valve bodies are made of metal, plastic, or metal with a ceramic; floating balls are often chrome plated for durability.

A ball valve should not be confused with a "ball-check valve", a type of check valve that uses a solid ball to prevent undesired backflow.

Other types of quarter-turn valves include the butterfly valve and plug valve.

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Structure and principles of the Scrap shredder

Scrap shredder is used to destroy the paper shredding machines, obsolete files in order to achieve the purpose of confidentiality, the paper should be divided into many small pieces of paper.

Now scrap shredder, in addition to paper handling, you can also cut a credit card, CD-RO and scrap metal shearsand .

Structure and working principle of the scrap shredder: scrap shredder has two main components "Cutter" and "electric motor", between the belt and gear to make it through tightly connected together, the motor drive belts, gears, the energy transmitted to the cutter, and the cutter by turning with sharp metal corners to paper shredding.

Some scrap shredder on the market can choose two or more shredding method. Shredding different ways for different occasions, if the case is of general office segment is selected, granular, filamentous, strip it. But if it is used in some of the relatively high confidentiality requirements of the occasion it must use foam-like. The current four-way knife consisting of shredding is the most advanced way of working, shredding paper grain neat neat, can achieve the effect of confidentiality.

Cutting principle shredder blades or knives have been misplaced placed in the role of the power source will tear the paper. If the tool or blade is provided with a tip, the shredding effect with block or granular, or if the tool does not set the blade tip, the effect of the strip.

With the current development of the scrap shredder, according to the use of objects, use a different environment, divided into: hand-cranked shredders, shredder desktop, small personal / home shredders, office shredders medium, large work pieces machine several. is used to destroy the paper shredding machines, obsolete files in order to achieve the purpose of confidentiality, the paper should be divided into many small pieces of paper.

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Marine pump function and classification

Marine pump is a liquid fluid energy machinery. Not only to transport liquid pump, more important is the displacement and pressure to meet work requirements. Since transferring tasks vary, therefore, according to the working principle of distinction, reciprocating pumps, rotary pumps,centrifugal pumps,windlass and jet pumps and other four. Liquid always flows downhill, to make it flow uphill, it must be liquid acting to get some energy, a pressure forcing the liquid to go uphill. A mechanical pump is a certain energy to the liquid, which is a source of energy by the prime mover. Fluid pumps can transport liquids, mainly because it constantly absorbing liquid discharge liquid. The liquid is sucked by the pump pressure is both a vacuum pump and the pump outer atmospheric pressure difference. The higher the vacuum, the more the pressure, the stronger the pump suction. There is no vacuum, pressure is zero, the pump can not suck the liquid.

By Application: transport diesel engine, the required boiler fuel, lubricating oil, power oil, cooling water, makeup water; daily delivery of fresh water needed for the crew and passengers of life, health and water; safe navigation of ships needed to transport ballast water, fire water, bilge water.
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About the mechanical device used in construction

A modern diesel hammer is a very large two-stroke diesel engine. The weight is the piston, and the apparatus which connects to the top of the pile is the cylinder. Piledriving is started by having the weight raised by auxiliary means — usually a cable from the crane holding the pile driver — which draws air into the cylinder. Diesel fuel is added/injected into the cylinder. The weight is dropped, using a quick-release. The weight of the piston compresses the air/fuel mixture, heating it to the ignition point of diesel fuel. The mixture ignites, transferring the energy of the falling weight to the pile head, and driving the weight back up. The rising weight draws in fresh air, and the cycle starts over until the fuel runs out or is stopped by the pile driver.

From an army manual on pile driving hammers: The initial start up of the hammer requires the piston (ram) to be raised to a point where the trip automatically releases the piston, allowing it to fall by gravity. As the piston falls, it activates the fuel pump, which discharges a metered amount of fuel into the ball pan of the impact block. The falling piston also blocks the exhaust ports, and compression of fuel trapped in the cylinder begins. The compressed air exerts a pre-load force to hold the impact block firmly against the drive cap and pile. At the bottom of the compression stroke, the piston strikes the impact block, atomizing the fuel and starting the pile on its downward movement. In the instant after the piston strikes, the atomized fuel ignites, and the resulting explosion exerts an even greater force on the already moving pile, driving it further into the ground. The reaction of the explosion rebounding from the resistance of the pile drives the piston upward. As the piston rises, the exhaust ports open, releasing the gases and force of the explosion into the atmosphere. After the piston stops its upward movement, it again falls by gravity to start another cycle.
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