Have an idea of ball valve

Valves are used to control the flow of gases, liquids and granular solids. They come in many types, sizes, materials, pressure and temperature ratings, and means of actuation. Gate valves and ball valves are two distinct members of the valve family, and are generally used for two different types of flow control.
A ball valve, one type of quarter turn valve, is quite literally a ball placed in a passageway through which fluid flows. The ball has a hole through it, by which the valve opens and closes. When the ball is positioned so that the hole runs the same direction as the passageway, the fluid simply flows through it, and the valve is open. The ball can also be positioned so that the hole is perpendicular to the passageway so that the fluid cannot pass through, and the valve is closed. It is controlled from the outside, often with a handle that is turned back and forth to open and close the valve.
Most ball valves can readily withstand the heat of a propane torch. However, if you are concerned about overheating and damaging the valve, you may wrap a wet rag around the body of the valve to keep it cool.
There are three different types of ball valve. A full port valve offers no flow restriction, which means that when it is open, the liquid can flow freely through it. This is achieved by making the ball larger than the passage size, so that the hole can be the same size as the passage. A standard port ball valve does not have an oversized ball, and as a result, the hole is one size smaller than the passageway. This creates a small amount of flow restriction as the fluid passes through. A reduced port valve, on the other hand, has an smaller ball and an even smaller hole, which creates significant flow restriction as the fluid passes through it.
The forged body ball valve provides extended service life and resists failure caused by severe temperature applications. Optimum flow design assures maximum system efficiency. Highly inert PTFE seats and seals provide resistance to chemical corrosion. Parker also provides a blow-out proof stem, chrome plated brass ball and a specially designed handle enabling increased turning leverage for ease of opening and closing. Parker’s ball valve can be readily identified assuring high quality engineering and reliability.
Ball valves are commonly used in plumbing. They are installed in the hot and cold water copper lines so if you have to do a repair job like changing the faucets on a sink or taking out a sink to put a new one in, you don't have to turn off the water to the entire house. You just turn off the ball valve on the water lines leading to the work project.The handle of the valve is connected to an internal ball that has a hole running through it. When the valve is in the open position the hole in the ball is lined up with the opening in the copper pipes on either side of it. When the ball valve is in the closed position the holes disappear from in front of the pipe openings and no water can flow through. Soldering in a ball valve is no different from soldering a regular copper joint. Here is how to solder in a ball valve on a new copper water pipe installation.
Ball valves can be full port or reduced port. Full port means the ball is oversized and allows for full flow; reduced port means the ball is roughly the same size as the inner diameter of the valve and restricts flow. Plug valves are mostly full port.
Edit by http://www.cnhanjoy.com

Centrifugal pump

A centrifugal pump converts the input power to kinetic energy in the liquid by accelerating the liquid by a revolving device - an impeller. The most common type is the volute pump. Fluid enters the pump through the eye of the impeller which rotates at high speed. The fluid is accelerated radially outward from the pump chasing. A vacuum is created at the impellers eye that continuously draws more fluid into the pump.
Centrifugal pumps are a sub-class of dynamic axisymmetric work-absorbing turbomachinery. Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow. The rotational energy typically comes from an engine or electric motor. The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward into a diffuser or volute chamber (casing), from where it exits.
If the discharge of a centrifugal pump is pointed straight up into the air the fluid will pumped to a certain height -  or head - called the shut off head. This maximum head is mainly determined by the outside diameter of the pump's impeller and the speed of the rotating shaft. The head will change as the capacity of the pump is altered.
Vertical centrifugal pumps are also referred to as cantilever pumps. They utilize a unique shaft and bearing support configuration that allows the volute to hang in the sump while the bearings are outside of the sump. This style of pump uses no stuffing box to seal the shaft but instead utilizes a "throttle Bushing". A common application for this style of pump is in a parts washer.
A machine for moving fluid by accelerating it radially outward. More fluid is moved by centrifugal pumps than by all other types combined. Centrifugal pumps consist basically of one or more rotating impellers in a stationary casing which guides the fluid to and from the impeller or from one impeller to the next in the case of multistage pumps. Impellers may be single suction or double suction.
Circulation pumps are also called circle pumps, they are mostly working for heating systems or mix water systems. Normally, the power of motor is from 75w to 165w, the voltage is 1-230v, 50hz. We have models 25-40, 25-60, 32-80 and so on. The pump head can be two size 130mm and 180mm. And the outlet hole size is normally 1-1/2”. The pump body is cast iron, the impeller is GF-PP, the shalf is stainless steel.
Edit by http://www.cnhanjoy.com