Carly Wood Valves April 14th, 2019 - 12:27:41
In standard valves, when it is given a command to open to a certain point, there is no feedback to verify that the valve has opened to that position. With a valve positioner, the command is given and the valve positioner reads the opening, verifying the position and readjusting until it gets it to the exact position needed. This allows for great precision in the adjustment.
The sometimes highly specialized working environments in which manual operated sleeve valves must perform can include differing temperatures ranging from -60°F to 300°F. The sleeves themselves can be manufactured from natural rubber or a compounded elastomer, which provide specific operational capabilities. Control sleeve valves are recognized for their excellent abrasion resistance and ability to process animal and vegetable fats.
There are three kinds of this valve. There is a valve that is high in performance, which is reliable in functioning under higher pressure that can withstand as high as 725 PSI and temperature applications. Next is the resilient valve, it has an elastic rubber seat and could work up to the pressure of 232 PSI. Lastly, the tricentric valve that is commonly adorned with a seating made of metal and it can function up to the pressure of 1450 PSI.
Valves are either made of plastic or metal and can be controlled either by handles, levers, pedals and wheels or can be controlled automatically. Generally, the exterior parts are either metal or plastic and are called seat and the inner part generally has plastic and rubber valves for an effective control of the flow of fluids. Body is the inner part of the valve that fits on the seat and controls the flow by opening and closing either partially or wholly depending upon the requirement of the flow rate.
Customers wanting the best in Needle Valves need look no further than Swagelok to meet all their needs. Swagelok Needle Valves are used in flow metering applications, where a constant, calibrated flow must be maintained. A Needle Valve has a long tapered point at the end of the valve stem that is lowered through the seat to restrict or block flow, as required, and a needle-shaped plunger on the end of the screw which exactly fits the point. Fluid flowing through the valve turns at 90 degrees, and passes through the orifice that is the seat for a rod with a cone shaped tip. The finely threaded stem, and large seat area allow for the precise calibration of resistance to flow. As the plunger is retracted, flow between is possible - until the plunger is completely retracted, fluid flow is impeded.
Two thousands years ago, the Chinese people applied the bamboo trunk and wooden plug into water pipeline. Then later they applied the sluice into the irrigational canal, the plate check valve into bellows for smelting and so on. With the development of smelting process and hydraulic machinery, the plug valve made of brass and lead appeared in Europe. Besides, with the wide application of boiler, in 1681 the safe valve with lever and heavy bob came into the world. Before the invention of the Watt steam engine, the plug valve and check valve were the most important valves. The steam engine leaded the valve into a new field namely mechanical industry.