Comparative characteristics of valves

Valves designed to control fluid flow to various standpipes devices such as mixers, as well as different sanitation facilities, including dishwashers and washing machines.Overrides path and it is to some sections of the pipeline, for which you want to control.Modern pipe systems are used as shut-off valves various valves and ball valves.What are the comparative characteristics of both types of shut-off valves?We analyze in this article.

Features and Specifications valves

use valves as shut-off valves is possible at all, without exception, sections of the pipeline, where it is necessary to completely cover the water or gas flow.Their normal state is open.The design features of these devices are that they are setting into place is carried oriented.It means that their mounting on the direction of movement of water in the system.In any case the valve is an arrow that indicates the direction in which the fluid stream.Install the valve should be in that direction, otherwise it will fail.

Structurally similar to conventional valve head parts.Its locking mechanism is in the form of a threaded rod provided with a valve at its end.Flywheel outputted to the outside is connected to this rod, so that during rotation of the reciprocation motion of the rod.When this valve increases or reduces the through-hole of the locking device.Complete cessation of the flow of water occurs only in the final saddle valve overlap edge of the hole.Fixed to the valve paronitovye or rubber gasket provides locking seal.

valves are old enough devices has proven its reliability for decades.These advantages include:

• high reliability, which is ensured even under conditions of significant contamination of the hydraulic fluid.Even if water is present in a large number of insoluble impurities such as sand, rust or silt, the device performs its locking function properly.
• Excellent maintainability.Often, to eliminate the leak occurred in the valve is sufficient to replace the gasket.

note and obvious disadvantages of such a device:

• Too long operation sooner or later leads to a degree of corrosion damage the stem, it ceases to perform its task properly.This applies especially to the products, which components are made of different metals or alloys (often brass and steel).At the junction of the two metals because an electric potential of corrosion processes occur much faster.
• too frequent need to replace the rubber gaskets.
• To completely stop the flow of the device have to rotate the flywheel for a long time.

Whatever it was, the valves are commonly used not only in the domestic lines but also in industrial plants.Due to the simplicity of the device, they have a relatively small cost.

Features and characteristics of ball valves

Using cranes as shut-off valves widespread together with valves.They are cylindrical, cone and ball, due to the shape of your gate.The main locking element in the taps is conical or cylindrical plug, which is very close to a ground surface inside the faucet.

device plug valve

In it, sealing it landing in the housing as may act and ball, on which there are two PTFE sealing ring.As the tube and ball are provided with a through bore through which the water flows freely in the open position, as it is located along the flow.If the ball or plug to rotate 90 degrees, the hole will rise across the current, blocking it completely.

Speaking of cylinder valves, today they have only historical value, so they are unable to provide a proper sealing system.Sealing plug valve is provided close fit surfaces of the cone and the valve body.However, they are not able to achieve a perfect sealing because of the impossibility of obtaining two coincident tapered surfaces.To somehow increase the tightness of used grease.In the recent past, with a conical plug valves used widely in water supply, oil and gas pipelines.Currently, these mechanisms become obsolete and your are found only in the samovar and other similar subjects.

In place of these devices come to ball valves, which are able to provide almost 100% tightness even at a sufficiently high pressure in the pipeline, not only for the liquid medium, but also for gas.

ball valves consist of the following components:

• Housing with flanges on inlet and outlet.
• ball with a hole.
• Rings saddles.
• guides.

The flow of water is carried out in either direction without any restrictions.For this reason, the installation of ball valves in the pipeline at any possible position.To open or close a valve, it is sufficient to turn the knob 90 degrees to the initial position.In case there are special stops that limit handle turn at a greater angle.Typically, when a tap is open, it is directed along the handle pipe conduit, and when valve is closed crosswise.Most responsible manufacturers guarantee the normal operation of the ball valve for 4000 cycles.However, this is highly dependent on how aggressive is the environment in which it is necessary to operate the device.

can list other advantages of ball valves:

• Crane with ball mechanism has the same flow coefficient of resistance, as well as the inner surface of the pipe itself, that is close to 1. The rate for the valve in 4 - 5 times higher, and forconical and cylindrical balls in 3 - 4 times.Practically it is advantageous in power consumption of compressor units, and maintains a constant capacity at a low pressure in the system.Globular
• device has a greater ease of use, since the handle is not required to rotate several times, like a valve, but it is sufficient only to rotate it 90 degrees.
• ideal shutter tightness allows saving water, gas or oil products due to the absence of leaks.
• phenomenal longevity of the device, which is provided by the fact that the wear sleeves of PTFE, as well as brass balls chrome-nickel plated, polished diamond grit, does not take place earlier than 4000 cycles.
• crane stability to high temperatures (up to 120 degrees) enables its use even at very high coolant temperatures.Rubber seals valves are deteriorating even when reaching 70 degrees, and the plug valve begins to flow at 80 degrees.

site At undoubted advantages of ball valves can still be found today valves installed at pipelines often enough.Those and other devices needed and can be advantageously installed at home piping systems.