Advantages and disadvantages of valves
Valves are an integral part of the complete set of any pipeline. Their purpose is to completely or partially block the highway. Products of this type have a fairly simple design: the gate element is immersed by means of an axis at an angle of 90 degrees into the medium transported through the pipe.
There is a handle or drive at the top of the axle. The valve is held under pressure due to the thread on the stem and housing.
Classification
According to the type of construction , the valves are divided into 4 groups:
- Passageways. They are equipped with straight sections of the highway. In this respect, they are similar to shut-off flow valves.
- Angular. They are used in combination with an angular fitting.
- Straight-through. Very practical and reliable models, capable of not creating significant resistance to the movement of matter in straight sections.
- Mixing. Provide connection of several threads into one common one. Mixing in the right proportions is carried out inside the housing.
Advantages and disadvantages of valves
An important characteristic of the valves is the degree of tightness in the closed position. In order to avoid even small gaps in high-pressure conditions, many models use oil seals and seals. Achieving tightness is difficult when adjusting very viscous or polluted media.
Advantages of valves in comparison with other shut-off valves:
- simple design and compactness;
- the possibility of installation directly at the place of operation in the field, in hard-to-reach areas and corner branches;
- wide range of operating pressures;
- ability to maintain tightness in unstable pressure mode;
- long service life, with low wear of individual parts;
- the ability to control the intensity of the flow.
The disadvantages of valves include the fact that in the open position the medium forms hydraulic resistance and turbulence. In addition, fittings of this type are very sensitive to impurities. In most modern models, these flaws are practically non-existent leveled.