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corresponding number with the system
With mechanical transmission, electrical transmission compared to the hydraulic drive has
the following advantages:
1, a variety of hydraulic components, can easily and flexibly to layout.
2, light weight, small size, small inertia, fast response.
3, to facilitate manipulation of control, enabling a wide range of stepless speed regulation
(speed range of 2000:1).
4, to achieve overload protection automatically.
5, the general use of mineral oil as a working medium, the relative motion can be
self-lubricating surface, long service life;
6, it is easy to achieve linear motion
7, it is easy to achieve the automation of machines, when the joint control of the use of
electro-hydraulic, not only can achieve a higher degree of process automation, and remote
control can be achieved.
The shortcomings of the hydraulic system:
1, as a result of the resistance to fluid flow and leakage of the larger, so less efficient. If not
handled properly, leakage is not only contaminated sites, but also may cause fire and
explosion.
2, vulnerable performance as a result of the impact of temperature change, it would be
inappropriate in the high or low temperature conditions. 3, the manufacture of precision hydraulic components require a higher, more expensive and
hence the price.
4, due to the leakage of liquid medium and the compressibility and can not be strictly the
transmission ratio.
5, hydraulic transmission is not easy to find out the reasons for failure; the use and
maintenance requirements for a higher level of technology.
In the hydraulic system and its system, the sealing device to prevent leakage of the work of
media within and outside the dust and the intrusion of foreign bodies. Seals played the role of
components, namely seals. Medium will result in leakage of waste, pollution and environmental
machinery and even give rise to malfunctioning machinery and equipment for personal accident.
Leakage within the hydraulic system will cause a sharp drop in volumetric efficiency,
amounting to less than the required pressure, can not even work. Micro-invasive system of dust
particles, can cause or exacerbate friction hydraulic component wear, and further lead to
leakage.
Therefore, seals and sealing device is an important hydraulic equipment components. The
reliability of its work and life, is a measure of the hydraulic system an important indicator of
good or bad. In addition to the closed space, are the use of seals, so that two adjacent coupling
surface of the gap between the need to control the liquid can be sealed following the smallest
gap. In the contact seal, pressed into self-seal-style and self-styled self-tight seal (ie, sealed lips)
two.
The three hydraulic system diseases
1, as a result of heat transmission medium (hydraulic oil) in the flow velocity in various parts of
the existence of different, resulting in the existence of a liquid within the internal friction of
liquids and pipelines at the sam- e time there is friction between the inner wall, which are a
result of hydraulic the reasons for the oil tempera- ture. Temperature will lead to increased
internal and external leakage, reducing its mechanical efficiency. At the same time as a result of
high temperature, hydraulic oil expansion will occur, resulting in increased com- pression, so
that action can not be very good control of transmission. Solution: heat is the inherent characte