Three disadvantages of hydraulic system

1.Heating

Because the medium (hydraulic oil) exist different velocity in different parts of the flow process, leading to the existence of the internal friction, there is also a friction between the liquid and the inner wall of the pipeline at the same time, these are the causes of the hydraulic oil temperature rise. The increase of temperature will lead to the increase of internal and external leakage and reduce the mechanical efficiency. At the same time, due to the high temperature, hydraulic oil will expand, resulting in compressibility increase, so that the control action can not be transfered very good.
Solution: heating is an inherent feature of the hydraulic system, can not be eradicated as far as possible to alleviate. The use of good quality hydraulic oil, hydraulic piping layout should try to avoid the elbow, the use of high quality pipes and pipe joints, hydraulic flow valves, etc..

2.Vibration

The vibration of the hydraulic system is one of the chronic illness. Because of the high speed flow of the hydraulic oil in the pipeline and the impact of the hydraulic pressure control valve opening and closing process is the cause of the vibration of the system. Strong vibration will cause the error of the control action of the system, will also cause error of some the more precise instrument of the system, resulting in system failure.
Solution: the hydraulic pipe should be fixed to avoid sharp bends. Avoid change the direction of fluid flow frequently, the vibration mitigation measures should be done when can not be avoided. The entire hydraulic system should have good damping measures, while avoiding the external forces on the system.

3.Leakage

The leakage of hydraulic system is divided into internal leakage and external leakage. Internal leakage refers to the leakage process occurs in the system, such as the leakage of hydraulic cylinder piston on both sides, the leakage between control valve spool and hydraulic directional spool valve. Although the internal leakage will not cause the loss of hydraulic oil, but due to the leakage, the established control action may be affected until the system failure. External leakage is the leakage between the system and the external environment. Hydraulic oil leaking into the environment directly, in addition will affect the working environment of the system, but also lead to system failure caused by insufficient pressure. Leakage of oil into the environment will also gain the risk of fire.
Solution: the use of good quality seals, improve equipment processing accuracy.

BSTIND Z2FS modular throttle check valve

MAX 315 bar, MAX 160 L/min, MAX 35MPa

Sandwich plate valve
Porting pattern to ISO 4401-05-04-0-05, NFPA T3.5.1 R2 and ANSI B93-7 D05
For limiting the main or pilot oil flow of 2 actuator ports
3 adjustment elements:
-Lockable rotary knob with scale
-Spindle with hexagon socket and scale
-Rotary knob with scale
For meter-in and meter-out throttling

Hydraulic components can be divided into power components and control components and executive component

Hydraulic components can be divided into power components and control components and executive component. Although they are all hydraulic components, their own function and installation of the technical requirements are not the same.

Power components: refers to a variety of hydraulic pumps, gear pumps, vane pumps, piston pumps, screw pumps.
1.Gear pump and series pump (including external and internal meshing) structural types.
2.Vane pump (including single stage pump, variable pump, double stage pump, double pump).
3.The plunger pump is divided into axial piston pump and radial piston pump, axial piston pump is divided into variable pump, quantitative pump (variable pump is divided into manual and variable pressure compensating variable, servo variable etc.) . From the structure is divided into the end face type and oil distribution valve type oil distribution mode, and the radial plunger pump with oil type, basically for valve type oil distribution.

Executive component: hydraulic cylinder and hydraulic motor, hydraulic cylinder hydraulic cylinder piston, piston hydraulic cylinder, hydraulic cylinder, hydraulic cylinder combination swing hydraulic motor; gear hydraulic motor is divided into hydraulic vane motor, piston hydraulic motor.

Control components: reversing valve, modular check valve, hydraulics directional control valve.
Pressure control valve: relief valve, pressure relief valve, sequence valve, hydraulic pressure valve, etc.
Flow control valve: throttle valve, speed control valve, shunt valve.

Auxiliary components: in addition to the above three parts components, including pressure gauge, oil filter, accumulator, cooler, fittings {mainly include: various pipe fittings (flared, welding type, sleeve type, SAE flange), high pressure ball valves, quick couplings, hose assembly, pressure measuring joint and the pipe clip} and tank, they are also very important.

4WE3-61 hydraulic solenoid miniature hydraulic valve

Max working oil pressure P.A.B : 31.5 MPa
Max oil pressure for T chamber : 10 MPa
Rated flow : 10 l/min
Max flow : 15 l/min

NG3 valve with 3 holes
4/2-way impulse valve
4/3-way with centered mid position spring
4/2-way with spring reset.
Q max.=15l/min,P max.=315Bar

The advantages of hydraulic system

Compared with mechanical transmission and electric drive, hydraulic transmission has the following advantages:
1.Various components of hydraulic transmission can be layout conveniently and flexibly .
2.Light weight, small size, small inertia, fast reaction speed.
3.Easy operation and control, can achieve a wide range of stepless speed regulation (speed range of 2000:1).
4.Automatic overload protection.
5.Generally use mineral oil as working medium, relative motion surface can be self lubrication, long service life.
6.Easy to achieve linear motion.
7.It is easy to realize the automation of the machine. When using the combined control of the electro-hydraulic, not only can achieve a higher degree of automatic control process, but also can achieve remote control.

BSTIND is a professional manufacturer of hydraulic system valves,high quality and reasonable price,serve for B2B customers,looking forward to get your inquiry.

The hydraulic system is divided into different forms

The hydraulic components and gradually realize the standardization and serialization of the varieties, its specifications, quality and performance have been greatly improved, especially the new technology such as electronic technology, servo technology and so on, the quality of the hydraulic system has been greatly improved, which has played an important role in the national economy and military industry. From different points of view, the hydraulic system can be divided into different forms.

1.According to the circulation of oil, hydraulic system can be divided into open system and closed system. Open system refers to the hydraulic pump drain oil from the tank, the oil through a variety of electric hydraulic control valves, to drive hydraulic components, then return to the tank through the hydraulics directional control valve. The structure of the system is relatively simple, and can play the role of heat dissipation and precipitation of the fuel tank, but because the oil is often in contact with the air, the air is easy to penetrate into the system, resulting in the unstable motion of the mechanism. The oil tank of open system is big, and the oil pump self-priming performance is good. In the closed system, the oil inlet pipe of the hydraulic pump is directly connected with the oil return pipe of the actuating element, the working fluid in the system for closed loop pipeline.Its structure is compact, less contact with air, and air is not easy to penetrate the system, so the transmission is more stable. The speed and direction of the working mechanism are realized by adjusting the variable mechanism of the pump or the motor, so as to avoid the hydraulic shock and energy loss in the process of the opening system. However, the closed system is more complex than the open system, because there is no oil tank, the oil cooling and filtration conditions are poor. In order to compensate for the leakage in the system, a small flow oil pump and oil tank is needed. As the single pole double acting cylinder large cavity flow range, in the work process will make use of power down, so the implementation of a closed system components for hydraulic motor.

2.According to the number of hydraulic pumps in the system, can be divided into single pump system, double pump system and multi pump system.

3.According to the different forms of hydraulic pump, can be divided into quantitative pump system and variable pump system. The advantages of variable pump is that it can make full use of the power of the engine within the scope of the regulation, but its structure and manufacturing process is complex and high cost, which can be divided into manual variables, as far as possible control variables, servo variable, pressure compensating variable and constant pressure variable, hydraulic variable etc..

4.According to the different ways of oil supply, the system can be divided into series system and parallel system. In the series system, the oil return of the last executive element which is the oil inlet of the next executive element, and the pressure of each component is reduced by one time. In the series system, when the main pump supply oil to each of the actuators controlled by the multi way valve, as long as the outlet pressure of the hydraulic pump is sufficient, the movement of the actuating elements can be realized. However, due to the pressure of the components are superimposed, so the external load capacity will be reduced with the increase of the number of components. In parallel systems, when a hydraulic pump supply oil to a set of actuators, the flow into each of the actuators is only part of the output flow of the hydraulic pump. Flow distribution varies with the load of different parts, first into the small load actuator, the simultaneous action can be achieved only when the load of the actuators are equal. The advantages and disadvantages of the mechanical performance of the full hydraulic transmission mainly depends on the performance of the hydraulic system, including the quality of the components, the basic circuit is appropriate or not, etc.. The performance of the system, in addition to meet the functional requirements, should be evalutated in installation and debugging efficiency, power from hydraulic system use, speed range and fine tuning characteristics, vibration and noise and the system is convenient and reliable etc.. Modern engineering machinery almost all use the hydraulic system, and combine with the electronic system and computer control technology, become an important part of modern construction machinery.

Disadvantages of hydraulic system

1.Because of the large resistance and leakage of fluid flow, the efficiency is low. If not handled properly, the leakage not only pollute the site, but also may cause fire and explosion accidents.
2.Because the performance of the work is easy to be affected by the temperature change, it is not suitable to work at high or low temperature.
3.High accuracy of hydraulic components, such as the hydraulic pressure valve, so the price is relatively expensive.
4.Due to the leakage of the liquid medium and the compressibility, it can not get the strict transmission ratio.
5.Hydraulic transmission is not easy to find out the reasons for failure; require a higher level of technology for operation and maintenance.