Where and where to apply hydraulic differential circuits

Hydraulic differential is mainly used in heavy machinery, in the process of actuator (or equipment) movement, can make its running speed relatively fast, under the action of pressure to complete the fast forward process. in the press.

The hydraulic differential connection of related equipment can complete a rapid downward movement.

In practical applications, hydraulic systems.

The commutation of the actuator is to change the oil connection of the single-rod cylinder through the control valve, by changing the spool position of the reversing valve, thereby changing the connection mode of the oil circuit, changing the running direction of the actuator, so that it has a different working mode, and finally obtains the working cycle of fast forward (differential connection) work feed (large cavity oil inlet) fast rewind (small cavity oil inlet). The differential connection realizes the most effective way to complete the fast forward without increasing the flow rate of the hydraulic pump, and it is widely used in the hydraulic power slide of combination machine tools and various special machine tools.

The differential circuit feeds oil from the rodless cavity so that the oil with the rod cavity returns to the rodless cavity. Under the same pressure (what we commonly call pressure), the area difference between the rodless cavity and the rod cavity is used to produce a pressure f difference, which drives the hydraulic cylinder to stretch out. Because the oil with the rod cavity returns to the rodless cavity, the hydraulic cylinder can move at a fast speed to achieve a small flow rate and high speed.

Let's talk about what areas you focus on.

Relief valves.

The main hydraulic components used in the pressure regulating circuit are () aPressure Reducing Valve, BThrottle valve, cRelief valves, the answer is cRelief valves.

The pressure regulating circuit is to keep the pressure of the hydraulic transmission system or a certain branch of the hydraulic transmission system constant or not more than a certain value, so as to meet the requirements of matching the working pressure with the external load and maintaining stability or to prevent the overload of the hydraulic transmission system. There are many types of voltage regulation circuits, which can be divided into first-stage voltage regulation circuits, second-stage voltage regulation circuits and multi-stage voltage regulating circuits.

Pneumatic circuit and hydraulic circuit are widely used in the field of mechanical engineering as a commonly used energy transmission method for annual reform. Although both of them transfer energy through fluids, there are many differences and similarities and differences in the way of implementation, transfer medium, characteristics and application scope.

First of all, the biggest difference between pneumatic and hydraulic circuits is the different transfer medium. The pneumatic circuit transmits energy through the flow of gas formed by compressed air at high pressure, while the hydraulic circuit transmits energy through the flow of liquid formed by compressed liquid under high pressure. Due to their compressibility and expandability, gases are slightly less efficient at transferring energy as compared to liquids.

However, the working pressure of the pneumatic circuit is much smaller than that of the hydraulic circuit, and its noise is also smaller, and it is not easy to be affected by medium pollution, etc., so it has unique advantages in some application fields.

Secondly, in terms of implementation, pneumatic circuits often use pneumatic components and actuators, such as cylinders, air motors, pneumatic valves, etc. These pneumatic components are simple in structure, good sealing, easy to maintain, and slightly more adaptable to unconventional working conditions. The hydraulic circuit generally adopts components such as hydraulic pumps, oil cylinders, hydraulic motors and hydraulic control valves, and the hydraulic components are relatively small in size and compact in structure, but the maintenance of the hydraulic system is difficult, more energy-consuming, and generally affected by the medium, especially in the case of low ambient temperature.

Finally, there are differences between pneumatic and hydraulic circuits in terms of application areas. Due to the simple structure, easy adjustment and small output power of pneumatic components, they are generally used in fields that require rapid movement, such as manipulators, automated production lines, reciprocating conveyors, etc. The output power of the hydraulic system is larger, which is more suitable for mechanical equipment that requires strong force support, such as elevators, excavators, crushers and other large hydraulic machinery and equipment.

To sum up, although both pneumatic circuits and hydraulic circuits transmit energy through fluids, there are great differences between them in terms of transfer medium, implementation mode, characteristics and application range. Therefore, in the actual mechanical engineering project, engineers can comprehensively consider these similarities and differences according to different engineering requirements, and select appropriate circuit types and components to meet the engineering needs of different fields and different requirements. <>

The pressure of the left and right chambers of the differential hydraulic cylinder is equal, but the effective area of the rodless cavity is greater than that of the rod cavity, so the force is large, and the piston moves from the rodless cavity to the rod cavity, and the oil with the rod cavity returns to the rodless cavity during the differential, and the flow rate increases, so the speed becomes faster. For example, the general cylinder extension speed is 4q d2, then the speed when differential is 4q d2, it can be seen that the speed of the differential circuit is fast.

That is, in the stroke of the piston rod of the oil cylinder, the rodless cavity is supplied with oil, and at the same time, the oil supply pipeline of the rod and the rodless two cavities of the oil cylinder is connected with each other, and the oil return of the cylinder piston directly flows into the rodless cavity because of the rodless cavity, so the speed of extension is faster than the conventional extension speed.

The reason why it is possible to operate during differential is that the piston rod will extend because the oil supply pressure of the two chambers is equal (because they are connected) and the rodless cavity area is larger.

Differential circuits are a common method used in hydraulic design where rapid extension is required.

The pressure regulating circuit is a part of the pressure control circuit, and the common circuits are as follows:

1) Voltage limiting circuit;

2) Remotely controlled voltage regulating circuit;

3) Electro-hydraulic proportional relief valve pressure regulating circuit.

Generally, there is a relief valve or a pressure reducing valve involved in the implementation.

In addition, the pressure control circuit consists of the following parts:

1) Voltage regulation circuit;

2) unloading circuit;

3) Decompression circuit;

4) Pressurization circuit;

5) Back pressure circuit.

Analyze the basic work of hydraulic pressure regulation circuit, hydraulic differential circuit, pneumatic reversing circuit and pneumatic speed control circuit.

Good friends in the evening, I will answer the basic work of analyzing the hydraulic pressure regulating circuit, hydraulic differential circuit, pneumatic reversing circuit and pneumatic speed control circuit as follows:1Hydraulic Pressure Regulating CircuitThe hydraulic pressure regulating circuit is used to achieve the control of liquid pressure.

Its basic work is to adjust the opening of the throttle valve or servo valve so that the liquid flow reaches a certain value and the wheel reaches the required pressure. Specifically, the basic workflow of the hydraulic pressure regulating circuit is as follows: the pressure value of the liquid is detected by the sensor installed in the system, and the pressure signal is transmitted to the electronic controller, and the electronic controller then controls the opening of the throttle valve or servo valve according to the set parameters, so as to realize the pressure control of the liquid.

2.Hydraulic differential circuitsHydraulic differential circuits are often used to control the bidirectional movement of actuators such as cylinders or hydraulic motors. Its basic work is to use the valve to realize the one-way flow of oil, so that the two chambers of the cylinder form different pressures, so as to realize the movement control of the cylinder.

Specifically, the basic workflow of the hydraulic differential circuit is to control the one-way flow of the oil through manual or automatic control of the valve switch, so that the two chambers of the cylinder form different pressure differences, so as to realize the two-way movement of the cylinder. 3.

Pneumatic reversing circuits: Pneumatic reversing circuits are often used to control the forward and reverse rotation of actuators such as cylinders. Its basic work is to realize the change of the direction of the air source through the control of the air path through the solenoid valve, so as to realize the forward and reverse rotation of the cylinder. Specifically, the basic workflow of a pneumatic commutation circuit is:

The position of the cylinder is detected by the sensor, and the position signal is transmitted to the electronic control device, which controls the opening and closing of the solenoid valve and changes the direction of the air path, so as to realize the forward and reverse rotation of the cylinder. 4.Pneumatic speed control loops: Pneumatic speed control loops are used to control the movement speed of actuators such as cylinders.

Its basic work is to control the flow of the air source by adjusting the opening of the throttle valve or cross-control valve, so as to realize the speed control of the cylinder. Specifically, the basic workflow of the pneumatic speed control loop is as follows: the position or speed of the cylinder is detected by the sensor installed in the system, and the position or speed signal is transmitted to the electronic control device, and the electronic control device controls the opening of the cross-control valve or throttle valve, so as to control the flow of the air source and realize the speed control of the cylinder.

Hydraulic and pneumatic transmission, when designing the circuit, it is necessary to pay attention to the continuity of work.

Hydraulic and pneumatic transmission are common energy transmission methods, and they play an important role in the industrial and mechanical fields. In the design of the circuit, in order to ensure the continuity of work, it is necessary to pay attention to the following points: first, in the efficiency of the clearance transmission and practical application, select the corresponding transmission medium to adapt to the required working conditions, and it is not easy to have work interruption and fluid impact to destroy the phenomenon.

Secondly, it is necessary to reasonably select the volume size of the hydraulic cylinder and the pneumatic cylinder in order to ensure the stability and continuity of the work. In addition, it is also necessary to consider the strength, wear resistance and sealing of the transmission components to prevent oil leakage and air leakage. The knowledge points that need to be paid attention to in the design circuit of hydraulic and pneumatic transmission cover the fields of mechanical transmission, mechanics, material mechanics and fluid mechanics.

In specific applications, these knowledge points need to be selected and applied according to different working conditions to achieve the best working effect and work continuity. At the same time, hydraulic and pneumatic transmissions are becoming more and more widely used in the industry, and it is increasingly important for engineers and technicians to have an in-depth grasp of these knowledge points.

Hydraulic transmission system. What is used as a pressure regulator for a hydraulic circuit.

There are two ways to realize the flow control return system in the hydraulic transmission system: throttle valve and speed control valve. The flow control valve is a correcting hydraulic control valve that adjusts the flow rate of the valve port by changing the flow area of the valve port, thereby controlling the movement speed of the actuator. There are two kinds of flow valves commonly used by Shanshicheng: throttle valve and speed regulating valve.