A volume dynamic balancing system and control method of a free forging hydraulic press

Abstract

The application is suitable for the technical field of hydraulic machines, and provides a volume dynamic balancing system and a control method of a free forging hydraulic machine.The volume dynamic balancing system comprises: an upper liquid filling tank installed on the top of a free forging press main machine; a lower power tank installed on a ground foundation; the free forging press main machine installed on a load-bearing foundation in a pit; an oil supplement pump group installed on the ground foundation; a main cylinder pressure relief valve group installed on the top of the free forging press main machine; and a side cylinder pressure relief valve group installed on the top of the free forging press main machine.The application has the advantages of wide application range, low total equipment height, high stability, high safety, simple device structure and strong anti-pollution ability.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic press technology, and particularly relates to a volume dynamic balancing system and control method for a free forging hydraulic press. Background Technology

[0002] Free forging is a basic process for metal plastic processing. With the increasingly widespread application of free forging hydraulic presses, more and more free forging hydraulic presses are being installed at user sites. Newly built workshops have fewer restrictions on the installation conditions of free forging hydraulic presses, but for upgrading and renovation projects, the overall height of the workshop is low, which limits the height of the free forging hydraulic press.

[0003] To address the height limitations of free forging hydraulic presses, two common methods are employed: 1. Using a pull-down free forging hydraulic press, requiring the excavation of a pit within the workshop for equipment placement. These pits often reach depths of several meters or even deeper, resulting in high construction costs, limited maintenance space, and poor maintainability. 2. Using a pressurized filling method, eliminating the upper filling oil tank but requiring an additional pressurized filling tank. This tank requires daily inspection and has a limited lifespan. Pressurized filling poses significant potential safety risks in the free forging environment. If an oil leak occurs, it takes 3-5 minutes to release the pressure, leading not only to large-scale hydraulic oil leakage and splashing but also a high risk of fire. Therefore, we propose a volumetric dynamic balancing system and control method for free forging hydraulic presses. Summary of the Invention

[0004] The purpose of this invention is to provide a volume dynamic balancing system and control method for a free forging hydraulic press, aiming to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A volumetric dynamic balancing system for a free forging hydraulic press includes:

[0007] The top-filled hydraulic oil tank is installed on top of the main unit of the free forging press;

[0008] The lower power oil tank is installed on the ground foundation and is connected to the upper filling oil tank.

[0009] The main body of the free forging press is installed on a load-bearing foundation in a pit. The main body of the free forging press includes a main cylinder and side cylinders.

[0010] A replenishing pump set is installed on a ground foundation. The replenishing pump set is connected to an upper filling oil tank and a lower power oil tank. The replenishing pump set includes a replenishing pump.

[0011] The main cylinder pressure relief valve assembly is installed on the top of the main body of the free forging press, and the main cylinder pressure relief valve assembly is connected to the upper filling oil tank and the main cylinder;

[0012] The side cylinder pressure relief valve assembly is installed on the top of the main body of the free forging press, and the side cylinder pressure relief valve assembly is connected to the upper filling oil tank and the side cylinder.

[0013] Furthermore, the upper filling oil tank includes:

[0014] Fuel tank casing 1;

[0015] Liquid level sensor 1, two liquid level sensors 1 are respectively installed on the side of the oil tank housing 1;

[0016] The bottom of the upper filling oil tank is connected to the bottom of the lower power oil tank via an oil pipe.

[0017] An air connecting pipe is provided, and the top of the upper filling oil tank is connected to the top of the lower power oil tank via the air connecting pipe.

[0018] Pipeline 1 and Pipeline 2 are connected to the main cylinder via Pipeline 1 and the side cylinder via Pipeline 2.

[0019] Furthermore, the lower power oil tank includes:

[0020] Fuel tank shell two;

[0021] Liquid level sensor two is installed on the side of tank housing two;

[0022] Air filters, with two sets of the air filters installed on top of the lower power oil tank;

[0023] A pneumatic proportional control valve is installed at the bottom of the lower power oil tank;

[0024] External connecting pipes are used to connect the lower power oil tank, upper filling oil tank, replenishing pump, master cylinder and side cylinder.

[0025] Furthermore, the main body of the free forging press also includes:

[0026] The slider is connected to both the main cylinder and the side cylinder, and both the main cylinder and the side cylinder are used to drive the slider downward.

[0027] The return cylinder, connected to the slider, is used to drive the slider to return.

[0028] The displacement sensor is provided in two parts. One end of the displacement sensor is fixed on the main body of the free forging press, and the other end of the displacement sensor is connected to the slider. The displacement sensor is used to measure the position of the side cylinder and the main cylinder.

[0029] External connecting pipes are used to connect the upper filling oil tank, the main cylinder, and the side cylinders.

[0030] Furthermore, the replenishment pump assembly also includes:

[0031] The oil replenishment motor is connected to the oil replenishment pump and is used to drive the oil replenishment pump to rotate clockwise. The oil replenishment pump is used to draw oil from the lower power oil tank.

[0032] The oil replenishment solenoid valve is used to control the replenishment of oil to the upward-filling oil tank;

[0033] External connecting pipes are used to connect the lower power oil tank, the upper filling oil tank, and the replenishing pump.

[0034] Furthermore, the master cylinder pressure relief valve assembly includes:

[0035] The main cylinder pressure relief forged valve is connected to the oil tank housing through pipeline three, and the main cylinder pressure relief forged valve is connected to the main cylinder through pipeline four.

[0036] External connecting pipes three and four.

[0037] Furthermore, the side cylinder pressure relief valve assembly includes:

[0038] A side cylinder pressure relief forged valve, wherein the side cylinder pressure relief forged valve is connected to the oil tank housing one through pipeline five, and the side cylinder pressure relief forged valve is connected to the side cylinder through pipeline six;

[0039] External connecting pipes five and six.

[0040] A method for controlling the above-mentioned dynamic volume balance includes the following steps:

[0041] Step 1: Assemble the free forging hydraulic press system;

[0042] Step 2: Start the free forging hydraulic press;

[0043] Step 3: The liquid level sensor detects the liquid level in the upper filling tank and calculates the dynamic volume V1 of the oil in the upper filling tank; the displacement sensor detects the displacement of the side cylinder and the main cylinder and calculates the dynamic volume V2 of the oil in the side cylinder and the main cylinder.

[0044] Step 4: When the sum of V1 and V2 is less than the oil volume of 1.3 times the stroke of the free forging press, control the oil replenishment solenoid valve to work, so that the lower power oil tank replenishes oil to the upper filling oil tank until V1 + V2 is greater than or equal to the oil volume of 1.3 times the stroke of the free forging press.

[0045] Step 5: When the slider moves up and down, the liquid level height of the upper filling oil tank is collected by two liquid level height sensors. After low-pass filtering to eliminate the interference signal of liquid level fluctuation, the dynamic volume V1 of the oil in the upper filling oil tank is calculated. The displacement of the side cylinder and the main cylinder is detected by two displacement sensors, and the dynamic volume V2 of the oil in the side cylinder and the main cylinder is calculated.

[0046] Step 6: Using a PID control algorithm with dead zone, control the pneumatic proportional regulating valve to discharge oil from the upper filling oil tank to the lower power oil tank, keeping the sum of the dynamic volumes of oil in V1 and V2 at 1.3 times the free forging press stroke, thus achieving balanced control of the dynamic volume of oil in the upper filling oil tank.

[0047] Step 7: The free forging hydraulic press continuously repeats steps 5 and 6 during its operation.

[0048] Compared with the prior art, the beneficial effects of the present invention are:

[0049] (1) Wide range of applications: It is not only applicable to free forging presses, but also to equipment with liquid filling tanks and limited installation height, such as high-speed forging presses.

[0050] (2) Overall equipment height: Conventional atmospheric pressure filling oil tanks require 2-3 strokes of oil volume to be reserved, and 1 stroke space to be reserved at the top; the volume dynamic balance system proposed in this invention only requires 1.3 strokes of oil volume and 0.5 stroke safety margin, which reduces the oil tank height by 55% compared to the atmospheric pressure system, and reduces the oil filling amount of the upper filling oil tank by 56%.

[0051] (3) High stability: Two redundant liquid level sensors are installed at the upper filling oil tank to detect and compare each other, and a filtering algorithm is used to eliminate liquid level fluctuation interference, ensuring the reliability and accuracy of the upper filling oil tank volume calculation.

[0052] (4) High safety: The oil in the atmospheric pressure filling system is not pressurized when the cylinder is filled, and the risk of pipeline leakage is small, making it more suitable for free forging.

[0053] (5) The device has a simple structure: it only requires the addition of oil pipes, air connecting pipes, pneumatic proportional regulating valves and oil replenishment pumps to the original atmospheric pressure filling system. The changes are relatively small compared to the atmospheric pressure system, and the initial investment is small.

[0054] (6) Strong anti-pollution capability: Compared with the atmospheric pressure filling system, the upper filling oil tank of the volume dynamic balance system has no filter. The upper filling oil tank and the lower power oil tank are connected by an air connecting pipe, which avoids the contaminants at the work site from entering the oil tank through the air filter of the upper filling oil tank and causing oil contamination. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the structure of the present invention.

[0056] In the diagram: Upper filling oil tank 1, oil tank shell 1.1, liquid level sensor 1.2, oil pipe 1.3, air connecting pipe 1.4, pipeline 1.5, pipeline 2.6, Lower power oil tank 2, oil tank shell 2.1, liquid level sensor 2.2, air filter 2.3, pneumatic proportional regulating valve 2.4, free forging press main unit 3, slider 3.1, side cylinder 3.2, main cylinder 3.3, return cylinder 3.4, displacement sensor 3.5, replenishing oil pump group 4, replenishing oil motor 4.1, replenishing oil pump 4.2, replenishing oil solenoid valve 4.3, main cylinder pressure relief valve group 5, main cylinder pressure relief forging valve 5.1, pipeline 3 5.2, pipeline 4 5.3, side cylinder pressure relief valve group 6, side cylinder pressure relief forging valve 6.1, pipeline 5 6.2, pipeline 6 6.3. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0058] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0059] like Figure 1 As shown, a volumetric dynamic balancing system for a free forging hydraulic press, according to an embodiment of the present invention, includes:

[0060] The upper filling oil tank 1 is installed on top of the main body 3 of the free forging press;

[0061] The lower power oil tank 2 is installed on the ground foundation and is connected to the upper filling oil tank 1.

[0062] The main body 3 of the free forging press is installed on a load-bearing foundation in the pit. The main body 3 of the free forging press includes a main cylinder 3.3 and a side cylinder 3.2.

[0063] The replenishing pump assembly 4 is installed on the ground foundation. The replenishing pump assembly 4 is connected to the upper filling oil tank 1 and the lower power oil tank 2. The replenishing pump assembly 4 includes a replenishing pump 4.2.

[0064] The main cylinder pressure relief valve assembly 5 is installed on the top of the main body 3 of the free forging press. The main cylinder pressure relief valve assembly 5 is connected to the upper filling oil tank 1 and the main cylinder 3.3.

[0065] The side cylinder pressure relief valve assembly 6 is installed on the top of the main body 3 of the free forging press. The side cylinder pressure relief valve assembly 6 is connected to the upper filling oil tank 1 and the side cylinder 3.2.

[0066] like Figure 1 As shown, in a preferred embodiment of the present invention, the upper-filling oil tank 1 includes:

[0067] Fuel tank casing - 1.1;

[0068] Liquid level sensor 1.2, two liquid level sensors 1.2 are respectively installed on the side of the oil tank housing 1.1;

[0069] Oil pipe 1.3 connects the bottom of the upper filling oil tank 1 to the bottom of the lower power oil tank 2 via oil pipe 1.3.

[0070] Air connecting pipe 1.4, the top of the upper filling oil tank 1 is connected to the top of the lower power oil tank 2 through the air connecting pipe 1.4;

[0071] Pipeline 1.5 and pipeline 2.6 are connected to the main cylinder 3.3 via pipeline 1.5 and the side cylinder 3.2 via pipeline 2.6.

[0072] In this embodiment of the invention, preferably, the liquid level height of the upper filling oil tank 1 is detected by two liquid level height sensors 1.2. Since the bottom area of ​​the upper filling oil tank 1 is fixed, the dynamic volume V1 of the oil in the upper filling oil tank 1 can be calculated.

[0073] like Figure 1 As shown, in a preferred embodiment of the present invention, the lower power oil tank 2 includes:

[0074] Fuel tank casing 2.1;

[0075] Liquid level sensor 2.2 is installed on the side of tank housing 2.1;

[0076] Air filters 2.3, two sets of air filters 2.3 are installed on top of the lower power oil tank 2;

[0077] The pneumatic proportional regulating valve 2.4 is installed at the bottom of the lower power oil tank 2;

[0078] External connecting pipes are used to connect the lower power oil tank 2, the upper filling oil tank 1, the replenishing pump 4.2, the master cylinder 3.3, and the side cylinder 3.2.

[0079] In a preferred embodiment of the invention, when the slider 3.1 moves up and down, an external 4-20mA analog electrical signal is used to control the pneumatic proportional regulating valve 2.4 to discharge oil from the downward power oil tank 2.

[0080] like Figure 1 As shown, in a preferred embodiment of the present invention, the free forging press main unit 3 further includes:

[0081] The slider 3.1 is connected to both the main cylinder 3.3 and the side cylinder 3.2. Both the main cylinder 3.3 and the side cylinder 3.2 are used to drive the slider 3.1 downward.

[0082] Return cylinder 3.4 is connected to slider 3.1 and is used to drive slider 3.1 to return;

[0083] Displacement sensor 3.5, two displacement sensors 3.5 are provided. One end of the displacement sensor 3.5 is fixed on the main body 3 of the free forging press, and the other end of the displacement sensor 3.5 is connected to the slider 3.1. The displacement sensor 3.5 is used to measure the position of the side cylinder 3.2 and the main cylinder 3.3.

[0084] External connecting pipes are used to connect the upper filling oil tank 1, the main cylinder 3.3 and the side cylinder 3.2.

[0085] In a preferred embodiment of the invention, when the side cylinder 3.2 and the main cylinder 3.3 drive the slider 3.1 downwards, the free forging press main unit 3 draws oil from the upper filling oil tank 1 through pipeline 1.5 and pipeline 1.6. The displacement of the side cylinder 3.2 and the main cylinder 3.3 is detected by two displacement sensors 3.5. Since the areas of the side cylinder 3.2 and the main cylinder 3.3 are fixed, the dynamic volume V2 of the oil in the side cylinder 3.2 and the main cylinder 3.3 can be calculated.

[0086] like Figure 1 As shown, in a preferred embodiment of the present invention, the replenishing pump assembly 4 further includes:

[0087] The oil replenishing motor 4.1 is connected to the oil replenishing pump 4.2 and is used to drive the oil replenishing pump 4.2 to rotate clockwise. The oil replenishing pump 4.2 is used to draw oil from the lower power oil tank 2.

[0088] The oil replenishment solenoid valve 4.3 is used to control the replenishment of oil to the upward filling oil tank 1;

[0089] External connecting pipes are used to connect the lower power oil tank 2, the upper filling oil tank 1, and the replenishing oil pump 4.2.

[0090] In a preferred embodiment of the invention, when the slider 3.1 moves up and down, the oil replenishing solenoid valve 4.3 is controlled to replenish the oil tank 1 by controlling an external digital electrical signal.

[0091] like Figure 1 As shown, in a preferred embodiment of the present invention, the master cylinder pressure relief valve assembly 5 includes:

[0092] The main cylinder pressure relief forged valve 5.1 is connected to the oil tank housing 1.1 via pipeline 3 5.2 and to the main cylinder 3.3 via pipeline 4 5.3.

[0093] External connecting pipes 3.5.2 and 4.5.3.

[0094] like Figure 1As shown, in a preferred embodiment of the present invention, the side cylinder pressure relief valve assembly 6 includes:

[0095] A side cylinder pressure relief forged valve 6.1 is connected to the oil tank housing 1.1 via pipeline 6.2, and to the side cylinder 3.2 via pipeline 6.3.

[0096] External connecting pipes 5.6.2 and 6.3.

[0097] In a preferred embodiment of the invention, when the slider 3.1 of the free forging press 3 is driven back by the return cylinder 3.4, oil is discharged upward into the liquid oil tank 1 through pipeline 3 5.2, pipeline 4 5.3, pipeline 5 6.2 and pipeline 6 6.3.

[0098] When the side cylinder 3.2 and the main cylinder 3.3 drive the slide block 3.1 downwards, the main body 3 of the free forging press draws oil from the upper filling oil tank 1 through pipe 1.5 and pipe 1.6. When the slide block 3.1 of the main body 3 of the free forging press returns to its original position driven by the return cylinder 3.4, it discharges oil to the upper filling oil tank 1 through pipe 5.2, pipe 5.3, pipe 6.2, and pipe 6.3. During operation, the free forging hydraulic press continuously repeats the above process, with the slide block 3.1 moving up and down to draw oil from or discharge oil from the upper filling oil tank 1. Simultaneously, two liquid level sensors, 1.2 and 1.2, detect the liquid level in the upper filling oil tank 1. Since the bottom area of ​​the upper filling oil tank 1 is fixed, the dynamic volume V1 of the oil in the upper filling oil tank 1 is calculated. Displacement sensor 3.5 detects the displacement of the side cylinder 3.2 and the main cylinder 3.3. Since the areas of the side cylinder 3.2 and the main cylinder 3.3 are fixed, the dynamic volume V2 of the oil in the side cylinder 3.2 and the main cylinder 3.3 is calculated. When the slider 3.1 moves up and down, an external 4-20mA analog electrical signal controls the pneumatic proportional regulating valve 2.4 to discharge oil into the lower power oil tank 2; or an external digital electrical signal controls the oil replenishment solenoid valve 4.3 to replenish oil into the upper filling oil tank 1, thus keeping the sum of the dynamic volume V1 of the oil in the upper filling oil tank 2 and the dynamic volume V2 of the oil in the side cylinder 3.2 and the main cylinder 3.3 constant.

[0099] An embodiment of the present invention provides a method for controlling the dynamic volume balance, comprising the following steps:

[0100] Step 1: Assemble the free forging hydraulic press system;

[0101] Step 2: Start the free forging hydraulic press;

[0102] Step 3: The liquid level sensor 1.2 detects the liquid level of the upper filling oil tank 1 and calculates the dynamic volume V1 of the oil in the upper filling oil tank 1; the displacement sensor 3.5 detects the displacement of the side cylinder 3.2 and the main cylinder 3.3 and calculates the dynamic volume V2 of the oil in the side cylinder 3.2 and the main cylinder 3.3.

[0103] Step 4: When the sum of V1 and V2 is less than the oil volume of 1.3 times the stroke of the free forging press, control the oil replenishment solenoid valve 4.3 to work, so that the lower power oil tank 2 replenishes oil to the upper filling oil tank 1 until V1 + V2 is greater than or equal to the oil volume of 1.3 times the stroke of the free forging press.

[0104] Step 5: When the slider 3.1 moves up and down, the liquid level height of the upper filling oil tank 1 is collected by two liquid level height sensors 1.2. After low-pass filtering to eliminate the interference signal of liquid level fluctuation, the dynamic volume V1 of the oil in the upper filling oil tank 1 is calculated. The displacement of the side cylinder 3.2 and the main cylinder 3.3 is detected by two displacement sensors 3.5, and the dynamic volume V2 of the oil in the side cylinder 3.2 and the main cylinder 3.3 is calculated.

[0105] Step 6: Using a PID control algorithm with dead zone, control the pneumatic proportional regulating valve 2.4 to discharge oil from the upper filling oil tank 1 to the lower power oil tank 2, keeping the sum of the dynamic volumes of oil in V1 and V2 at 1.3 times the free forging press stroke, thus achieving balanced control of the dynamic volume of oil in the upper filling oil tank 1.

[0106] Step 7: The free forging hydraulic press continuously repeats steps 5 and 6 during its operation.

[0107] Step 8: When the free forging hydraulic press stops or malfunctions, the pneumatic proportional regulating valve 2.4 is pushed back by the spring and automatically closes the oil discharge.

[0108] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A volume dynamic balancing system for a free forging hydraulic press, characterized by, The utility model relates to a kind of free forging hydraulic press system, including: Upper liquid-filled oil tank, installed on the top of free forging press host machine; Lower power oil tank, installed on ground foundation, the lower power oil tank is connected with upper liquid-filled oil tank; Free forging press host machine, installed on the load-bearing foundation in pit, the free forging press host machine includes main cylinder and side cylinder; Oil supplement pump group, installed on ground foundation, the oil supplement pump group connects upper liquid-filled oil tank and lower power oil tank, and the oil supplement pump group includes oil supplement pump; Main cylinder pressure relief valve group, installed on the top of free forging press host machine, the main cylinder pressure relief valve group connects upper liquid-filled oil tank with main cylinder; Side cylinder pressure relief valve group, installed on the top of free forging press host machine, the side cylinder pressure relief valve group connects upper liquid-filled oil tank with side cylinder; The upper liquid-filled oil tank includes: Oil tank shell one; Liquid level sensor one, two the liquid level sensor one is respectively installed on the side of oil tank shell one; Oil pipe, the bottom of upper liquid-filled oil tank is connected with the bottom of lower power oil tank through oil pipe, Air communication pipe, the top of upper liquid-filled oil tank is connected with the top of lower power oil tank through air communication pipe; Pipe one and pipe two, upper liquid-filled oil tank is connected with main cylinder through pipe one, and upper liquid-filled oil tank is connected with side cylinder through pipe two; The lower power oil tank includes: Oil tank shell two; Liquid level sensor two, installed on the side of oil tank shell two; Air filter, two groups of air filter are installed on the top of lower power oil tank; Pneumatic proportional control valve, installed on the bottom of lower power oil tank; Externally connected pipe, for connecting lower power oil tank, upper liquid-filled oil tank, oil supplement pump, main cylinder and side cylinder; The free forging press host machine further includes: Slide block, the main cylinder and side cylinder are connected with slide block, and the main cylinder and side cylinder are used to drive slide block down; Return cylinder, connected with slide block, for driving slide block back; Displacement sensor, two displacement sensors are provided, one end of the displacement sensor is fixed on free forging press host machine, and the other end of the displacement sensor is connected with slide block, and the displacement sensor is used to measure the position of side cylinder and main cylinder; Externally connected pipe, for connecting upper liquid-filled oil tank, main cylinder and side cylinder; The oil supplement pump group further includes: Oil supplement motor, connected with oil supplement pump, for driving oil supplement pump to rotate clockwise, and the oil supplement pump is used to suck oil from lower power oil tank; Oil supplement solenoid valve, for controlling oil supplement to upper liquid-filled oil tank; Externally connected pipe, for connecting lower power oil tank, upper liquid-filled oil tank and oil supplement pump; The main cylinder pressure relief valve group includes: Main cylinder pressure relief forging valve, the main cylinder pressure relief forging valve is connected with oil tank shell one through pipe three, and the main cylinder pressure relief forging valve is connected with main cylinder through pipe four; Externally connected pipe three and pipe four; The side cylinder pressure relief valve group includes: Side cylinder pressure relief forging valve, the side cylinder pressure relief forging valve is connected with oil tank shell one through pipe five, and the side cylinder pressure relief forging valve is connected with side cylinder through pipe six; Externally connected pipe five and pipe six.

2. A control method for the volume dynamic balancing system of the free forging hydraulic press according to claim 1, characterized in that, Including the following steps: Step 1, complete assembly of free forging hydraulic press system; Step 2, start free forging hydraulic press. Step 3: The liquid level sensor detects the liquid level in the upper filling tank and calculates the dynamic volume V1 of the oil in the upper filling tank; the displacement sensor detects the displacement of the side cylinder and the main cylinder and calculates the dynamic volume V2 of the oil in the side cylinder and the main cylinder. Step 4: When the sum of V1 and V2 is less than the oil volume of 1.3 times the stroke of the free forging press, control the oil replenishment solenoid valve to work, so that the lower power oil tank replenishes oil to the upper filling oil tank until V1 + V2 is greater than or equal to the oil volume of 1.3 times the stroke of the free forging press. Step 5: When the slider moves up and down, the liquid level height of the upper filling oil tank is collected by two liquid level height sensors. After low-pass filtering to eliminate the interference signal of liquid level fluctuation, the dynamic volume V1 of the oil in the upper filling oil tank is calculated. The displacement of the side cylinder and the main cylinder is detected by two displacement sensors, and the dynamic volume V2 of the oil in the side cylinder and the main cylinder is calculated. Step 6: Using a PID control algorithm with dead zone, control the pneumatic proportional regulating valve to discharge oil from the upper filling oil tank to the lower power oil tank, keeping the sum of the dynamic volumes of oil in V1 and V2 at 1.3 times the free forging press stroke, thus achieving balanced control of the dynamic volume of oil in the upper filling oil tank. Step 7: The free forging hydraulic press continuously repeats steps 5 and 6 during its operation.

Images