Water inlet hydraulic system with stable effective volume of oil supplementing tank

Abstract

The utility model relates to a water inlet hydraulic system with a stable effective volume of an oil supplementing tank. The method is suitable for the technical field of water conservancy and hydropower engineering. The technical problem to be solved by the utility model is to provide the water inlet hydraulic system with stable effective volume of an oil supplementing tank. According to the technical scheme, the water inlet hydraulic system with the stable effective volume of the oil supplementing tank is characterized by comprising a hydraulic cylinder used for driving a gate to be opened or closed; the bottom of the oil supplementing tank is communicated with a rodless cavity of the hydraulic cylinder through an oil supplementing pipe, the side face of the oil supplementing tank is communicated with the oil tank through an oil return pipe, the height from the installation center of the oil return pipe in the oil supplementing tank to a bottom plate of the oil supplementing tank is H, H is larger than h, and h is the liquid level height in the oil supplementing tank corresponding to the volume difference of the rodless cavity and the rod cavity of the hydraulic cylinder; the air inlet and exhaust pipeline is provided with an automatic air inlet and exhaust valve which can be controlled to be opened and closed based on the liquid level change in the oil supplementing tank.

Description

Technical Field

[0001] The utility model relates to a water inlet hydraulic system with a stable effective volume of an oil replenishment tank, which is suitable for water conservancy and hydropower projects. Background Art

[0002] The rapid gates at the water inlet of the units of water conservancy and hydropower projects are generally operated by hydraulic hoists. Their function is to close the orifice by the deadweight of the gate and the weight of the water column within a specified time when an accident occurs in the unit, water pump or flow channel to prevent the accident from expanding. The closed gate circuit is designed according to the condition that the AC power supply of the whole plant is lost and the hydraulic pump unit cannot be started. Therefore, the hydraulic system adopts a differential circuit when closing the gate. If the oil inlet of the rodless cavity of the hydraulic cylinder is higher than the pump station, a supplementary oil tank must be set above the oil inlet of the rodless cavity to supplement the oil of the difference in volume between the rodless cavity and the rod cavity of the hydraulic cylinder.

[0003] Since the working pressure of the air filter with breathing function on the oil tank is not large, between 0.02MPa and 0.07MPa, the oil replenishment tank is usually designed as a non-pressure oil tank. When the gate is closed, the oil in the rod chamber of the hydraulic cylinder flows back to the rodless chamber, and the oil replenishment tank automatically replenishes oil to the rodless chamber. When the gate is opened, the oil in the rodless chamber first returns to the oil replenishment tank until the position where the volume difference between the two chambers is met, the control port of the hydraulic control check valve between the rodless chamber and the oil replenishment tank is closed, and the remaining oil in the rodless chamber returns to the main oil tank. The oil replenishment tank is connected to the return oil pipeline through the hydraulic control check valve and the rodless chamber. Due to the internal leakage of the overflow valve on the return oil pipeline, the oil in the oil replenishment tank will leak back to the main oil tank. If the gate is in the fully open position for a long time, the oil volume of the oil replenishment tank may not meet the working needs. If the hydraulic cylinder and the make-up oil tank are arranged above the dam top, the oil will expand due to heat during the day and return to the main oil tank through the overflow valve on the return oil line. At night, the oil will shrink and the oil in the make-up oil tank will be replenished to the rodless chamber. Therefore, the oil in the make-up oil tank cannot meet the need for oil replenishment when the door is closed. Utility Model Content

[0004] The technical problem to be solved by the utility model is: in view of the above existing problems, a water inlet hydraulic system with a stable effective volume of an oil replenishment tank is provided.

[0005] The technical solution adopted by the utility model is: a water inlet hydraulic system with a stable effective volume of the oil replenishment tank, characterized in that it includes:

[0006] Hydraulic cylinder, used to drive the gate to open or close;

[0007] An oil replenishing tank, the bottom of which is connected to the rodless chamber of the hydraulic cylinder via an oil replenishing pipe, and the side of the oil replenishing tank is connected to the oil tank via an oil return pipe, and the height from the installation center of the oil return pipe in the oil replenishing tank to the bottom plate of the oil replenishing tank is H, H is greater than h, and h is the height of the liquid level in the oil replenishing tank corresponding to the volume difference between the rodless chamber and the rod chamber of the hydraulic cylinder;

[0008] The inlet and exhaust pipeline is equipped with an automatic inlet and exhaust valve which can be controlled to open and close based on the change of the liquid level in the oil replenishing tank.

[0009] The intake and exhaust pipelines include an intake and exhaust main route, an intake pipe and an outlet pipe, both of which are connected to the oil replenishing tank via an intake and exhaust main pipe, wherein an air filter and a one-way valve are installed on the intake pipe, the automatic intake and exhaust valve is installed on the intake and exhaust main pipe, and the outlet pipe is connected to a one-way valve.

[0010] An overflow pipe is mounted on the oil replenishing tank, and an overflow valve a is mounted on the overflow pipe.

[0011] The oil return pipe is connected to the control valve group, which is connected to the oil tank via the oil supply pipe and the oil discharge pipe. The oil discharge pipe is connected to the overflow valve b, and the control valve group is connected to the rod chamber of the hydraulic cylinder via the pressure oil pipe.

[0012] The H is greater than the sum of h and the height in the oil replenishing tank corresponding to the expansion volume of the oil.

[0013] The beneficial effects of the utility model are as follows: in the utility model, the oil tank and the rodless chamber of the hydraulic cylinder are connected through the return oil pipe, the replenishing oil tank and the replenishing oil pipe. When the door is closed, the oil in the rod chamber returns to the rodless chamber through the replenishing oil tank. When the door is opened, the oil in the rodless chamber returns to the oil tank through the replenishing oil tank. In addition, in the utility model, the height from the installation center of the return oil pipe in the replenishing oil tank to the bottom plate of the replenishing oil tank is H, and H is greater than the liquid level height h in the replenishing oil tank corresponding to the volume difference between the rodless chamber and the rod chamber of the hydraulic cylinder, ensuring that the oil volume in the replenishing oil tank meets the door closing requirements under any circumstances, thereby solving the problem of unstable effective volume of the replenishing oil tank.

[0014] The utility model arranges an automatic inlet and outlet valve on the oil replenishment tank which can control the opening and closing of the automatic inlet and outlet valve based on the change of the liquid level in the oil replenishment tank, designs the oil replenishment tank into a pressurized closed oil tank, cooperates with the return oil pipe, the oil replenishment pipe, etc., to ensure the stability of the effective volume of the oil replenishment tank under any circumstances. The hydraulic system principle and electrical control of this scheme are simple and reliable, improve the technical performance of the water inlet hydraulic system, and ensure the safety of the water inlet rapid gate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the hydraulic system of an embodiment.

[0016] 1. Hydraulic cylinder; 2. Rodless chamber; 3. Rod chamber; 4. Oil replenishing tank; 5. Check valve; 6. Air filter; 7. Automatic inlet and exhaust valves; 8. Overflow valve a; 9. Oil return pipe; 10. Control valve group; 11. Pressure oil pipe; 12. Overflow valve b; 13. Oil tank. DETAILED DESCRIPTION

[0017] The present embodiment is a water inlet hydraulic system with a stable effective volume of an oil replenishing tank, comprising a hydraulic cylinder, an oil replenishing tank, a control valve group, etc., wherein the hydraulic cylinder is connected to a gate to drive the gate to open or close.

[0018] In this example, the bottom of the oil replenishment tank is connected to the rodless chamber of the hydraulic cylinder via an oil replenishment pipe, and the side of the oil replenishment tank is connected to the oil tank via an oil return pipe, a control valve group, etc.

[0019] To ensure that the oil volume difference between the two chambers is maintained in the oil replenishment tank, the height H from the installation center of the return pipe in the oil replenishment tank to the bottom plate of the oil replenishment tank should be higher than the liquid level height h in the oil replenishment tank corresponding to the volume difference between the rodless chamber and the rod chamber. If the hydraulic cylinder and the oil replenishment tank are arranged above the dam top, the oil volume expansion calculation should be performed, and the installation center height H of the return pipe in the oil replenishment tank should be higher than the sum of the height h of the volume difference between the rodless chamber and the rod chamber and the height of the oil expansion volume in the oil replenishment tank.

[0020] In this embodiment, an inlet and exhaust pipeline and an overflow pipe connected to the inside of the oil filling tank are connected to the top of the oil filling tank, wherein the inlet and exhaust pipeline has an inlet and exhaust main path, an inlet pipe and an outlet pipe, and both the inlet pipe and the outlet pipe are connected to the oil filling tank via an inlet and exhaust main pipe, wherein an air filter and a one-way valve are installed on the inlet pipe, an automatic inlet and exhaust valve that can be controlled to open and close based on the change of the liquid level in the oil filling tank is installed on the inlet and exhaust main pipe, and a one-way valve is connected to the outlet pipe; an overflow valve a is connected to the overflow pipe, and the opening pressure of the overflow valve a is 1.0MPa.

[0021] In this embodiment, the control valve group is connected to the rod chamber of the hydraulic cylinder through a pressure oil pipe. The control valve group is connected to the oil tank through an oil supply pipe and an oil discharge pipe. A pump group is installed on the oil supply pipe, and an overflow valve b is connected to the oil discharge pipe. The opening pressure of the overflow valve b is 0.5MPa.

[0022] In this embodiment, the oil filling tank structure is designed according to the pressure set by the overflow valve a. The one-way valve prevents the air filter from bearing the pressure in the oil filling tank. When the liquid level in the oil filling tank decreases, the float of the automatic inlet and exhaust valve drops into the float cover, and the exhaust valve opens. The air enters the oil filling tank after being filtered by the air filter. When the liquid level in the oil filling tank rises, the oil filling tank exhausts air to the outside through the automatic inlet and exhaust valve.

[0023] When the gate is closed, the oil in the rod chamber of the hydraulic cylinder passes through the pressure oil pipe, the control valve group, and then returns to the rodless chamber through the return oil pipe, the oil replenishing tank, and the oil replenishing pipe. At the same time, part of the oil at height h in the oil replenishing tank is replenished into the rodless chamber. At this time, the air is replenished into the oil replenishing tank through the air filter, the one-way valve and the automatic inlet and exhaust valve.

[0024] When the gate is opened, the pressure oil coming out of the oil tank and the pump group enters the rod chamber through the pressure oil pipe after being changed by the control valve group. The oil in the rodless chamber flows back to the main oil tank through the oil replenishing pipe, the oil replenishing tank and the oil return pipe through the control valve group and the relief valve b. At this time, the automatic air inlet and exhaust valves exhaust to the outside.

Claims

1. A water inlet hydraulic system with a stable effective volume of a replenishing tank, characterized in that: include: Hydraulic cylinder, used to drive the gate to open or close; An oil replenishing tank, the bottom of which is connected to the rodless chamber of the hydraulic cylinder via an oil replenishing pipe, and the side of the oil replenishing tank is connected to the oil tank via an oil return pipe, and the height from the installation center of the oil return pipe in the oil replenishing tank to the bottom plate of the oil replenishing tank is H, H is greater than h, and h is the height of the liquid level in the oil replenishing tank corresponding to the volume difference between the rodless chamber and the rod chamber of the hydraulic cylinder; The inlet and exhaust pipeline is equipped with an automatic inlet and exhaust valve which can be controlled to open and close based on the change of the liquid level in the oil replenishing tank.

2. The water inlet hydraulic system with a stable effective volume of the oil replenishment tank according to claim 1, characterized in that: The intake and exhaust pipelines include an intake and exhaust main route, an intake pipe and an outlet pipe, both of which are connected to the oil replenishing tank via an intake and exhaust main pipe, wherein an air filter and a one-way valve are installed on the intake pipe, the automatic intake and exhaust valve is installed on the intake and exhaust main pipe, and the outlet pipe is connected to a one-way valve.

3. The water inlet hydraulic system with a stable effective volume of the oil replenishment tank according to claim 1 or 2, characterized in that: An overflow pipe is mounted on the oil replenishing tank, and an overflow valve a is mounted on the overflow pipe.

4. The water inlet hydraulic system with a stable effective volume of the oil replenishment tank according to claim 1, characterized in that: The oil return pipe is connected to the control valve group, which is connected to the oil tank via the oil supply pipe and the oil discharge pipe. The oil discharge pipe is connected to the overflow valve b, and the control valve group is connected to the rod chamber of the hydraulic cylinder via the pressure oil pipe.

5. The water inlet hydraulic system with a stable effective volume of the oil replenishment tank according to claim 1, characterized in that: The H is greater than the sum of h and the height in the oil replenishing tank corresponding to the expansion volume of the oil.

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