Variable loading hydraulic system of vertical coal mill

Abstract

The utility model discloses a variable loading hydraulic system of a vertical coal mill, which is characterized in that each pump of a double pump is respectively connected with a first high-pressure double-cylinder filter and a second high-pressure double-cylinder filter, and the first high-pressure double-cylinder filter is communicated with a rodless cavity of a lifting hydraulic cylinder through a first oil supply path; an electromagnetic valve is arranged on the first oil supply way and behind the first proportional overflow valve branch; the second high-pressure double-cylinder filter is communicated with a rod cavity of the lifting hydraulic cylinder through a second oil supply path; a speed regulating valve mechanism for regulating the ascending and descending speeds of the grinding roller is arranged on the second oil supply path and behind a second proportional overflow valve branch; a coarse precision filter is arranged at an inlet of the cooler, and an energy accumulator and a safety valve on a second oil return way are integrated with the lifting hydraulic cylinder. The staying height of the oil cylinder can be controlled, the coarse precision filter is arranged at the water inlet of the cooler, impurities in water are filtered out, the energy accumulator and the safety valve are integrated with the oil cylinder, and the stability of the system is improved.

Description

Technical Field

[0001] The utility model relates to a hydraulic system for a coal vertical mill. Background Art

[0002] In the existing hydraulic system for a coal vertical mill, the lifting cylinder cannot hover at a specific oil level as required, which is not convenient for on-site maintenance; the rising and falling speeds of the grinding rollers are not adjustable, affecting the working performance and need to be further improved; there are many impurities in the water inlet of the cooler in the existing technology, affecting the service life of the cooler. In the existing technology, the accumulator and the safety valve are separately arranged from the cylinder, affecting the stability of the system. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a variable loading hydraulic system for a coal vertical mill that can control the stopping height of the cylinder, facilitate on-site maintenance, and improve the stability of the system.

[0004] The technical solution of the utility model is as follows:

[0005] A variable loading hydraulic system for a coal vertical mill includes two oil pumps communicating with an oil tank, one in use and one in reserve. The characteristics are: the oil pumps are double pumps, and each pump of the double pump is respectively connected to a first high-pressure double-tube filter and a second high-pressure double-tube filter. The first high-pressure double-tube filter communicates with the rodless cavity of the lifting hydraulic cylinder through a first oil supply line. A first proportional overflow valve branch is arranged on the first oil supply line behind the first high-pressure double-tube filter. The first proportional overflow valve on the first proportional overflow valve branch is connected to an overflow return oil line leading to the oil tank. A check valve, a filter, and a cooler are successively arranged on the overflow return oil line. An electromagnetic valve for controlling the hovering of the lifting hydraulic cylinder is arranged on the first oil supply line behind the first proportional overflow valve branch; the second high-pressure double-tube filter communicates with the rod cavity of the lifting hydraulic cylinder through a second oil supply line. A second proportional overflow valve branch is arranged on the second oil supply line behind the second high-pressure double-tube filter. The second proportional overflow valve on the second proportional overflow valve branch is connected to the overflow return oil line. A speed regulating valve mechanism for adjusting the rising and falling speeds of the grinding rollers is arranged on the second oil supply line behind the second proportional overflow valve branch; the speed regulating valve mechanism includes two speed regulating valves connected in series, and each speed regulating valve is respectively connected in parallel with a first check valve and a second check valve, and the directions of the first check valve and the second check valve are opposite; a first return oil line leading to the oil tank is connected to the first oil supply line, and a second return oil line leading to the oil tank is connected to the second oil supply line; a coarse-precision filter is arranged at the inlet of the cooler to filter impurities in the water; an accumulator and a safety valve are connected to the first return oil line; an accumulator and a safety valve are connected to the second return oil line, and the accumulator and the safety valve on the second return oil line are integrated with the lifting hydraulic cylinder.

[0006] The utility model is provided with an oil cylinder hovering device, which can remotely control the oil cylinder to stay at any height, facilitating on-site maintenance. A high-pressure double-barrel filter is arranged at the outlet of each of the double pumps to reduce oil impurities in the oil fluid and improve the system stability. The rising and falling speeds of the grinding rollers can be adjusted, effectively improving the working performance. A coarse-precision filter is arranged at the water inlet of the cooler to filter out impurities in the water and extend the service life of the cooler. The accumulator and the safety valve are integrated with the oil cylinder. Due to the short distance, the response of the accumulator and the safety valve is more rapid, reducing the vibration of the pipeline and improving the system stability. Description of the Drawings

[0007] The following further describes the utility model in conjunction with the drawings and embodiments.

[0008] Figure 1 It is a schematic structural diagram of an embodiment of the utility model. Detailed Embodiment

[0009] A variable-loading hydraulic system for a coal vertical mill includes two oil pumps 2 communicating with an oil tank 1, one in use and one in reserve. The oil pumps are double pumps, and each pump of the double pump is respectively connected to a first high-pressure double-barrel filter 3 and a second high-pressure double-barrel filter 4. The first high-pressure double-barrel filter communicates with the rodless cavity of a lifting hydraulic cylinder 5 through a first oil supply pipeline. A first proportional overflow valve branch is arranged on the first oil supply pipeline behind the first high-pressure double-barrel filter. The first proportional overflow valve 6 on the first proportional overflow valve branch is connected to an overflow return oil pipeline leading to the oil tank. A check valve 7, a filter 8, and a cooler 9 are sequentially arranged on the overflow return oil pipeline. An electromagnetic valve 10 for controlling the hovering of the lifting hydraulic cylinder is arranged on the first oil supply pipeline behind the first proportional overflow valve branch; the second high-pressure double-barrel filter communicates with the rod cavity of the lifting hydraulic cylinder through a second oil supply pipeline. A second proportional overflow valve branch is arranged on the second oil supply pipeline behind the second high-pressure double-barrel filter. The second proportional overflow valve 11 on the second proportional overflow valve branch is connected to the overflow return oil pipeline. A speed regulating valve mechanism for adjusting the rising and falling speeds of the grinding rollers is arranged on the second oil supply pipeline behind the second proportional overflow valve branch; the speed regulating valve mechanism includes two series-connected speed regulating valves 12 and 13, and each speed regulating valve is respectively connected in parallel with a first check valve 14 and a second check valve 15, and the directions of the first check valve and the second check valve are opposite; a first return oil pipeline 16 leading to the oil tank is connected to the first oil supply pipeline, and a second return oil pipeline 17 leading to the oil tank is connected to the second oil supply pipeline.

[0010] An accumulator 18 and a safety valve 19 are connected to the first return oil pipeline; an accumulator 20 and a safety valve 21 are connected to the second return oil pipeline, and the accumulator and the safety valve on the second return oil pipeline are integrated with the lifting hydraulic cylinder. A coarse-precision filter 22 is arranged at the inlet of the cooler to filter impurities in the water.

[0011] An oil cylinder hovering device is set up, and a leak-free solenoid valve is set at the outlet of the oil station. By controlling the on-off of the solenoid valve, the on-off of the oil circuit is controlled, enabling the oil cylinder to stay at any height, which is convenient for on-site maintenance. A high-pressure double-barrel filter is set at the outlet of each of the double pumps, and the oil is filtered before being supplied to the system, reducing component failures caused by impurities in the oil in the fuel tank and improving the stability of the system. A coarse-precision filter is set at the water inlet of the cooler to filter out impurities in the water and extend the service life of the cooler. The accumulator and the safety valve are integrated with the oil cylinder, making the response of the accumulator and the safety valve faster and improving the stability of the system.

Claims

1. A coal vertical mill variable loading hydraulic system, comprising two oil pumps connected to the oil tank, one for use and one for standby, characterized in that: The oil pump is a double pump, each pump of the double pump is connected to the first high-pressure double-barrel filter and the second high-pressure double-barrel filter respectively, the first high-pressure double-barrel filter is communicated with the rodless chamber of the lifting hydraulic cylinder through the first oil supply oil circuit, a first proportional overflow valve branch is arranged on the first oil supply oil circuit and behind the first high-pressure double-barrel filter, the first proportional overflow valve on the first proportional overflow valve branch is connected to the overflow return oil circuit leading to the oil tank, a one-way valve, a filter, and a cooler are arranged in sequence on the overflow return oil circuit, a solenoid valve for controlling the suspension of the lifting hydraulic cylinder is arranged on the first oil supply oil circuit and behind the first proportional overflow valve branch; the second high-pressure double-barrel filter is communicated with the rod chamber of the lifting hydraulic cylinder through the second oil supply oil circuit, and a second proportional overflow valve is arranged on the second oil supply oil circuit and behind the second high-pressure double-barrel filter Branch, the second proportional overflow valve on the second proportional overflow valve branch is connected to the overflow return oil circuit, and a speed regulating valve mechanism for adjusting the rising and falling speeds of the grinding roller is provided on the second oil supply oil circuit and behind the second proportional overflow valve branch; the speed regulating valve mechanism includes two speed regulating valves connected in series, each speed regulating valve is respectively connected in parallel with the first one-way valve and the second one-way valve, and the directions of the first one-way valve and the second one-way valve are opposite; the first oil supply oil circuit is connected to the first return oil circuit leading to the oil tank, and the second oil supply oil circuit is connected to the second return oil circuit leading to the oil tank; a coarse-precision filter is provided at the inlet of the cooler to filter impurities in the water; an accumulator and a safety valve are connected to the first return oil circuit; an accumulator and a safety valve are connected to the second return oil circuit, and the accumulator and the safety valve on the second return oil circuit are integrated with the lifting hydraulic cylinder.

Images