Calcium carbonate dry grinding hydraulic system and its control method

Abstract

The invention provides a calcium carbonate dry-grinding hydraulic system and a control method thereof. The calcium carbonate dry-grinding hydraulic system comprises an oil tank, an oil pump, a hydraulic cylinder, a millstone, a first reversing valve, a second reversing valve, a third reversing valve and a pressure sensor. The first reversing valve and the second reversing valve are connected between the oil pump and the hydraulic cylinder, so that the oil pump supplies oil to a first cavity of the hydraulic cylinder or a second cavity of the hydraulic cylinder. When the oil pump supplies oil to the second cavity and the millstone lowers, the pressure sensor measures the pressure in real time; when the measured pressure is smaller than a set upper limit, a first coil of the first reversing valve is electrified to allow the millstone to continuously lower; when the measured pressure is larger than the set upper limit, the first coil of the first reversing valve is power off and pressurizing is stopped; when the measured pressure is smaller than a set lower limit, the first coil of the first reversing valve is electrified to allow the millstone to continuously lower, and pressure supplementing is achieved; when the measured pressure is larger than the set lower limit, the millstone is in the state of pressure maintaining.

Description

technical field [0001] The invention relates to the technical field of papermaking, in particular to a calcium carbonate dry grinding hydraulic system and a control method thereof. Background technique [0002] Ground calcium carbonate is one of the indispensable fillers in the papermaking process. Heavy calcium carbonate is used in papermaking after marble is crushed, dry-milled, foamed, wet-milled, etc. In the dry-grinding system, the rise and fall of the millstone are controlled by the hydraulic system. During the milling process, the millstone must be kept A certain downward pressure ensures the complete contact between the grinding disc and the raw material, and the grinding disc rotates to grind the φ45mm stone into powdery particles of about 400 mesh. [0003] In the existing dry grinding hydraulic pressure maintaining control technology, the down-pressing solenoid valve is always energized, and the pressure is maintained by the pilot relief valve. The limitation is...

AI Technical Summary

Problems solved by technology

[0004] The present invention provides a calcium carbonate dry grinding hydraulic system and its control method to solve the problem in the prior art that due to the poor pressure adjustment performance of the grinding disc, it is easy to cause the inverter of the main engine to be overloaded, which will cause the equipment to stop and affect the production efficiency.

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