Sealing and cutting machine hydraulic system design considerations

Source:   Date:2014-10-28 15:46:34   Views:

(1) Selection of the working medium. Liquid-gas-driven sealer its working medium are two major categories: liquids and gases. Working gas cylinder and accumulator chamber using compressed gas, but by the energy transfer to the mold sealer shear energy mainly by liquids and gases to achieve. The pneumatic pressure in the cylinder is usually 0.6-0.8 MPa, can generally meet the requirements of shop air, or using a single-stage reciprocating compressor, the gas chamber of the accumulator can also be used with compressed air. However, the gas cylinder and accumulator amount is not big, but are a unvented loss inflated during the work, from a security point of view, the available nitrogen bottle of nitrogen as the gas source.
Available machine oil or liquid emulsion, to the different requirements of a degree of choice grades according to the ambient temperature and hydraulic components used hydraulic oil, we should consider the suitability of hydraulic components of the selection emulsion.
(2) the hydraulic system in the form of options. Press hydraulic system in different forms, there are open-loop and closed-loop points, use closed circuit, consider a closed tank and fill oil installations, oil cooling system and cooling problems. Different transmission mode, direct drive pump is divided into an accumulator and pump combination drive. Accumulator using a combination of gear pump, oil pump capacity can be reduced address and motor power, motor duty relatively stable, then the pump flow addressing system is the average amount of oil should be selected. Direct drive pump is used, the system is simple.
(3) reduction in oil heating. When the liquid through the pump, cylinder, pressure relief valve and a local variation of the pipeline, will generate heat so that temperature rise, the general in 5090 following the oil temperature should be controlled. Temperature rise will lead to thinning of the oil and pay was reduced, thereby increasing the amount of leakage and reduce the volumetric efficiency of the system, but will also affect the normal operation of the seal.
Measures to reduce heating oil are:
1) The equipment when not in working condition, the system should be in the low-pressure unloading state, in order to reduce heat generation.
2) increase the tank volume to increase the amount of heat the oil.
3) In the design of the hydraulic system, to meet the conditions required equipment operation, the valve member and strive to small and simple, pipes should be short, less elbow, pipe flow rate should not be too high. Further, by calculating the heating and cooling calculation, if the system temperature is too high, consider using a cooler.
4) Control oil source, control oil source can be supplied by a separate set of control circuit can also be taken from the main circuit. Set individually control the oil, can control the hydraulic steady work, and interfering with the main oil line, but adds a secondary device.