赶快为我摘几篇英语作文（优秀的）谢 急!要20篇谢

赶快为我摘几篇英语作文（优秀的）谢 急!要20篇谢
赶快为我摘几篇英语作文（优秀的）谢 急!
要20篇谢

赶快为我摘几篇英语作文（优秀的）谢 急!要20篇谢
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General Operating Principle of Hydraulic Buffers
Referring to Fig.3, under the influence of an external force the piston rod (or plunger) is pushed into the cylinder in which there isa Newtoni...

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General Operating Principle of Hydraulic Buffers
Referring to Fig.3, under the influence of an external force the piston rod (or plunger) is pushed into the cylinder in which there isa Newtonian,incompressible fluid ，for example oil.
During movement of the piston into the cylinder the fluid is forced through a precisely calibrated orifice which can be an annular orifice, slots or a throttle which transforms the pressure energy, generated in the fluid by the force of the piston, into heat energy.
The way in which the pressure energy is transformed into heat is a function of the length of the passage through the orifice, the velocity of the orifice and the geometric inlet and outlet conditions of the orifice.
The reaction force of a hydraulic buffer is therefore always a function of the plunger speed moving into the buffer cylinder.
At very low plunger speeds the dynamic throttling effect is almost zero and the reaction force of the buffer derives from the static force of the recoil spring driven mechanically or by gas depending on type of buffer.
The basic operating principle is the same for all two buffer series.
During compression of the Herkules‖ buffer, the hydraulic oil is forced through small holds in the cylinder tube to the cylinder where it is retained by a rubber membrane . This rubber membrane separates the oil from the gas reservoir which is itself enclosed by the outer reservoir tube In the fully extended position the gas(nitrogen) in the buffer is pre-compressed to about 5 bar. When the piston rod slides into the cylinder, the gas volume is compressed by the displaced oil. Since the gas volume is considerably greater than the displaced oil volume, there is only a slight increase in the gas pressure towards the end of the stroke and thus only a slight increase in the buffer reset force.

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