机械毕业设计英文外文翻译199混凝土泵车液压系统的认识

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Understanding of concrete pump hydraulic system

Pumping Hydraulic system

Boom hydraulic system

Outrigger hydraulic system

Hydraulic system diagram

Daily check and maintenance of the hydraulic system

The functions of the truck mounted concrete pump, hydraulic system can be divided into pumping hydraulic system, boom hydraulic system, outrigger hydraulic system.

Pumping Hydraulic system Is divided into three parts: main pumping system, distribution and lubricating system, mixing and cooling and cleaning system.

Main pumping system

There are two hydraulic loops: open and close loop.

The Open loop: uses an A11VLO190 variable displacement of axial piston pump. It is fitted with a constant power control device, pressure cut-off valve and electrical

stroke limiter with proportional solenoid. The constant power control device has been set in the factory. The displacement can be

adjusted from 0 to Maximum by turning the oil pump displacement potentiometer on the control panel from low to high.

Fig. 1 A11VLO 190

A，B Service port (without charging pump) 420 bar

S Suction port (with charging pump) 35 bar T1, T2 Air bleed, tank

R Air bleed, oil drain

M1Measuring point, regulating chamber

M Measuring point, service port

G Port for positioning pressure (controller) for version with stroke limiter

(H.., U2), HD and EP with screwed fitting GE10 – PLM (otherwise port G closed)

The other is the control line, which can change the flow direction and the displacement of main pump through constant power valve,

proportional solenoid pressure reducing valve, directional control valve and servo valve of main pump.

The Closed loop: There is an auxiliary pump with relief valve that the setting pressure is 3.5Mpa in A4VG180. The auxiliary pump has two

output ways. One is the charge oil line, which connects with suction line of main pump through the check valve in two pressure relief valves and add oil to main pump. At the same time excessive hydraulic oil return to oil tank through flushing valve and cooler to realize heat exchange for closed loop.

A, B Service line ports SAE 1 1/4", high pressure series 420 bar

T1 Case drain or filling port

T2 Case drain M33×2; 18 deep

M A, M B Pressure gauge - operating pressure A, B

R Air bleed

S Boost suction port

X1, X2Control pressure ports (before the orifice)

G Pressure port for auxiliary circuit

P S Control pressure supply

Fa Filter outlet

Fa1Filter outlet (filter assembly)

Fe Filter inlet M33×2; 18 deep

F S Port from filter to suction line (cold start)

M H Port for balanced high pressure

Y1, Y2Remote control ports (only for HD control)