【正文】 element operating cycle must the maximum current capacity and the system divulges the determination(1) At the same time when more than hydraulic cylinders movement, the hydraulic pump current capacity must be bigger than the maximum current capacity which at the same time the movement several hydraulic cylinders (or motor) needs, and should consider the system divulging wears the volumetric efficiency drop after the hydraulic pump, namely ()In the formula: K is the system leakage coefficient, generally takes ~ , the great current capacity takes the small value, the small current capacity takes the great value。 When chooses the throttle valve and the velocity modulation valve, should consider its minimum stable current capacity satisfies the machine lowspeed performance the request accumulators choices accumulators use in to supplement when the hydraulic pump supplies the oil insufficiency, its dischargeable capacity is ()In the formula: A is the hydraulic cylinder active surface (m2)。 K is the hydraulic cylinder loss coefficient, when the estimate may take K = 。 T is the operating time (s). accumulators make the emergency energy, its dischargeable capacity is: ()When the accumulator uses in absorbs the pulsation to relax the hydraulic pressure impact, should take it as in the system a link if to be connected partially together synthesizes considers its dischargeable capaciAccording to the dischargeable capacity which extracts and considered other requests, then chooses the accumulator the form pipelines choices drill tubings types choiceIn the hydraulic system uses the drill tubing divides the hard tube and the hose, the choice drill tubing should have enough passes flows the section and the bearing pressure ability, simultaneously, should reduce the pipeline as far as possible, avoids the extreme turn and the section sudden change.(1) steel pipes: Center the high tension system selects the seamless steel pipe, the low pressure system selects the welded steel pipe, the steel pipe price lowly, performance good, the use is widespread(2) copper pipes: The copper tube working pressure below ~ 10MPa, the instable tune, is advantageous for the assembly。 V speed of flow which permits for the pipeline in (m/s). The mon oil suction pipe takes ~ 5 (m/s)。 The oil return pipe takes ~ 2 (m/s). drill tubings δ sizes determination ()In the formula: P is in the tube the biggest working pressure。 When p , takes n=6。 P1In order to execution working pressure.If calculates in the primary election system working pressure time the is sketchier than designation pressure to lose is much bigger than, should remove entire related part, auxiliary specification, again definite pipeline size. systems give off heat The system gives off heat originates from the system interior energy loss, like the hydraulic pump and the functional element power loss, the overflow valve overflow loses, the hydraulic valve and the pipeline pressure loss and so on.The system gives off heat the power P putation ()In the formula: PB is the hydraulic pump power input (W)。 ti For i working procedure operating time (s)。 pB1，qB1；pB2，qB2 is each hydraulic pump supplies the oil pressure and the current capacity.Hydraulic system overall effectiveness index: ()In the formula: For hydraulic pump overall effectiveness index。 For return route efficiency5 draws up the regular worker mapping and the pilation technology documentPasses through after the hydraulic system performance and the essential revision, then may draw up the regular worker mapping, it including plan hydraulic system schematic diagram, system pipeline assembly drawing and each kind of non standard part design drawing.In the official hydraulic system schematic diagram must mark various hydraulic pressure part the model specification. Regarding automaticity higher engine bed, but also should include the movement part the cycle of motion chart and the electromagnet, the pressure switch active status. determinations hydraulic system parameterMay know by the operating mode analysis in, the labor enters the stage the load strength to be biggest, therefore, the hydraulic cylinder working pressure according to this load strength putation, according to the hydraulic cylinder and the load relations, p1=40105Pa. This engine bed for the drill hole aggregate machinetool, for prevented drills through before when occurs flushes the phenomenon, the hydraulic cylinder oil discharge cavity should have the back pressure, 、p2 =6105Pa, for causes quickly to enter quickly draws back the speed to be equal, selects the differential motion cylinder, the hypothesis quickly enters the oil discharge pressure which, quickly draws back to lose for Δ p=7105Pa. choices hydraulic pressure partchooses the hydraulic pump and the electric motor(1) determines the hydraulic pump the working pressure.Front had determined the hydraulic cylinder the biggest working pressure for 40105Pa, selects the intake pipe road pressure to lose Δp=8105Pa, its adjustment pressure is generally bigger than the system biggest working pressure 5105Pa, therefore pumps working pressure PB = (40 + 8 + 5) 105 = 53105PaThis is the working pressure which the highpressured small current capacity pumps.The hydraulic cylinder quickly draws back when the working pressure quickly enters when is bigger than, takes its pressure to lose Delta p